The hydrostaticks, or, The weight, force, and pressure of fluid bodies, made evident by physical, and sensible experiments together vvith some miscellany observations, the last whereof is a short history of coal, and of all the common, and proper accidents thereof, a subject never treated of before / by G.S.
         Sinclair, George, d. 1696.
      
       
         
           1672
        
      
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             The hydrostaticks, or, The weight, force, and pressure of fluid bodies, made evident by physical, and sensible experiments together vvith some miscellany observations, the last whereof is a short history of coal, and of all the common, and proper accidents thereof, a subject never treated of before / by G.S.
             Sinclair, George, d. 1696.
          
           [20], 319, [i.e. 317] p., [7] leaves of plates (some folded) : ill.
           
             Printed by George Swintoun, James Glen, and Thomas Brown,
             Edinburgh :
             1672.
          
           
             "The Epistle Dedicatory" signed: George Sinclair.
             Numerous errors in paging; numbers 303-304 not used in paging.
             Errata: p. [13].
             Reproduction of original in the British Library.
          
        
      
    
     
       
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         eng
      
       
         
           Hydrostatics -- Early works to 1800.
           Coal -- Early works to 1800.
        
      
    
     
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           THE
           HYDROSTATICKS
           ;
           OR
           ,
           The
           
             Weight
             ,
             Force
          
           ,
           and
           Pressure
           of
           FLUID
           BODIES
           ,
           Made
           evident
           by
           Physical
           ,
           and
           
             Sensible
             Experiments
          
           .
        
         
           TOGETHER
           VVith
           some
           
             Miscellany
             Observations
          
           ,
           the
           last
           whereof
           is
           a
           short
           History
           of
           Coal
           ,
           and
           of
           all
           the
           Common
           ,
           and
           
             Proper
             Accidents
          
           thereof
           ;
           a
           Subject
           never
           treated
           of
           before
           .
        
         
           By
           
             G.
             S.
          
           
        
         
           EDINBURGH
           ,
           Printed
           by
           
             George
             Swintoun
             ,
             Iames
             Glen
          
           ,
           and
           
             Thomas
             Brown
          
           :
           Anno
           DOM.
           1672.
           
        
      
       
         
         
           
             
               G.
               SINCLARI
               P.
               Professoris
               ,
               Hydrostatica
            
             
               EDINBURGI
               ,
               Ann.
               Dom.
               1672
            
             
               Intus
               se
               vasti
               Proteus
               tegit
               obice
               saxi
               .
            
          
        
      
       
         
         
         
         
           To
           my
           very
           Honourable
           ,
           and
           Noble
           LORD
           ,
           ROBERT
           VISCOUNT
           of
           OXFUIRD
           ,
           LORD
           MACKGILL
           of
           COUSLAND
           ,
           &c.
           
        
         
           
             My
             Noble
             Lord
             ,
          
        
         
           THe
           first
           application
           I
           make
           ,
           is
           for
           pardon
           ,
           that
           I
           have
           adventured
           to
           prefix
           your
           name
           to
           the
           Frontispice
           of
           this
           Work
           ,
           which
           in
           it self
           ,
           cannot
           be
           thought
           worthy
           of
           your
           Trust
           and
           Protection
           ;
           there
           being
           no
           proportion
           between
           the
           greatness
           of
           your
           Merit
           ,
           and
           so
           mean
           an
           Oblation
           ;
           save
           what
           flows
           from
           the
           Nobleness
           of
           the
           Subjest
           ,
           and
           the
           sincerity
           of
           his
           respects
           who
           presents
           it
           .
           It
           is
           truly
           a
           part
           of
           Philosophy
           ,
           that
           was
           
           never
           much
           Cultivated
           ,
           but
           of
           late
           ,
           except
           in
           a
           more
           abstract
           and
           subtil
           way
           ,
           which
           did
           render
           it
           less
           useful
           ;
           but
           is
           now
           more
           improven
           by
           sensible
           Manifestations
           of
           the
           Soveraign
           Mistriss
           of
           Arts
           ,
           NATURE
           her self
           .
           There
           are
           indeed
           (
           my
           Lord
           )
           many
           excellent
           Sciences
           ,
           which
           do
           merit
           the
           favour
           of
           your
           Lordships
           studies
           ,
           and
           by
           which
           your
           Noble
           Accomplishments
           might
           be
           more
           improven
           ;
           yet
           I
           am
           bold
           to
           affirm
           ,
           you
           cannot
           apply
           your
           
             Noble
             Mind
          
           to
           any
           part
           of
           Philosophy
           ,
           where
           you
           will
           find
           more
           Pleasure
           ,
           with
           less
           Pains
           ;
           more
           evidence
           of
           Reason
           ,
           with
           less
           Difficulty
           .
        
         
           The
           famous
           
             Gregorio
             Leti
          
           ,
           was
           so
           much
           an
           admirer
           of
           your
           Vertues
           ,
           that
           he
           sheltered
           under
           your
           Patrociny
           ,
           his
           
             Vita
             Di
             Sisto
             quinto
             Pontefece
             Romano
             .
          
           And
           if
           you
           were
           able
           to
           protect
           an
           envyed
           Italian
           in
           Italy
           ,
           much
           more
           may
           I
           expect
           full
           security
           from
           your
           Name
           in
           Scotland
           ,
           where
           your
           interest
           and
           relations
           are
           so
           considerable
           .
           And
           if
           he
           ,
           who
           only
           look'd
           upon
           your
           
             Vertuous
             Mind
          
           ,
           while
           it
           was
           but
           blossoming
           ,
           was
           so
           much
           perswaded
           to
           judge
           none
           
           more
           fit
           to
           Receive
           ,
           Protect
           ,
           and
           Claim
           his
           Labours
           ,
           much
           more
           I
           ,
           who
           have
           seen
           the
           accomplishment
           of
           your
           
             Vertues
             at
             home
             .
             I
          
           have
           likewise
           very
           much
           confidence
           of
           your
           Noble
           and
           Candid
           Disposition
           to
           admit
           this
           into
           your
           Favour
           ,
           and
           assurance
           of
           your
           Affection
           and
           Skill
           ,
           to
           Love
           it
           ,
           and
           Understand
           it
           ;
           both
           which
           are
           conspicuous
           ,
           the
           first
           in
           your
           encouragement
           to
           all
           Learning
           ,
           the
           other
           in
           your
           Capacity
           and
           Understanding
           to
           comprehend
           ,
           whatever
           you
           encourage
           .
        
         
           Though
           (
           my
           Lord
           )
           I
           have
           been
           much
           emboldened
           to
           offer
           this
           Dedication
           to
           your
           Lordship
           ,
           upon
           the
           account
           of
           your
           own
           
             Heroick
             Vertues
          
           ,
           yet
           I
           must
           not
           pass
           over
           in
           silence
           ,
           a
           most
           special
           Motive
           ,
           which
           to
           me
           shall
           be
           the
           last
           ,
           sparing
           to
           express
           all
           the
           great
           Causes
           oblieging
           me
           so
           to
           do
           ,
           and
           that
           is
           ,
           the
           Memory
           of
           your
           VVorthy
           and
           nearest
           Relations
           ,
           who
           are
           ,
           
             my
             Lord
             your
             Father
             ,
             Grandfather
             ,
          
           and
           Great-Grand-father
           ,
           not
           only
           memorable
           for
           their
           Vertue
           and
           Learning
           ,
           and
           peculiar
           Endowments
           ,
           whereby
           they
           were
           
           thought
           worthy
           to
           serve
           their
           King
           and
           Countrey
           ,
           in
           Council
           ,
           and
           
             Honourable
             Courts
             of
             Iustice
          
           for
           these
           many
           years
           ,
           but
           for
           the
           Dignity
           ,
           and
           Antiquity
           of
           their
           famous
           Ancestours
           .
           How
           old
           your
           Lordships
           Name
           is
           ,
           Buchanan
           testifies
           in
           the
           close
           of
           the
           
             Second
             Book
          
           of
           his
           History
           ,
           who
           writeth
           thus
           ,
           
             Certè
             Gildus
             vetus
             est
             in
             Scotia
             Nomen
             ,
             ut
             vetus
             Mackgildorum
             ,
             sive
             Mackgillorum
             gens
             indicat
             :
             è
             cujus
             posteris
             honestae
             adhuc
             in
             Scotia
             &
             Anglia
             sunt
             familiae
             .
          
           That
           is
           ,
           Surely
           Gild
           
             is
             an
             ancient
             Name
             in
          
           Scotland
           ,
           
             as
             witness
             the
             old
             Family
             of
          
           Mackgilds
           ,
           or
           Mackgills
           :
           
             of
             whose
             Posterity
             there
             are
             yet
             in
          
           Scotland
           and
           England
           
             many
             Families
             of
             good
             account
          
           .
           And
           as
           an
           instance
           of
           this
           ,
           the
           same
           Author
           tells
           us
           of
           the
           Great
           
             Thane
             of
          
           Galloway
           ,
           
             Mackgillum
             Gallovidiae
             longè
             Potentissimum
          
           ,
           in
           the
           life
           of
           Mackbeth
           ,
           who
           by
           this
           Vsurper
           was
           put
           to
           death
           for
           his
           adherence
           to
           his
           Prince
           ,
           from
           whom
           your
           Lordship
           ,
           and
           your
           worthy
           Progenitors
           are
           Lineally
           descended
           ,
           and
           of
           whom
           Buchanan
           meant
           in
           the
           foregoing
           passage
           ,
           since
           our
           Predecessors
           flourisht
           in
           his
           time
           ;
           your
           
           Great-Grand-Father
           having
           then
           been
           His
           
             Majesties
             Advocat
          
           ,
           his
           Brother
           
             Lord
             Register
          
           .
        
         
           Having
           now
           (
           my
           Noble
           Lord
           )
           laid
           before
           you
           so
           many
           considerable
           Motives
           ,
           which
           I
           humbly
           desire
           may
           prevail
           ,
           I
           cannot
           but
           make
           my
           next
           Application
           for
           Acceptance
           ,
           and
           seriously
           intreat
           this
           Work
           may
           be
           received
           into
           the
           Tuition
           of
           your
           Favour
           ,
           and
           get
           a
           full
           Protection
           from
           the
           Censorious
           ,
           and
           being
           enlightned
           with
           the
           splendor
           of
           your
           Name
           ,
           and
           receiving
           the
           impression
           of
           your
           Authority
           upon
           it
           ,
           may
           safely
           pass
           thorow
           the
           VVorld
           ,
           for
           which
           singular
           Favour
           ,
           I
           shall
           fervently
           wish
           to
           your Self
           and
           Noble
           Family
           ,
           all
           Prosperity
           ,
           and
           Happiness
           ,
           and
           shall
           think
           my self
           very
           happy
           under
           the
           Character
           of
           ,
        
         
           
             Edinburgh
             ,
             
               May
               20.
               (
               the
               day
               of
               your
               Lo.
               Birth
               and
               Majority
               )
               1672.
               
            
          
           
             My
             Noble
             Lord
             ,
          
           
             Your
             Lo.
             most
             humble
             and
             much
             oblieged
             Servant
             ,
             
               GEORGE
               SINCLAR
            
             .
          
        
      
       
         
         
         
           TO
           THE
           READER
           .
        
         
           
             Courteous
             Reader
             ,
          
        
         
           I
           Shall
           not
           detain
           thee
           entry
           with
           a
           long
           Preface
           ,
           but
           give
           a
           short
           account
           of
           what
           is
           needful
           to
           be
           known
           ,
           of
           the
           
             Cause
             ,
             Occasion
          
           ,
           and
           Matter
           of
           the
           following
           Treatise
           .
           After
           the
           publication
           of
           my
           last
           Piece
           ,
           about
           the
           Weight
           and
           Pressure
           of
           the
           Air
           ,
           I
           found
           it
           needful
           to
           treat
           of
           the
           Pressure
           of
           the
           Water
           ,
           because
           of
           the
           near
           relation
           between
           the
           two
           :
           the
           operations
           ,
           and
           effects
           of
           both
           depending
           almost
           upon
           the
           same
           Principles
           and
           Causes
           .
           And
           that
           there
           are
           many
           things
           ,
           which
           cannot
           throughly
           be
           understood
           ,
           of
           the
           Pressure
           of
           the
           Air
           ,
           without
           the
           knowledge
           of
           the
           Pressure
           of
           the
           Water
           :
           therefore
           to
           make
           the
           first
           the
           more
           evident
           ,
           I
           have
           spoken
           of
           the
           second
           :
           the
           effects
           and
           operations
           of
           
             Hydrostatical
             Experiments
          
           ,
           being
           more
           conspicuous
           and
           sensible
           ,
           then
           the
           effects
           and
           operations
           of
           the
           other
           .
        
         
           The
           Occasion
           was
           some
           spare
           time
           I
           had
           now
           and
           then
           ,
           for
           making
           some
           Trials
           :
           part
           whereof
           are
           published
           here
           ;
           the
           rest
           being
           rather
           some
           productions
           of
           Reason
           ,
           attentively
           exercised
           on
           that
           Subject
           ;
           which
           notwithstanding
           may
           be
           called
           Experiments
           ,
           though
           never
           actually
           tried
           ,
           nor
           haply
           can
           be
           ,
           because
           of
           some
           accidental
           impediments
           :
           yet
           supposing
           they
           were
           ,
           I
           make
           it
           evident
           ,
           that
           such
           and
           such
           Phenomena
           would
           follow
           ,
           whence
           many
           necessary
           conclusions
           are
           inferred
           .
        
         
           As
           for
           the
           subject
           matter
           ,
           there
           are
           first
           ,
           moe
           then
           thirty
           Theorems
           in
           order
           to
           the
           Pressure
           of
           
             Fluid
             Bodies
          
           ,
           as
           
             Air
             ,
             Water
          
           ,
           and
           Mercury
           ,
           which
           in
           effect
           are
           nothing
           else
           ,
           but
           so
           many
           conclusions
           rationally
           deduced
           from
           various
           and
           diverse
           effects
           of
           
             Aerostatical
             ,
             Hydrostatical
          
           ,
           and
           
             Hydrargyrostatical
             Experiments
          
           ,
           which
           for
           the
           most
           part
           ,
           I
           have
           tried
           my self
           .
        
         
           There
           are
           next
           twenty
           Experiments
           briefly
           described
           ,
           by
           their
           own
           
           distinct
           Schematisms
           :
           their
           Phenomena
           ,
           according
           to
           the
           Laws
           of
           the
           Hydrostaticks
           are
           salved
           ,
           and
           several
           new
           conclusions
           inferred
           .
           A
           Proposal
           is
           likewise
           made
           of
           a
           more
           convenient
           Engine
           for
           Diving
           .
           Here
           ,
           several
           difficulties
           are
           proposed
           ,
           and
           answered
           ,
           and
           all
           the
           obvious
           Phenomena
           of
           Diving
           explicated
           .
           If
           the
           Lead
           which
           sinks
           the
           Ark
           ,
           be
           judged
           too
           weighty
           ,
           and
           big
           ,
           which
           may
           render
           it
           not
           so
           tractable
           ,
           and
           likewise
           hinder
           the
           Ark
           from
           going
           so
           near
           to
           the
           ground
           ,
           as
           is
           desirable
           ,
           and
           in
           some
           measure
           stop
           the
           sight
           ,
           (
           which
           troubles
           are
           (
           I
           suppose
           )
           incident
           to
           the
           Bell
           also
           )
           it
           may
           be
           reduced
           to
           a
           far
           less
           weight
           ,
           and
           quantity
           ,
           and
           the
           overplus
           being
           made
           ●quare
           and
           thin
           pieces
           ,
           may
           line
           the
           mouth
           of
           the
           Ark
           without
           ,
           between
           P
           Q
           and
           L
           M
           ,
           according
           to
           the
           Figure
           25
           ,
           or
           may
           be
           put
           to
           ,
           or
           taken
           away
           at
           pleasure
           .
           The
           Bell
           may
           have
           likewise
           in
           stead
           of
           this
           troublesome
           Foot-board
           ,
           a
           weighty
           Ring
           of
           Lead
           ,
           or
           two
           ,
           to
           go
           round
           about
           the
           orifice
           without
           ,
           in
           form
           of
           a
           Girth
           ,
           or
           Belt
           ,
           which
           may
           slip
           off
           and
           on
           at
           pleasure
           ,
           and
           will
           as
           conveniently
           sink
           it
           ,
           as
           if
           it
           had
           a
           weight
           appended
           :
           the
           Foot-board
           then
           may
           be
           of
           any
           form
           ,
           quantity
           ,
           or
           weight
           you
           please
           .
        
         
           There
           are
           thirdly
           some
           
             Miscellany
             Observations
          
           ,
           the
           design
           of
           which
           is
           only
           Philosophical
           .
           Some
           of
           them
           are
           Experiments
           made
           with
           the
           Air-pump
           ,
           which
           I
           have
           adventured
           to
           insert
           here
           ,
           even
           though
           the
           Noble
           
             Mr.
             Boyl
          
           hath
           given
           an
           account
           of
           many
           .
           But
           because
           the
           Engine
           was
           offered
           to
           me
           by
           the
           
             Laird
             of
             Salton
          
           ,
           a
           Gentleman
           of
           a
           choise
           Spirit
           ,
           I
           could
           not
           ,
           but
           in
           obedience
           to
           his
           commands
           make
           use
           of
           it
           ,
           and
           shew
           him
           the
           Product
           .
           There
           are
           also
           two
           or
           three
           Observations
           in
           the
           close
           ,
           as
           that
           of
           the
           
             Primum
             vivens
          
           in
           Animals
           :
           of
           the
           
             Aliment
             ,
             and
             growth
             of
             plants
             :
          
           and
           of
           the
           
             motion
             of
             the
             Aliment
             in
             Trees
             .
          
           To
           all
           which
           is
           added
           a
           short
           
             History
             of
             Coal
          
           ,
           which
           I
           hope
           will
           be
           acceptable
           to
           some
           ;
           this
           so
           needful
           a
           subject
           ,
           never
           being
           treated
           of
           before
           by
           any
           .
           In
           it
           ,
           mention
           is
           made
           of
           things
           common
           to
           Coal
           in
           general
           ,
           as
           
             Dipps
             ,
             Rifings
          
           ,
           and
           Streeks
           .
           Next
           ,
           of
           Gaes
           ,
           or
           Dykes
           ,
           which
           prove
           so
           troublesome
           sometimes
           to
           the
           working
           of
           Coal
           .
           Thirdly
           ,
           of
           Damps
           ,
           and
           Wild-fire
           .
           Next
           ,
           a
           method
           is
           taught
           for
           trying
           of
           Grounds
           ,
           where
           never
           any
           Coal
           was
           discovered
           before
           .
           And
           lastly
           ,
           the
           manner
           how
           Levels
           ,
           or
           Conduits
           under-ground
           ,
           ought
           to
           be
           carried
           on
           ,
           for
           draining
           the
           Coal
           ,
           and
           freeing
           it
           of
           Water
           .
        
         
         
           When
           this
           Book
           was
           first
           committed
           to
           the
           Press
           ,
           I
           sent
           an
           intimation
           thereof
           to
           some
           of
           my
           friends
           ,
           for
           their
           encouragment
           to
           it
           ,
           a
           Practice
           now
           common
           ,
           and
           commendable
           ,
           which
           hath
           not
           wanted
           a
           considerable
           success
           ,
           as
           witness
           the
           respect
           of
           many
           worthy
           persons
           ,
           to
           whom
           I
           am
           oblidged
           .
           But
           there
           is
           a
           Generation
           ,
           that
           rather
           ,
           than
           they
           will
           encourage
           any
           new
           Invention
           ,
           set
           themselves
           by
           all
           means
           to
           detract
           from
           it
           ,
           and
           the
           Authors
           of
           it
           :
           so
           grieved
           are
           they
           ,
           that
           ought
           of
           this
           kind
           should
           fall
           into
           the
           hands
           of
           any
           ,
           but
           their
           own
           .
           And
           therefore
           ,
           if
           the
           Author
           shall
           give
           but
           the
           title
           of
           New
           to
           his
           Invention
           ,
           though
           never
           so
           deservedly
           ,
           
             they
             fly
             presently
             in
             his
             throat
             ,
             like
             so
             many
             Wild-Catts
             ,
          
           studying
           either
           to
           Ridicule
           his
           work
           altogether
           a
           trade
           that
           usually
           ,
           the
           person
           of
           weakest
           abilities
           ,
           and
           most
           empty
           heads
           ,
           are
           better
           at
           ,
           than
           learned
           men
           ,
           like
           those
           Schollars
           ,
           who
           being
           nimble
           in
           putting
           tricks
           ,
           and
           impostures
           upon
           their
           Condisciples
           ,
           were
           dolts
           ,
           as
           to
           their
           Lesson
           ,
           or
           else
           fall
           upon
           it
           with
           such
           snarling
           ,
           and
           carping
           ,
           as
           discover
           ,
           neither
           ingenuity
           ,
           nor
           ingeniousness
           ,
           but
           a
           sore
           sickness
           ,
           called
           Envy
           .
        
         
           In
           the
           Intimation
           ,
           I
           affirmed
           ,
           that
           the
           Doctrine
           concerning
           the
           Weight
           ,
           and
           Pressure
           of
           the
           Water
           was
           New.
           This
           one
           word
           ,
           like
           a
           spark
           of
           Fire
           falling
           accidentally
           among
           Powder
           ,
           hath
           been
           the
           occasion
           of
           so
           much
           debate
           .
           Their
           ground
           is
           ,
           because
           they
           look
           upon
           the
           Hydrostaticks
           ,
           as
           a
           
             Science
             long
             ago
             perfected
          
           ,
           seing
           Archimedes
           2000
           years
           ago
           hath
           demonstrat
           the
           Water
           to
           have
           a
           Pressure
           ,
           and
           some
           others
           since
           ,
           as
           Stevinus
           .
           They
           affirm
           likewise
           ,
           that
           all
           the
           Theorems
           ,
           and
           Experiments
           ,
           that
           are
           here
           ,
           are
           either
           deduceable
           from
           Archimedes
           ,
           and
           Stevinus
           ,
           or
           are
           the
           same
           with
           theirs
           .
           If
           these
           Gentlemen
           had
           suspended
           their
           judgment
           ,
           till
           this
           Book
           had
           been
           published
           ,
           I
           suspect
           they
           would
           not
           have
           spoken
           so
           confidently
           .
           For
           Archimedes
           his
           proposition
           ;
           they
           are
           but
           few
           ,
           and
           proven
           (
           as
           
             Mr
             Boyl
          
           saith
           )
           
             by
             no
             very
             easie
             demonstrations
             ,
             which
             have
             more
             of
             Geometrical
             subtility
             ,
             than
             usefulness
             in
             them
             .
          
           But
           these
           ,
           which
           are
           here
           proposed
           ,
           are
           not
           only
           useful
           ,
           but
           evidently
           evicted
           by
           reason
           ,
           and
           sensible
           Experiments
           ,
           even
           to
           the
           meanest
           capacities
           .
           And
           though
           some
           of
           mine
           ,
           may
           (
           perhaps
           )
           co-incide
           with
           some
           of
           his
           ,
           which
           to
           me
           is
           but
           accidental
           ,
           yet
           our
           way
           of
           procedour
           is
           
             toto
             Coelo
          
           different
           .
           His
           way
           is
           more
           Speculative
           :
           this
           is
           more
           Practical
           .
           His
           demonstrations
           
           are
           Geometrical
           :
           these
           are
           Physical
           .
           His
           propositions
           are
           but
           for
           the
           
             use
             of
             a
             few
          
           :
           these
           are
           for
           the
           
             use
             of
             all
          
           .
           His
           are
           not
           illustrated
           ,
           and
           confirmed
           by
           
             Hydrostatical
             Experiments
          
           :
           these
           are
           .
        
         
           Stevinus
           a
           late
           Writer
           keeps
           that
           same
           method
           .
           Yet
           I
           judge
           it
           easie
           to
           let
           see
           ,
           even
           in
           the
           entry
           ,
           how
           little
           cogent
           some
           of
           his
           demonstrations
           are
           ,
           without
           derogating
           from
           such
           a
           Learned
           Man.
           He
           hath
           indeed
           some
           
             Pragmatical
             Examples
          
           (
           as
           he
           calls
           them
           )
           for
           illustrating
           some
           of
           his
           
             Geometrical
             Propositions
          
           ,
           anent
           the
           Pressure
           of
           the
           Water
           ;
           but
           I
           leave
           them
           to
           be
           considered
           by
           the
           judicious
           and
           understanding
           .
           Again
           ,
           in
           this
           Method
           ,
           I
           am
           yet
           as
           much
           different
           from
           others
           ,
           who
           have
           written
           lately
           ,
           as
           from
           these
           I
           have
           been
           speaking
           of
           .
           For
           ,
           I
           not
           only
           treat
           of
           the
           Pressure
           of
           the
           Water
           ,
           but
           takes
           in
           with
           it
           ,
           the
           Pressure
           of
           the
           Air
           joyntly
           ;
           since
           to
           explicat
           sufficiently
           the
           Phenomena
           of
           the
           Hydrostaticks
           ,
           without
           it
           ,
           it
           is
           impossible
           .
           And
           yet
           fu●der
           ,
           I
           not
           only
           counterpoise
           Air
           with
           Water
           ,
           but
           Air
           with
           Mercury
           and
           Water
           with
           Mercury
           ,
           by
           which
           means
           several
           mysteries
           ,
           and
           secrets
           in
           this
           Art
           ,
           are
           discovered
           .
        
         
           There
           are
           several
           Inventions
           found
           out
           of
           late
           in
           the
           Hydrostaticks
           ,
           whose
           events
           and
           effects
           ,
           cannot
           be
           clearly
           deduced
           from
           the
           grounds
           of
           Archimedes
           ,
           and
           Stevinus
           ,
           who
           had
           not
           that
           clear
           discovery
           (
           fo●
           〈◊〉
           we
           know
           )
           of
           the
           
             Pressure
             of
             the
             Air
          
           ,
           that
           some
           now
           have
           ,
           without
           which
           ,
           these
           effects
           can
           never
           be
           sufficiently
           explained
           .
           And
           who
           doubts
           ,
           but
           others
           afterwards
           ,
           may
           make
           farder
           discoveries
           ,
           and
           profit
           the
           world
           yet
           more
           ,
           with
           their
           Inventions
           ,
           then
           any
           have
           yet
           done
           .
           Is
           then
           the
           
             Hydrostaticks
             ,
             a
             Science
             long
             ago
             perfected
             ?
          
           To
           this
           Pedantick
           Conceit
           ,
           I
           must
           again
           oppose
           the
           judgment
           of
           
             Mr.
             Boyl
          
           ,
           who
           saith
           moreover
           ,
           that
           
             the
             usefulness
             of
             this
             part
             of
             Philosophy
             hath
             been
             scarce
             known
             any
             farder
             than
             by
             name
             ,
             even
             to
             the
             generality
             of
             learned
             men
             .
          
        
         
           But
           let
           us
           suppose
           ,
           that
           the
           notion
           of
           the
           Pressure
           of
           the
           Water
           ,
           is
           of
           an
           old
           date
           ,
           even
           as
           old
           as
           the
           Flood
           (
           for
           Noah
           surely
           knew
           ,
           that
           the
           
             Pressure
             of
             the
             Water
          
           ,
           would
           sustain
           the
           Ark
           )
           and
           (
           giving
           ,
           but
           not
           granting
           )
           that
           Archimedes
           2000
           years
           ago
           hath
           written
           all
           the
           
             Principles
             of
             the
             Hydrostaticks
          
           ,
           doth
           this
           hinder
           any
           man
           now
           ,
           from
           deducing
           
             new
             Conclusions
          
           from
           these
           
             old
             Principles
          
           ?
           But
           there
           is
           here
           ,
           no
           such
           thing
           ▪
           for
           neither
           in
           this
           ,
           nor
           in
           my
           last
           Piece
           ,
           are
           my
           
           Adversaries
           able
           to
           
             trace
             me
          
           .
           'T
           is
           like
           the
           purposes
           would
           have
           been
           so
           much
           the
           better
           ,
           if
           I
           had
           followed
           other
           mens
           foot
           steps
           :
           and
           it
           is
           like
           they
           might
           have
           been
           so
           much
           the
           worse
           .
           I
           doubt
           not
           ,
           but
           I
           have
           lighted
           upon
           other
           mens
           thoughts
           in
           some
           things
           :
           and
           others
           writting
           on
           this
           same
           subject
           ,
           who
           perhaps
           are
           my
           Antipodes
           ,
           may
           fall
           upon
           mine
           .
           My
           Antagonists
           affirm
           ,
           they
           are
           able
           to
           deduce
           all
           my
           Theorems
           ,
           and
           the
           events
           of
           all
           my
           Experiments
           from
           the
           grounds
           of
           Archimedes
           and
           Stevinus
           .
           If
           
             they
             take
             not
             their
             word
             again
             ,
          
           I
           hope
           they
           will
           do
           it
           ;
           for
           now
           I
           put
           them
           to
           it
           .
           And
           though
           they
           should
           ,
           (
           which
           I
           am
           not
           affraid
           they
           shall
           do
           in
           haste
           )
           yet
           they
           must
           prove
           next
           ,
           that
           these
           Theorems
           and
           Conclusions
           ,
           so
           deduced
           ,
           are
           not
           new
           ,
           which
           all
           their
           Logick
           will
           not
           prove
           .
           But
           what
           if
           we
           do
           more
           ,
           (
           
             say
             they
          
           )
           even
           overthrow
           many
           of
           all
           your
           Aerostatical
           and
           
             Hydrostatical
             Experiments
          
           ,
           in
           this
           ,
           and
           in
           your
           last
           Peice
           ?
           I
           give
           you
           liberty
           ,
           and
           for
           your
           hire
           ,
           a
           Guiny
           for
           each
           Theorem
           ,
           or
           Experiment
           ,
           you
           are
           able
           to
           ransack
           ,
           in
           either
           of
           the
           two
           Books
           ,
           though
           they
           come
           near
           to
           an
           hundred
           .
           But
           ,
           ye
           must
           oblige
           your selves
           (
           
             my
             Masters
          
           )
           to
           do
           it
           with
           Reason
           ,
           laying
           aside
           your
           Sophistry
           and
           
             Canina
             eloquentia
          
           .
           And
           this
           I
           offer
           ,
           Reader
           ,
           that
           I
           may
           reduce
           them
           ,
           to
           a
           better
           humour
           ,
           and
           encourage
           them
           to
           leave
           off
           flyting
           ,
           and
           only
           use
           reason
           .
           Neither
           must
           they
           be
           like
           the
           Wasp
           ,
           that
           only
           lights
           upon
           the
           
             sore
             place
          
           .
           But
           if
           they
           love
           to
           kindle
           any
           more
           fire
           ,
           they
           will
           find
           me
           proof
           against
           it
           .
           If
           it
           burn
           them
           ,
           it
           shall
           not
           heat
           me
           .
           Nevertheless
           ,
           if
           they
           love
           to
           juik
           under
           deck
           ,
           
             like
             Green-horns
          
           ,
           having
           no
           courage
           in
           themselves
           ,
           or
           confidence
           in
           their
           cause
           ,
           they
           must
           excuse
           me
           ,
           if
           at
           last
           ,
           I
           write
           their
           names
           upon
           a
           Ticket
           ,
           and
           bring
           them
           above
           deck
           .
           This
           is
           all
           I
           have
           to
           say
           ,
           at
           present
           (
           Reader
           )
           and
           I
           bid
           thee
           farewell
           .
        
      
       
         
           ERRATA
           .
        
         
           Pag.
           22.
           lin
           .
           8.
           for
           weight
           read
           ben●il
           .
           Pag.
           185.
           lin
           .
           24.
           for
           E
           H
           ,
           read
           F
           H.
           Pag.
           235.
           lin
           .
           24.
           
             for
             500.
             read
          
           5000.
           
           Pag.
           307.
           lin
           .
           26.
           read
           promoting
           .
           Pag.
           313.
           lin
           .
           22.
           read
           reflection
           .
           Ibid.
           lin
           .
           25.
           read
           elaborarint
           .
           Pag.
           317.
           lin
           .
           2.
           read
           &
           magna
           .
        
         
           Note
           ,
           that
           in
           placing
           the
           Figures
           ,
           the
           12
           ,
           that
           should
           have
           the
           fourth
           place
           in
           the
           third
           Plate
           ,
           hath
           the
           first
           place
           in
           the
           fourth
           .
        
      
       
         
         
           Contents
           of
           the
           EXPERIMENTS
           .
        
         
           
             THe
             first
             ,
             second
             ,
             and
             third
             Experiment
             ,
             touching
             the
             rising
             and
             falling
             down
             of
             Water
             in
             Tubs
             of
             different
             sizes
             .
             Pag.
             37.
             41.
             44.
             
          
           
             The
             fourth
             is
             a
             
               Hydrostatical
               Experiment
            
             ,
             shewing
             the
             Reason
             why
             the
             
               Mercurial
               Cylinder
            
             rises
             ,
             and
             falls
             ,
             in
             the
             
               Torricellian
               Experiment
            
             ,
             as
             it
             is
             carried
             up
             ,
             or
             down
             thorow
             the
             
               Air.
               pag.
            
             46.
             50
          
           
             The
             fifth
             ,
             shewing
             the
             reason
             ,
             why
             the
             
               Mercurial
               Cylinder
            
             rises
             and
             falls
             in
             the
             Baroscope
             ,
             as
             the
             Pipe
             is
             reclined
             and
             erected
             .
             p.
             51
          
           
             The
             sixth
             ,
             touching
             the
             
               suspension
               of
               Liquors
            
             in
             Pipes
             ,
             either
             closs
             or
             open
             above
             ,
             not
             only
             of
             Water
             by
             Water
             ,
             but
             of
             Water
             by
             Air.
             
               pag.
               55
               ,
               &c.
            
             
          
           
             
               The
               seventh
               ,
               touching
               the
            
             Cause
             of
             the
             suspension
             ,
             and
             keeping
             up
             of
             Water
             in
             Weather-glasses
             .
             pag.
             59.
             
          
           
             The
             eighth
             ,
             touching
             the
             reason
             ,
             why
             a
             Stone
             weighs
             less
             in
             Water
             than
             in
             
               Air.
               pag.
               71.
               &c.
            
             
          
           
             The
             ninth
             ,
             touching
             the
             reason
             ,
             why
             under
             a
             Water
             34
             foot
             deep
             ,
             the
             hight
             of
             the
             Mercury
             in
             the
             Baroscope
             ,
             is
             58
             inches
             .
             
               pag.
               77.
               &c.
            
             
          
           
             The
             tenth
             ,
             touching
             the
             reason
             ,
             why
             a
             man
             gripping
             with
             his
             fingers
             the
             
               Torricellian
               Tub
            
             ,
             seems
             to
             find
             the
             weight
             of
             the
             Liquor
             within
             ,
             and
             yet
             finds
             it
             not
             .
             
               pag.
               82.
               &c.
            
             
          
           
             The
             eleventh
             ,
             touching
             the
             counterpoising
             of
             Mercury
             in
             Glass-pipes
             under-water
             ,
             by
             the
             help
             of
             a
             Ballance
             above
             ,
             adduced
             to
             prove
             that
             a
             heavy
             Body
             weighs
             as
             much
             in
             Water
             ,
             as
             in
             Air.
             pag.
             86.
             
          
           
             The
             difficulty
             answered
             ,
             
               pag.
               87.
               &c.
            
             
          
           
             The
             twelfth
             ,
             touching
             the
             reason
             ,
             why
             a
             Cylinder
             of
             Brass
             ,
             may
             be
             suspended
             by
             a
             Surface
             of
             Water
             ,
             before
             it
             touch
             the
             bottom
             ,
             that
             's
             100
             foot
             deep
             .
             
               pag.
               101.
               &c.
            
             
          
           
             The
             thirteenth
             is
             ,
             touching
             two
             
               plain
               heavy
               Bodies
            
             suspended
             under
             a
             Water
             34
             foot
             deep
             .
             pag.
             109
          
           
             
               Doctor
               Mores
            
             Argument
             against
             the
             Pressure
             of
             the
             Air
             ,
             answered
             .
             pag.
             117
          
           
             The
             fourteenth
             ,
             touching
             the
             counterpoising
             of
             Mercury
             with
             Water
             :
             of
             Mercury
             with
             Air
             and
             Water
             ;
             whence
             some
             notable
             Phenomena
             appear
             .
             
               pag.
               120.
               &c.
            
             
          
           
             The
             fifteenth
             ,
             touching
             an
             Experiment
             
             tried
             in
             a
             Water
             72
             foot
             deep
             .
             
               pag.
               127.
               &c.
            
             
          
           
             The
             sixteenth
             ,
             touching
             the
             reason
             ,
             why
             the
             different
             wideness
             of
             Tubs
             ,
             makes
             no
             alteration
             in
             the
             hight
             of
             the
             Liquors
             suspended
             in
             them
             .
             pag.
             133.
             
          
           
             The
             seventeenth
             ,
             a
             notable
             trial
             for
             proving
             the
             Pressure
             of
             the
             
               Water
               .
               pag.
               137.
               &c.
            
             
          
           
             Mr.
             Boyls
             Experiment
             in
             sufficient
             .
             pag.
             146.
             
          
           
             The
             eighteenth
             ,
             touching
             the
             
               Diving-Ark
               .
               pag.
               153.
               &c.
            
             
          
           
             The
             nineteenth
             ,
             touching
             a
             Siphon
             made
             to
             work
             under
             Water
             with
             Mercury
             ,
             by
             the
             Pressure
             thereof
             ,
             as
             a
             Siphon
             operats
             with
             Water
             ,
             by
             the
             Pressure
             of
             the
             
               Air.
               p.
            
             180.
             
          
           
             The
             last
             is
             for
             demonstrating
             the
             precise
             and
             just
             weight
             of
             any
             Pillar
             of
             
               Air
               ,
               Water
            
             ,
             or
             
               Mercury
               .
               p.
               183.
               &c.
            
             
          
        
      
       
         
           Contents
           of
           the
           MISCELLANY
           OBSERVATIONS
           .
        
         
           
             Observation
             1
             Anent
             the
             killing
             of
             Animals
             in
             Coal-sinks
             ,
             by
             the
             power
             of
             Damps
             and
             
               Ill
               Air.
               pag.
            
             197.
             
          
           
             Observ.
             2.
             
             Touching
             the
             position
             of
             Iupiter
             ,
             with
             the
             Stars
             of
             
               Gemini
               ,
               Novemb.
               24.
               1669.
               p.
            
             201.
             
          
           
             Observ.
             3.
             
             For
             knowing
             the
             motion
             of
             the
             Sun
             ,
             or
             Moon
             ,
             in
             seconds
             of
             time
             .
             ibid.
             
          
           
             Observ.
             4.
             
             Touching
             an
             Experiment
             made
             on
             the
             top
             of
             
               Cheviot
               .
               p.
            
             207.
             
          
           
             Observ.
             5.
             
             Touching
             the
             oval-Figure
             of
             the
             Sun
             ,
             at
             his
             setting
             .
             p.
             209.
             
          
           
             Observ.
             6.
             
             Touching
             a
             considerable
             Thunder
             ,
             with
             great
             Lightnings
             ,
             in
             East-Lothian
             ,
             in
             
               Iuly
               1670.
               p.
            
             210.
             
          
           
             Observ.
             7.
             
             A
             method
             for
             finding
             out
             the
             true
             South
             and
             North
             Points
             .
             p.
             212.
             
          
           
             Observ.
             8.
             
             Touching
             the
             reason
             ,
             why
             a
             
               dead
               body
            
             of
             a
             man
             ,
             or
             beast
             ,
             riseth
             from
             the
             ground
             of
             a
             Water
             ,
             after
             it
             hath
             lien
             there
             three
             or
             four
             dayes
             .
             p.
             216.
             
          
           
             Observ.
             9.
             
             Is
             a
             second
             Experiment
             made
             in
             a
             Coal-sink
             ,
             for
             knowing
             the
             power
             of
             Damps
             and
             
               Ill-Air
               .
               p.
            
             217.
             
          
           
             Observ.
             10.
             
             An
             account
             of
             Experiments
             tried
             with
             the
             
               Air-pump
               .
               p.
            
             218.
             
          
           
             Observ.
             11.
             
             An
             Experiment
             made
             ,
             for
             knowing
             the
             reason
             ,
             why
             a
             round
             heavy
             Body
             ,
             as
             a
             Bullet
             of
             Iron
             ,
             falls
             not
             off
             a
             plain
             Body
             ,
             under
             motion
             ,
             but
             lies
             dead
             .
             p.
             224.
             
          
           
             Observ.
             12.
             
             Shewing
             the
             reason
             why
             a
             stone
             demitted
             from
             the
             
             top
             of
             a
             Ships-Mast
             under
             Sail
             ,
             falls
             directly
             upon
             the
             place
             it
             hang
             over
             .
             p.
             226.
             
          
           
             Observ.
             13.
             
             Touching
             the
             hight
             of
             the
             Mercury
             in
             the
             Baroscope
             ,
             observed
             by
             
               D.
               Beal
               .
               p.
            
             228.
             
          
           
             Observ.
             14.
             
             Touching
             the
             variation
             of
             the
             
               Magnetick
               Needle
            
             here
             .
             p.
             228.
             
          
           
             Observ.
             15.
             
             Touching
             the
             Elevation
             of
             the
             Pole
             here
             .
             p.
             228.
             
          
           
             Observ.
             16.
             
             A
             second
             method
             for
             finding
             the
             
               Meridian
               .
               p.
            
             229.
             
          
           
             Observ.
             17.
             
             Touching
             a
             considerable
             showre
             of
             Hail
             ,
             with
             Thunder
             ,
             and
             
               Rain
               .
               ibid.
            
             
          
           
             Observ.
             18.
             
             Touching
             a
             curious
             Experiment
             made
             lately
             in
             Germany
             ,
             for
             shewing
             the
             wonderful
             force
             of
             the
             Air.
             p.
             230.
             
          
           
             Observ.
             19.
             
             Touching
             some
             proposals
             of
             new
             Engines
             for
             
               War.
               p.
            
             233.
             
          
           
             Observ.
             20.
             
             Touching
             a
             sad
             trial
             one
             Mr.
             Campbel
             suffered
             in
             his
             Family
             for
             many
             dayes
             from
             the
             
               Devil
               .
               p.
            
             238.
             
          
           
             Observ.
             21.
             
             Touching
             a
             large
             Horn
             cut
             off
             a
             Womans
             head
             lately
             .
             p.
             248.
             
          
           
             Observ.
             22.
             
             Touching
             the
             
               Primum
               vivens
            
             in
             
               Animals
               .
               ibid.
            
             
          
           
             
               Observ.
               23.
               
               Touching
               the
            
             Aliment
             and
             growth
             of
             Plants
             p.
             252.
             
          
           
             
               And
               touching
               the
            
             motion
             of
             the
             aliment
             in
             Trees
             .
             p.
             254.
             
          
           
             
               Observ.
               24.
               
               Touching
               a
            
             History
             of
             Coal
             .
             p.
             258.
             
          
        
      
       
         
           In
           Auctorem
           &
           Opus
           ENCOMIASTICON
           .
        
         
           AETheris
           expansi
           ,
           vitrei
           Maris
           Antitalanton
           ,
        
         
           
             Peroledos
             ,
             Elasin
          
           ,
           Fluidarum
           ritè
           videntes
           ,
        
         
           Ingenio
           patefacta
           tuo
           ,
           Magnalia
           rerum
           ,
        
         
           Laudarûnt
           alacres
           
             Galli
             ,
             Belgaeque
          
           sagaces
           .
        
         
           Aggrederi●
           nunc
           Arte
           Novâ
           ,
           trutinare
           profundi
        
         
           Corpora
           ,
           submersas
           quondam
           producere
           Gazas
           ,
        
         
           Tollere
           demersis
           ingentia
           pondera
           Cupis
           .
        
         
           Gas
           fracidum
           in
           Cryptis
           ortum
           Fossorib●s
           atrox
           ,
        
         
           Submisso
           in
           Fundos
           Aurae
           renovante
           Flabello
           ,
        
         
           Propulsare
           doces
           ,
           Lithanthracumque
           Cavernae
        
         
           Quêis
           foveantur
           Aquis
           ,
           quo
           tendant
           ,
           unde
           oriantur
           ,
        
         
           Ordine
           quò
           circum
           Saxorum
           strata
           recumbant
           .
        
         
           Quòdbenè
           coepisti
           Naturae
           cuncta
           foventis
        
         
           Munera
           solerti
           perge
           Illustrare
           Mathesi
           .
        
         
           
             
               GEORGIUS
               HEPBURNUS
            
             ,
             M.
             D.
             à
             Monachagro
             .
          
        
      
       
         
         
           To
           the
           Reader
           .
        
         
           
             Reader
             ,
          
        
         
           THat
           thou
           mayest
           know
           ,
           by
           one
           word
           more
           ,
           how
           useful
           this
           part
           of
           Philosophy
           is
           ,
           and
           how
           far
           from
           being
           a
           
             Science
             long
             ago
             perfected
          
           ,
           take
           but
           this
           following
           proposal
           ,
           lately
           ,
           since
           my
           Book
           came
           to
           a
           close
           ,
           communicated
           to
           me
           by
           a
           Friend
           ,
           which
           ,
           by
           his
           allowance
           ,
           I
           have
           published
           ,
           reserving
           the
           Answer
           to
           himself
           ,
           the
           Author
           thereof
           .
        
         
           
             
               
                 Brother
                 ,
              
            
             
               BY
               what
               you
               have
               published
               in
               your
               
                 Ars
                 Nova
                 &
                 Magna
              
               ,
               and
               this
               Book
               ,
               I
               have
               been
               led
               to
               this
               Invention
               ,
               to
               beget
               within
               the
               Bowels
               of
               the
               Sea
               ,
               a
               Power
               ,
               or
               Force
               ,
               which
               with
               great
               safety
               ,
               and
               ease
               ,
               sh●ll
               bring
               up
               the
               greatest
               weight
               ,
               that
               can
               be
               sunk
               therein
               :
               
                 ad
                 data
                 quaecunque
                 pondera
                 demersa
                 ,
                 in
                 Ma●isv●
                 scer●bus
                 Potentiam
                 producere
                 ,
                 quae
                 mo●●
                 securo
                 ,
                 &
                 i●cili
                 ,
                 è
                 tun
                 lo
                 cujusv●s
                 altitudinis
                 ad
                 summum
                 ,
                 ipsa
                 〈◊〉
              
               I
               drew
               a
               Letter
               one
               night
               ,
               sh●wing
               the
               way
               how
               this
               might
               be
               done
               ,
               which
               I
               communicated
               to
               you
               ,
               that
               it
               might
               have
               been
               Printed
               with
               your
               Books
               but
               after
               second
               thoughts
               ,
               I
               judged
               it
               more
               meet
               to
               keep
               it
               up
               for
               a
               time
               ,
               and
               that
               it
               should
               be
               set
               forth
               by
               way
               of
               Proposal
               only
               at
               the
               first
               ,
               by
            
             
               
                 O
                 miston
                 ▪
                 
                   May
                   20.
                   1672.
                   
                
              
               
                 Your
                 Brother
                 ,
                 Mr.
                 
                   Iohn
                   Sinclar
                
                 .
              
            
          
        
         
           This
           
             New
             Invention
          
           ;
           though
           Hydrostatical
           ,
           is
           truly
           Mechanical
           there
           being
           here
           a
           ●ondus
           and
           a
           Potentia
           ,
           whose
           ope●ations
           depends
           upon
           Mechanical
           Principles
           .
           But
           in
           
           several
           respects
           it
           is
           far
           more
           admirable
           ,
           than
           the
           most
           part
           of
           the
           Mechan●cal
           Engines
           ,
           which
           are
           look'd
           upon
           as
           stupendious
           .
           Many
           things
           ,
           almost
           incredible
           ,
           are
           reported
           of
           Archimedes
           ,
           which
           he
           admirably
           brought
           about
           ,
           by
           his
           Mechanical
           Powers
           ;
           but
           I
           am
           confident
           ,
           that
           by
           this
           Invention
           ,
           as
           great
           a
           weight
           may
           be
           lifted
           ,
           if
           not
           greater
           ,
           as
           the
           Power
           of
           any
           Mechanical
           Faculty
           can
           be
           able
           to
           move
           .
           I
           know
           ,
           the
           greatest
           conceivable
           weight
           ,
           may
           be
           demonstrat
           ,
           to
           be
           moved
           by
           the
           least
           conceivable
           Power
           ,
           as
           the
           Earth
           ,
           by
           the
           
             force
             of
             a
             mans
             hand
          
           .
           But
           how
           is
           it
           possible
           to
           contrive
           Artificially
           ,
           an
           Engine
           for
           that
           purpose
           ,
           which
           will
           do
           that
           by
           Art
           ,
           which
           the
           demonstration
           makes
           evident
           by
           reason
           ?
           It
           was
           thought
           a
           great
           enterprize
           ,
           when
           
             Pope
             Sixtus
          
           the
           fifth
           ,
           transported
           an
           Obelisk
           ,
           which
           had
           been
           long
           since
           dedicated
           to
           the
           memory
           of
           
             Iulius
             Cesar
          
           ,
           from
           the
           left
           side
           of
           the
           Vatican
           ,
           to
           a
           more
           eminent
           place
           ,
           100
           foot
           distant
           ;
           but
           to
           raise
           a
           Ship
           of
           1000
           Tun
           intirely
           ,
           nay
           ,
           a
           weight
           100
           times
           greater
           ,
           is
           surely
           a
           far
           greater
           enterprize
           .
           This
           Invention
           is
           so
           much
           the
           more
           admirable
           ,
           that
           not
           only
           by
           it
           ,
           any
           supposed
           weight
           may
           be
           lifted
           ,
           but
           from
           any
           deepness
           .
           Though
           this
           (
           perhaps
           )
           cannot
           be
           done
           Mechanically
           ,
           because
           of
           some
           Physical
           ,
           or
           Moral
           impediment
           ,
           yet
           according
           to
           the
           Laws
           of
           the
           Hydrostaticks
           it
           can
           be
           demonstrat
           ,
           and
           made
           evident
           by
           reason
           .
           And
           if
           this
           be
           ,
           then
           surely
           ,
           when
           the
           Weight
           is
           determinat
           ,
           as
           the
           burdens
           of
           all
           Ships
           are
           ,
           and
           the
           deepness
           known
           to
           be
           within
           so
           many
           fathoms
           ,
           this
           Invention
           cannot
           but
           be
           successful
           .
        
         
           Though
           the
           strength
           of
           
             Mechanical
             Inventions
          
           ,
           may
           be
           multiplied
           ,
           beyond
           the
           bounds
           of
           our
           Imagination
           ,
           whereby
           the
           greatest
           Weight
           ,
           may
           be
           moved
           ,
           by
           the
           least
           Power
           ;
           yet
           the
           Wisdom
           of
           God
           ,
           hath
           thought
           it
           fit
           ,
           so
           to
           confine
           that
           knowledge
           ,
           that
           it
           cannot
           teach
           ,
           how
           both
           
           of
           them
           ,
           can
           move
           with
           the
           same
           quickness
           and
           speed
           .
           For
           ,
           if
           that
           were
           ,
           the
           very
           works
           of
           Nature
           might
           be
           overturned
           .
           Therefore
           ,
           it
           is
           observable
           ,
           that
           when
           a
           great
           Weight
           is
           moved
           by
           a
           small
           Power
           ,
           the
           motion
           of
           the
           one
           ,
           is
           as
           much
           slower
           than
           the
           motion
           of
           the
           other
           ,
           as
           the
           Weight
           of
           the
           one
           ,
           exceeds
           the
           Force
           of
           the
           other
           .
           If
           it
           were
           possible
           Mechanically
           to
           move
           the
           Earth
           with
           the
           Force
           of
           a
           mans
           hand
           ,
           the
           motion
           thereof
           would
           be
           as
           much
           slower
           ,
           than
           the
           motion
           of
           the
           hand
           ,
           as
           the
           Weight
           of
           the
           one
           ,
           exceeds
           the
           Force
           of
           the
           other
           ,
           which
           is
           a
           great
           disadvantage
           .
           And
           as
           the
           Weight
           and
           Power
           do
           thus
           differ
           ,
           as
           to
           swiftness
           ,
           and
           slowness
           in
           motion
           ,
           so
           also
           ,
           as
           to
           Space
           .
           For
           ,
           by
           how
           much
           the
           Power
           is
           in
           it self
           less
           ,
           than
           the
           Weight
           ,
           by
           so
           much
           will
           the
           bounds
           or
           Space
           ,
           the
           Weight
           moves
           thorow
           ,
           be
           less
           than
           the
           Space
           ,
           the
           Power
           goes
           thorow
           .
           If
           it
           were
           possible
           (
           keeping
           the
           same
           instance
           )
           to
           move
           the
           Earth
           with
           a
           mans
           hand
           ,
           the
           Space
           thorow
           which
           it
           passeth
           ,
           would
           differ
           as
           much
           from
           the
           Space
           the
           hand
           goes
           thorow
           ,
           as
           the
           one
           exceeds
           the
           other
           ;
           which
           is
           another
           disadvantage
           .
        
         
           It
           may
           be
           thought
           ,
           that
           if
           this
           Invention
           depend
           upon
           
             Mechanical
             Principles
          
           ,
           it
           may
           be
           obnoxious
           to
           these
           abatements
           .
           I
           answer
           ,
           though
           there
           be
           in
           it
           a
           Po●dus
           ,
           and
           a
           Potentia
           ,
           a
           Weight
           ,
           and
           a
           Power
           ,
           this
           moving
           the
           other
           ,
           yet
           it
           will
           evidently
           appear
           from
           Experience
           ,
           that
           the
           motion
           of
           the
           one
           ,
           is
           as
           swift
           as
           the
           motion
           of
           the
           other
           ,
           and
           that
           the
           one
           moves
           as
           much
           Space
           and
           bounds
           in
           the
           same
           time
           ,
           as
           the
           other
           ,
           which
           is
           a
           great
           advantage
           .
           In
           this
           ,
           it
           excells
           all
           the
           
             Mechanical
             Powers
          
           ,
           and
           Faculties
           ,
           that
           have
           ever
           yet
           been
           invented
           and
           practised
           .
           If
           any
           think
           ,
           that
           such
           a
           device
           cannot
           be
           effectuat
           ,
           without
           a
           considerable
           expence
           .
           I
           answer
           ,
           the
           expence
           is
           so
           small
           ,
           that
           I
           am
           ashamed
           to
           mention
           it
           .
           The
           method
           and
           manner
           of
           doing
           this
           ,
           is
           most
           easie
           likewise
           .
           Neither
           ought
           this
           to
           be
           a
           ground
           ,
           why
           any
           man
           
           should
           contemn
           it
           ;
           since
           the
           most
           useful
           Inventions
           ordinarily
           are
           performed
           with
           the
           greatest
           facility
           .
        
         
           As
           it
           commends
           this
           part
           of
           Philosophy
           to
           all
           ingenious
           Spirits
           ,
           as
           most
           pleasant
           ,
           and
           most
           profitable
           ,
           so
           it
           gives
           a
           check
           to
           the
           ignorant
           ,
           who
           look
           upon
           it
           as
           
             a
             Science
             long
             ago
             perfected
          
           .
        
      
       
         
           In
           praise
           of
           the
           AUTHOR
           ,
           and
           his
           WORK
           .
        
         
           
             1.
             
          
           
             WHilst
             Infant-Art
             no
             further
             did
             pretend
          
           
             Then
             to
             flat
             notions
             ,
             and
             ●
             bare
             desire
             ;
          
           
             What
             by
             small
             toyl
             we
             now
             do
             comprehend
             ,
          
           
             Our
             Pred●cessors
             only
             did
             admire
             .
          
        
         
           
             2.
             
          
           
             Now
             fruitful
             Reason
             ,
             arm'd
             with
             powerful
             Art
             ,
          
           
             Uncovers
             Nature
             to
             each
             knowing
             eye
             :
          
           
             Our
             Author
             to
             the
             World
             doth
             here
             impart
          
           
             What
             was
             before
             esteem'd
             a
             mystery
             .
          
        
         
           
             3.
             
          
           
             The
             various
             motions
             of
             that
             Element
             ,
          
           
             Whose
             liquid
             form
             gives
             birth
             to
             much
             debate
             ;
          
           
             By
             demonstration
             he
             doth
             represent
             ,
          
           
             Unfolding
             th'intrigues
             of
             that
             subtil
             state
             .
          
        
         
           
             4.
             
          
           
             The
             Wate●s
             Course
             ,
             and
             Sourse
             ,
             from
             whence
             they
             flow
             ,
          
           
             By
             him
             to
             th'sense
             so
             clearly
             are
             display'd
          
           
             Their
             current
             ●eight
             ,
             and
             Measure
             now
             we
             know
             ,
          
           
             'T
             is
             no
             more
             secret
             ,
             but
             an
             open
             Trade
             .
          
        
         
           
             W.
             C.
             
          
        
      
    
     
       
         
         
           Hydrostatical
           THEOREMS
           ,
           Containing
           some
           useful
           Principles
           in
           order
           to
           that
           excellent
           Doctrine
           ,
           anent
           the
           wonderful
           Weight
           ,
           Force
           ,
           and
           Pressure
           of
           the
           Water
           in
           its
           own
           Element
           .
        
         
           
             THEOREM
             I.
             
          
           
             In
             all
             Fluids
             ,
             besides
             the
             first
             and
             visible
             Horizontal
             surface
             ,
             there
             are
             many
             moe
             imaginary
             ,
             yet
             real
             .
             Figure
             1.
             
          
           
             FOR
             the
             better
             understanding
             the
             following
             Experiments
             ,
             it
             is
             needful
             to
             premit
             the
             subsequent
             Theorems
             ;
             the
             first
             whereof
             is
             ,
             that
             in
             all
             Fluid
             bodies
             ,
             such
             as
             Air
             ,
             Water
             ,
             and
             Mercury
             ,
             or
             any
             other
             liquid
             ,
             there
             is
             besides
             the
             first
             and
             visible
             surface
             ,
             innumerable
             moe
             imaginary
             ,
             under
             that
             first
             ,
             yet
             real
             ,
             as
             may
             be
             seen
             from
             the
             following
             Schematism
             ,
             which
             represents
             a
             Vessel
             full
             of
             Water
             ,
             where
             besides
             the
             first
             surface
             
             A
             B
             C
             D
             ,
             there
             is
             a
             second
             E
             F
             G
             H
             ,
             and
             a
             third
             I
             K
             L
             M
             ,
             and
             so
             downward
             ,
             till
             you
             come
             to
             the
             bottom
             .
             This
             holds
             true
             ,
             not
             only
             in
             Water
             ,
             but
             in
             Air
             also
             ,
             or
             in
             any
             other
             Fluid
             body
             whatsoever
             .
             I
             call
             the
             under-surfaces
             imaginary
             ,
             not
             because
             they
             are
             not
             real
             ;
             for
             true
             and
             real
             effects
             are
             performed
             by
             them
             ;
             but
             because
             they
             are
             not
             actually
             distinguished
             amongst
             themselves
             ,
             but
             only
             by
             the
             Intellect
             .
          
        
         
           
             THEOREM
             II.
             
          
           
             In
             all
             Fluids
             ,
             as
             it
             is
             needful
             to
             conceive
             Horizontal
             Plains
             ,
             so
             it
             is
             needful
             to
             conceive
             Perpendicular
             Pillars
             ,
             cutting
             these
             Plains
             at
             right
             Angles
             .
             Figure
             1.
             
          
           
             THis
             Proposition
             is
             likewise
             needful
             for
             understanding
             the
             following
             Doctrine
             ,
             anent
             the
             Pressure
             of
             the
             Water
             :
             for
             in
             it
             ,
             as
             in
             all
             Fluids
             ,
             though
             there
             be
             not
             Columes
             or
             Pillars
             actually
             divided
             ,
             reaching
             from
             the
             top
             to
             the
             bottom
             ,
             yet
             there
             are
             innumerable
             imaginary
             ,
             which
             do
             as
             really
             produce
             effects
             by
             their
             pressure
             ,
             as
             if
             they
             were
             actually
             distinguished
             .
             These
             imaginary
             Pillars
             are
             represented
             in
             the
             first
             Schematism
             ,
             one
             whereof
             is
             A
             E
             I
             N
             O
             P
             Q
             ,
             the
             other
             B
             F
             K
             R
             T
             ,
             and
             so
             forth
             .
          
        
         
           
             THEOREM
             III.
             
          
           
             There
             is
             a
             twofold
             Ballance
             ,
             one
             Natural
             ,
             another
             Artificial
             .
          
           
             BY
             the
             
               Artificial
               Ballance
            
             ,
             I
             understand
             that
             which
             the
             Mechanicks
             call
             Libra
             ,
             which
             Merchants
             commonly
             use
             .
             By
             the
             
               Natural
               Ballance
            
             (
             which
             for
             distinctions
             cause
             
             I
             so
             nominat
             )
             I
             mean
             ,
             
               v.
               g.
            
             a
             Sipho●
             ,
             or
             crooked
             Pipe
             ,
             wherein
             water
             naturally
             ascends
             or
             descends
             ,
             as
             high
             or
             low
             in
             the
             one
             Leg
             ,
             as
             in
             the
             other
             ,
             still
             keeping
             an
             evenness
             ,
             or
             likeness
             of
             weight
             .
          
        
         
           
             THEOREM
             IV.
             
          
           
             Fluid
             bodies
             counterpoise
             one
             another
             in
             the
             Ballance
             of
             Nature
             ,
             according
             to
             their
             Altitude
             only
             .
          
           
             THis
             Theorem
             will
             appear
             afterwards
             most
             evident
             ,
             while
             we
             pass
             through
             the
             several
             Experiments
             ;
             and
             it
             is
             of
             special
             use
             for
             explicating
             sundry
             difficulties
             that
             commonly
             occur
             in
             the
             Hydrostaticks
             .
             The
             meaning
             of
             it
             is
             shortly
             this
             :
             while
             two
             Cylinders
             of
             Water
             are
             in
             the
             opposite
             Scales
             of
             the
             
               Natural
               Ballance
            
             ,
             they
             do
             not
             counterpoise
             one
             another
             according
             to
             their
             thickness
             :
             for
             though
             the
             one
             Pillar
             of
             Water
             be
             ten
             times
             thicker
             ,
             then
             the
             other
             ,
             and
             consequently
             heavier
             ,
             yet
             is
             it
             not
             able
             to
             press
             up
             the
             other
             ,
             that
             's
             more
             slender
             ,
             and
             so
             lighter
             ,
             beyond
             its
             own
             hight
             :
             and
             therefore
             they
             weigh
             only
             according
             to
             their
             Altitudes
             .
          
        
         
           
             THEOREM
             V.
             
          
           
             In
             all
             Fluids
             there
             is
             a
             Pressure
             .
             Figure
             1.
             
          
           
             THis
             is
             true
             not
             only
             of
             the
             Elements
             of
             Air
             ,
             and
             Water
             ,
             while
             they
             are
             out
             of
             their
             own
             place
             (
             as
             they
             speak
             )
             but
             while
             they
             are
             in
             it
             .
             For
             Air
             and
             Water
             ,
             being
             naturally
             indued
             with
             weight
             ,
             the
             second
             foot
             cannot
             
             be
             under
             the
             first
             ,
             unless
             it
             sustain
             it
             :
             if
             this
             be
             ,
             it
             must
             necessarily
             be
             prest
             with
             its
             burden
             .
             So
             this
             Water
             being
             naturally
             a
             heavy
             body
             ,
             the
             foot
             I
             cannot
             be
             under
             E
             ,
             unless
             it
             sustain
             it
             ,
             and
             be
             prest
             with
             the
             burden
             of
             it
             ;
             the
             foot
             N
             ,
             being
             burdened
             with
             them
             both
             .
             From
             this
             Pressure
             ,
             which
             is
             in
             Air
             ,
             ariseth
             a
             certain
             sort
             of
             force
             ,
             and
             power
             ,
             which
             may
             be
             called
             Bensil
             ,
             by
             vertue
             whereof
             ,
             a
             little
             quantity
             of
             Air
             ,
             can
             expand
             and
             spread
             out
             it self
             ,
             to
             a
             very
             large
             quantity
             ,
             and
             may
             be
             extrinsick
             force
             be
             reduced
             to
             that
             small
             quantity
             again
             .
             Though
             this
             expansive
             faculty
             be
             evident
             in
             Air
             ,
             yet
             it
             is
             scarcely
             discernable
             in
             Water
             ,
             unless
             it
             be
             in
             very
             deep
             parts
             ,
             near
             the
             bottom
             ,
             where
             the
             Pressure
             is
             great
             .
             This
             Pressure
             is
             not
             of
             the
             same
             Degree
             in
             all
             the
             parts
             ,
             but
             is
             increased
             and
             augmented
             ,
             according
             to
             the
             deepness
             of
             the
             Air
             ,
             and
             Water
             :
             for
             the
             Air
             upon
             the
             tops
             of
             Mountains
             ,
             and
             high
             places
             ,
             is
             thought
             to
             be
             of
             a
             less
             Pressure
             ,
             then
             in
             Valleys
             :
             and
             Water
             is
             of
             a
             less
             Pressure
             ,
             ten
             or
             twelve
             foot
             from
             the
             top
             ,
             then
             twenty
             or
             thirty
             .
             So
             is
             the
             Water
             N
             ,
             under
             a
             far
             less
             Pressure
             ,
             then
             the
             Water
             ,
             P
             or
             Q.
             
          
        
         
           
             THEOREM
             VI.
             
          
           
             The
             pressure
             of
             Fluids
             is
             on
             every
             side
             .
             Figure
             1.
             
          
           
             THe
             meaning
             is
             ,
             that
             Air
             and
             Water
             presseth
             not
             only
             downward
             ,
             but
             upward
             ,
             not
             to
             the
             right
             hand
             only
             ,
             but
             to
             the
             left
             also
             ,
             and
             every
             way
             .
             So
             the
             foot
             of
             water
             K
             ,
             not
             only
             presseth
             down
             the
             foot
             R
             ,
             but
             presseth
             up
             the
             foot
             F
             ,
             yea
             presseth
             the
             foot
             I
             ,
             and
             the
             foot
             L
             ,
             with
             the
             same
             weight
             .
             And
             the
             first
             imaginary
             surface
             ,
             is
             as
             much
             
             prest
             up
             ,
             by
             the
             water
             I
             K
             L
             M
             ,
             as
             it
             is
             prest
             down
             by
             the
             water
             E
             F
             G
             H.
             Upon
             this
             account
             it
             is
             ,
             that
             when
             a
             Sphere
             ,
             or
             Glob
             is
             suspended
             in
             the
             midle
             of
             Water
             ,
             or
             Air
             ,
             all
             the
             points
             of
             their
             surfaces
             are
             uniformly
             prest
             .
             After
             this
             manner
             ,
             are
             our
             bodies
             prest
             with
             the
             invironing
             Air
             ,
             and
             the
             man
             that
             dives
             ,
             with
             the
             ambient
             and
             invironing
             Water
             .
          
        
         
           
             THEOREM
             VII
             .
          
           
             All
             the
             parts
             of
             a
             Fluid
             in
             the
             same
             Horizontal
             Line
             ,
             are
             equally
             prest
             .
             Figure
             1.
             
          
           
             THe
             meaning
             is
             ,
             that
             the
             foot
             I
             ,
             is
             no
             more
             prest
             ,
             then
             the
             foot
             K
             :
             neither
             is
             the
             foot
             L
             ,
             more
             burdened
             ,
             then
             the
             foot
             M.
             The
             reason
             is
             ,
             because
             each
             of
             these
             feet
             ,
             sustains
             the
             same
             weight
             :
             for
             E
             F
             G
             H
             are
             all
             of
             them
             ,
             of
             the
             same
             burden
             :
             therefore
             all
             the
             parts
             of
             a
             Fluid
             in
             the
             same
             Horizontal
             surface
             ,
             are
             prest
             most
             equally
             .
             This
             holds
             true
             in
             Air
             ,
             and
             Mercury
             ,
             or
             in
             any
             oth●●
             Liquid
             also
             .
          
        
         
           
             THEOREM
             VIII
             .
          
           
             The
             Pressure
             of
             Fluids
             seem
             to
             be
             according
             to
             Arithmetical
             Progression
             .
             Figure
             1.
             
          
           
             THe
             meaning
             is
             ,
             that
             if
             the
             first
             foot
             of
             Water
             ,
             have
             one
             Degree
             of
             Pressure
             in
             it
             ,
             the
             second
             must
             have
             only
             two
             ,
             and
             the
             third
             must
             have
             only
             three
             ,
             and
             so
             forth
             ,
             
             which
             appears
             from
             the
             Schematism
             :
             for
             the
             first
             foot
             E
             ,
             having
             one
             Degree
             of
             weight
             ,
             and
             the
             second
             foot
             I
             ,
             having
             of
             its
             self
             as
             much
             ,
             and
             sustaining
             E
             ,
             it
             must
             have
             two
             Degrees
             ,
             and
             no
             more
             .
             So
             the
             foot
             N
             ,
             sustaining
             two
             Degrees
             of
             Pressure
             from
             I
             and
             E
             ,
             must
             have
             the
             weight
             only
             of
             three
             Degrees
             ,
             O
             of
             four
             ,
             P
             of
             five
             .
             It
             's
             evident
             also
             from
             Experience
             ,
             for
             while
             by
             the
             Pressure
             of
             Water
             ,
             Mercury
             is
             suspended
             in
             a
             glass
             tub
             ,
             we
             find
             ,
             that
             as
             the
             first
             fourteen
             inches
             of
             Water
             ,
             sustains
             one
             inch
             of
             Mercury
             ,
             so
             the
             second
             fourteen
             inches
             sustains
             but
             two
             ,
             and
             the
             third
             ,
             but
             three
             .
             But
             if
             the
             Pressure
             were
             according
             to
             
               Geometrical
               progression
            
             ,
             the
             third
             foot
             of
             Water
             ought
             to
             sustain
             four
             inches
             of
             Mercury
             ,
             the
             fourth
             ,
             eight
             ;
             the
             fifth
             ,
             sixteen
             ,
             &c.
             which
             is
             contrary
             to
             Experience
             .
          
        
         
           
             THEOREM
             IX
             .
          
           
             In
             all
             Fluids
             there
             is
             a
             twofold
             weight
             ,
             one
             Sensible
             ,
             the
             other
             Insensible
             .
          
           
             THe
             first
             is
             common
             to
             all
             heavy
             bodies
             ,
             which
             we
             find
             in
             Water
             ,
             while
             we
             lift
             a
             Vessel
             full
             of
             it
             from
             the
             ground
             .
             The
             
               Insensible
               weight
            
             of
             Water
             ,
             and
             Air
             ,
             or
             of
             any
             other
             Fluid
             ,
             can
             scarcely
             be
             discerned
             by
             the
             senses
             ,
             though
             it
             be
             as
             real
             ,
             as
             the
             former
             ,
             because
             the
             Pressure
             is
             uniform
             .
             By
             vertue
             of
             the
             second
             ,
             bodies
             naturally
             lighter
             than
             Water
             ,
             are
             driven
             from
             the
             bottom
             to
             the
             top
             ,
             as
             Cork
             .
             So
             ,
             a
             man
             falling
             into
             a
             deep
             Water
             ,
             goes
             presently
             to
             the
             bottom
             ,
             and
             instantly
             comes
             up
             again
             .
             Here
             is
             a
             natural
             effect
             ,
             which
             cannot
             want
             a
             natural
             cause
             ;
             and
             this
             can
             be
             nothing
             else
             ,
             but
             the
             Pressure
             of
             the
             Water
             ,
             by
             vertue
             whereof
             he
             comes
             up
             ,
             and
             yet
             he
             finds
             nothing
             
             driving
             him
             up
             ,
             or
             pulling
             him
             up
             .
             Therefore
             ,
             there
             is
             in
             all
             Fluid
             bodies
             ,
             an
             Insensible
             weight
             ,
             as
             there
             is
             one
             Sensible
             ;
             seing
             the
             man
             that
             (
             perhaps
             )
             weighs
             seventeen
             Stone
             ,
             is
             driven
             up
             fifteen
             or
             sixteen
             fathom
             by
             it
             .
             And
             it
             must
             be
             very
             considerable
             ,
             and
             exceed
             the
             weight
             of
             the
             man
             ,
             seing
             it
             is
             able
             to
             overcome
             such
             a
             weight
             .
             So
             are
             vapours
             and
             smoke
             driven
             upward
             by
             the
             
               Insensible
               weight
            
             of
             the
             Air
             ,
             and
             by
             that
             same
             weight
             ,
             do
             the
             Clouds
             swim
             above
             us
             .
          
        
         
           
             THEOREM
             X.
             
          
           
             The
             Insensible
             weight
             of
             Fluids
             ,
             is
             only
             found
             by
             sense
             ,
             when
             the
             Pressure
             is
             not
             uniform
             .
          
           
             FOr
             understanding
             of
             this
             Proposition
             ,
             I
             must
             suppose
             somethings
             that
             are
             possible
             ,
             but
             not
             practicable
             .
             Put
             the
             case
             then
             ,
             while
             a
             man
             opens
             his
             hand
             ,
             the
             Air
             below
             were
             removed
             ,
             he
             would
             scarce
             be
             able
             to
             sustain
             the
             weight
             of
             the
             Air
             ,
             that
             rests
             upon
             the
             Palm
             above
             :
             or
             if
             the
             Air
             above
             were
             annihilated
             ,
             he
             would
             not
             be
             able
             to
             bear
             down
             the
             weight
             that
             presseth
             upward
             .
             Or
             ,
             while
             a
             Diver
             is
             in
             the
             bottom
             of
             the
             Sea
             ,
             if
             it
             were
             possible
             to
             free
             any
             one
             part
             of
             his
             body
             from
             the
             Pressure
             of
             the
             Water
             ,
             suppose
             his
             right
             arm
             ,
             I
             doubt
             not
             ,
             but
             the
             blood
             would
             spring
             out
             in
             abundance
             from
             his
             finger-ends
             :
             for
             the
             arm
             being
             free
             ,
             and
             the
             other
             parts
             extreamly
             prest
             ,
             the
             blood
             of
             necessity
             must
             be
             driven
             from
             the
             shoulder
             downward
             ,
             with
             fo●ce
             ,
             which
             cannot
             be
             without
             considerable
             pain
             .
             It
             is
             evident
             also
             ,
             from
             the
             application
             of
             the
             Cuppin-glass
             ,
             which
             being
             duely
             applied
             to
             a
             mans
             skin
             ,
             causeth
             the
             Air
             to
             press
             unequally
             ,
             the
             parts
             without
             ,
             
             being
             more
             prest
             ,
             than
             the
             parts
             within
             ,
             in
             which
             case
             the
             unequal
             Pressure
             causeth
             the
             pain
             ,
             and
             so
             is
             found
             by
             sense
             .
          
        
         
           
             THEOREM
             XI
             .
          
           
             A
             Cylinder
             of
             Water
             ,
             or
             of
             any
             other
             Fluid
             body
             ,
             loseth
             of
             its
             weight
             ,
             according
             to
             its
             reclination
             from
             a
             Perpendicular
             position
             ,
             towards
             an
             Horizontal
             or
             levell
             scituation
             .
          
           
             FOr
             understanding
             of
             this
             ,
             consider
             that
             while
             a
             Pipe
             full
             of
             Water
             stands
             perpendicular
             ,
             the
             lowest
             foot
             sustains
             the
             whole
             weight
             of
             the
             Water
             above
             it
             :
             but
             no
             sooner
             you
             begin
             to
             recline
             the
             Pipe
             from
             that
             Position
             ,
             but
             assoon
             the
             Pressure
             upon
             the
             lowest
             foot
             grows
             less
             ;
             So
             that
             if
             the
             lowest
             foot
             ,
             in
             a
             perpendicular
             position
             ,
             sustained
             the
             burden
             of
             ten
             feet
             ,
             it
             cannot
             sustain
             above
             five
             or
             six
             ,
             when
             it
             is
             half
             reclined
             .
             A
             certain
             evidence
             whereof
             is
             this
             ,
             the
             more
             a
             Cyilnder
             of
             Water
             is
             reclined
             towards
             the
             Horizon
             ,
             or
             Level
             ,
             it
             takes
             the
             shorter
             Cylinder
             of
             Water
             to
             counterpoise
             it
             ,
             as
             is
             evident
             in
             Siphons
             .
             For
             ,
             though
             the
             one
             Leg
             ,
             be
             sixteen
             inches
             long
             ,
             and
             the
             other
             but
             six
             ;
             yet
             a
             Cylinder
             of
             Water
             six
             inches
             long
             ,
             will
             counterpoise
             a
             Cylinder
             of
             sixteen
             .
             But
             this
             cannot
             be
             ,
             unless
             an
             alteration
             be
             made
             in
             the
             Pressure
             .
             For
             ,
             how
             is
             it
             possible
             ,
             that
             a
             Cylinder
             of
             Water
             can
             sometimes
             be
             in
             aequilibrio
             with
             a
             lesser
             ,
             and
             sometimes
             with
             a
             greater
             weight
             ,
             unless
             the
             Weight
             ,
             and
             Pressure
             of
             it
             ,
             be
             sometimes
             more
             ,
             and
             sometimes
             less
             ?
             When
             I
             say
             a
             Cylinder
             of
             Water
             loseth
             of
             its
             weight
             by
             reclination
             ,
             it
             is
             to
             be
             understood
             only
             of
             the
             
               Insensible
               Weight
            
             :
             for
             
             the
             
               Sensible
               Weight
            
             is
             unchangeable
             ,
             seing
             it
             is
             alwayes
             a
             Pillar
             of
             so
             many
             inches
             ,
             or
             feet
             .
             Now
             the
             true
             reason
             ,
             why
             the
             Pressure
             upon
             the
             lowest
             foot
             grows
             less
             ,
             is
             this
             ;
             the
             more
             the
             Pipe
             is
             reclined
             ,
             the
             more
             weight
             of
             the
             Cylinder
             rests
             upon
             the
             sides
             of
             the
             Pipe
             within
             ;
             by
             which
             means
             ,
             the
             lowest
             foot
             is
             eased
             of
             the
             burthen
             ,
             and
             is
             altogether
             eased
             ,
             when
             once
             the
             Pipe
             lyes
             Horizontal
             .
          
        
         
           
             THEOREM
             XII
             .
          
           
             All
             motion
             in
             Fluids
             ,
             is
             from
             the
             unequal
             Pressure
             of
             the
             Horizontal
             surface
             .
             Figure
             1.
             
          
           
             FOr
             understanding
             this
             ,
             I
             must
             distinguish
             a
             twofold
             motion
             in
             Fluids
             ;
             one
             common
             ,
             another
             proper
             ,
             by
             vertue
             of
             the
             first
             ,
             they
             incline
             ,
             as
             all
             other
             heavy
             bodies
             ,
             to
             be
             at
             the
             center
             of
             the
             Earth
             .
             It
             is
             evident
             in
             the
             motion
             of
             Rivers
             ,
             which
             descend
             from
             the
             higher
             places
             to
             the
             valleys
             ,
             even
             by
             vertue
             of
             that
             tendency
             they
             have
             to
             be
             at
             the
             center
             .
             By
             vertue
             of
             the
             second
             ,
             they
             incline
             to
             move
             every
             way
             ;
             not
             only
             downward
             ,
             but
             upward
             ,
             hither
             and
             thither
             .
             This
             sort
             of
             motion
             is
             peculiar
             ,
             and
             proper
             only
             to
             Fluids
             ;
             and
             it
             is
             that
             which
             is
             spoken
             of
             in
             this
             Theorem
             .
             I
             say
             then
             ,
             that
             all
             motion
             in
             Fluids
             ,
             is
             from
             the
             unequal
             Pressure
             of
             the
             Horizontal
             surface
             .
             For
             put
             the
             case
             A
             ,
             were
             more
             prest
             then
             B
             ,
             
               e.
               g.
            
             with
             a
             stone
             ,
             then
             surely
             as
             the
             part
             A
             descends
             ,
             the
             other
             part
             B
             will
             ascend
             ,
             and
             so
             will
             C
             and
             D
             rise
             higher
             too
             .
             Suppose
             next
             ,
             the
             part
             A
             were
             fred
             of
             the
             Pressure
             of
             the
             Air
             ,
             then
             surely
             in
             the
             same
             instant
             of
             time
             ,
             would
             the
             part
             A
             ascend
             ,
             and
             the
             parts
             B
             C
             D
             descend
             .
             As
             this
             Proposition
             is
             true
             in
             order
             
             to
             the
             first
             and
             visible
             surface
             A
             B
             C
             D
             ,
             so
             it
             is
             true
             in
             order
             to
             the
             imaginary
             surface
             I
             K
             L
             M
             ;
             for
             put
             the
             case
             the
             space
             I
             ,
             were
             filled
             with
             a
             body
             naturally
             heavier
             then
             Water
             ,
             as
             lead
             or
             stone
             ,
             then
             behoved
             that
             part
             of
             the
             surface
             to
             yeeld
             ,
             it
             being
             more
             prest
             ,
             then
             the
             part
             of
             the
             same
             surface
             K.
             Or
             if
             the
             space
             K
             were
             filled
             with
             a
             body
             naturally
             lighter
             then
             water
             ,
             as
             Cork
             ,
             then
             ought
             the
             water
             R
             to
             ascend
             ,
             it
             being
             less
             prest
             ,
             then
             the
             water
             N
             or
             S.
             
          
        
         
           
             THEOREM
             XIII
             .
          
           
             A
             body
             naturally
             heavier
             then
             Water
             ,
             descends
             ;
             and
             a
             body
             naturally
             lighter
             ,
             ascends
             .
             Figure
             1.
             
          
           
             FOr
             understanding
             of
             this
             ,
             let
             us
             suppose
             the
             quadrat
             space
             E
             ,
             to
             be
             filled
             with
             a
             piece
             of
             Lead
             or
             Iron
             .
             I
             say
             then
             it
             must
             go
             down
             to
             I
             ;
             and
             the
             reason
             is
             ,
             because
             the
             quadrat
             foot
             of
             Water
             I
             ,
             is
             more
             pressed
             then
             the
             quadrat
             foot
             of
             Water
             K.
             To
             illustrat
             this
             ,
             let
             us
             suppose
             that
             each
             quadrat
             foot
             of
             this
             Water
             weighs
             a
             pound
             ,
             and
             that
             the
             heavy
             body
             existing
             in
             E
             ,
             weighs
             two
             pound
             .
             If
             this
             be
             ,
             the
             foot
             of
             Water
             I
             ,
             must
             yeeld
             ,
             seeing
             it
             is
             more
             prest
             then
             K
             :
             upon
             the
             same
             account
             must
             the
             Water
             N
             yeeld
             ,
             and
             give
             way
             to
             the
             Stone
             ,
             seeing
             it
             is
             more
             prest
             then
             R.
             For
             according
             to
             the
             twelfth
             Theorem
             ,
             
               There
               cannot
               be
               unequal
               Pressure
               upon
               a
               surface
               ,
               unless
               motion
               follow
               .
            
          
           
             For
             understanding
             the
             second
             part
             ,
             let
             us
             suppose
             the
             space
             R
             ,
             to
             be
             filled
             with
             a
             piece
             of
             Cork
             ,
             that
             is
             specifically
             or
             naturally
             lighter
             then
             Water
             .
             I
             say
             then
             ,
             it
             must
             ascend
             to
             the
             top
             B
             ;
             and
             the
             reason
             is
             ,
             because
             the
             quadrat
             foot
             of
             Water
             K
             ,
             is
             more
             prest
             upward
             ,
             then
             the
             
             quadrat
             foot
             of
             Water
             I
             ,
             or
             L
             is
             :
             but
             this
             cannot
             be
             i●
             Fluid
             bodies
             ,
             unless
             motion
             follow
             thereupon
             .
             I
             say
             ,
             it
             is
             more
             prest
             up
             ,
             because
             R
             being
             lighter
             then
             N
             ,
             or
             S
             ,
             it
             must
             press
             with
             greater
             force
             upon
             K
             ,
             then
             S
             can
             do
             upon
             L
             ,
             or
             N
             upon
             I.
             It
             is
             still
             to
             be
             remembred
             ,
             
               That
               Fluids
               presseth
               with
               as
               much
               strength
               upward
               ,
               as
               downward
               ,
            
             according
             to
             the
             sixth
             Theorem
             ;
             and
             that
             an
             Horizontal
             surface●doth
             as
             really
             suffer
             unequal
             Pressure
             from
             below
             ,
             as
             from
             above
             .
          
        
         
           
             THEOREM
             XIV
             .
          
           
             Bodies
             naturally
             lighter
             then
             Water
             ,
             swim
             upon
             the
             surface
             and
             top
             .
             Figure
             1.
             
          
           
             THe
             reason
             of
             this
             Proposition
             must
             be
             taken
             from
             the
             nature
             of
             an
             equipondium
             ,
             or
             equal
             weight
             .
             For
             without
             doubt
             ,
             there
             is
             a
             counter-ballance
             between
             the
             Pressure
             of
             the
             Water
             ,
             and
             the
             weight
             of
             the
             body
             that
             swims
             .
             To
             make
             this
             probable
             ,
             let
             us
             suppose
             there
             were
             a
             piece
             of
             Timber
             in
             form
             of
             a
             Cube
             ,
             six
             inches
             thick
             every
             way
             ,
             without
             weight
             .
             In
             this
             case
             ,
             the
             under-surface
             of
             that
             four-squar'd
             body
             ,
             being
             applied
             to
             the
             surface
             of
             the
             Water
             A
             ,
             would
             ly
             closs
             upon
             it
             ,
             as
             one
             plain
             Table
             lyes
             upon
             the
             face
             of
             another
             ,
             without
             any
             pressure
             :
             and
             it
             being
             void
             of
             weight
             ,
             the
             part
             of
             the
             surface
             A
             ,
             would
             be
             no
             more
             burdened
             ,
             then
             the
             next
             part
             B
             adjacent
             ,
             whence
             no
             motion
             would
             follow
             .
             Here
             is
             no
             equipondium
             ,
             or
             counter-ballance
             .
          
           
             Secondly
             ,
             let
             us
             suppose
             the
             said
             body
             to
             acquire
             two
             ounces
             of
             weight
             ,
             then
             it
             follows
             ,
             that
             it
             must
             subside
             ,
             and
             sink
             two
             inches
             below
             the
             surface
             A
             B
             C
             D
             ;
             and
             that
             
             
             
             
             
             so
             far
             ,
             till
             it
             come
             by
             vertue
             of
             its
             new
             acquired
             weight
             ,
             to
             a
             counter-ballance
             with
             the
             Pressure
             of
             the
             Water
             .
             Which
             Pressure
             is
             nothing
             else
             ,
             but
             as
             much
             force
             or
             weight
             ,
             as
             is
             equivalent
             to
             the
             weight
             of
             Water
             ,
             that
             is
             thrust
             out
             of
             its
             own
             place
             ,
             by
             the
             subsiding
             and
             sinking
             of
             that
             body
             ,
             two
             inches
             .
          
           
             Thirdly
             ,
             let
             us
             suppose
             the
             same
             body
             to
             acquire
             other
             two
             ounces
             of
             weight
             ,
             then
             must
             it
             subside
             other
             two
             inches
             .
             Lastly
             ,
             let
             us
             suppose
             that
             it
             acquires
             six
             ounces
             of
             weight
             ,
             then
             it
             follows
             that
             the
             whole
             body
             sinks
             ,
             so
             far
             ,
             I
             mean
             ,
             till
             its
             upmost
             surface
             be
             in
             an
             
               Horizontal
               line
            
             with
             the
             surface
             of
             the
             Water
             A
             B
             C
             D.
             Here
             it
             swims
             also
             ,
             because
             the
             weight
             of
             it
             becomes
             just
             the
             weight
             of
             so
             much
             Water
             ,
             as
             it
             hath
             put
             out
             of
             its
             own
             place
             .
             I
             say
             ,
             it
             must
             swim
             ,
             because
             if
             the
             Water
             I
             ,
             was
             able
             to
             sustain
             the
             Water
             E
             ,
             which
             is
             put
             from
             its
             own
             place
             ,
             surely
             it
             must
             be
             able
             to
             sustain
             that
             body
             also
             ,
             that
             did
             thrust
             it
             from
             its
             own
             place
             ,
             seing
             both
             are
             of
             the
             same
             weight
             ,
             namely
             six
             ounces
             .
             In
             this
             case
             ,
             the
             body
             immerged
             ,
             and
             the
             water
             wherein
             it
             is
             drowned
             ,
             become
             of
             the
             same
             weight
             specifically
             ,
             seing
             bulk
             for
             bulk
             is
             of
             the
             same
             weight
             .
             To
             make
             this
             body
             specifically
             ,
             or
             naturally
             heavier
             then
             Water
             ,
             and
             consequently
             to
             sink
             to
             the
             bottom
             ,
             nothing
             is
             required
             ,
             but
             to
             suppose
             that
             it
             acquires
             one
             ounce
             more
             of
             weight
             ;
             which
             done
             ,
             it
             presently
             goes
             down
             ,
             I
             ,
             being
             more
             burdened
             then
             K.
             Note
             by
             the
             way
             ,
             a
             twofold
             weight
             in
             heavy
             bodies
             ,
             one
             individual
             ,
             the
             other
             specifick
             ,
             and
             that
             two
             bodies
             agreeing
             in
             individual
             weight
             ,
             may
             differ
             in
             specifick
             weight
             .
             So
             a
             pound
             of
             Lead
             ,
             and
             a
             pound
             of
             Cork
             ,
             agree
             individually
             ,
             because
             they
             are
             both
             16.
             ounces
             :
             but
             they
             differ
             specifically
             ,
             because
             the
             one
             is
             naturally
             heavier
             then
             the
             other
             .
          
        
         
           
           
             THEOREM
             XV.
             
          
           
             No
             Body
             that
             flots
             above
             Water
             ,
             even
             though
             its
             upper
             surface
             be
             level
             with
             the
             surface
             of
             the
             Water
             ,
             can
             ever
             be
             made
             to
             swim
             between
             the
             top
             and
             the
             bottom
             .
             Figure
             1.
             
          
           
             FOr
             clearing
             this
             Proposition
             ,
             let
             us
             suppose
             F
             to
             be
             a
             four-square
             piece
             of
             Timber
             ,
             of
             the
             same
             specifick
             and
             natural
             weight
             with
             Water
             ,
             and
             consequently
             its
             upper
             surface
             to
             be
             level
             with
             the
             surface
             of
             the
             Water
             A
             B
             C
             D.
             I
             say
             then
             ,
             if
             it
             be
             prest
             down
             to
             R
             ,
             it
             shall
             arise
             thence
             ,
             and
             never
             rest
             till
             it
             be
             where
             it
             was
             ,
             namely
             in
             F.
             The
             reason
             seems
             to
             be
             this
             ,
             because
             the
             four-squar'd
             body
             of
             Water
             R
             ,
             is
             really
             heavier
             ,
             then
             the
             four-squar'd
             piece
             of
             Timber
             F.
             If
             this
             be
             true
             ,
             it
             follows
             of
             necessity
             ,
             that
             it
             must
             ascend
             :
             for
             if
             the
             Timber
             existing
             in
             R
             ,
             be
             lighter
             then
             the
             Water
             R
             ,
             the
             Water
             T
             must
             be
             less
             prest
             ,
             then
             the
             Water
             O
             ,
             or
             the
             Water
             V
             ;
             whence
             (
             according
             to
             the
             twelfth
             Theorem
             )
             
               motion
               must
               follow
            
             .
             Again
             ,
             if
             the
             Timber
             R
             ,
             existing
             in
             the
             Water
             R
             ,
             be
             lighter
             then
             the
             same
             Water
             is
             ,
             then
             must
             the
             Water
             K
             ,
             be
             more
             prest
             up
             then
             the
             Water
             I
             ,
             or
             L
             ;
             whence
             yet
             ,
             according
             to
             the
             same
             Theorem
             ,
             
               motion
               must
               follow
            
             .
             If
             it
             be
             said
             ,
             that
             the
             Timber
             F
             ,
             is
             of
             the
             same
             weight
             with
             the
             Water
             R
             ,
             because
             ,
             it
             being
             equal
             in
             weight
             with
             the
             Water
             F
             ,
             which
             it
             hath
             thrust
             out
             of
             its
             own
             place
             ,
             it
             must
             also
             be
             equal
             in
             weight
             to
             the
             Water
             R
             ,
             seeing
             F
             and
             R
             being
             of
             the
             same
             dimensions
             ,
             are
             of
             the
             same
             weight
             .
             There
             is
             no
             way
             to
             answer
             this
             difficulty
             ,
             unless
             I
             say
             the
             four-squar'd
             body
             of
             water
             R
             ,
             is
             really
             and
             truly
             heavier
             then
             the
             four-squar'd
             body
             of
             Water
             F.
             The
             
             reason
             seems
             to
             be
             ,
             because
             the
             Water
             R
             ,
             is
             under
             a
             greater
             Pressure
             ,
             then
             the
             Water
             F
             ;
             and
             by
             vertue
             of
             this
             greater
             Pressure
             ,
             there
             are
             really
             
               moe
               parts
            
             of
             Water
             in
             it
             ,
             then
             in
             F
             ;
             therefore
             it
             must
             be
             heavier
             .
             Even
             as
             there
             are
             far
             moe
             parts
             of
             Air
             ,
             in
             one
             cubick
             foot
             near
             the
             Earth
             ,
             then
             in
             six
             or
             seven
             near
             the
             Atmosphere
             .
             Hence
             it
             is
             ,
             that
             a
             pint
             of
             Water
             taken
             from
             the
             bottom
             of
             the
             Sea
             ,
             fourty
             fathom
             deep
             ,
             will
             be
             heavier
             ,
             I
             mean
             in
             a
             ballance
             ,
             then
             a
             pint
             taken
             from
             the
             surface
             .
             Take
             notice
             ,
             that
             when
             the
             vessel
             is
             once
             full
             at
             the
             bottom
             ,
             the
             orifice
             must
             be
             closely
             stopped
             ,
             till
             it
             come
             to
             the
             top
             :
             otherwise
             the
             parts
             that
             are
             compressed
             at
             the
             bottom
             ,
             namely
             by
             the
             weight
             of
             the
             superiour
             parts
             ,
             relaxes
             themselves
             ,
             before
             they
             come
             to
             the
             top
             .
          
        
         
           
             THEOREM
             XVI
             .
          
           
             It
             is
             not
             impossible
             for
             a
             body
             to
             be
             suspended
             between
             the
             surface
             and
             the
             bottom
             .
             Figure
             1.
             
          
           
             FOr
             understanding
             this
             ,
             suppose
             F
             to
             be
             a
             four-square
             piece
             of
             Timber
             ,
             which
             though
             it
             will
             not
             rest
             but
             at
             the
             surface
             ,
             A
             B
             C
             D
             ,
             yet
             may
             be
             made
             to
             go
             down
             of
             its
             own
             accord
             ,
             and
             rest
             at
             T
             ,
             namely
             ,
             by
             making
             it
             so
             much
             heavier
             ,
             as
             the
             Water
             T
             is
             heavier
             then
             the
             Water
             F.
             To
             know
             this
             difference
             ,
             which
             is
             not
             very
             practicable
             ;
             the
             Cube
             of
             Water
             T
             ,
             must
             be
             brought
             from
             its
             own
             place
             ,
             under
             the
             same
             degree
             of
             Pressure
             it
             hath
             ,
             and
             put
             into
             the
             Scale
             of
             a
             Ballance
             ,
             and
             weighed
             with
             the
             Cube
             of
             Water
             F
             ,
             put
             into
             the
             other
             Scale
             .
             Now
             if
             the
             Water
             T
             ,
             be
             half
             an
             ounce
             heavier
             ,
             then
             the
             Water
             F
             ,
             then
             to
             make
             the
             Timber
             F
             hing
             in
             T
             ,
             it
             must
             be
             made
             half
             an
             ounce
             heavier
             .
             There
             seems
             to
             be
             reason
             for
             it
             also
             ;
             for
             if
             a
             
             Cube
             of
             Timber
             resting
             in
             the
             space
             T
             ,
             be
             just
             the
             weight
             of
             the
             Water
             T
             ,
             the
             imaginary
             surface
             O
             T
             V
             ,
             is
             no
             more
             prest
             ,
             then
             if
             T
             were
             Water
             ,
             and
             so
             it
             cannot
             go
             downward
             :
             neither
             can
             it
             go
             upward
             ,
             seing
             the
             under
             part
             of
             the
             Water
             R
             ,
             is
             no
             more
             prest
             up
             by
             the
             Timber
             T
             ,
             then
             if
             the
             space
             T
             were
             filled
             with
             Water
             .
             If
             it
             be
             said
             ,
             according
             to
             this
             reasoning
             ,
             a
             Stone
             may
             be
             suspended
             in
             a
             deep
             Water
             ,
             between
             the
             top
             and
             the
             bottom
             ,
             which
             is
             absurd
             .
             I
             answer
             ,
             such
             a
             thing
             may
             happen
             in
             a
             very
             deep
             Water
             :
             For
             put
             the
             case
             a
             Cube
             of
             Lead
             twelve
             inches
             every
             way
             ,
             were
             to
             go
             down
             twelve
             thousand
             fathom
             ,
             it
             is
             probable
             ,
             it
             would
             be
             suspended
             before
             it
             came
             to
             the
             ground
             .
             For
             coming
             to
             an
             imaginary
             surface
             far
             down
             ,
             where
             the
             Pressure
             is
             great
             ,
             a
             Cube
             of
             Water
             twelve
             inches
             thick
             there
             ,
             may
             be
             as
             heavy
             (
             even
             specifically
             )
             as
             the
             Cube
             of
             Lead
             is
             ,
             though
             the
             Lead
             be
             ten
             times
             heavier
             specifically
             ,
             then
             any
             foot
             of
             VVater
             at
             the
             top
             .
             If
             Water
             suffer
             compression
             of
             parts
             ,
             by
             the
             superiour
             burden
             ;
             it
             is
             more
             then
             probable
             ,
             that
             the
             second
             foot
             of
             Water
             burdened
             with
             the
             first
             ,
             hath
             moe
             parts
             in
             it
             ,
             then
             are
             in
             the
             first
             ,
             and
             the
             third
             moe
             ,
             then
             in
             the
             second
             ,
             and
             so
             forth
             ;
             and
             consequently
             ,
             that
             the
             second
             is
             heavier
             ,
             then
             the
             first
             ,
             and
             the
             third
             heavier
             ,
             then
             the
             second
             .
             Now
             ,
             if
             this
             be
             ,
             why
             may
             not
             that
             foot
             of
             Water
             ,
             that
             hath
             sixty
             thousand
             foot
             above
             it
             ,
             by
             vertue
             of
             this
             burden
             ,
             be
             so
             comprest
             ,
             that
             in
             it
             may
             be
             as
             many
             parts
             ,
             as
             may
             counter-ballance
             a
             Cube
             of
             Lead
             twelve
             inches
             every
             way
             ?
             If
             then
             ,
             that
             imaginary
             surface
             ,
             that
             is
             sixty
             thousand
             foot
             deep
             ,
             be
             able
             to
             sustain
             the
             said
             foot
             of
             VVater
             ,
             which
             perhaps
             weighs
             twenty
             pound
             ,
             why
             may
             it
             not
             likewise
             sustain
             the
             Lead
             ,
             that
             is
             both
             of
             the
             same
             dimensions
             with
             it
             ,
             and
             weight
             ?
             
             Hence
             it
             is
             ,
             that
             the
             Clouds
             do
             swim
             in
             the
             Air
             ,
             by
             vertue
             of
             a
             counter-ballance
             :
             And
             we
             see
             ,
             which
             confirms
             this
             Doctrine
             ,
             that
             the
             thinnest
             and
             lightest
             are
             alwayes
             farthest
             up
             ;
             and
             the
             thickest
             and
             blackest
             ,
             are
             alwayes
             farthest
             down
             .
          
        
         
           
             THEOREM
             XVII
             .
          
           
             The
             lower
             the
             parts
             of
             a
             Fluid
             are
             ,
             they
             are
             the
             heavier
             ,
             though
             all
             of
             them
             be
             of
             equal
             quantity
             and
             dimensions
             .
             Figure
             1.
             
          
           
             THis
             follows
             from
             the
             former
             ,
             which
             may
             appear
             a
             Paradox
             ,
             yet
             it
             seems
             to
             be
             true
             :
             for
             though
             the
             Water
             Q
             at
             the
             bottom
             ,
             be
             of
             the
             same
             dimensions
             with
             the
             Water
             E
             at
             the
             top
             ,
             yet
             it
             is
             really
             heavier
             ,
             which
             happens
             (
             as
             I
             said
             )
             from
             the
             superiour
             Pressure
             .
             It
             is
             clear
             also
             from
             this
             ,
             namely
             the
             Cube
             of
             Timber
             E
             ,
             which
             swims
             upon
             the
             surface
             ,
             being
             thrust
             down
             to
             Q
             ,
             comes
             up
             to
             the
             top
             again
             ,
             which
             could
             not
             be
             ,
             unless
             the
             Water
             Q
             ,
             were
             heavier
             then
             the
             Water
             E.
             I
             suppose
             the
             Water
             E
             ,
             and
             the
             Timber
             E
             ,
             to
             be
             exactly
             of
             the
             same
             specifick
             weight
             ,
             and
             consequently
             the
             surface
             of
             the
             Timber
             ,
             to
             ly
             Horizontal
             with
             B
             C
             D.
             Now
             the
             reason
             ,
             why
             the
             Timber
             ascends
             from
             Q
             to
             E
             ,
             is
             no
             other
             then
             this
             ,
             namely
             that
             the
             one
             Water
             is
             heavier
             then
             the
             other
             ;
             for
             the
             under
             part
             of
             the
             Water
             P
             ,
             being
             more
             prest
             up
             with
             the
             Timber
             existing
             in
             Q
             ,
             then
             with
             the
             Water
             Q
             it self
             ,
             it
             must
             yeeld
             and
             give
             way
             to
             the
             ascent
             :
             for
             if
             the
             Cube
             of
             Timber
             existing
             in
             Q
             ,
             were
             as
             heavy
             as
             the
             Water
             Q
             it self
             ,
             it
             would
             no
             more
             press
             upon
             P
             ,
             or
             endeavour
             to
             be
             up
             ,
             then
             the
             Water
             Q
             does
             .
          
        
         
           
           
             THEOREM
             XVIII
             .
          
           
             A
             heavy
             body
             weighs
             less
             in
             Water
             ,
             then
             in
             Air.
             Figure
             1.
             
          
           
             THis
             is
             easily
             proven
             from
             experience
             ;
             for
             after
             you
             have
             weighed
             a
             stone
             in
             the
             Air
             ,
             and
             finds
             it
             two
             pound
             ,
             and
             an
             half
             ,
             take
             it
             ,
             and
             suspend
             it
             by
             a
             threed
             knit
             to
             the
             scale
             of
             a
             ballance
             ;
             and
             let
             it
             down
             into
             the
             Water
             ,
             and
             you
             shall
             find
             it
             half
             a
             pound
             lighter
             .
             The
             question
             then
             is
             ,
             why
             doth
             it
             lose
             half
             a
             pound
             of
             its
             weight
             ?
             I
             answer
             ,
             the
             stone
             becomes
             half
             a
             pound
             lighter
             ,
             because
             the
             surface
             of
             Water
             on
             which
             it
             rests
             ,
             sustains
             half
             a
             pound
             of
             it
             :
             For
             put
             the
             case
             a
             stone
             were
             resting
             in
             R
             ,
             that
             weighed
             two
             pound
             and
             an
             half
             in
             the
             Air
             ,
             it
             behoved
             to
             weigh
             but
             two
             pound
             in
             this
             Water
             ;
             because
             the
             Water
             T
             sustains
             half
             a
             pound
             of
             it
             .
             For
             if
             this
             Water
             T
             be
             able
             to
             sustain
             the
             Water
             R
             ,
             that
             weighs
             half
             a
             pound
             ,
             it
             must
             be
             also
             able
             to
             sustain
             half
             a
             pound
             of
             the
             stone
             ,
             seing
             half
             a
             pound
             of
             stone
             is
             no
             heavier
             ,
             then
             half
             a
             pound
             of
             Water
             .
             Note
             ,
             that
             when
             a
             heavy
             body
             is
             weighed
             in
             Water
             ,
             it
             becomes
             so
             much
             lighter
             exactly
             ,
             as
             is
             the
             weight
             of
             the
             Water
             it
             thrusts
             out
             of
             its
             own
             place
             .
          
        
         
           
             THEOREM
             XIX
             .
          
           
             A
             heavy
             body
             weighs
             less
             nigh
             the
             bottom
             of
             the
             Water
             ,
             then
             nigh
             the
             top
             thereof
             .
             Figure
             1.
             
          
           
             FOr
             clearing
             this
             proposition
             ,
             I
             must
             suppose
             from
             the
             17.
             
             Theorem
             ,
             that
             the
             lower
             the
             parts
             of
             Water
             
             be
             ,
             they
             are
             the
             heavier
             ,
             though
             all
             of
             them
             be
             of
             equal
             dimensions
             .
             If
             then
             the
             lowest
             foot
             Q
             be
             heavier
             ,
             that
             is
             ,
             have
             moe
             parts
             in
             it
             ,
             then
             the
             foot
             N
             ,
             it
             of
             necessity
             follows
             ,
             that
             a
             stone
             suspended
             in
             Q
             ,
             must
             be
             lighter
             then
             while
             it
             is
             suspended
             in
             N
             or
             I.
             Because
             ,
             if
             a
             stone
             be
             lighter
             in
             Water
             then
             in
             Air
             ,
             as
             is
             said
             ,
             even
             by
             as
             much
             ,
             as
             is
             the
             weight
             of
             the
             bulk
             of
             Water
             ,
             that
             the
             bulk
             of
             the
             stone
             expells
             ,
             then
             surely
             it
             must
             be
             lighter
             in
             the
             one
             ,
             then
             in
             the
             other
             place
             ;
             because
             suspended
             in
             Q
             ,
             it
             expells
             moe
             parts
             of
             Water
             ,
             then
             while
             it
             is
             suspended
             in
             N
             or
             I.
             For
             example
             ,
             let
             us
             suppose
             the
             Water
             N
             ,
             to
             weigh
             eight
             ounces
             ,
             and
             the
             Water
             Q
             to
             weigh
             nine
             ,
             then
             must
             the
             stone
             suspended
             in
             Q
             ,
             weigh
             less
             by
             an
             ounce
             ,
             then
             suspended
             in
             N
             ,
             seeing
             as
             much
             is
             deduced
             from
             the
             weight
             of
             the
             stone
             ,
             as
             is
             the
             weight
             of
             the
             Water
             it
             expells
             :
             but
             so
             it
             is
             ,
             that
             it
             thrusts
             nine
             ounces
             of
             Water
             out
             of
             its
             own
             place
             in
             Q
             ,
             and
             but
             eight
             in
             N
             or
             I
             ;
             therefore
             it
             must
             be
             one
             ounce
             lighter
             in
             the
             one
             place
             ,
             then
             in
             the
             other
             .
             This
             may
             be
             tried
             ,
             with
             a
             nice
             ,
             and
             accurat
             ballance
             ,
             which
             will
             bring
             us
             to
             the
             knowledge
             of
             this
             ,
             namely
             how
             much
             the
             foot
             of
             Water
             Q
             is
             heavier
             ,
             then
             the
             Water
             N
             or
             O.
             
          
        
         
           
             THEOREM
             XX.
             
          
           
             One
             part
             of
             a
             Fluid
             ,
             cannot
             be
             under
             compression
             ,
             unless
             all
             the
             parts
             next
             adjacent
             ,
             be
             under
             the
             same
             degree
             of
             Pressure
             .
             Figure
             1.
             
          
           
             THis
             proposition
             may
             be
             proven
             by
             many
             instances
             :
             for
             when
             the
             Air
             of
             a
             Wind-gun
             ,
             is
             reduced
             to
             less
             quantity
             by
             the
             Rammer
             ,
             all
             the
             parts
             are
             most
             exactly
             of
             the
             same
             Bensil
             .
             So
             is
             it
             in
             a
             Bladder
             full
             of
             wind
             .
             It
             's
             
             true
             ,
             not
             only
             in
             order
             to
             this
             artificial
             Pressure
             ,
             but
             in
             order
             to
             the
             natural
             Pressure
             ,
             and
             Bensil
             of
             the
             Air
             likewise
             .
             For
             the
             Air
             within
             a
             parlour
             ,
             hath
             all
             its
             parts
             ,
             under
             the
             same
             degree
             of
             natural
             compression
             :
             so
             is
             it
             with
             the
             parts
             of
             the
             Air
             ,
             that
             are
             without
             ,
             and
             immediatly
             under
             the
             weight
             of
             the
             Atmosphere
             .
             It
             s
             evident
             also
             in
             the
             parts
             of
             Water
             :
             for
             the
             foot
             of
             Water
             R
             ,
             cannot
             be
             under
             Pressure
             ,
             unless
             the
             Water
             S
             ,
             and
             N
             ,
             be
             under
             the
             same
             degree
             of
             it
             .
             Though
             this
             be
             true
             of
             Fluids
             ,
             while
             all
             the
             parts
             lye
             in
             the
             same
             Horizontal
             surface
             ,
             yet
             to
             speak
             strictly
             ,
             it
             will
             not
             hold
             true
             of
             the
             parts
             scituated
             under
             divers
             surfaces
             ;
             for
             without
             question
             ,
             the
             foot
             of
             VVater
             T
             ,
             must
             be
             under
             four
             degrees
             of
             Pressure
             ,
             if
             the
             VVater
             R
             ,
             be
             under
             three
             .
             And
             if
             the
             Air
             in
             the
             lowest
             story
             of
             a
             building
             ,
             be
             under
             six
             degrees
             of
             Bensil
             ,
             the
             Air
             in
             the
             highest
             story
             must
             be
             under
             five
             .
             If
             a
             man
             would
             distinguish
             Metaphysically
             ,
             and
             subtilly
             ,
             he
             will
             find
             a
             difference
             of
             this
             kind
             ,
             not
             only
             between
             the
             first
             ,
             and
             second
             fathom
             of
             Air
             ,
             nearest
             to
             the
             Earth
             ,
             but
             between
             the
             first
             ,
             and
             second
             foot
             ;
             yea
             ,
             between
             the
             first
             and
             second
             inch
             ,
             and
             less
             ;
             much
             more
             in
             Water
             ,
             as
             to
             sense
             .
             However
             it
             be
             ,
             yet
             the
             Theorem
             holds
             true
             ;
             for
             we
             find
             no
             difference
             sensible
             ,
             between
             the
             compression
             of
             Air
             in
             this
             room
             ;
             and
             the
             compression
             of
             Air
             in
             the
             next
             room
             above
             it
             ,
             no
             not
             with
             the
             Baroscope
             ,
             or
             
               Torricellian
               Experiment
            
             ,
             that
             discerns
             such
             differences
             accurately
             .
             I
             judge
             it
             likewise
             to
             be
             true
             ,
             in
             order
             to
             the
             next
             adjacent
             parts
             of
             Fluids
             of
             different
             kinds
             ;
             for
             while
             a
             surface
             of
             Mercury
             ,
             is
             burdened
             with
             a
             Pillar
             of
             Water
             ,
             or
             a
             surface
             of
             Water
             ,
             with
             a
             Pillar
             of
             Air
             ,
             whatever
             degree
             of
             weight
             and
             Pressure
             ,
             is
             in
             the
             lowest
             parts
             of
             these
             Pillars
             ,
             the
             same
             is
             communicated
             entirely
             ,
             to
             the
             surfaces
             ,
             that
             sustains
             them
             .
             So
             then
             ,
             there
             is
             as
             much
             
             force
             and
             power
             ,
             in
             the
             surface
             of
             any
             Water
             ,
             as
             there
             is
             Weight
             and
             Pressure
             ,
             in
             the
             lowest
             foot
             of
             any
             Pillar
             of
             Air
             ,
             that
             rests
             upon
             it
             :
             otherwise
             ,
             the
             surface
             of
             Water
             would
             never
             be
             able
             to
             support
             the
             said
             Pillar
             :
             for
             a
             surface
             of
             six
             degrees
             of
             force
             ,
             can
             never
             be
             able
             to
             sustain
             a
             a
             Pillar
             of
             Air
             ,
             of
             eight
             ,
             or
             ten
             degrees
             of
             weight
             .
          
        
         
           
             THEOREM
             XXI
             .
          
           
             The
             Pressure
             of
             Fluids
             ,
             may
             be
             as
             much
             in
             the
             least
             part
             ,
             as
             in
             the
             whole
             .
             Figure
             1.
             
          
           
             THis
             Theorem
             may
             seem
             hard
             ,
             yet
             it
             can
             be
             made
             manifest
             ,
             by
             many
             instances
             :
             for
             albeit
             the
             quantity
             of
             Air
             ,
             that
             fills
             a
             Parlour
             ,
             be
             little
             in
             respect
             of
             the
             whole
             Element
             ,
             yet
             surely
             ,
             there
             is
             as
             much
             Pressure
             in
             it
             ,
             as
             in
             the
             whole
             ;
             because
             Experience
             shews
             ,
             that
             the
             
               Mercurial
               Cylinder
            
             in
             the
             Baroscope
             ,
             will
             be
             as
             well
             sustained
             in
             a
             Chamber
             ,
             as
             without
             ,
             and
             under
             the
             whole
             Atmosphere
             directly
             ;
             which
             could
             not
             be
             ,
             unless
             the
             small
             portion
             of
             Air
             ,
             that
             's
             in
             this
             Parlour
             ,
             had
             as
             much
             Pressure
             in
             it
             ,
             as
             in
             the
             whole
             Element
             .
             Besides
             this
             ,
             it
             will
             be
             found
             in
             a
             far
             less
             quantity
             :
             for
             though
             the
             Baroscope
             were
             inclosed
             ,
             and
             imprisoned
             so
             closs
             ,
             within
             a
             small
             Vessel
             ,
             that
             the
             Air
             within
             ,
             could
             have
             no
             communion
             with
             the
             Air
             without
             ,
             yet
             the
             Pressure
             of
             that
             very
             small
             quantity
             ,
             will
             sustain
             29.
             inches
             of
             Mercury
             ,
             and
             this
             will
             come
             to
             pass
             ,
             even
             though
             the
             whole
             Element
             of
             Air
             were
             annihilated
             .
             This
             Proposition
             is
             likewise
             evident
             in
             order
             to
             the
             Pressure
             of
             the
             Water
             :
             for
             put
             the
             case
             ,
             the
             Baroscope
             ,
             whose
             Mercurial
             Cylinder
             is
             29.
             inches
             ,
             by
             the
             Pressure
             of
             the
             
             Air
             ;
             were
             sent
             down
             to
             the
             bottom
             of
             a
             Sea
             34.
             foot
             deep
             ,
             within
             a
             Vessel
             ,
             as
             a
             Hogs-head
             ,
             and
             there
             exactly
             inclosed
             ,
             that
             the
             VVater
             within
             ,
             could
             have
             no
             commerce
             with
             the
             VVater
             without
             ,
             yet
             as
             well
             ,
             after
             this
             shutting
             up
             ,
             as
             before
             ,
             other
             29.
             inches
             would
             be
             sustained
             ,
             by
             the
             Pressure
             of
             this
             imprisoned
             VVater
             ,
             which
             proves
             evidently
             ,
             that
             there
             is
             as
             much
             Pressure
             in
             one
             Hogs-head
             full
             of
             VVater
             ,
             at
             the
             bottom
             of
             the
             Sea
             ,
             as
             in
             the
             whole
             Element
             of
             VVater
             ,
             above
             ,
             or
             about
             :
             for
             an
             Element
             of
             VVater
             never
             so
             spacious
             ,
             if
             it
             exceed
             not
             34.
             foot
             in
             deepness
             ,
             can
             sustain
             no
             more
             Mercury
             ,
             then
             29.
             inches
             by
             its
             Pressure
             .
             Yea
             ,
             though
             the
             Vessel
             with
             the
             Baroscope
             ,
             and
             imprisoned
             VVater
             in
             it
             ,
             were
             brought
             above
             to
             the
             free
             Air
             ,
             yet
             will
             the
             VVater
             retain
             the
             same
             Pressure
             ,
             and
             will
             
               de
               facto
            
             sustain
             29.
             inches
             of
             Mercury
             ,
             provided
             the
             Vessel
             be
             kept
             closs
             .
             It
             is
             therefore
             evident
             ,
             that
             as
             much
             Pressure
             may
             be
             in
             one
             small
             quantity
             of
             VVater
             ,
             as
             in
             the
             whole
             Element
             ,
             or
             Ocean
             .
             'T
             is
             to
             be
             observed
             ,
             that
             this
             Theorem
             is
             to
             be
             understood
             chiefly
             of
             the
             lower
             parts
             of
             Fluids
             ;
             seing
             there
             cannot
             be
             so
             much
             Pressure
             in
             the
             VVater
             P
             ,
             as
             in
             the
             VVater
             Q
             ;
             for
             in
             effect
             ,
             there
             is
             as
             much
             Pressure
             in
             the
             VVater
             Q
             ,
             as
             is
             in
             the
             whole
             VVater
             above
             it
             ,
             or
             about
             it
             .
             From
             this
             Theorem
             ,
             we
             see
             evidently
             ,
             that
             the
             Pressure
             ,
             and
             Bensil
             of
             a
             Fluid
             ,
             is
             not
             to
             be
             measured
             ,
             according
             to
             its
             bulk
             ,
             and
             quantity
             ,
             seing
             there
             is
             as
             much
             Bensil
             in
             one
             foot
             ,
             nay
             ,
             in
             one
             inch
             of
             Air
             ,
             as
             is
             in
             the
             whole
             Element
             ,
             and
             as
             strong
             a
             Pressure
             in
             one
             foot
             of
             VVater
             ,
             or
             less
             ,
             as
             there
             is
             in
             the
             whole
             Ocean
             :
             therefore
             the
             greatest
             quantity
             of
             Air
             ,
             hath
             not
             alwayes
             the
             greatest
             Bensil
             ,
             neither
             the
             greatest
             quantity
             of
             VVater
             ,
             the
             greatest
             Pressure
             .
             But
             this
             will
             appear
             more
             evident
             afterwards
             .
          
        
         
           
           
             THEOREM
             XXII
             .
          
           
             The
             Pressure
             ,
             and
             Bensil
             of
             a
             Fluid
             ,
             is
             a
             thing
             ,
             really
             distinct
             from
             the
             natural
             weight
             of
             a
             Fluid
             .
             Figure
             1.
             
          
           
             THis
             may
             be
             easily
             conceived
             ;
             for
             as
             in
             solid
             bodies
             ,
             the
             Bensil
             ,
             and
             
               natural
               weight
            
             ,
             are
             two
             distinct
             things
             ,
             so
             is
             it
             in
             Air
             ,
             and
             Water
             ,
             or
             in
             any
             other
             Fluid
             ,
             The
             weight
             of
             a
             Bow
             ,
             is
             one
             thing
             ,
             and
             the
             
               natural
               weight
            
             of
             it
             ,
             is
             another
             .
             The
             weight
             of
             the
             Spring
             of
             a
             Watch
             ,
             and
             the
             Bensil
             of
             it
             ,
             are
             two
             distinct
             things
             .
             The
             weight
             (
             perhaps
             )
             will
             not
             exceed
             two
             ounces
             :
             but
             the
             Bensil
             (
             may
             be
             )
             will
             be
             equivalent
             to
             two
             pound
             .
             Though
             these
             may
             illustrate
             ,
             yet
             they
             do
             not
             convince
             :
             therefore
             I
             shall
             adduce
             a
             reason
             ,
             and
             it
             's
             this
             .
             The
             
               natural
               weight
            
             of
             a
             Fluid
             is
             less
             ,
             or
             more
             ,
             as
             the
             quantity
             is
             less
             or
             more
             ;
             but
             it
             is
             not
             so
             with
             the
             Pressure
             ,
             because
             there
             may
             be
             as
             much
             Pressure
             in
             a
             small
             quantity
             ,
             as
             in
             a
             great
             ,
             as
             is
             evident
             from
             the
             last
             Theorem
             ,
             therefore
             they
             may
             be
             different
             .
             The
             first
             part
             of
             the
             Argument
             is
             manifest
             ,
             because
             there
             is
             more
             weight
             in
             a
             gallon
             of
             Water
             ,
             then
             in
             a
             pint
             .
             A
             second
             reason
             is
             ,
             because
             a
             Fluid
             may
             lose
             of
             its
             pressure
             ,
             without
             losing
             of
             its
             weight
             .
             This
             is
             evident
             from
             the
             Schematism
             ,
             for
             if
             you
             take
             away
             the
             four
             foot
             of
             Water
             E
             F
             G
             H
             ,
             and
             consequently
             make
             the
             four
             Pillars
             shorter
             ,
             the
             foot
             of
             Water
             Q
             becomes
             of
             less
             Pressure
             ,
             but
             not
             of
             less
             Weight
             ,
             seeing
             the
             quantity
             still
             remains
             the
             same
             :
             at
             least
             ,
             the
             loss
             of
             weight
             is
             not
             comparable
             ,
             to
             the
             loss
             of
             Pressure
             .
             I
             say
             ,
             it
             becomes
             of
             less
             Pressure
             ,
             because
             there
             is
             a
             less
             burden
             above
             it
             .
             Thirdly
             ,
             the
             Pressure
             
             and
             Bensil
             may
             be
             intended
             ,
             and
             made
             stronger
             ,
             without
             any
             alteration
             in
             the
             weight
             :
             so
             is
             the
             Bensil
             of
             Air
             ,
             within
             a
             Bladder
             ,
             made
             stronger
             by
             heat
             ,
             without
             any
             alteration
             ,
             in
             the
             weight
             of
             it
             .
             Likewise
             ,
             the
             Pressure
             of
             the
             foot
             of
             Water
             Q
             ,
             may
             be
             made
             stronger
             ,
             by
             making
             these
             four
             pillars
             higher
             ,
             without
             any
             alteration
             ,
             at
             least
             considerable
             ,
             in
             the
             weight
             ;
             for
             it
             still
             remains
             a
             foot
             of
             water
             ,
             whatever
             be
             the
             hight
             of
             the
             pillars
             above
             it
             .
             Lastly
             ,
             the
             weight
             of
             a
             Fluid
             is
             essential
             to
             it
             ,
             but
             the
             Pressure
             is
             only
             accidental
             ;
             because
             it
             is
             only
             generated
             ,
             and
             begotten
             in
             the
             inferiour
             parts
             ,
             by
             the
             weight
             of
             the
             superiour
             ,
             which
             weight
             may
             be
             taken
             away
             .
          
        
         
           
             THEOREM
             XXIII
             .
          
           
             Though
             the
             Bensil
             of
             a
             Fluid
             ,
             be
             not
             the
             same
             thing
             formally
             with
             the
             weight
             ,
             yet
             are
             they
             the
             same
             effectively
             .
          
           
             THis
             proposition
             is
             true
             in
             order
             to
             many
             other
             things
             ,
             besides
             Fluids
             :
             for
             we
             see
             that
             the
             Sun
             ,
             and
             Fire
             ,
             are
             formally
             different
             ,
             yet
             they
             may
             be
             the
             same
             effectively
             ;
             because
             the
             same
             effects
             ,
             that
             are
             done
             by
             the
             heat
             of
             the
             Sun
             ,
             may
             be
             done
             by
             the
             heat
             of
             the
             Fire
             .
             So
             the
             same
             effects
             ,
             that
             are
             produced
             by
             the
             weight
             of
             a
             Fluid
             ,
             may
             be
             done
             by
             the
             Pressure
             ,
             and
             Bensill
             of
             it
             .
             Thus
             ,
             the
             Mercurial
             Cylinder
             in
             the
             
               Torricellian
               Experiment
            
             ,
             may
             be
             either
             sustained
             by
             the
             Bensil
             of
             the
             Air
             ,
             or
             the
             weight
             of
             it
             .
             By
             the
             Bensil
             ,
             as
             when
             no
             more
             Air
             ,
             is
             admitted
             to
             rest
             upon
             the
             stagnant
             Mercury
             ,
             then
             three
             or
             four
             inches
             ,
             the
             rest
             being
             secluded
             ,
             by
             stopping
             the
             orifice
             of
             the
             Vessel
             .
             By
             the
             weight
             of
             it
             ,
             as
             when
             an
             intire
             Pillar
             of
             Air
             ,
             from
             the
             top
             of
             the
             Atmosphere
             ,
             rests
             upon
             the
             face
             of
             the
             stagnant
             
             Quicksilver
             .
             It
             is
             also
             evident
             in
             a
             Clock
             ,
             which
             may
             be
             made
             to
             move
             ,
             either
             by
             a
             weight
             of
             Lead
             ,
             or
             by
             the
             force
             ,
             and
             power
             of
             a
             Steel
             Spring
             .
          
        
         
           
             THEOREM
             XXIV
             .
          
           
             The
             surfaces
             of
             Waters
             ,
             are
             able
             to
             sustain
             any
             weight
             whatsoever
             ;
             provided
             that
             weight
             press
             equally
             ,
             and
             uniformly
             .
             Figure
             1.
             
          
           
             THis
             is
             evident
             ,
             because
             the
             imaginary
             surface
             of
             VVater
             O
             T
             V
             X
             ,
             doth
             really
             support
             the
             whole
             sixteen
             Cubes
             of
             VVater
             above
             it
             ,
             yea
             ,
             though
             they
             were
             sixteen
             thousand
             ,
             And
             the
             reason
             is
             ,
             because
             they
             press
             most
             equally
             ,
             and
             uniformly
             .
             VVhat
             I
             affirm
             of
             the
             imaginary
             surface
             ,
             the
             same
             I
             affirm
             ,
             of
             the
             first
             and
             visible
             .
             For
             let
             a
             plain
             body
             of
             lead
             ,
             never
             so
             heavy
             ,
             be
             laid
             upon
             the
             top
             of
             the
             VVater
             A
             B
             C
             D
             ,
             yet
             will
             it
             support
             it
             ,
             and
             keep
             it
             from
             sinking
             ,
             provided
             it
             press
             uniformly
             all
             the
             parts
             of
             that
             surface
             .
             It
             is
             clear
             also
             ,
             from
             the
             subsequent
             Theorem
             .
          
        
         
           
             THEOREM
             XXV
             .
          
           
             The
             surfaces
             of
             all
             Waters
             whatsoever
             ,
             support
             as
             much
             weight
             from
             the
             Air
             ,
             as
             if
             they
             had
             the
             weight
             of
             thirty
             four
             foot
             of
             Water
             above
             them
             ,
             or
             twenty
             nine
             inches
             of
             Quick-silver
             pressing
             them
             .
          
           
             THis
             Proposition
             is
             evident
             from
             this
             ,
             that
             the
             Pressure
             of
             the
             Air
             ,
             is
             able
             to
             raise
             above
             the
             surface
             of
             any
             Water
             ,
             a
             Pillar
             of
             Water
             thirty
             four
             foot
             high
             .
             For
             ,
             
             put
             the
             case
             there
             were
             a
             Pump
             fourty
             foot
             high
             ,
             erected
             among
             stagnant
             Water
             ,
             and
             a
             Sucker
             in
             it
             ,
             for
             extracting
             the
             internal
             Air
             ,
             a
             man
             will
             find
             ,
             that
             the
             Water
             will
             climb
             up
             in
             it
             four
             and
             thirty
             foot
             ;
             which
             Phenomenon
             could
             never
             happen
             ,
             unless
             the
             surface
             of
             the
             stagnant
             Water
             ,
             among
             which
             the
             end
             of
             the
             Pump
             is
             drowned
             ,
             were
             as
             much
             prest
             with
             the
             Air
             ,
             as
             if
             it
             had
             a
             burden
             of
             Water
             upon
             it
             thirty
             four
             foot
             high
             .
             The
             second
             part
             is
             also
             evident
             ,
             because
             if
             a
             man
             drown
             the
             end
             of
             a
             long
             Pipe
             ,
             in
             a
             Vessel
             with
             stagnant
             Quick-silver
             ,
             and
             remove
             the
             Air
             that
             's
             within
             the
             Pipe
             by
             a
             Sucker
             ,
             or
             more
             easily
             by
             the
             help
             of
             the
             Air-pump
             ,
             he
             will
             find
             the
             Liquor
             to
             rise
             twenty
             nine
             inches
             ,
             above
             the
             surface
             below
             ,
             which
             thing
             could
             never
             come
             to
             pass
             ,
             unless
             the
             Pressure
             of
             the
             Air
             ,
             upon
             the
             surfaces
             of
             all
             Bodies
             ,
             were
             equivalent
             to
             the
             Pressure
             and
             weight
             of
             twenty
             nine
             inches
             of
             Quick-silver
             .
          
        
         
           
             THEOREM
             XXVI
             .
          
           
             All
             Fluid
             Bodies
             have
             a
             sphere
             of
             Activity
             ,
             to
             which
             they
             are
             able
             to
             press
             up
             themselves
             ,
             or
             another
             Fluid
             ,
             and
             no
             further
             ,
             which
             is
             less
             or
             more
             ,
             according
             to
             the
             altitude
             of
             the
             pressing
             Fluid
             .
             Figure
             2.
             
          
           
             FOr
             understanding
             this
             Proposition
             ,
             let
             us
             imagine
             G
             H
             C
             D
             to
             be
             a
             Vessel
             ,
             in
             whose
             bottom
             ,
             there
             are
             five
             inches
             of
             Mercury
             E
             F
             C
             D.
             Next
             ,
             that
             above
             the
             stagnant
             Mercury
             ,
             there
             are
             thirty
             four
             foot
             of
             Water
             resting
             ,
             namely
             A
             B
             E
             F.
             Lastly
             ,
             that
             upon
             the
             surface
             of
             the
             said
             Water
             ,
             there
             is
             resting
             the
             Element
             of
             Air
             G
             H
             A
             B
             ,
             whose
             top
             G
             H
             ,
             I
             reckon
             to
             be
             about
             
             six
             thousand
             fathom
             above
             A
             B.
             Besides
             these
             ,
             let
             us
             imagine
             ,
             that
             there
             are
             here
             three
             Pipes
             ,
             open
             at
             both
             ends
             ,
             the
             first
             whereof
             C
             A
             G
             ,
             having
             it
             's
             lower
             orifice
             C
             ,
             drowned
             among
             the
             stagnant
             Mercury
             E
             F
             C
             D
             ,
             goeth
             so
             high
             ,
             that
             theu
             pper
             orifice
             goeth
             above
             the
             top
             of
             the
             Air
             G
             H.
             The
             second
             ,
             whose
             lower
             orifice
             I
             ,
             is
             only
             drowned
             among
             the
             Water
             A
             B
             E
             F
             ,
             reaches
             to
             the
             top
             of
             the
             Air
             likewise
             .
             The
             third
             ,
             whose
             open
             end
             K
             ,
             is
             above
             the
             surface
             of
             the
             VVater
             A
             N
             B
             ,
             and
             hanging
             in
             the
             open
             Air
             ,
             goeth
             likewise
             above
             the
             Atmosphere
             .
             These
             things
             being
             supposed
             ,
             we
             see
             that
             no
             Fluid
             can
             ,
             by
             its
             own
             proper
             weight
             ,
             press
             any
             part
             of
             it self
             ,
             higher
             then
             it
             's
             own
             surface
             ,
             seing
             the
             stagnant
             Mercury
             E
             F
             C
             D
             ,
             cannot
             press
             it self
             within
             the
             Pipe
             C
             G
             ,
             higher
             then
             E.
             Neither
             can
             the
             VVater
             A
             B
             E
             F
             ,
             press
             it self
             higher
             within
             the
             Pipe
             I
             L
             ,
             then
             the
             point
             N.
             Lastly
             ,
             neither
             can
             the
             Air
             G
             H
             A
             B
             ,
             press
             it self
             within
             the
             Pipe
             K
             M
             ,
             higher
             then
             M.
             But
             when
             one
             Fluid
             presseth
             upon
             another
             ,
             as
             the
             VVater
             A
             B
             E
             F
             ,
             upon
             the
             Mercury
             E
             F
             C
             D
             ,
             then
             doth
             the
             said
             Mercury
             ascend
             higher
             than
             it
             's
             own
             surface
             ,
             namely
             from
             E
             to
             O
             ,
             which
             point
             is
             the
             highest
             ,
             to
             which
             the
             thirty
             four
             foot
             of
             VVater
             A
             B
             E
             F
             ,
             can
             raise
             the
             Mercury
             ,
             which
             altitude
             ,
             is
             twenty
             nine
             inches
             above
             the
             surface
             E
             I
             F.
             But
             if
             a
             second
             Fluid
             be
             superadded
             ,
             as
             the
             whole
             Air
             G
             H
             A
             B
             ,
             then
             must
             the
             Mercury
             ,
             according
             to
             that
             new
             Pressure
             ,
             rise
             by
             proportion
             ;
             so
             rises
             the
             Mercury
             from
             O
             to
             P
             ,
             other
             twenty
             nine
             inches
             .
             By
             this
             same
             additional
             weight
             of
             Air
             ,
             the
             Water
             rises
             thirty
             four
             foot
             in
             the
             Pipe
             I
             L
             ,
             namely
             from
             N
             to
             R.
             Now
             ,
             I
             say
             ,
             the
             outmost
             and
             highest
             point
             ,
             to
             which
             the
             Element
             of
             Air
             G
             H
             A
             B
             can
             raise
             the
             Mercury
             ,
             is
             from
             O
             to
             P
             ;
             for
             by
             the
             Pressure
             of
             the
             Water
             
             A
             B
             E
             F
             ,
             it
             rises
             from
             E
             to
             O.
             And
             the
             highest
             point
             ,
             to
             which
             the
             said
             Air
             can
             raise
             the
             VVater
             ,
             is
             from
             N
             to
             R.
             The
             reasons
             of
             these
             determinate
             altitudes
             ,
             must
             be
             sought
             for
             ,
             from
             the
             altitudes
             of
             the
             incumbing
             and
             pressing
             Fluids
             :
             for
             as
             these
             are
             less
             or
             more
             ,
             so
             is
             the
             altitude
             of
             the
             Mercury
             ,
             and
             of
             the
             VVater
             within
             the
             Pipes
             more
             or
             less
             .
             The
             hight
             therefore
             of
             the
             Mercury
             E
             O
             ,
             is
             twenty
             nine
             inches
             ,
             because
             the
             deepness
             of
             the
             pressing
             water
             A
             B
             E
             F
             is
             thirty
             four
             foot
             .
             And
             the
             hight
             of
             the
             VVater
             N
             R
             ,
             is
             thirty
             four
             foot
             ,
             because
             the
             hight
             of
             the
             Air
             G
             H
             ,
             above
             A
             B
             ,
             is
             six
             thousand
             fathom
             ,
             or
             thereabout
             .
             And
             for
             the
             same
             reason
             ,
             is
             the
             Mercury
             O
             P
             twenty
             nine
             inches
             .
          
        
         
           
             THEOREM
             XXVII
             .
          
           
             A
             lighter
             Fluid
             ,
             is
             able
             to
             press
             with
             as
             great
             burden
             ,
             as
             a
             heavier
             .
             Figure
             2.
             
          
           
             THis
             Proposition
             is
             true
             ,
             not
             only
             of
             VVater
             in
             respect
             of
             Mercury
             ,
             but
             of
             Air
             in
             respect
             of
             them
             both
             :
             for
             albeit
             Air
             be
             a
             thousand
             times
             lighter
             then
             VVater
             ,
             yet
             may
             it
             have
             as
             great
             a
             Pressure
             with
             it
             ,
             as
             VVater
             ;
             as
             is
             evident
             from
             this
             second
             Schematism
             ,
             where
             by
             the
             Pressure
             of
             the
             outward
             Air
             G
             H
             A
             B
             ,
             twenty
             nine
             inches
             of
             Mercury
             O
             P
             are
             supported
             ,
             as
             well
             as
             the
             twenty
             nine
             inches
             E
             O
             ,
             by
             the
             Pressure
             of
             the
             VVater
             A
             B
             E
             F.
             So
             doth
             the
             same
             Air
             ,
             sustain
             the
             thirty
             four
             foot
             of
             VVater
             N
             R
             ,
             which
             are
             really
             as
             heavy
             ,
             as
             the
             twenty
             nine
             inches
             of
             Mercury
             O
             P.
             Now
             ,
             if
             the
             weight
             of
             the
             Atmosphere
             ,
             be
             equivalent
             to
             the
             
             weight
             of
             thirty
             four
             foot
             of
             Water
             ,
             or
             of
             twenty
             nine
             inches
             of
             Mercury
             ,
             't
             is
             no
             wonder
             to
             see
             Water
             press
             with
             as
             great
             weight
             as
             Mercury
             ;
             which
             is
             likewise
             clea●
             from
             this
             same
             Figure
             ,
             where
             by
             the
             Pressure
             of
             the
             Water
             A
             B
             E
             F
             ,
             twenty
             nine
             inches
             of
             Mercury
             E
             O
             are
             suspended
             ,
             as
             truly
             as
             the
             Mercury
             C
             E
             ,
             within
             the
             lower
             end
             of
             the
             Pipe
             ,
             is
             supported
             by
             the
             outward
             invironing
             Mercury
             .
             The
             reasons
             of
             these
             Phenomena
             ,
             are
             taken
             from
             the
             altitudes
             of
             the
             pressing
             Fluids
             :
             for
             though
             a
             Body
             were
             never
             so
             light
             ,
             yet
             multiplication
             of
             parts
             makes
             multiplication
             of
             weight
             ;
             which
             multiplication
             of
             parts
             in
             Fluids
             ,
             must
             be
             according
             to
             altitude
             :
             for
             multiplication
             of
             parts
             according
             to
             thickness
             and
             breadth
             will
             not
             do
             it
             .
             Observe
             here
             ,
             that
             if
             as
             much
             Air
             ,
             as
             fills
             the
             Tub
             between
             N
             and
             L
             ,
             were
             put
             into
             the
             scale
             of
             a
             Ballance
             ,
             it
             would
             exactly
             counterpoise
             the
             thirty
             four
             foot
             of
             Water
             N
             R
             ,
             poured
             into
             the
             other
             scale
             .
             Item
             ,
             that
             as
             much
             Water
             as
             will
             fill
             the
             Tub
             between
             E
             and
             A
             ,
             is
             just
             the
             weight
             of
             the
             Mercury
             E
             O.
             Lastly
             ,
             that
             as
             much
             Air
             as
             will
             fill
             the
             Pipe
             ,
             between
             O
             and
             G
             ,
             is
             just
             the
             weight
             of
             the
             Mercury
             O
             P.
             
          
        
         
           
             THEOREM
             XXVIII
             .
          
           
             The
             Pressure
             of
             Fluids
             ,
             doth
             not
             diminish
             ,
             while
             you
             subtract
             from
             their
             thickness
             ,
             but
             only
             ,
             when
             you
             subtract
             from
             their
             altitude
             .
             Figure
             1.
             
          
           
             FOr
             understanding
             this
             ,
             let
             us
             look
             upon
             the
             first
             Schematism
             ,
             where
             there
             are
             four
             Pillars
             of
             Water
             .
             Now
             I
             say
             ,
             though
             you
             cut
             off
             the
             three
             Columes
             of
             Water
             ,
             upon
             the
             right
             side
             ,
             yet
             there
             shall
             remain
             as
             much
             Pressure
             ,
             
             in
             the
             quadrat
             foot
             of
             VVater
             Q
             ,
             as
             was
             ,
             while
             these
             were
             intire
             .
             But
             if
             you
             cut
             off
             from
             the
             top
             ,
             the
             VVater
             E
             F
             G
             H
             ,
             then
             presently
             an
             alteration
             follows
             ,
             not
             only
             in
             the
             lowest
             parts
             ,
             nigh
             to
             the
             bottom
             ,
             but
             through
             all
             the
             intermediat
             parts
             :
             for
             not
             only
             the
             VVater
             Q
             loseth
             a
             degree
             of
             its
             Pressure
             ,
             but
             the
             VVaters
             P
             and
             O
             suffer
             the
             same
             loss
             .
             This
             Theorem
             holds
             true
             likewise
             in
             order
             to
             the
             Element
             of
             Air.
             For
             if
             by
             
               Divine
               Providence
            
             ,
             the
             Air
             should
             become
             less
             in
             Altitude
             ,
             than
             it
             is
             ;
             then
             surely
             ,
             the
             Bensil
             of
             the
             ambient
             Air
             ,
             that
             we
             breath
             in
             and
             out
             ,
             should
             be
             by
             proportion
             weakned
             also
             .
             And
             contrariwise
             ,
             if
             the
             Altitude
             became
             more
             ,
             then
             stronger
             should
             the
             Bensil
             be
             here
             ,
             with
             us
             ,
             in
             the
             lowest
             parts
             :
             both
             which
             would
             be
             hurtful
             to
             creatures
             ,
             that
             live
             by
             breathing
             .
             For
             if
             the
             Altitude
             of
             the
             Air
             ,
             were
             far
             more
             then
             it
             is
             ,
             our
             bodies
             would
             be
             under
             a
             far
             greater
             Pressure
             ,
             which
             surely
             would
             be
             very
             hurtful
             .
             And
             upon
             the
             other
             hand
             ,
             if
             the
             Altitude
             of
             the
             Air
             ,
             were
             far
             less
             then
             it
             is
             ,
             we
             should
             be
             at
             a
             greater
             loss
             ;
             for
             then
             ,
             by
             reason
             of
             the
             weak
             Bensil
             ,
             we
             would
             breath
             indeed
             ,
             but
             with
             great
             difficulty
             .
          
        
         
           
             THEOREM
             XXIX
             .
          
           
             A
             thicker
             Pillar
             of
             a
             Fluid
             ,
             is
             not
             able
             to
             press
             up
             a
             slenderer
             ,
             unless
             there
             be
             an
             unequal
             Pressure
             .
             Figure
             3.
             
          
           
             FOr
             understanding
             this
             ,
             let
             us
             suppose
             this
             third
             Schematism
             to
             represent
             a
             vessel
             with
             VVater
             in
             it
             ,
             as
             high
             as
             A
             B
             ,
             among
             which
             is
             thrust
             down
             to
             the
             bottom
             ,
             the
             Pipe
             G
             H
             ,
             open
             at
             both
             ends
             .
             I
             say
             then
             ,
             the
             two
             thicker
             
             Pillars
             of
             Air
             E
             A
             ,
             and
             F
             B
             ,
             pressing
             upon
             the
             surface
             of
             the
             VVater
             A
             B
             ,
             are
             not
             able
             to
             press
             up
             the
             Water
             H
             I
             ,
             or
             the
             slender
             Pillar
             of
             Air
             I
             G
             within
             the
             Pipe
             ,
             the
             one
             higher
             then
             I
             ,
             the
             other
             higher
             then
             G.
             If
             it
             be
             said
             ,
             they
             are
             heavier
             ,
             because
             they
             are
             thicker
             .
             I
             answer
             ,
             they
             are
             truly
             heavier
             ,
             for
             the
             Pillar
             of
             Air
             F
             B
             apart
             ,
             will
             be
             thrice
             as
             heavy
             ,
             as
             the
             slender
             Pillar
             of
             Air
             I
             G.
             But
             ,
             if
             you
             reckon
             the
             Pillar
             of
             Air
             E
             A
             ,
             upon
             the
             left
             hand
             ,
             both
             together
             ,
             will
             be
             six
             times
             heavier
             ,
             then
             the
             Air
             I
             G
             :
             yet
             are
             they
             not
             able
             ,
             either
             severally
             ,
             or
             conjunctly
             ,
             to
             press
             up
             the
             Water
             H
             I
             ,
             higher
             then
             I
             ,
             or
             the
             Air
             I
             G
             ,
             higher
             then
             G.
             For
             solving
             this
             difficulty
             ,
             I
             must
             say
             conform
             to
             the
             fourth
             Theorem
             ,
             that
             Fluid
             Bodies
             ,
             counterpoiseth
             one
             another
             ,
             not
             according
             to
             their
             thickness
             ,
             and
             breadth
             ,
             but
             according
             to
             their
             altitude
             only
             :
             therefore
             ,
             seing
             the
             slender
             Pillar
             of
             Air
             I
             G
             ,
             is
             as
             high
             ,
             as
             either
             F
             B
             ,
             or
             E
             A
             ,
             it
             cannot
             be
             prest
             up
             by
             them
             .
             For
             by
             vertue
             of
             this
             equal
             hight
             ,
             all
             the
             three
             press
             equally
             and
             uniformly
             ,
             upon
             the
             surface
             of
             Water
             A
             B
             ;
             and
             therefore
             according
             to
             the
             twelfth
             Theorem
             ,
             there
             can
             be
             no
             motion
             .
             But
             if
             so
             be
             ,
             the
             Pillar
             F
             B
             ,
             were
             higher
             then
             the
             Pillar
             I
             G
             ,
             then
             surely
             would
             the
             Water
             H
             I
             ,
             be
             prest
             up
             ;
             for
             in
             such
             a
             case
             ,
             there
             is
             an
             unequal
             Pressure
             .
             Or
             if
             the
             Pillar
             I
             G
             ,
             were
             higher
             then
             the
             Pillar
             F
             B
             ,
             then
             surely
             would
             the
             Water
             I
             H
             be
             prest
             down
             ,
             there
             being
             again
             an
             unequal
             Pressure
             :
             the
             Water
             within
             the
             Pipe
             ,
             being
             more
             burdened
             then
             the
             Water
             about
             the
             Pipe.
             In
             a
             word
             ,
             there
             's
             no
             more
             difficulty
             here
             ,
             then
             if
             the
             Pipe
             were
             taken
             away
             :
             in
             which
             case
             ,
             there
             would
             be
             but
             one
             Pillar
             of
             Air
             ,
             resting
             upon
             the
             surface
             of
             Water
             A
             B.
             If
             it
             be
             said
             ,
             the
             Pipe
             being
             thrust
             down
             ,
             makes
             of
             one
             Pillar
             ,
             three
             distinct
             ones
             ,
             and
             
             consequently
             a
             formal
             counter-ballance
             ,
             or
             mutual
             sustentation
             .
             Be
             it
             so
             ,
             yet
             because
             all
             these
             press
             uniformly
             ,
             there
             can
             be
             no
             motion
             .
          
        
         
           
             THEOREM
             XXX
             .
          
           
             Fluids
             press
             not
             only
             according
             to
             perpendicular
             Lines
             ,
             but
             according
             to
             crooked
             Lines
             .
             Figure
             4.
             
          
           
             FOr
             proving
             this
             Proposition
             ,
             let
             us
             suppose
             A
             B
             C
             D
             ,
             to
             be
             a
             large
             Vessel
             full
             of
             VVater
             ,
             as
             high
             as
             A
             N
             B
             ,
             and
             a
             little
             Vessel
             lying
             within
             it
             ,
             near
             to
             the
             bottom
             ,
             closs
             above
             at
             M
             ,
             but
             with
             an
             open
             orifice
             downward
             ,
             as
             G
             ,
             and
             having
             other
             two
             passages
             going
             in
             to
             it
             ,
             upon
             the
             right
             ,
             and
             left
             side
             ,
             as
             E
             O
             ,
             and
             F
             P.
             Now
             ,
             I
             say
             ,
             the
             Pressure
             of
             this
             VVater
             ,
             is
             not
             only
             from
             N
             to
             M
             ,
             in
             a
             Straight
             line
             downwards
             ,
             but
             from
             E
             to
             O
             ,
             and
             from
             F
             to
             P
             ,
             by
             crooked
             lines
             .
             Nay
             ,
             put
             the
             case
             this
             Vessel
             had
             no
             passage
             in
             to
             it
             ,
             but
             by
             a
             Labyrinth
             ,
             or
             entry
             full
             of
             intricate
             windings
             ,
             yet
             the
             Pressure
             will
             be
             communicated
             ,
             thorow
             all
             these
             ,
             even
             to
             the
             middle
             of
             it
             :
             and
             which
             is
             more
             ,
             the
             VVater
             H
             or
             I
             ,
             within
             the
             Vessel
             ,
             would
             be
             under
             the
             same
             degree
             of
             Pressure
             ,
             with
             the
             VVater
             E
             or
             L
             ,
             without
             ,
             or
             with
             the
             VVater
             K
             or
             F.
             And
             which
             is
             strange
             ,
             let
             us
             suppose
             both
             the
             entries
             E
             and
             F
             stopped
             ,
             and
             nothing
             remaining
             open
             ,
             but
             the
             hole
             G
             ,
             which
             I
             judge
             no
             wider
             ,
             then
             may
             admit
             the
             hair
             of
             ones
             head
             ,
             yet
             thorow
             that
             smal
             hole
             ,
             shall
             the
             Pressure
             be
             communicated
             ,
             to
             the
             parts
             of
             the
             Water
             within
             ,
             in
             as
             high
             a
             degree
             ,
             as
             if
             the
             upper
             part
             of
             the
             Vessel
             E
             M
             L
             ,
             were
             cut
             off
             ,
             to
             let
             the
             Pressure
             come
             down
             directly
             .
             What
             is
             true
             
             in
             order
             to
             Water
             ,
             the
             same
             is
             true
             in
             order
             to
             Air
             ,
             or
             Mercury
             ,
             or
             any
             other
             Fluid
             .
             For
             ,
             though
             a
             house
             were
             built
             never
             so
             closs
             ,
             without
             door
             ,
             or
             window
             ,
             yet
             if
             there
             remain
             but
             one
             smal
             hole
             in
             it
             ,
             the
             Pressure
             of
             the
             whole
             Atmosphere
             ,
             shall
             be
             transmitted
             thorow
             that
             entrie
             ,
             and
             shall
             reduce
             the
             Air
             within
             the
             house
             ,
             to
             as
             high
             a
             degree
             of
             Bensil
             ,
             as
             the
             Air
             without
             .
          
        
         
           
             THEOREM
             XXXI
             .
          
           
             The
             Pressure
             ,
             and
             Bensil
             of
             a
             Fluid
             ,
             that
             's
             in
             the
             Lowest
             foot
             ,
             is
             equivalent
             to
             the
             weight
             of
             the
             whole
             Pillar
             above
             .
             Figure
             5.
             
          
           
             FOr
             understanding
             this
             Proposition
             ,
             let
             us
             suppose
             E
             F
             to
             be
             the
             lowest
             foot
             of
             a
             Pillar
             of
             Air
             ,
             cut
             off
             from
             the
             rest
             ,
             and
             inclosed
             in
             the
             Vessel
             E
             F
             ,
             six
             inches
             in
             Diameter
             ,
             or
             wideness
             ,
             and
             twelve
             inches
             high
             .
             Now
             I
             say
             ,
             the
             Bensil
             and
             Pressure
             ,
             that
             's
             in
             that
             one
             foot
             of
             Air
             ,
             is
             exactly
             of
             as
             great
             force
             and
             power
             ,
             as
             is
             the
             weight
             of
             the
             whole
             Pillar
             of
             Air
             ,
             from
             which
             it
             was
             cut
             off
             .
             Let
             A
             B
             be
             that
             Pillar
             of
             Air
             ,
             which
             I
             suppose
             is
             six
             inches
             thick
             ,
             and
             six
             thousand
             fathom
             high
             .
             Take
             it
             ,
             and
             weigh
             it
             in
             a
             Ballance
             ,
             and
             say
             it
             weighs
             500
             pound
             ,
             yet
             the
             Pressure
             ,
             and
             Bensil
             ,
             that
             's
             in
             the
             Air
             E
             F
             ,
             is
             of
             as
             much
             force
             :
             and
             if
             the
             one
             be
             of
             strength
             by
             its
             weight
             ,
             to
             move
             ,
             
               v.
               g.
            
             a
             great
             Clock
             ,
             the
             other
             by
             its
             Bensil
             ,
             will
             be
             of
             as
             much
             .
             This
             proposition
             is
             true
             also
             in
             order
             to
             Water
             .
             For
             put
             the
             case
             E
             F
             ,
             were
             the
             lowest
             of
             34
             foot
             of
             Water
             :
             in
             it
             will
             be
             found
             as
             much
             Pressure
             ,
             and
             force
             ,
             as
             will
             be
             equivalent
             to
             the
             weight
             of
             the
             whole
             thirty
             three
             foot
             ,
             from
             which
             
             it
             was
             cut
             off
             .
             But
             here
             occurreth
             a
             difficulty
             ;
             for
             if
             the
             Pressure
             ,
             and
             Bensil
             of
             the
             foot
             of
             Air
             E
             F
             ,
             be
             equivalent
             to
             the
             weight
             of
             the
             whole
             Pillar
             of
             Air
             A
             B
             ,
             which
             weighs
             500
             pound
             ,
             then
             must
             the
             slender
             Pillar
             of
             Air
             C
             D
             ,
             that
             's
             but
             two
             inches
             in
             diameter
             ,
             be
             as
             heavy
             weighed
             in
             a
             ballance
             ,
             as
             the
             thicker
             Pillar
             A
             B
             ,
             which
             is
             absurd
             .
             I
             prove
             the
             connexion
             of
             the
             two
             parts
             of
             the
             Argument
             thus
             :
             as
             the
             Bensil
             of
             the
             Air
             G
             H
             ,
             is
             to
             the
             Bensil
             of
             the
             Air
             E
             F
             ,
             so
             is
             the
             weight
             of
             the
             Pillar
             C
             D
             ,
             to
             the
             weight
             of
             the
             Pillar
             A
             B
             :
             but
             so
             it
             is
             ,
             that
             the
             Bensil
             of
             the
             Air
             G
             H
             ,
             is
             equal
             in
             degree
             to
             the
             Bensil
             of
             the
             Air
             E
             F
             ,
             according
             to
             the
             Theorem
             21.
             
             Where
             it
             's
             said
             ,
             that
             the
             Pressure
             of
             Fluids
             may
             be
             as
             much
             ,
             in
             the
             least
             part
             ,
             as
             in
             the
             whole
             :
             therefore
             the
             Pillar
             C
             D
             ,
             and
             the
             Pillar
             A
             B
             ,
             must
             be
             of
             equal
             weight
             ,
             when
             both
             are
             weighed
             together
             in
             the
             opposite
             scales
             of
             a
             Ballance
             ,
             which
             is
             false
             ,
             seing
             the
             one
             is
             far
             thicker
             ,
             and
             so
             heavier
             then
             the
             other
             .
             There
             's
             no
             way
             to
             answer
             this
             objection
             ,
             but
             by
             granting
             the
             Air
             G
             H
             ,
             and
             E
             F
             ,
             to
             be
             equal
             in
             Bensil
             ,
             and
             yet
             the
             two
             Pillars
             unequal
             in
             weight
             ,
             because
             according
             to
             the
             22
             Theorem
             ,
             the
             Bensil
             of
             a
             Fluid
             is
             one
             thing
             ,
             and
             the
             
               natural
               weight
            
             is
             another
             .
          
        
         
           
             THEOREM
             XXXII
             .
          
           
             In
             all
             Fluids
             there
             is
             a
             Pondus
             and
             a
             Potentia
             ,
             a
             weight
             and
             a
             power
             ,
             counterpoising
             one
             another
             ,
             as
             in
             the
             Staticks
             .
          
           
             THat
             part
             of
             the
             Mathematicks
             ,
             which
             is
             called
             Staticks
             ,
             is
             nothing
             else
             ,
             but
             the
             
               Art
               of
               weighing
               heavy
               Bodies
            
             ;
             in
             which
             ,
             two
             things
             are
             commonly
             distinguished
             ,
             
             viz.
             the
             pondus
             and
             the
             potentia
             ,
             the
             weight
             and
             the
             power
             .
             'T
             is
             evident
             ,
             while
             two
             things
             are
             counterpoising
             one
             another
             in
             the
             opposite
             scales
             of
             a
             Ballance
             ,
             as
             Lead
             and
             Gold
             ,
             the
             one
             being
             the
             pondus
             ,
             the
             other
             the
             potentia
             .
             The
             same
             two
             are
             as
             truly
             found
             in
             the
             Hydrostaticks
             :
             for
             while
             the
             Mercurial
             Cylinder
             is
             suspended
             in
             the
             
               Torricellian
               Experiment
            
             ,
             by
             the
             weight
             of
             the
             Air
             ,
             the
             one
             is
             really
             the
             pondus
             ,
             the
             other
             the
             potentia
             .
             Or
             while
             into
             a
             Siphon
             ,
             with
             the
             two
             orifices
             upward
             ,
             Water
             is
             poured
             ,
             there
             arises
             a
             counterpoise
             ,
             the
             Water
             of
             the
             one
             Leg
             counter-ballancing
             the
             Water
             of
             the
             other
             ;
             this
             taking
             the
             name
             of
             a
             pondus
             ,
             the
             other
             the
             name
             of
             a
             potentia
             .
             'T
             is
             evident
             also
             ,
             while
             a
             surface
             of
             Water
             ,
             sustains
             a
             Pillar
             of
             Water
             ,
             this
             being
             the
             pondus
             ,
             that
             the
             potentia
             :
             Or
             ,
             while
             a
             surface
             of
             Water
             sustains
             a
             Pillar
             of
             Air
             ,
             the
             Pillar
             of
             Air
             being
             the
             pondus
             ,
             and
             the
             surface
             of
             Water
             the
             potentia
             .
             Or
             ,
             while
             a
             surface
             of
             Quick-silver
             sustains
             a
             Pillar
             of
             Water
             or
             Air
             ;
             the
             surface
             is
             the
             power
             ,
             and
             either
             of
             the
             two
             is
             the
             pondus
             ,
             or
             weight
             ,
             as
             you
             please
             .
          
        
         
           
             THEOREM
             XXXIII
             .
          
           
             Fluid
             Bodies
             can
             never
             cease
             from
             motion
             ,
             so
             long
             as
             the
             pondus
             exceeds
             the
             potentia
             ,
             or
             the
             potentia
             the
             pondus
             .
          
           
             THis
             is
             a
             sure
             Principle
             in
             the
             Hydrostaticks
             ,
             which
             will
             appear
             most
             evident
             ;
             while
             we
             pass
             thorow
             the
             subsequent
             Experiments
             ,
             I
             shall
             only
             now
             make
             it
             appear
             by
             one
             instance
             ,
             though
             afterwards
             by
             a
             hundred
             .
             In
             the
             
               Torricellian
               Experiment
            
             ,
             lately
             mentioned
             ,
             't
             is
             observed
             ,
             
             that
             though
             the
             Pipe
             were
             never
             so
             long
             ,
             that
             's
             filled
             with
             Mercury
             ,
             yet
             the
             Liquor
             subsides
             ,
             and
             falls
             down
             alwayes
             till
             it
             come
             twenty
             nine
             inches
             above
             the
             surface
             of
             the
             stagnant
             Mercury
             below
             .
             The
             reason
             whereof
             is
             truly
             this
             ,
             so
             long
             as
             the
             Mercury
             is
             higher
             then
             the
             said
             point
             ,
             as
             long
             doth
             the
             pondus
             of
             it
             exceed
             the
             potentia
             of
             the
             Air
             ;
             therefore
             the
             motion
             of
             it
             downward
             can
             never
             cease
             ,
             till
             at
             last
             by
             falling
             down
             ,
             and
             becoming
             shorter
             ,
             it
             becomes
             lighter
             ,
             in
             which
             instant
             of
             time
             ,
             the
             motion
             ends
             ,
             both
             of
             them
             being
             now
             in
             equipondia
             ,
             or
             in
             evenness
             of
             weight
             .
          
        
         
           
             THEOREM
             XXXIV
             .
          
           
             When
             two
             Fluids
             of
             different
             kinds
             are
             in
             aequilibrio
             together
             ,
             the
             height
             of
             the
             one
             Cylinder
             is
             in
             proportion
             to
             the
             height
             of
             the
             other
             ,
             〈◊〉
             the
             natural
             weight
             of
             the
             one
             is
             to
             the
             natural
             weight
             of
             the
             other
             .
          
           
             FOr
             understanding
             this
             Theorem
             ,
             we
             must
             consider
             ,
             that
             when
             two
             Cylinders
             of
             the
             same
             kind
             ,
             as
             one
             of
             Water
             with
             Water
             ,
             or
             as
             one
             of
             Mercury
             with
             Mercury
             ,
             are
             counterpoising
             one
             another
             ,
             both
             are
             of
             the
             same
             altitude
             ,
             because
             both
             are
             of
             the
             same
             natural
             weight
             .
             But
             when
             the
             two
             are
             of
             different
             kinds
             ,
             as
             a
             Cylinder
             of
             Air
             with
             Mercury
             ,
             or
             as
             a
             Cylinder
             of
             Air
             with
             Water
             ,
             or
             as
             a
             Cylinder
             of
             Water
             with
             Mercury
             ,
             then
             it
             will
             be
             found
             ,
             that
             by
             what
             proportion
             ,
             the
             one
             Liquor
             is
             naturally
             heavier
             or
             lighter
             ,
             then
             the
             other
             ,
             by
             that
             same
             proportion
             ,
             is
             the
             one
             Cylinder
             higher
             or
             lower
             then
             the
             other
             .
             For
             example
             ,
             because
             Air
             is
             reckoned
             14000
             times
             lighter
             then
             Quick-silver
             ,
             therefore
             the
             Pillar
             of
             Air
             that
             counterpoiseth
             
             the
             Pillar
             of
             Quick-silver
             in
             the
             
               Torricellian
               Experiment
            
             ,
             is
             14000
             times
             higher
             .
             The
             one
             is
             29
             inches
             ,
             and
             therefore
             the
             other
             is
             406000
             inches
             :
             which
             will
             amount
             to
             33833
             foot
             ,
             or
             about
             6766
             fathom
             ,
             counting
             five
             foot
             to
             a
             fathom
             .
             And
             because
             Air
             is
             counted
             1000
             times
             lighter
             then
             Water
             ,
             therefore
             the
             Pillar
             of
             Air
             that
             sustains
             the
             Pillar
             of
             Water
             is
             1000
             times
             higher
             .
             The
             hight
             of
             Water
             by
             the
             Pressure
             of
             the
             Air
             is
             34
             foot
             ,
             and
             therefore
             the
             hight
             of
             the
             Air
             is
             a
             thousand
             times
             34
             foot
             .
             And
             because
             Water
             is
             reckoned
             14
             times
             lighter
             than
             Mercury
             ,
             therefore
             you
             will
             find
             ,
             even
             by
             experience
             ,
             that
             the
             Pillar
             of
             Water
             ,
             that
             counterpoises
             the
             Pillar
             of
             Mercury
             ,
             is
             14
             times
             higher
             .
             For
             if
             the
             Mercury
             be
             ten
             inches
             ,
             the
             Water
             will
             be
             exactly
             140.
             
             If
             it
             be
             29
             inches
             ,
             the
             Water
             will
             be
             thirty
             four
             foot
             .
             The
             reason
             is
             evident
             ,
             because
             if
             one
             inch
             of
             Mercury
             be
             as
             heavy
             naturally
             as
             14
             inches
             of
             Water
             ,
             it
             follows
             of
             necessity
             ,
             that
             for
             making
             of
             a
             counterpoise
             ,
             to
             every
             inch
             of
             Mercury
             ,
             there
             must
             be
             14
             of
             Water
             ,
             and
             these
             in
             altitude
             ,
             each
             one
             above
             another
             .
          
        
      
       
         
         
           Hydrostatical
           EXPERIMENTS
           ,
           For
           demonstrating
           the
           wonderful
           Weight
           ,
           Force
           ,
           and
           Pressure
           of
           the
           Water
           in
           its
           own
           Element
           .
        
         
           
             EXPERIMENT
             I.
             Figure
             6.
             
          
           
             IN
             explicating
             the
             Phenomena
             of
             the
             Hydrostaticks
             ,
             and
             in
             collecting
             speculative
             ,
             or
             practical
             conclusions
             from
             them
             ,
             I
             purpose
             to
             make
             choise
             of
             the
             plainest
             ,
             and
             most
             easie
             Experiments
             ,
             especially
             in
             the
             entry
             ,
             that
             this
             knowledge
             ,
             that
             's
             not
             very
             common
             ,
             and
             yet
             very
             useful
             ,
             may
             be
             communicated
             to
             the
             meanest
             capacities
             .
             For
             ,
             if
             at
             the
             first
             ,
             any
             mystical
             ,
             or
             abstruse
             Experiments
             ,
             should
             be
             proposed
             with
             intricate
             descriptions
             ,
             they
             would
             soon
             discourage
             ,
             and
             at
             last
             hinder
             the
             ingenuous
             Reader
             from
             making
             progress
             ,
             
             For
             ,
             if
             a
             man
             do
             not
             take
             up
             distinctly
             ,
             the
             Experiment
             it self
             first
             ,
             he
             shall
             never
             be
             able
             to
             comprehend
             next
             the
             Phenomena
             ,
             nor
             at
             last
             see
             the
             inferences
             of
             the
             conclusions
             .
             Next
             ,
             though
             some
             of
             the
             trials
             may
             seem
             obvious
             ,
             yet
             they
             afford
             excellent
             Phenomena
             ,
             by
             which
             many
             profound
             secrets
             of
             Nature
             are
             discovered
             .
             And
             if
             that
             be
             ,
             't
             is
             no
             matter
             what
             kind
             they
             be
             of
             .
             Then
             ,
             the
             grand
             design
             here
             ,
             is
             not
             to
             multiply
             bare
             ,
             and
             naked
             Experiments
             ;
             for
             that
             's
             a
             work
             to
             no
             purpose
             ,
             for
             it
             's
             like
             a
             foundation
             without
             a
             superstructure
             :
             but
             the
             intention
             is
             ,
             not
             only
             to
             describe
             such
             and
             such
             things
             ,
             but
             to
             build
             such
             and
             such
             Theorems
             upon
             them
             ,
             and
             to
             infer
             such
             and
             such
             conclusions
             ,
             as
             shall
             make
             a
             stately
             building
             ,
             and
             give
             a
             man
             in
             a
             short
             time
             a
             full
             view
             of
             this
             excellent
             Doctrine
             .
          
           
             For
             the
             first
             Experiment
             then
             ,
             prepare
             a
             Vessel
             of
             any
             quantity
             ,
             as
             A
             B
             C
             D
             ,
             near
             half
             full
             of
             Water
             ,
             whose
             surface
             is
             M
             H.
             Prepare
             also
             two
             Glass-pipes
             ,
             the
             one
             wider
             ,
             the
             other
             narrower
             ,
             open
             at
             both
             ends
             ,
             which
             must
             be
             thrust
             down
             below
             the
             Water
             ,
             first
             stopping
             the
             two
             upper
             orifices
             E
             and
             F.
             This
             done
             ,
             open
             the
             said
             orifices
             ,
             and
             you
             shall
             see
             the
             Water
             ascend
             in
             the
             wider
             to
             G
             ,
             and
             in
             the
             narrower
             to
             H.
             Now
             ,
             the
             question
             is
             ,
             What
             's
             the
             reason
             ,
             why
             the
             Water
             did
             not
             ascend
             ,
             the
             orifices
             E
             and
             F
             ,
             being
             stopped
             ,
             and
             why
             it
             ascends
             ,
             they
             being
             opened
             ?
             To
             the
             first
             part
             I
             answer
             ,
             the
             Water
             cannot
             ascend
             ,
             because
             the
             imaginary
             surface
             of
             Water
             L
             K
             is
             equally
             and
             uniformly
             prest
             :
             for
             with
             what
             weight
             the
             outward
             Water
             M
             L
             ,
             and
             H
             K
             press
             the
             said
             surface
             ,
             with
             the
             same
             weight
             ,
             doth
             the
             Air
             within
             the
             two
             Pipes
             press
             it
             .
             To
             the
             second
             part
             I
             answer
             ,
             the
             Water
             ascends
             ,
             because
             the
             same
             surface
             (
             the
             orifices
             E
             and
             F
             being
             opened
             )
             is
             unequally
             
             prest
             :
             for
             the
             outward
             Water
             M
             L
             ,
             and
             H
             K
             ,
             press
             it
             more
             ,
             then
             the
             Air
             within
             the
             Pipes
             do
             .
             The
             difficulty
             only
             is
             ,
             why
             it
             is
             equally
             prest
             ,
             the
             orifices
             E
             and
             F
             being
             stopped
             ,
             and
             why
             it
             is
             unequally
             prest
             ,
             the
             said
             orifices
             being
             once
             opened
             .
             To
             unloose
             the
             knot
             ▪
             I
             must
             shew
             the
             reason
             ,
             why
             the
             Air
             within
             the
             Pipes
             ,
             press
             the
             surface
             L
             K
             ,
             with
             as
             great
             a
             burden
             ,
             as
             the
             outward
             Water
             press
             it
             .
             For
             understanding
             this
             ,
             you
             must
             know
             ,
             that
             when
             the
             orifice
             I
             is
             thrust
             down
             below
             the
             Water
             ,
             there
             ariseth
             a
             sort
             of
             debate
             between
             the
             lower
             parts
             of
             the
             Water
             ,
             and
             the
             Air
             within
             the
             Pipes
             ,
             the
             Water
             striving
             to
             be
             in
             at
             I
             ,
             and
             the
             Air
             striving
             to
             keep
             it
             out
             :
             but
             because
             the
             Water
             is
             the
             stronger
             party
             ,
             it
             enters
             the
             orifice
             I
             ,
             and
             causeth
             the
             Air
             retire
             a
             little
             up
             ,
             one
             fourth
             part
             ,
             or
             sixth
             part
             of
             an
             inch
             ,
             above
             I
             ,
             and
             no
             more
             ,
             which
             is
             a
             real
             compression
             it
             suffers
             .
             For
             the
             orifice
             E
             being
             stopped
             ,
             hinders
             any
             more
             compression
             ,
             than
             what
             is
             said
             ;
             in
             which
             instant
             of
             time
             the
             debate
             ends
             ,
             the
             Air
             no
             more
             yeelding
             ,
             and
             the
             Water
             no
             more
             urging
             ;
             by
             which
             means
             the
             Air
             having
             obtained
             a
             degree
             of
             Bensil
             ,
             more
             then
             ordinary
             ,
             by
             the
             Pressure
             of
             that
             little
             quantity
             of
             Water
             ,
             that
             comes
             in
             at
             I
             ,
             presseth
             the
             part
             of
             the
             imaginary
             surface
             ,
             it
             rests
             upon
             ,
             with
             as
             great
             weight
             ,
             as
             the
             outward
             Water
             presseth
             the
             parts
             it
             rests
             upon
             .
             But
             when
             the
             orifice
             E
             is
             opened
             ,
             the
             outward
             water
             M
             L
             ,
             and
             H
             K
             ,
             press
             the
             imaginary
             surface
             L
             K
             more
             ,
             than
             the
             Air
             within
             the
             Pipe
             can
             do
             .
             And
             the
             reason
             is
             ,
             because
             by
             opening
             the
             orifice
             above
             ,
             the
             internal
             Air
             ,
             that
             suffered
             a
             degree
             of
             Bensil
             more
             then
             ordinary
             ,
             presently
             is
             freed
             ,
             and
             consequently
             becomes
             of
             less
             force
             ,
             and
             weight
             ;
             which
             the
             Water
             finding
             ,
             that
             hath
             a
             little
             entered
             the
             orifice
             I
             ,
             instantly
             ascends
             to
             G
             ,
             it
             being
             less
             pressed
             ,
             then
             the
             Water
             
             without
             the
             Pipe.
             Now
             the
             reason
             ,
             why
             it
             ascends
             no
             higher
             then
             G
             ,
             is
             taken
             from
             the
             equal
             Pressure
             of
             the
             Body
             that
             rests
             upon
             the
             surface
             M
             G
             H
             :
             For
             ,
             assoon
             as
             it
             comes
             that
             length
             ,
             all
             the
             parts
             of
             the
             horizontal
             Plain
             of
             Water
             ,
             is
             uniformly
             prest
             with
             the
             incumbing
             Air
             ,
             both
             within
             the
             Pipe
             ,
             and
             without
             the
             Pipe.
             The
             Water
             in
             going
             up
             ,
             cannot
             halt
             mid-way
             between
             I
             and
             G
             ,
             for
             then
             there
             should
             be
             an
             unequal
             Pressure
             in
             Fluids
             without
             motion
             ,
             which
             is
             impossible
             ;
             for
             the
             Water
             is
             still
             stronger
             then
             the
             Air
             ,
             till
             once
             it
             climb
             up
             to
             G.
             
          
           
             From
             this
             Experiment
             we
             see
             first
             ,
             that
             in
             Water
             there
             is
             a
             Pressure
             and
             Force
             ;
             because
             having
             opened
             the
             orifice
             E
             ,
             which
             is
             only
             
               causa
               per
               accidens
            
             of
             this
             motion
             ,
             the
             Water
             is
             prest
             up
             from
             I
             to
             G.
             We
             see
             secondly
             ,
             that
             Fluid
             Bodies
             ,
             can
             never
             cease
             from
             motion
             ,
             till
             there
             be
             an
             equal
             Pressure
             among
             the
             parts
             ,
             which
             is
             evident
             from
             the
             ascent
             of
             the
             Water
             from
             I
             to
             G
             ,
             which
             cannot
             halt
             in
             any
             part
             between
             I
             and
             G
             ,
             because
             of
             an
             unequal
             Pressure
             ,
             till
             it
             once
             climb
             up
             to
             G.
             We
             see
             thirdly
             ,
             that
             Fluid
             Bodies
             do
             not
             sustain
             ,
             or
             counterpoise
             one
             another
             according
             to
             their
             thickness
             and
             breadth
             ,
             but
             only
             according
             to
             their
             altitude
             ;
             because
             there
             is
             not
             here
             any
             proportion
             between
             the
             slender
             Pillar
             of
             Water
             H
             K
             within
             the
             Pipe
             ,
             and
             the
             outward
             Water
             that
             sustains
             it
             ,
             I
             mean
             as
             to
             the
             thickness
             ;
             therefore
             't
             is
             no
             matter
             ,
             whither
             the
             Glass
             Tubs
             be
             wider
             or
             narrower
             ,
             that
             are
             used
             in
             counterpoising
             Fluid
             bodies
             one
             with
             another
             .
             And
             this
             is
             the
             true
             reason
             ,
             why
             't
             is
             no
             matter
             ,
             whither
             the
             Tub
             of
             the
             Baroscope
             be
             a
             wide
             one
             ,
             or
             a
             narrow
             one
             ,
             seing
             the
             Air
             doth
             not
             counterpoise
             the
             Mercury
             ,
             according
             to
             thickness
             ,
             that
             's
             to
             say
             ,
             neither
             the
             thickness
             of
             the
             ambient
             Air
             that
             sustains
             ,
             nor
             the
             thickness
             of
             the
             Mercury
             that
             
             is
             sustained
             ,
             are
             to
             be
             considered
             ;
             but
             only
             their
             altitudes
             .
             'T
             is
             true
             ,
             the
             element
             of
             Air
             is
             fourteen
             thousand
             times
             higher
             ,
             then
             the
             Mercurial
             Cylinder
             ,
             yet
             there
             is
             a
             certain
             and
             true
             proportion
             kept
             between
             their
             heights
             ;
             so
             that
             if
             the
             element
             of
             Air
             ,
             should
             by
             
               divine
               providence
            
             become
             higher
             or
             lower
             ,
             the
             height
             of
             the
             Mercury
             would
             alter
             accordingly
             .
          
        
         
           
             EXPERIMENT
             .
             II.
             Figure
             6.
             
          
           
             TAke
             out
             of
             the
             Water
             ,
             the
             wide
             Pipe
             E
             G
             I
             ,
             and
             stopping
             the
             orifice
             I
             ,
             pour
             in
             Water
             above
             at
             E
             ,
             till
             the
             Tub
             be
             compleatly
             full
             .
             Having
             done
             this
             ,
             thrust
             down
             the
             stopped
             orifice
             I
             to
             the
             bottom
             of
             the
             Vessel
             ,
             and
             there
             open
             it
             ,
             then
             shall
             you
             see
             the
             Water
             fall
             down
             from
             E
             to
             G
             ,
             and
             there
             halt
             .
             The
             reason
             is
             taken
             from
             unequal
             Pressure
             ;
             for
             the
             Tub
             being
             full
             of
             Water
             from
             E
             to
             I
             ,
             that
             part
             of
             the
             imaginary
             surface
             ,
             upon
             which
             the
             Pillar
             of
             Water
             rests
             ,
             is
             more
             burdened
             than
             any
             other
             part
             of
             it
             ,
             namely
             more
             then
             L
             or
             K
             ;
             therefore
             seing
             one
             part
             is
             more
             burdened
             than
             another
             ,
             the
             Cylinder
             of
             Water
             that
             causeth
             the
             burden
             ,
             must
             so
             far
             fall
             down
             ,
             till
             all
             the
             parts
             be
             alike
             prest
             ,
             in
             which
             instant
             of
             time
             ,
             the
             motion
             ceaseth
             .
             This
             leads
             us
             to
             a
             clear
             discovery
             of
             the
             reason
             ,
             why
             in
             the
             Baroscope
             ,
             the
             Mercury
             falls
             from
             the
             top
             of
             the
             Tub
             of
             any
             height
             ,
             alwayes
             to
             the
             twentieth
             and
             ninth
             inch
             ,
             above
             the
             stagnant
             Quick-silver
             .
             For
             example
             ,
             fill
             the
             Pipe
             N
             Q
             ,
             which
             is
             sixty
             inches
             high
             with
             Mercury
             ,
             and
             opening
             the
             orifice
             Q
             ,
             the
             Liquor
             shall
             fall
             out
             ,
             and
             fall
             down
             from
             N
             ,
             till
             it
             rest
             at
             R
             ,
             which
             
             is
             twenty
             nine
             inch
             above
             the
             open
             orifice
             Q.
             The
             reason
             is
             the
             same
             ,
             namely
             unequal
             Pressure
             ,
             seing
             one
             part
             of
             the
             imaginary
             surface
             of
             Air
             X
             S
             ,
             upon
             which
             the
             Cylinder
             of
             Mercury
             stands
             ,
             is
             more
             burthened
             then
             the
             other
             next
             adjacent
             :
             therefore
             ,
             so
             long
             and
             so
             far
             must
             the
             Mercury
             subside
             and
             fall
             down
             ,
             till
             the
             part
             Q
             ,
             upon
             which
             the
             Basis
             of
             the
             Pillar
             rests
             ,
             be
             no
             more
             burthened
             ,
             than
             the
             rest
             of
             the
             parts
             ;
             in
             which
             instant
             of
             time
             ,
             the
             motion
             ceaseth
             ,
             and
             there
             happeneth
             an
             equal
             ballance
             ,
             between
             the
             Silver
             within
             the
             Tub
             ,
             and
             the
             Air
             without
             .
             If
             it
             be
             said
             ,
             I
             see
             a
             clear
             reason
             ,
             why
             the
             outward
             Water
             M
             L
             ,
             ought
             to
             sustain
             the
             inward
             G
             I
             ,
             but
             cannot
             see
             ,
             why
             the
             outward
             Air
             T
             Z
             S
             and
             V
             R
             X
             ,
             ought
             to
             sustain
             the
             inward
             Mercury
             R
             X
             :
             neither
             do
             I
             see
             a
             reason
             ,
             why
             it
             should
             halt
             at
             R
             ,
             as
             the
             Water
             rests
             at
             G.
             I
             answer
             ,
             though
             sense
             cannot
             perceive
             the
             one
             ,
             as
             evidently
             as
             the
             other
             ,
             yet
             the
             one
             is
             as
             sure
             as
             the
             other
             .
             For
             taking
             up
             the
             reason
             why
             it
             halts
             at
             R
             ,
             29
             inches
             above
             X
             ,
             you
             must
             remember
             ,
             from
             the
             25
             Theorem
             ,
             that
             the
             Pressure
             of
             the
             Air
             upon
             Bodies
             ,
             is
             equivalent
             to
             the
             weight
             of
             34
             foot
             of
             VVater
             perpendicularly
             ,
             or
             29
             inches
             of
             Quick-silver
             .
             The
             Pillars
             of
             Air
             then
             T
             Z
             S
             ,
             and
             V
             R
             X
             ,
             being
             as
             heavy
             each
             one
             of
             them
             ,
             as
             two
             Pillars
             of
             Mercury
             ,
             each
             one
             of
             them
             29
             inches
             high
             ,
             it
             follows
             of
             necessity
             ,
             that
             the
             Mercury
             within
             the
             Tub
             ,
             must
             be
             as
             high
             as
             R.
             'T
             is
             no
             wonder
             to
             see
             the
             Silver
             halt
             at
             R
             ,
             provided
             R
             X
             ,
             and
             Z
             S
             ,
             were
             two
             bulks
             of
             Mercury
             ,
             environing
             the
             Pipe
             ,
             as
             the
             outward
             VVater
             environs
             the
             wider
             and
             narrower
             Pipe.
             Neither
             ought
             any
             to
             wonder
             ,
             when
             the
             Silver
             falls
             down
             ,
             and
             rests
             at
             R
             ,
             nothing
             environing
             the
             Pipe
             but
             Air
             ,
             seing
             the
             Pressure
             of
             the
             Air
             is
             equivalent
             to
             the
             weight
             of
             29
             inches
             of
             Quick-silver
             .
             
             This
             Experiment
             is
             easily
             made
             :
             take
             therefore
             a
             slender
             Glass-pipe
             of
             any
             length
             ,
             beyond
             30
             inches
             ,
             open
             at
             both
             ends
             ;
             but
             the
             lower
             and
             Q
             ,
             must
             be
             drawn
             so
             small
             by
             a
             flame
             of
             a
             Lamp
             ,
             that
             the
             entry
             may
             be
             no
             wider
             ,
             than
             may
             admit
             the
             point
             of
             a
             small
             needle
             ,
             or
             the
             hair
             of
             ones
             head
             .
             Then
             stopping
             the
             said
             orifice
             ,
             pour
             in
             Mercury
             above
             at
             the
             orifice
             N
             ,
             till
             the
             Pipe
             be
             compleatly
             full
             .
             Next
             ,
             close
             the
             said
             orifice
             with
             wet
             Paper
             ,
             and
             the
             pulp
             of
             your
             finger
             ;
             and
             opening
             the
             lower
             orifice
             ,
             you
             shall
             find
             ,
             (
             which
             is
             very
             delightful
             to
             behold
             )
             the
             Mercury
             spring
             out
             ,
             like
             unto
             a
             small
             silver
             threed
             ,
             and
             falling
             down
             from
             the
             top
             N
             ,
             shall
             rest
             at
             R
             ,
             the
             motion
             ceasing
             at
             the
             narrow
             orifice
             Q.
             This
             shews
             evidently
             ,
             that
             there
             is
             not
             need
             alwayes
             of
             stagnant
             Mercury
             ,
             for
             trying
             the
             
               Torrieellian
               Experiment
            
             ;
             but
             only
             when
             the
             mouth
             of
             the
             Pipe
             below
             is
             wide
             :
             for
             being
             narrow
             ,
             the
             silver
             runs
             slowly
             out
             ,
             and
             consequently
             subsides
             slowly
             above
             ,
             and
             coming
             down
             slowly
             to
             R
             ,
             there
             rests
             .
             But
             when
             the
             mouth
             is
             wide
             below
             ,
             the
             silver
             falls
             down
             so
             quickly
             ,
             that
             it
             goes
             beyond
             R
             ,
             before
             it
             can
             recover
             it self
             ,
             which
             recovery
             would
             never
             be
             ,
             unless
             there
             were
             stagnant
             Mercury
             to
             run
             up
             again
             .
          
           
             From
             what
             is
             said
             ,
             we
             see
             first
             ,
             that
             when
             one
             part
             of
             a
             surface
             of
             Water
             or
             Air
             ,
             is
             more
             burthened
             than
             another
             ,
             the
             burthened
             part
             presently
             yeelds
             ,
             till
             it
             be
             no
             more
             burthened
             than
             the
             other
             .
             This
             is
             clear
             from
             the
             falling
             down
             of
             the
             Water
             from
             E
             to
             G
             ,
             which
             cannot
             be
             supported
             by
             the
             part
             I
             ,
             because
             more
             burthened
             than
             the
             rest
             .
             We
             see
             secondly
             ,
             that
             the
             element
             of
             Air
             ,
             rests
             upon
             the
             surfaces
             of
             all
             bodies
             with
             a
             considerable
             weight
             ;
             otherwise
             it
             could
             not
             sustain
             the
             Water
             ,
             before
             it
             fall
             down
             from
             E
             to
             G
             :
             for
             if
             it
             did
             not
             left
             upon
             the
             surface
             
             M
             H
             ,
             with
             weight
             ,
             the
             Water
             could
             never
             be
             suspended
             ;
             seing
             the
             application
             of
             the
             finger
             to
             the
             orifice
             E
             ,
             is
             only
             the
             
               accidental
               cause
            
             of
             this
             sustentation
             .
             We
             see
             thirdly
             ,
             that
             according
             to
             the
             difference
             of
             
               natural
               weight
            
             ,
             between
             two
             Fluids
             ,
             so
             is
             the
             proportion
             of
             altitudes
             between
             two
             of
             their
             Cylinders
             :
             therefore
             Air
             being
             reckoned
             14000
             times
             lighter
             then
             Mercury
             ,
             it
             followes
             that
             the
             Cylinder
             of
             Mercury
             sustained
             by
             the
             Air
             ,
             must
             be
             14000
             times
             lower
             and
             shorter
             ,
             than
             the
             Cylinder
             of
             Air
             that
             sustaines
             it
             ;
             which
             appears
             from
             this
             experiment
             to
             be
             true
             ,
             seeing
             by
             the
             Pressure
             of
             the
             Air
             ,
             which
             is
             thought
             to
             be
             about
             7000
             fathom
             high
             ,
             29
             inches
             of
             Mercury
             is
             supported
             between
             R
             and
             X.
             In
             a
             word
             ,
             if
             Air
             be
             naturally
             14000
             times
             lighter
             than
             Mercury
             ,
             which
             is
             very
             probable
             ;
             then
             must
             the
             altitude
             of
             it
             ,
             commonly
             called
             the
             Atmosphere
             ,
             be
             fourteen
             thousand
             times
             ,
             nine
             and
             twenty
             inches
             ,
             that
             is
             406000
             ,
             or
             of
             feet
             33833.
             
          
        
         
           
             EXPERIMENT
             III.
             Figure
             6.
             
          
           
             WHile
             the
             outward
             ,
             and
             inward
             Water
             are
             of
             the
             same
             altitude
             ,
             withdraw
             the
             inward
             Air
             E
             G
             by
             suction
             ,
             or
             by
             any
             other
             device
             you
             think
             fit
             ,
             and
             you
             will
             find
             the
             Water
             rise
             as
             high
             as
             E
             ,
             which
             I
             suppose
             to
             be
             34
             foot
             above
             M
             G
             H.
             The
             same
             Phenomenon
             happens
             ,
             in
             taking
             the
             Air
             out
             of
             the
             narrow
             Pipe
             F
             K.
             The
             reason
             is
             still
             unequal
             Pressure
             ;
             for
             in
             removing
             the
             Air
             ,
             that
             's
             within
             the
             Pipe
             ,
             the
             part
             of
             the
             surface
             M
             ,
             and
             the
             part
             H
             ,
             remaines
             burthened
             ,
             while
             the
             part
             G
             is
             freed
             of
             its
             burden
             :
             therefore
             this
             part
             of
             the
             surface
             ,
             being
             liberated
             
             of
             its
             burden
             ,
             that
             came
             down
             through
             the
             Pipe
             ,
             instantly
             rises
             ,
             and
             climbs
             up
             as
             far
             ,
             as
             the
             outward
             Air
             resting
             upon
             M
             and
             H
             ,
             can
             raise
             it
             ,
             which
             is
             to
             E
             34
             foot
             :
             for
             the
             Pressure
             of
             the
             Air
             upon
             the
             surfaces
             of
             all
             Waters
             ,
             according
             to
             the
             25
             Theorem
             ,
             being
             equivalent
             to
             the
             weight
             of
             34
             foot
             of
             Water
             ,
             must
             raise
             the
             said
             Water
             in
             the
             Pipe
             34
             foot
             .
             You
             do
             not
             wonder
             ,
             why
             it
             rises
             from
             I
             to
             G
             ,
             as
             in
             the
             first
             experiment
             ;
             no
             more
             ought
             you
             to
             wonder
             ,
             why
             it
             rises
             from
             G
             to
             E
             ,
             seing
             the
             weight
             of
             the
             Air
             ,
             doth
             the
             same
             thing
             ,
             that
             34
             foot
             of
             Water
             resting
             upon
             the
             surface
             M
             H
             ,
             would
             do
             .
          
           
             From
             this
             experiment
             we
             see
             first
             ,
             that
             the
             Pressure
             of
             the
             Air
             ,
             is
             the
             proper
             cause
             of
             the
             motion
             of
             Water
             ,
             up
             thorow
             Pumps
             and
             Siphons
             ,
             or
             any
             other
             instrument
             ,
             that
             's
             used
             in
             Water-works
             of
             that
             kind
             ;
             for
             if
             the
             weight
             of
             the
             Air
             ,
             resting
             upon
             the
             surface
             M
             H
             be
             the
             cause
             ,
             why
             the
             Water
             climbs
             up
             from
             G
             to
             E
             ,
             the
             same
             must
             be
             the
             cause
             ,
             why
             the
             stagnant
             Water
             followes
             the
             Sucker
             of
             the
             Pump
             ,
             while
             it
             's
             pulled
             up
             .
             And
             the
             same
             is
             the
             cause
             ,
             why
             Water
             ascends
             the
             Leg
             of
             a
             Siphon
             ,
             and
             is
             the
             cause
             ,
             why
             motion
             continues
             after
             suction
             is
             ended
             .
             We
             see
             secondly
             ,
             that
             every
             Pressing
             Fluid
             hath
             a
             
               Sphere
               of
               activity
            
             ,
             to
             which
             it
             is
             able
             to
             raise
             the
             Fluid
             ,
             that
             is
             pressed
             .
             This
             is
             evident
             in
             this
             experiment
             ,
             because
             the
             Pressure
             of
             the
             Air
             resting
             upon
             M
             H
             ,
             is
             able
             to
             raise
             the
             Water
             ,
             the
             hight
             of
             E
             in
             the
             wide
             Pipe
             ,
             and
             the
             hight
             of
             F
             in
             the
             narrow
             ,
             and
             no
             further
             ,
             even
             though
             the
             said
             Pipes
             were
             far
             longer
             :
             and
             this
             altitude
             and
             highest
             point
             is
             precisely
             34
             foot
             between
             Air
             and
             Water
             .
             We
             see
             thirdly
             ,
             that
             't
             is
             all
             one
             matter
             ,
             whether
             Pumps
             and
             Siphons
             be
             wider
             or
             narrower
             ,
             whether
             the
             tub
             of
             the
             Baroscope
             be
             ,
             wherein
             the
             Mercury
             is
             suspended
             ,
             of
             a
             large
             Diameter
             ,
             or
             of
             a
             lesser
             
             Diameter
             .
             This
             is
             also
             evident
             from
             the
             same
             experiment
             ;
             seing
             there
             is
             no
             more
             difficulty
             in
             causing
             the
             Water
             ascend
             the
             wide
             Pipe
             ,
             than
             in
             causing
             it
             ascend
             the
             narrow
             one
             .
             And
             the
             reason
             is
             ,
             because
             the
             pressing
             Fluid
             repects
             not
             the
             pressed
             Fluid
             ,
             according
             to
             its
             thickness
             and
             breadth
             ;
             but
             only
             according
             to
             its
             altitude
             .
             Therefore
             '
             its
             as
             easie
             for
             the
             Air
             ,
             to
             press
             up
             Water
             through
             a
             Pump
             four
             foot
             in
             Diameter
             ,
             as
             to
             press
             it
             up
             through
             a
             Pump
             ,
             but
             one
             foot
             in
             Diameter
             .
          
        
         
           
             EXPERIMENT
             IV.
             Figure
             7.
             
          
           
             THis
             Schematism
             represents
             a
             large
             Vessel
             full
             of
             Water
             ,
             whose
             first
             and
             visible
             surface
             is
             D
             E
             H
             K.
             The
             second
             ,
             that
             's
             imaginary
             is
             ,
             L
             I
             ,
             six
             foot
             below
             it
             .
             The
             third
             of
             the
             same
             kind
             ,
             is
             M
             G
             ,
             six
             foot
             lower
             .
             The
             fourth
             ,
             is
             N
             F
             O
             ,
             six
             foot
             yet
             lower
             .
             The
             last
             ,
             and
             lowest
             ,
             is
             A
             B
             C.
             There
             are
             here
             also
             four
             Tubs
             ,
             or
             rather
             one
             Tub
             under
             four
             divers
             positions
             ,
             with
             both
             ends
             open
             .
             After
             this
             Tub
             D
             A
             is
             thrust
             below
             the
             Water
             ,
             till
             it
             ascend
             ,
             as
             high
             as
             D
             in
             it
             ,
             lift
             it
             up
             between
             your
             fingers
             ,
             till
             it
             have
             the
             position
             of
             the
             second
             Pipe
             E
             F
             ,
             and
             then
             you
             shall
             see
             ,
             as
             the
             orifice
             of
             the
             Pipe
             ascends
             ,
             the
             Cylinder
             of
             Water
             fall
             out
             by
             little
             and
             little
             ,
             until
             it
             be
             no
             longer
             than
             E
             F.
             Again
             ,
             lift
             it
             further
             up
             ,
             till
             it
             have
             the
             position
             of
             the
             Pipe
             H
             G
             ,
             then
             shall
             you
             find
             the
             Cylinder
             of
             Water
             become
             yet
             shorter
             .
             Lastly
             ,
             if
             it
             be
             scituated
             ,
             as
             the
             Pipe
             K
             I
             the
             internal
             Water
             becomes
             no
             longer
             than
             K
             I.
             The
             reasons
             of
             these
             Phenomena
             are
             the
             same
             ;
             namely
             unequal
             Pressure
             ;
             for
             the
             Orifice
             A
             being
             lifted
             up
             as
             
             high
             as
             F
             ,
             it
             comes
             to
             the
             imaginary
             surface
             N
             O
             ,
             which
             is
             not
             under
             so
             much
             Pressure
             ,
             as
             the
             other
             is
             ;
             therefore
             one
             part
             of
             it
             being
             more
             burdened
             ,
             than
             another
             ,
             namely
             the
             part
             upon
             which
             the
             Cylinder
             of
             Water
             rests
             ,
             it
             presently
             yeelds
             ,
             and
             suffers
             the
             Cylinder
             to
             become
             shorter
             ,
             and
             lighter
             ,
             till
             it
             become
             no
             heavier
             ,
             then
             is
             proportionable
             to
             its
             own
             strength
             .
             To
             make
             this
             reason
             more
             evident
             ,
             it
             is
             to
             be
             noted
             ,
             that
             no
             surface
             of
             Water
             is
             able
             to
             support
             a
             Cylinder
             higher
             then
             its
             own
             deepness
             ,
             that
             is
             to
             say
             ,
             if
             a
             surface
             be
             40
             foot
             deep
             ,
             it
             is
             able
             to
             sustain
             a
             Cylinder
             40
             foot
             high
             ,
             and
             no
             more
             :
             therefore
             the
             surface
             N
             O
             ,
             being
             but
             18
             foot
             deep
             ,
             it
             cannot
             sustain
             a
             Cylinder
             24
             foot
             long
             :
             for
             if
             that
             were
             ,
             then
             the
             Potentia
             ,
             should
             be
             inferiour
             to
             the
             Pondus
             ,
             which
             is
             impossible
             in
             the
             Hydrostaticks
             .
             In
             effect
             ,
             it
             were
             no
             less
             absurdity
             ,
             then
             to
             say
             ,
             18
             ounces
             are
             able
             to
             counterballance
             24.
             
             For
             a
             second
             trial
             ,
             lift
             up
             the
             same
             Pipe
             higher
             ,
             till
             it
             acquire
             the
             position
             of
             the
             Tub
             G
             H
             ;
             in
             this
             case
             ,
             the
             Cylinder
             of
             Water
             within
             it
             ,
             becomes
             yet
             shorter
             ,
             even
             no
             longer
             ,
             than
             G
             H.
             The
             reason
             is
             the
             same
             ,
             namely
             unequal
             Pressure
             ;
             for
             when
             a
             Cylinder
             of
             Water
             18
             foot
             high
             ,
             comes
             to
             rest
             upon
             this
             surface
             ,
             that
             is
             but
             12
             foot
             deep
             ,
             it
             makes
             one
             part
             of
             it
             more
             burdened
             then
             another
             ;
             therefore
             the
             part
             that
             is
             more
             prest
             ,
             presently
             yeelds
             ,
             and
             suffers
             the
             Cylinder
             to
             fall
             down
             ,
             till
             the
             Pondus
             of
             it
             ,
             become
             equal
             to
             its
             own
             Potentia
             .
             For
             the
             last
             trial
             ,
             lift
             up
             the
             Tub
             ,
             till
             it
             acquire
             the
             position
             of
             the
             Pipe
             K
             I
             :
             in
             this
             case
             ,
             the
             Water
             within
             it
             becomes
             no
             longer
             then
             K
             I
             ,
             the
             surface
             L
             I
             ,
             that
             is
             but
             six
             foot
             deep
             ,
             not
             being
             able
             to
             sustain
             a
             Cylinder
             12
             foot
             high
             .
          
           
             From
             this
             Experiment
             we
             see
             first
             ,
             that
             in
             all
             Fluid
             Bodies
             there
             is
             a
             Pressure
             ,
             which
             is
             more
             or
             less
             ,
             according
             to
             
             the
             deepness
             of
             that
             Fluid
             ;
             this
             is
             evident
             from
             the
             four
             several
             surfaces
             ;
             there
             being
             more
             Pressure
             and
             force
             in
             the
             lowest
             A
             B
             C
             ,
             then
             in
             the
             next
             N
             O
             ;
             and
             more
             in
             this
             ,
             then
             in
             the
             surface
             M
             G
             ;
             and
             more
             in
             this
             ,
             then
             in
             L
             I.
             We
             see
             secondly
             ,
             that
             in
             all
             Fluids
             ,
             there
             is
             a
             Pondus
             and
             a
             Potentia
             ;
             which
             two
             are
             alwayes
             of
             equal
             force
             ,
             and
             strength
             ;
             the
             Potentia
             is
             clear
             and
             evident
             in
             the
             surface
             ,
             by
             supporting
             the
             Pillar
             ;
             which
             Pillar
             is
             nothing
             else
             ,
             but
             the
             Pondus
             supported
             .
             And
             that
             they
             are
             alwayes
             of
             equal
             strength
             ,
             is
             most
             evident
             also
             ;
             for
             when
             you
             endeavour
             to
             make
             the
             Pondus
             unequal
             to
             the
             Potentia
             ,
             in
             making
             a
             surface
             18
             foot
             deep
             ,
             to
             support
             a
             Pillar
             24
             foot
             high
             ,
             they
             of
             their
             own
             accord
             become
             equal
             ;
             the
             Pillar
             becoming
             shorter
             ,
             and
             suitable
             to
             the
             strength
             of
             the
             surface
             that
             sustains
             it
             .
             We
             see
             thirdly
             ,
             that
             't
             is
             impossible
             for
             one
             part
             of
             the
             same
             Horizontal
             surface
             ,
             to
             be
             more
             burdened
             then
             another
             :
             for
             when
             you
             endeavour
             to
             do
             it
             ,
             by
             setting
             a
             longer
             Pillar
             upon
             it
             ,
             the
             part
             burdened
             instantly
             yeelds
             ,
             till
             it
             be
             no
             more
             prest
             ,
             then
             the
             next
             part
             to
             it
             .
             We
             see
             fourthly
             ,
             that
             the
             inequality
             ,
             that
             is
             between
             the
             Pondus
             and
             the
             Potentia
             in
             Fluids
             ,
             is
             the
             proper
             cause
             of
             the
             motion
             of
             Fluids
             .
             For
             when
             you
             endeavour
             to
             make
             a
             surface
             30
             foot
             deep
             ,
             sustain
             a
             Pillar
             40
             foot
             high
             ,
             this
             inequality
             is
             the
             true
             cause
             ,
             why
             the
             Pillar
             subsides
             ,
             and
             falls
             down
             ,
             and
             why
             the
             surface
             yeelds
             ,
             and
             gives
             way
             to
             it
             .
             And
             this
             inequality
             is
             the
             true
             cause
             ,
             why
             the
             motion
             of
             Water
             thorow
             Siphons
             continues
             .
             For
             understanding
             this
             ,
             you
             must
             conceive
             a
             Siphon
             ,
             to
             be
             nothing
             else
             ,
             but
             a
             crooked
             Pipe
             with
             two
             legs
             ,
             the
             one
             drowned
             among
             Water
             ,
             the
             other
             hanging
             in
             the
             open
             Air.
             The
             use
             of
             it
             is
             ,
             for
             conveying
             Wine
             or
             Water
             from
             one
             Vessel
             to
             another
             ,
             which
             is
             easily
             done
             by
             suction
             .
             Now
             after
             suction
             is
             ended
             ,
             
             the
             motion
             of
             the
             Water
             continues
             ,
             till
             the
             surface
             become
             lower
             ,
             then
             the
             orifice
             out
             of
             which
             it
             runs
             .
             The
             true
             reason
             then
             ,
             why
             the
             Water
             flows
             out
             ,
             is
             the
             inequality
             between
             the
             Potentia
             of
             the
             Air
             ,
             and
             the
             Pondus
             of
             the
             VVater
             ;
             the
             Pondus
             being
             stronger
             then
             the
             Potentia
             .
             For
             in
             Air
             as
             in
             VVater
             ,
             we
             must
             conceive
             Horizontal
             surfaces
             ;
             and
             these
             surfaces
             to
             be
             endowed
             with
             Pressure
             and
             force
             ,
             as
             are
             the
             surfaces
             of
             VVater
             .
             Now
             when
             the
             leg
             of
             a
             Siphon
             is
             hanging
             in
             the
             Air
             ,
             it
             must
             rest
             upon
             one
             surface
             or
             another
             ,
             and
             consequently
             the
             VVater
             in
             it
             ,
             must
             rest
             upon
             the
             same
             surface
             .
             If
             the
             Potentia
             of
             the
             surface
             be
             stronger
             ,
             then
             the
             Pondus
             of
             the
             VVater
             ;
             the
             VVater
             is
             driven
             backward
             ,
             which
             alwayes
             comes
             to
             pass
             ,
             when
             the
             orifice
             is
             higher
             ,
             then
             the
             surface
             of
             the
             VVater
             of
             the
             Vessel
             ,
             among
             which
             the
             other
             leg
             is
             drowned
             .
             If
             the
             Potentia
             of
             the
             surface
             of
             that
             Air
             ,
             be
             of
             equal
             power
             and
             strength
             ,
             with
             the
             Pondus
             of
             the
             VVater
             ,
             the
             VVater
             goeth
             neither
             backward
             ,
             nor
             forward
             ,
             but
             stands
             in
             equilibrio
             :
             this
             happens
             ,
             when
             the
             orifice
             is
             neither
             higher
             ,
             nor
             lower
             ,
             than
             the
             surface
             of
             the
             VVater
             in
             the
             Vessel
             .
             But
             if
             the
             Potentia
             of
             the
             surface
             of
             the
             Air
             be
             weaker
             ,
             than
             the
             Pondus
             of
             the
             VVater
             ;
             in
             this
             case
             ,
             the
             Air
             yeelds
             ,
             and
             suffers
             the
             VVater
             to
             run
             out
             ,
             even
             as
             a
             surface
             30
             foot
             deep
             ,
             yeelds
             to
             a
             Pillar
             of
             VVater
             40
             foot
             high
             .
             The
             same
             inequality
             is
             the
             reason
             ,
             why
             VVater
             climbs
             up
             the
             Pump
             ;
             why
             VVater
             climbs
             up
             a
             Pipe
             ,
             when
             a
             man
             sucks
             with
             his
             mouth
             .
             Before
             suction
             ,
             the
             Potentia
             that
             's
             in
             the
             surface
             of
             VVater
             ,
             among
             which
             the
             end
             of
             the
             Pipe
             is
             drowned
             ,
             is
             of
             equal
             force
             with
             the
             Pondus
             of
             the
             Pillar
             of
             Air
             ,
             that
             comes
             down
             thorow
             the
             Pipe
             ,
             or
             Pump
             ;
             but
             assoon
             as
             a
             man
             begins
             to
             suck
             ,
             the
             said
             Pillar
             of
             Air
             becomes
             lighter
             ;
             and
             the
             VVater
             finding
             this
             ,
             presently
             ascends
             .
             The
             same
             
             is
             the
             reason
             ,
             why
             the
             Mercury
             falls
             down
             to
             29
             inches
             in
             the
             Baroscope
             ,
             and
             no
             further
             :
             for
             as
             long
             as
             the
             Pondus
             of
             the
             Pillar
             of
             Mercury
             ,
             exceeds
             the
             Potentia
             of
             the
             surface
             of
             Air
             ,
             so
             long
             doth
             the
             motion
             continue
             ;
             and
             when
             both
             are
             become
             equal
             in
             force
             ,
             the
             motion
             ceaseth
             .
             VVhen
             the
             Glass-tub
             is
             40
             inches
             long
             ,
             and
             filled
             with
             Mercury
             ,
             and
             inverted
             after
             the
             common
             manner
             ,
             you
             are
             endeavouring
             as
             it
             were
             ,
             to
             cause
             a
             surface
             29
             inches
             deep
             ,
             sustain
             a
             Pillar
             40
             inches
             high
             ,
             which
             is
             utterly
             impossible
             in
             Fluids
             ▪
             It
             is
             judged
             by
             many
             a
             wonder
             to
             see
             the
             deflux
             of
             the
             Mercury
             in
             the
             Baroscope
             ;
             but
             in
             effect
             ,
             there
             's
             no
             more
             cause
             of
             admiration
             in
             it
             ,
             than
             to
             see
             the
             Cylinder
             of
             Water
             grow
             shorter
             ,
             by
             lifting
             the
             Pipe
             up
             from
             one
             surface
             to
             another
             .
          
           
             From
             this
             Experiment
             ,
             we
             see
             the
             true
             reason
             ,
             why
             the
             Mercurial
             Cylinder
             of
             the
             Baroscope
             becomes
             shorter
             and
             shorter
             ,
             according
             as
             a
             man
             climbs
             up
             a
             mountain
             with
             it
             .
             For
             at
             the
             root
             of
             the
             hill
             ,
             the
             surface
             of
             Air
             ,
             that
             sustains
             the
             Pillar
             of
             Mercury
             ,
             is
             of
             greater
             force
             ,
             than
             the
             surface
             at
             the
             middle
             part
             :
             and
             this
             is
             stronger
             than
             any
             surface
             at
             the
             top
             .
             The
             Pipe
             therefore
             being
             carried
             up
             from
             one
             surface
             to
             another
             ,
             the
             Mercury
             in
             it
             ,
             must
             subside
             ,
             and
             fall
             down
             ,
             even
             as
             the
             Water
             falls
             down
             ,
             and
             becomes
             shorter
             ,
             by
             lifting
             the
             Pipe
             from
             the
             surface
             A
             B
             C
             D
             to
             the
             surface
             N
             O.
             And
             as
             the
             whole
             VVater
             would
             fall
             down
             ,
             if
             the
             orifice
             I
             ,
             were
             lifted
             above
             the
             surface
             D
             E
             H
             K
             ,
             so
             if
             the
             Baroscope
             could
             be
             carried
             so
             high
             ,
             till
             it
             came
             above
             the
             top
             of
             the
             Air
             ,
             the
             whole
             Mercurial
             Cylinder
             would
             surely
             fall
             down
             .
             And
             as
             by
             thrusting
             down
             the
             said
             Pipe
             to
             the
             bottom
             of
             the
             Vessel
             again
             ,
             as
             the
             Pipe
             D
             A
             ,
             the
             VVater
             ascends
             in
             it
             ;
             so
             by
             bringing
             down
             the
             Baroscope
             to
             the
             earth
             again
             ,
             the
             whole
             19
             inches
             would
             rise
             again
             .
          
        
         
           
           
             EXPERIMENT
             V.
             Figure
             8.
             
          
           
             FIll
             the
             Vessel
             A
             D
             G
             H
             with
             VVater
             to
             the
             brim
             .
             Next
             ,
             thrust
             down
             the
             open
             orifice
             of
             the
             Tub
             D
             A
             ,
             to
             the
             bottom
             ,
             and
             you
             shall
             see
             the
             VVater
             ascend
             in
             it
             ,
             as
             high
             as
             D
             ,
             according
             to
             the
             first
             experiment
             .
             When
             this
             is
             done
             ,
             recline
             the
             said
             Pipe
             ,
             till
             it
             ly
             as
             B
             E
             ,
             and
             you
             shall
             find
             the
             Pipe
             ,
             compleatly
             full
             of
             VVater
             .
             Next
             ,
             erect
             the
             same
             Tub
             again
             as
             D
             A
             ,
             and
             you
             shall
             see
             the
             Cylinder
             of
             VVater
             fall
             down
             ,
             and
             become
             shorter
             ,
             as
             at
             first
             .
             For
             salving
             this
             Phenomenon
             ,
             and
             such
             like
             ,
             I
             must
             suppose
             this
             VVater
             to
             be
             50
             inches
             deep
             ,
             and
             the
             Tub
             I
             A
             ,
             and
             B
             E
             90
             inches
             long
             :
             and
             the
             said
             Tub
             in
             reclining
             ,
             to
             describe
             the
             quadrant
             of
             a
             Circle
             F
             E
             G.
             Now
             the
             question
             is
             ,
             why
             there
             being
             but
             50
             inches
             of
             Water
             in
             the
             Tub
             ,
             while
             erected
             ,
             there
             should
             be
             60
             in
             it
             ,
             when
             it
             is
             reclined
             ?
             Secondly
             ,
             why
             there
             should
             be
             90
             inches
             of
             Water
             in
             the
             Tub
             B
             E
             ,
             and
             but
             50
             in
             it
             ,
             when
             it
             stands
             Perpendicular
             ,
             as
             D
             A
             ?
             If
             you
             reply
             ,
             because
             there
             are
             90
             inches
             
               in
               recta
               linea
            
             between
             the
             point
             B
             ,
             and
             the
             point
             E
             ,
             and
             but
             50
             between
             A
             and
             D.
             But
             this
             will
             not
             answer
             the
             case
             ;
             because
             ,
             if
             you
             stop
             the
             orifice
             E
             ,
             with
             the
             pulp
             of
             your
             Finger
             ,
             before
             it
             be
             erected
             ,
             you
             will
             find
             the
             Tub
             remain
             full
             of
             VVater
             ,
             even
             while
             it
             stands
             Perpendicular
             ;
             and
             fall
             down
             ,
             when
             the
             orifice
             is
             opened
             .
             Or
             ,
             while
             the
             Tub
             stands
             Perpendicular
             ,
             stop
             the
             orifice
             I
             ,
             and
             recline
             it
             as
             B
             E
             :
             yet
             no
             more
             Water
             will
             be
             found
             in
             it
             ,
             than
             50
             inches
             :
             but
             by
             unstopping
             the
             said
             orifice
             ,
             the
             VVater
             climbs
             up
             from
             R
             to
             E
             ,
             and
             becomes
             90
             inches
             .
             Now
             ,
             what
             's
             the
             reason
             ,
             
             why
             it
             runs
             up
             from
             R
             to
             E
             ,
             and
             why
             it
             falls
             down
             from
             I
             to
             D
             ?
             I
             answer
             then
             ,
             the
             VVater
             must
             run●up
             from
             R
             to
             E
             ,
             because
             of
             the
             inequality
             ,
             that
             's
             between
             the
             Pondus
             of
             the
             Cylinder
             B
             R
             ,
             and
             the
             Potentia
             of
             the
             surface
             of
             VVater
             A
             B
             C
             ,
             that
             supports
             the
             said
             Cylinder
             .
             For
             understanding
             this
             ,
             know
             ,
             while
             the
             Tub
             is
             erected
             ,
             there
             is
             a
             perfect
             equality
             ,
             between
             the
             weight
             of
             the
             Pillar
             A
             D
             ,
             and
             the
             force
             or
             Power
             of
             the
             surface
             that
             sustains
             it
             ,
             seing
             a
             surface
             50
             inches
             deep
             ,
             supports
             a
             Pillar
             50
             inches
             high
             .
             But
             assoon
             as
             the
             Tub
             is
             reclined
             ,
             there
             arises
             ane
             inequality
             between
             the
             saids
             two
             parties
             ,
             the
             Pondus
             of
             the
             Cylinder
             becoming
             now
             less
             than
             before
             .
             If
             you
             say
             the
             quantity
             of
             the
             VVater
             is
             the
             same
             ,
             namely
             50
             inches
             ,
             in
             the
             reclined
             Tub
             ,
             as
             well
             as
             in
             the
             Perpendicular
             .
             I
             grant
             the
             quantity
             is
             the
             same
             ,
             but
             the
             weight
             is
             become
             less
             .
             Now
             the
             reason
             ,
             why
             the
             same
             individual
             VVater
             ,
             is
             not
             so
             heavy
             as
             before
             ,
             is
             this
             ;
             there
             are
             40
             ounces
             of
             it
             ,
             supported
             by
             the
             sides
             of
             the
             Tub
             within
             ;
             which
             were
             not
             ,
             while
             the
             Tub
             was
             erected
             :
             for
             in
             this
             position
             ,
             the
             whole
             weight
             of
             the
             Cylinder
             rests
             upon
             the
             surface
             :
             but
             while
             the
             Tub
             is
             reclined
             ,
             the
             said
             surface
             is
             eased
             ,
             and
             freed
             of
             40
             ounces
             of
             it
             ;
             this
             40
             ,
             resting
             and
             leaning
             upon
             the
             sides
             of
             the
             Pipe
             within
             .
             The
             surface
             then
             ,
             finding
             the
             said
             Cylinder
             lighter
             now
             than
             before
             ,
             instantly
             drives
             it
             up
             from
             R
             to
             E
             ,
             40
             inches
             .
             And
             likewise
             ,
             when
             the
             reclined
             Pipe
             is
             made
             Perpendicular
             ,
             the
             Water
             falls
             down
             from
             I
             to
             D
             ,
             because
             of
             the
             inequality
             ,
             that
             's
             between
             the
             Pondus
             of
             the
             Pillar
             ,
             and
             the
             Potentia
             of
             the
             surface
             ;
             this
             surface
             50
             inches
             deep
             ,
             not
             being
             able
             to
             support
             a
             Pillar
             90
             inches
             high
             ;
             for
             if
             this
             were
             ,
             then
             one
             part
             ,
             should
             be
             more
             burthened
             than
             another
             ,
             which
             is
             impossible
             .
          
           
             It
             is
             to
             be
             observed
             ,
             that
             by
             how
             much
             the
             more
             ,
             the
             
             Tub
             is
             reclined
             from
             a
             Perpendicular
             ,
             towards
             the
             horizontal
             surface
             A
             B
             C
             ,
             by
             so
             much
             the
             more
             growes
             the
             inequality
             ,
             between
             the
             Pondus
             and
             the
             Potentia
             ,
             and
             that
             according
             to
             a
             certaine
             proportion
             .
             Hence
             is
             it
             ,
             that
             the
             Tub
             being
             reclined
             from
             60
             degrees
             to
             50
             ,
             there
             arises
             a
             greater
             inequality
             between
             the
             Pondus
             of
             the
             Cylinder
             ,
             and
             the
             Potentia
             of
             the
             surface
             ,
             than
             while
             it
             is
             reclined
             from
             70
             to
             60
             :
             and
             more
             yet
             in
             moving
             from
             50
             to
             40
             ,
             than
             in
             moving
             from
             60
             to
             50
             ,
             and
             so
             downward
             ,
             till
             it
             be
             horizontal
             ,
             in
             which
             position
             ,
             the
             whole
             Pondus
             is
             lost
             .
             And
             contrariwise
             ,
             while
             the
             Pipe
             is
             elevated
             ,
             the
             Pondus
             begins
             to
             grow
             ;
             and
             growes
             more
             ,
             being
             lifted
             up
             from
             10
             to
             20
             ,
             than
             from
             1
             to
             10
             :
             and
             yet
             more
             in
             travelling
             from
             20
             to
             30
             ,
             than
             from
             10
             to
             20
             ,
             and
             so
             upwards
             ;
             till
             it
             be
             Perpendicular
             ,
             in
             which
             position
             ,
             the
             Cylinder
             regaines
             the
             whole
             Pondus
             and
             weight
             ,
             it
             had
             .
             This
             proportion
             is
             easily
             known
             ,
             for
             it
             s
             nothing
             else
             ,
             but
             the
             proportion
             of
             
               Versed
               Sines
            
             upon
             the
             line
             F
             B
             ;
             for
             according
             to
             what
             measure
             ,
             these
             unequal
             divisions
             become
             wider
             ,
             and
             wider
             from
             90
             to
             1
             ,
             according
             to
             the
             same
             proportion
             does
             the
             Pondus
             of
             the
             Cylinder
             become
             less
             and
             less
             :
             and
             contrariwise
             ,
             according
             to
             what
             proportion
             the
             said
             divisions
             become
             more
             and
             more
             narrow
             from
             1
             to
             90
             ,
             according
             to
             the
             same
             measure
             and
             rate
             ,
             does
             the
             Pondus
             of
             the
             Cylinder
             become
             greater
             and
             greater
             .
          
           
           
        
         
           
             EXPERIMENT
             VI.
             Figure
             9.
             
          
           
             THis
             Schematism
             represents
             a
             Vessel
             fall
             of
             Water
             ,
             whose
             first
             and
             visible
             surface
             is
             H
             I
             K
             ;
             the
             second
             ,
             which
             is
             imaginary
             ,
             is
             E
             F
             G
             :
             the
             third
             ,
             A
             B
             C
             D.
             
             Besides
             these
             three
             in
             Water
             ,
             conceive
             a
             fourth
             in
             the
             Air
             ,
             above
             the
             Water
             ,
             namely
             L
             M
             N.
             Upon
             this
             aërial
             surface
             ,
             rests
             the
             orifice
             M
             ,
             of
             the
             Tub
             T
             M
             ,
             open
             above
             .
             Upon
             the
             surface
             E
             F
             G
             ,
             is
             standing
             the
             mouth
             F
             ,
             of
             the
             Pipe
             S
             F.
             And
             upon
             the
             surface
             A
             B
             C
             D
             ,
             stands
             the
             Pipe
             R
             B
             ,
             open
             at
             both
             ends
             .
             After
             the
             orifice
             B
             is
             drowned
             below
             the
             VVater
             ,
             you
             will
             find
             the
             Liquor
             rise
             from
             B
             to
             H.
             Then
             close
             with
             the
             pulp
             of
             your
             Finger
             the
             mouth
             R
             ,
             and
             lift
             the
             Pipe
             so
             far
             up
             ,
             till
             it
             have
             the
             Position
             of
             the
             Pipe
             S
             F
             ;
             and
             you
             shall
             see
             the
             VVater
             hing
             in
             it
             between
             F
             and
             O.
             Lastly
             ,
             bring
             the
             said
             orifice
             compleatly
             above
             the
             VVater
             ,
             till
             it
             have
             the
             position
             of
             the
             Tub
             T
             M
             ;
             yet
             shall
             the
             VVater
             still
             hing
             in
             it
             ,
             as
             M
             P.
             The
             first
             question
             is
             ,
             what
             sustains
             the
             VVater
             I
             O
             ;
             for
             the
             part
             F
             I
             ,
             is
             sustained
             by
             the
             ambient
             VVater
             ?
             I
             answer
             ,
             it
             cannot
             be
             the
             pulp
             of
             the
             Finger
             closing
             the
             orifice
             S
             ;
             for
             though
             ,
             by
             taking
             away
             the
             Finger
             ,
             the
             VVater
             O
             I
             falls
             down
             ,
             and
             by
             putting
             to
             the
             Finger
             ,
             it
             is
             keeped
             up
             ,
             yet
             this
             proves
             not
             the
             pulp
             of
             the
             Finger
             to
             be
             the
             principal
             ,
             and
             immediat
             cause
             .
             I
             say
             then
             ,
             the
             VVater
             O
             I
             is
             suspended
             by
             the
             weight
             of
             the
             incumbing
             Air
             ,
             resting
             upon
             the
             surface
             H
             I
             K.
             For
             understanding
             this
             ,
             consider
             ,
             as
             I
             said
             before
             ,
             25.
             
             Theorem
             ,
             that
             the
             Pressure
             of
             the
             Air
             upon
             all
             Bodies
             ,
             is
             just
             equivalent
             to
             the
             weight
             of
             34
             foot
             of
             VVater
             .
             Hence
             then
             is
             it
             ,
             that
             if
             the
             Air
             be
             able
             to
             sustain
             a
             Pillar
             of
             VVater
             ,
             34
             foot
             high
             ,
             it
             must
             be
             able
             to
             sustain
             the
             short
             Pillar
             O
             I
             ,
             that
             exceeds
             not
             four
             foot
             .
             The
             second
             question
             is
             ,
             whether
             the
             part
             F
             ,
             be
             equally
             burthened
             with
             the
             part
             E
             ,
             or
             G
             ;
             for
             it
             would
             seem
             not
             ,
             seing
             the
             VVater
             O
             I
             F
             ,
             is
             but
             four
             foot
             high
             ;
             whilest
             upon
             E
             or
             G
             is
             resting
             ,
             not
             only
             more
             then
             a
             foot
             of
             VVater
             to
             the
             top
             H
             I
             K
             ,
             but
             
             the
             whole
             weight
             of
             the
             Atmosphere
             upon
             the
             said
             top
             is
             resting
             ,
             which
             is
             equivalent
             to
             the
             burden
             of
             34
             foot
             of
             VVater
             .
             I
             answer
             ,
             there
             's
             more
             to
             be
             considered
             ,
             than
             that
             four
             foot
             of
             VVater
             ,
             which
             in
             it self
             is
             but
             of
             small
             burden
             ,
             therefore
             to
             this
             we
             must
             add
             the
             weight
             of
             the
             Air
             between
             O
             and
             S
             ,
             within
             the
             Pipe
             (
             remember
             that
             the
             orifice
             S
             is
             stopped
             with
             the
             pulp
             of
             the
             Finger
             )
             which
             in
             effect
             will
             be
             as
             heavy
             as
             31
             foot
             of
             VVater
             .
             Put
             the
             case
             then
             ,
             F
             ,
             to
             be
             one
             foot
             below
             the
             first
             surface
             H
             I
             K
             ,
             and
             the
             VVater
             O
             I
             to
             be
             three
             foot
             ,
             then
             ought
             the
             Air
             O
             S
             ,
             to
             have
             the
             weight
             of
             31
             foot
             ,
             because
             the
             surface
             E
             F
             G
             is
             able
             to
             support
             a
             Pillar
             of
             35
             foot
             .
             This
             I
             prove
             ,
             because
             the
             part
             E
             ,
             
               de
               facto
            
             ,
             sustains
             35
             foot
             ,
             because
             the
             Air
             above
             is
             equivalent
             to
             34
             foot
             of
             it
             ,
             and
             there
             is
             a
             foot
             of
             VVater
             between
             it
             and
             the
             top
             ,
             namely
             between
             E
             and
             H.
             The
             third
             question
             is
             ,
             how
             it
             comes
             to
             pass
             ,
             that
             the
             Water
             still
             remains
             in
             the
             Pipe
             ,
             after
             the
             orifice
             M
             is
             brought
             above
             the
             surface
             of
             the
             Water
             ;
             for
             there
             is
             here
             no
             stagnant
             Water
             guarding
             it
             ,
             as
             guards
             the
             orifice
             F.
             I
             answer
             ,
             that
             the
             base
             M
             ,
             of
             this
             Pillar
             of
             Water
             P
             M
             ,
             as
             really
             rests
             upon
             the
             horizontal
             surface
             of
             this
             Air
             L
             M
             N
             ,
             as
             a
             Cylinder
             of
             Brass
             or
             Timber
             rests
             upon
             a
             plain
             Marble
             Table
             ,
             and
             after
             the
             same
             manner
             .
             Remember
             that
             the
             orifice
             T
             is
             stopped
             all
             this
             time
             ,
             with
             the
             pulp
             of
             the
             Finger
             .
             If
             it
             be
             said
             ,
             that
             the
             part
             M
             ,
             is
             more
             burdened
             then
             the
             part
             N
             ,
             seing
             it
             sustains
             four
             foot
             of
             Water
             ,
             which
             the
             part
             N
             supports
             not
             ,
             and
             the
             Air
             P
             T
             within
             the
             Pipe
             also
             ,
             which
             is
             of
             as
             much
             Bensil
             and
             Pressure
             ,
             as
             the
             Air
             N
             Y
             is
             of
             .
             For
             clearing
             of
             this
             difficulty
             ,
             consider
             ,
             that
             the
             Pillar
             P
             M
             is
             shorter
             now
             than
             before
             ;
             for
             the
             orifice
             M
             coming
             up
             from
             D
             ,
             some
             inches
             of
             Water
             falls
             out
             ,
             as
             will
             be
             found
             by
             experience
             .
             Suppose
             
             then
             ,
             that
             of
             four
             foot
             ,
             six
             inches
             fall
             out
             ;
             if
             this
             be
             ,
             then
             the
             inclosed
             Air
             between
             P
             and
             T
             ,
             must
             be
             〈◊〉
             inches
             longer
             ,
             if
             this
             be
             ,
             then
             of
             necessity
             the
             Bensil
             of
             it
             must
             be
             proportionably
             remitted
             and
             slackened
             :
             whence
             follows
             by
             Metaphysical
             necessity
             ,
             that
             it
             cannot
             burden
             the
             Water
             P
             M
             ,
             with
             as
             much
             weight
             as
             it
             had
             ,
             and
             consequently
             the
             surface
             of
             Air
             cannot
             be
             so
             much
             burdened
             .
             It
             must
             then
             be
             no
             more
             bu●dened
             with
             them
             both
             together
             ,
             than
             it
             is
             with
             the
             single
             Pillar
             of
             Air
             Y
             N.
             If
             then
             the
             Water
             P
             M
             ,
             be
             three
             foot
             and
             an
             half
             ,
             the
             weight
             of
             the
             enclosed
             Air
             T
             P
             ,
             must
             be
             exactly
             the
             weight
             of
             thirty
             foot
             of
             Water
             and
             an
             half
             .
          
           
             From
             this
             experiment
             ,
             we
             see
             first
             the
             Pressure
             of
             the
             Air
             ,
             for
             by
             it
             the
             Water
             O
             I
             is
             suspended
             ,
             and
             by
             the
             same
             pressure
             is
             the
             Water
             P
             M
             suspended
             .
             We
             see
             secondly
             ,
             that
             in
             Air
             ,
             there
             is
             a
             power
             of
             dilating
             it self
             ,
             and
             that
             this
             dilatation
             never
             happens
             ,
             without
             a
             relaxation
             of
             the
             Bensil
             .
             We
             see
             thirdly
             ,
             that
             one
             Fluid
             cannot
             sustain
             another
             ,
             unless
             the
             Potentia
             of
             the
             one
             ,
             be
             equal
             to
             the
             Pondus
             of
             the
             other
             ,
             as
             is
             clear
             from
             the
             Aërial
             surface
             ,
             that
             cannot
             sustain
             the
             whole
             four
             foot
             of
             Water
             ,
             but
             suffers
             six
             inches
             of
             it
             to
             fall
             out
             ,
             that
             the
             Pondus
             of
             the
             rest
             ,
             and
             the
             Air
             above
             it
             ,
             may
             become
             equal
             to
             its
             own
             Potentia
             .
             We
             see
             fourthly
             ,
             that
             Fluid
             Bodies
             have
             not
             only
             a
             power
             of
             pressing
             downward
             ,
             but
             of
             pressing
             upward
             likewise
             :
             as
             is
             clear
             from
             the
             Water
             O
             I
             ,
             that
             's
             suspended
             by
             the
             Air
             pressing
             down
             the
             surface
             of
             Water
             H
             I
             K.
             It
             presseth
             upward
             also
             ,
             while
             it
             supports
             the
             Water
             P
             M.
             This
             Experiment
             also
             answers
             a
             case
             ,
             namely
             ,
             whether
             or
             not
             ,
             it
             is
             alwayes
             needful
             to
             guard
             the
             orifice
             of
             the
             Tub
             of
             the
             Baroscope
             with
             stagnant
             Quick-silver
             ?
             I
             say
             then
             ,
             it
             is
             not
             alwayes
             needful
             ,
             provided
             the
             orifice
             be
             of
             a
             narrow
             
             diameter
             ;
             for
             experience
             tells
             ,
             that
             while
             it
             is
             such
             ,
             the
             Mercury
             will
             subside
             ,
             and
             halt
             at
             29
             inches
             above
             the
             orifice
             ,
             though
             no
             stagnant
             Mercury
             be
             to
             guard
             .
             In
             making
             this
             trial
             ,
             the
             orifice
             must
             be
             no
             wider
             ,
             than
             may
             admit
             the
             point
             of
             a
             needle
             .
             Or
             suppose
             it
             to
             have
             the
             wideness
             of
             a
             Tobacco-pipe
             ,
             yet
             will
             the
             Mercury
             be
             suspended
             ,
             though
             the
             end
             be
             not
             drowned
             among
             stagnant
             Quicksilver
             ,
             even
             as
             the
             Water
             P
             M
             ,
             is
             kept
             up
             without
             stagnant
             Water
             about
             it
             .
             For
             trial
             of
             this
             ,
             you
             must
             first
             let
             the
             end
             of
             the
             Pipe
             ,
             be
             put
             down
             among
             stagnant
             Mercury
             ,
             and
             after
             the
             Cylinder
             is
             fallen
             down
             to
             its
             own
             proper
             altitude
             ,
             lift
             up
             the
             Pipe
             slowly
             ,
             till
             the
             orifice
             come
             above
             the
             surface
             ,
             and
             you
             will
             find
             ,
             provided
             you
             do
             not
             shake
             the
             Pipe
             ,
             the
             Cylinder
             to
             be
             suspended
             after
             the
             same
             manner
             ,
             immediatly
             by
             the
             Air
             ,
             as
             the
             Water
             P
             M
             is
             .
          
        
         
           
             EXPERIMENT
             VII
             .
             Figure
             10
             ,
             11.
             
          
           
             TAke
             a
             Vessel
             of
             any
             quantity
             ,
             such
             as
             A
             B
             C
             D
             E
             ,
             and
             fill
             it
             with
             VVater
             .
             And
             a
             Glass-pipe
             ,
             such
             as
             G
             F
             D
             ,
             of
             15
             or
             20
             inches
             long
             ,
             of
             any
             wideness
             ,
             closs
             above
             ,
             and
             open
             below
             .
             Before
             you
             drown
             the
             open
             end
             among
             the
             VVater
             ,
             hold
             the
             Glass
             before
             the
             fire
             ,
             till
             it
             be
             pretty
             hot
             ,
             and
             having
             put
             it
             down
             ,
             you
             will
             see
             the
             VVater
             begin
             to
             creep
             up
             till
             it
             come
             to
             F
             ,
             where
             it
             halts
             .
             The
             question
             now
             is
             ,
             what
             's
             the
             reason
             ,
             why
             the
             VVater
             creeps
             up
             after
             this
             manner
             ,
             10
             or
             12
             inches
             above
             the
             surface
             A
             B
             ?
             I
             answer
             ,
             the
             heat
             having
             rarified
             the
             Air
             within
             ,
             and
             by
             this
             means
             ,
             having
             expelled
             much
             of
             it
             ,
             and
             the
             Air
             now
             contracting
             it self
             again
             with
             cold
             ,
             the
             
             VVater
             ascends
             ,
             being
             prest
             up
             with
             the
             weight
             of
             the
             incumbing
             Air
             ,
             resting
             upon
             the
             surface
             of
             Water
             A
             B.
             There
             is
             here
             surely
             an
             inequality
             between
             a
             Pondus
             and
             a
             Potentia
             ,
             that
             must
             be
             the
             cause
             of
             this
             motion
             .
             I
             judge
             then
             the
             inequality
             to
             consist
             between
             the
             weight
             of
             the
             Air
             within
             the
             Pipe
             ,
             and
             the
             surface
             of
             Water
             C
             D
             E.
             To
             explicate
             this
             ,
             I
             must
             suppose
             the
             Pipe
             to
             be
             thrust
             down
             cold
             ;
             in
             this
             case
             ,
             little
             or
             no
             Water
             can
             enter
             the
             orifice
             D.
             And
             the
             reason
             is
             ,
             because
             the
             Pondus
             of
             the
             Air
             within
             the
             Glass
             ,
             is
             equal
             to
             the
             Potentia
             of
             the
             surface
             C
             D
             E.
             But
             when
             the
             Pipe
             is
             thrust
             down
             hot
             ,
             much
             of
             the
             Air
             having
             been
             expelled
             by
             the
             heat
             ,
             and
             now
             beginning
             to
             be
             contracted
             by
             cold
             ,
             the
             Pondus
             of
             the
             Air
             becomes
             unequal
             to
             the
             Potentia
             of
             the
             surface
             ,
             and
             therefore
             this
             ,
             being
             the
             stronger
             party
             ,
             drives
             up
             the
             Air
             within
             the
             Glass
             ,
             till
             by
             this
             ascent
             ,
             the
             Pondus
             of
             the
             Air
             G
             F
             ,
             and
             the
             Pondus
             of
             the
             Water
             F
             D
             together
             ,
             become
             equal
             to
             the
             Potentia
             of
             the
             surface
             C
             D
             E
             ,
             that
             sustains
             them
             .
             For
             a
             second
             trial
             ;
             bring
             a
             hot
             coal
             near
             to
             the
             side
             of
             the
             Glass
             ,
             between
             G
             and
             F
             ,
             and
             you
             will
             find
             the
             Water
             to
             creep
             down
             from
             F
             toward
             the
             surface
             A
             B
             ;
             and
             if
             it
             continue
             any
             space
             ,
             it
             will
             drive
             down
             the
             whole
             Water
             ,
             and
             thrust
             it
             out
             at
             D.
             To
             explicate
             this
             ,
             I
             must
             suppose
             that
             heat
             ,
             by
             rarifying
             the
             Air
             within
             the
             Glass
             ,
             intends
             and
             increaseth
             the
             Bensil
             of
             it
             ,
             and
             the
             Bensil
             being
             now
             made
             stronger
             ,
             there
             must
             arise
             an
             inequality
             between
             the
             Pondus
             of
             the
             said
             Air
             ,
             and
             the
             Potentia
             of
             the
             surface
             C
             D
             E
             ;
             the
             Air
             then
             ,
             being
             the
             stronger
             party
             ,
             causeth
             the
             surface
             to
             yeeld
             .
          
           
             By
             comparing
             this
             Experiment
             with
             the
             former
             ,
             we
             see
             a
             great
             difference
             between
             the
             dilatation
             of
             Air
             ,
             of
             its
             own
             accord
             ,
             and
             by
             constraint
             .
             For
             while
             it
             is
             willingly
             expanded
             ,
             
             the
             Bensil
             begins
             to
             grow
             slack
             ,
             and
             remiss
             ,
             and
             loseth
             by
             degrees
             of
             its
             strength
             ;
             even
             as
             the
             Spring
             of
             a
             Watch
             by
             the
             motion
             of
             the
             Wheels
             ,
             becomes
             remiss
             .
             But
             when
             the
             dilatation
             is
             made
             by
             heat
             ,
             and
             the
             Air
             compelled
             to
             expand
             and
             open
             it self
             ,
             the
             Bensil
             becomes
             the
             stronger
             ,
             and
             the
             Pressure
             the
             greater
             .
             Notwithstanding
             ,
             though
             the
             Bensil
             of
             this
             inclosed
             Air
             G
             F
             ,
             may
             be
             made
             stronger
             by
             heat
             ,
             to
             the
             expulsion
             of
             the
             Water
             F
             D
             ,
             yet
             if
             this
             rarefact
             on
             continue
             any
             time
             ,
             the
             Bensil
             becomes
             dull
             and
             slack
             .
             And
             the
             reason
             is
             ,
             because
             Air
             cannot
             be
             expanded
             and
             opened
             to
             any
             quantity
             ;
             an
             inch
             cannot
             be
             dilated
             and
             opened
             to
             an
             hundred
             ,
             or
             to
             a
             thousand
             :
             neither
             can
             the
             Bensil
             of
             it
             be
             intended
             ,
             and
             increase
             to
             any
             degree
             ,
             
               v.
               g.
            
             from
             one
             to
             20
             ,
             30
             ,
             or
             100.
             
             And
             therefore
             ,
             as
             the
             expansion
             grows
             ,
             the
             Bensil
             must
             at
             length
             slacken
             .
             But
             if
             so
             be
             the
             Air
             were
             inclosed
             ,
             as
             in
             a
             bladder
             knit
             about
             the
             neck
             with
             a
             string
             ,
             then
             the
             more
             heat
             ,
             the
             more
             Bensil
             :
             for
             in
             this
             case
             there
             is
             a
             growth
             of
             Pressure
             ,
             without
             dilatation
             .
             And
             sometimes
             the
             Bensil
             may
             be
             so
             intended
             with
             the
             heat
             ,
             that
             the
             sides
             of
             the
             bladder
             will
             burst
             asunder
             .
          
           
             From
             this
             Experiment
             we
             see
             first
             a
             confirmation
             of
             the
             21
             Theorem
             ,
             namely
             ,
             that
             there
             may
             be
             as
             much
             Bensil
             and
             Pressure
             ,
             in
             the
             smallest
             quantity
             of
             a
             Fluid
             ,
             as
             in
             the
             greatest
             ;
             as
             is
             clear
             from
             the
             Bensil
             of
             the
             Air
             G
             F
             ,
             which
             in
             effect
             counterpoiseth
             the
             weight
             of
             the
             whole
             Atmosphere
             ,
             resting
             upon
             the
             surface
             of
             Water
             A
             B.
             We
             see
             secondly
             ,
             that
             when
             the
             pondus
             ,
             and
             the
             potentia
             of
             two
             Fluids
             ,
             are
             in
             equilibrio
             ,
             or
             of
             equal
             strength
             ,
             a
             very
             small
             addition
             to
             either
             of
             them
             ,
             will
             cast
             the
             ballance
             .
             For
             if
             a
             man
             should
             but
             breath
             softly
             upon
             the
             side
             of
             the
             Glass
             between
             G
             and
             F
             ,
             or
             lay
             his
             warm
             hand
             to
             it
             ,
             the
             said
             Air
             will
             presently
             dilate
             it self
             ,
             and
             by
             becoming
             thus
             stronger
             ,
             
             thrust
             down
             the
             Water
             ,
             and
             so
             overcome
             the
             potentia
             of
             the
             surface
             .
             We
             see
             thirdly
             a
             confirmation
             of
             the
             sixth
             Theorem
             ,
             namely
             ,
             that
             the
             Pressure
             of
             Fluids
             is
             on
             every
             side
             ;
             as
             is
             clear
             from
             the
             inclosed
             Air
             G
             F
             ,
             that
             not
             only
             presseth
             down
             the
             Water
             F
             D
             ,
             but
             with
             as
             great
             force
             presseth
             up
             the
             top
             of
             the
             Glass
             within
             ,
             and
             presseth
             upon
             all
             the
             sides
             of
             it
             within
             ,
             with
             the
             same
             force
             .
             This
             Experiment
             also
             ,
             leads
             us
             to
             the
             knowledge
             of
             two
             things
             :
             First
             ,
             of
             the
             reason
             ,
             why
             with
             cold
             the
             Water
             ascends
             in
             the
             common
             Weather-glasses
             ;
             and
             why
             in
             hot
             weather
             the
             Water
             descends
             .
             Secondly
             ,
             from
             this
             Experiment
             we
             may
             learn
             to
             know
             ,
             when
             the
             Air
             is
             under
             a
             greater
             Pressure
             ,
             and
             when
             under
             a
             lesser
             :
             because
             when
             the
             Air
             becomes
             heavier
             ,
             as
             in
             fair
             weather
             ,
             the
             Water
             creeps
             up
             in
             some
             measure
             ,
             it
             may
             be
             two
             or
             three
             inches
             ;
             when
             there
             is
             no
             alteration
             as
             to
             heat
             and
             cold
             :
             and
             in
             foul
             weather
             ,
             or
             in
             great
             winds
             ,
             when
             the
             Air
             is
             really
             lighter
             ,
             the
             said
             Water
             creeps
             down
             as
             much
             .
             If
             it
             be
             asked
             ,
             how
             shall
             I
             know
             ,
             whether
             it
             be
             the
             cold
             of
             the
             Air
             ,
             or
             heaviness
             of
             the
             Air
             ,
             that
             causeth
             the
             Water
             to
             ascend
             ;
             and
             whether
             it
             be
             the
             heat
             of
             the
             Air
             ,
             or
             the
             lightness
             of
             the
             Air
             ,
             that
             causeth
             the
             Water
             to
             descend
             ?
             I
             have
             proposed
             this
             question
             of
             purpose
             ,
             to
             let
             you
             see
             a
             mistake
             .
             Many
             believe
             ,
             that
             the
             ascent
             and
             descent
             of
             Water
             in
             common
             Weather-glasses
             ,
             is
             allanerly
             from
             the
             heat
             and
             coldness
             of
             the
             Air
             ;
             and
             therefore
             they
             conclude
             a
             cold
             day
             to
             be
             ,
             because
             the
             Water
             is
             far
             up
             :
             whereas
             the
             Water
             hath
             ascended
             since
             the
             last
             night
             ,
             by
             reason
             of
             a
             greater
             weight
             in
             the
             Air
             ,
             which
             alwayes
             is
             ,
             when
             the
             weather
             is
             dry
             ,
             and
             calm
             ,
             though
             there
             hath
             been
             no
             alteration
             of
             heat
             to
             cold
             .
             If
             it
             be
             asked
             ,
             how
             come
             we
             to
             the
             knowledge
             of
             this
             ,
             that
             the
             pressure
             and
             weight
             of
             the
             Element
             of
             Air
             ,
             is
             sometimes
             
             less
             ,
             and
             sometimes
             more
             ?
             I
             answer
             ,
             this
             secret
             o
             Nature
             ,
             was
             never
             discovered
             ,
             till
             the
             invention
             of
             the
             
               Torricellian
               Experiment
            
             ,
             otherwise
             called
             the
             Baroscope
             .
             For
             after
             the
             falling
             down
             of
             the
             Quick-silver
             to
             29
             inches
             :
             if
             you
             suffer
             it
             to
             stand
             thus
             in
             your
             Parlour
             or
             Chamber
             ,
             according
             as
             the
             Pressure
             ,
             and
             weight
             of
             the
             Element
             of
             Air
             ,
             becomes
             more
             or
             less
             ,
             so
             will
             the
             Altitude
             of
             the
             Mercury
             become
             less
             or
             more
             ,
             and
             vary
             sometimes
             above
             29
             inches
             ,
             and
             sometimes
             below
             .
             This
             alteration
             is
             very
             sensible
             ,
             which
             is
             sometimes
             the
             tenth
             part
             of
             an
             inch
             ,
             sometimes
             the
             sixth
             ,
             and
             sometimes
             the
             third
             ,
             according
             as
             the
             weight
             of
             the
             Air
             is
             less
             or
             more
             .
             From
             December
             to
             February
             ,
             I
             found
             the
             alteration
             become
             less
             and
             more
             from
             30
             inches
             to
             28
             ,
             which
             will
             be
             three
             fingers
             breadth
             .
             The
             common
             Weather-glasses
             then
             are
             fallacious
             ,
             and
             deceitful
             ,
             unless
             they
             be
             so
             contrived
             ,
             that
             the
             Pressure
             of
             the
             Air
             cannot
             affect
             them
             ,
             which
             is
             easily
             done
             by
             sealing
             them
             Hermetically
             ,
             and
             in
             stead
             of
             common
             Water
             ,
             to
             put
             in
             
               Spiritus
               Vini
               rectificatissimus
            
             ,
             or
             the
             most
             excellent
             Spirit
             of
             Wine
             ,
             and
             strongest
             that
             can
             be
             made
             .
          
           
             It
             may
             be
             here
             inquired
             ,
             whether
             or
             not
             ,
             Mercury
             would
             ascend
             in
             this
             Glass
             ,
             as
             the
             Water
             does
             ?
             I
             answer
             it
             would
             ;
             because
             the
             ascent
             depends
             only
             upon
             the
             Pressure
             of
             the
             Air
             ,
             incumbing
             upon
             the
             stagnant
             Liquor
             in
             the
             Vessell
             ,
             that
             's
             able
             to
             drive
             up
             Mercury
             as
             well
             as
             Water
             .
             It
             may
             be
             inquired
             secondly
             ,
             how
             far
             Mercury
             will
             ascend
             ,
             and
             how
             far
             Water
             will
             creep
             up
             ?
             I
             answer
             ,
             Mercury
             can
             ascend
             no
             higher
             in
             a
             Tub
             ,
             than
             29
             inches
             ;
             and
             Water
             no
             higher
             ,
             than
             34
             foot
             ;
             and
             this
             onely
             happens
             ,
             when
             there
             is
             no
             Air
             above
             the
             tops
             of
             the
             Cylinders
             to
             hinder
             their
             ascents
             .
             But
             when
             there
             is
             Air
             ,
             as
             G
             F
             above
             the
             liquor
             ,
             it
             can
             go
             no
             higher
             ,
             than
             the
             point
             to
             which
             the
             cold
             is
             
             able
             to
             contract
             the
             inclosed
             Air
             ,
             which
             is
             in
             this
             Glass
             ,
             the
             point
             F.
             It
             may
             be
             inquired
             thirdly
             ,
             which
             is
             the
             greater
             difficulty
             ,
             whether
             or
             not
             Mercury
             ,
             will
             rise
             as
             easily
             in
             a
             Tub
             as
             Water
             ;
             for
             seeing
             ,
             it
             s
             14
             times
             heavier
             ,
             it
             seemes
             the
             Air
             should
             have
             greater
             difficulty
             to
             press
             it
             up
             ,
             than
             to
             press
             up
             Water
             ?
             I
             answer
             ,
             't
             is
             greater
             difficulty
             for
             the
             Air
             to
             press
             up
             20
             inches
             of
             Mercury
             ,
             than
             to
             press
             up
             20
             inches
             of
             Water
             ;
             yet
             it
             s
             no
             greater
             difficulty
             ,
             for
             the
             Air
             to
             press
             up
             20
             inches
             of
             Mercury
             ,
             than
             to
             press
             up
             23
             foot
             of
             Water
             ,
             because
             the
             burden
             and
             weight
             is
             the
             same
             .
             It
             may
             be
             inquired
             fourthly
             ,
             whether
             or
             not
             ,
             it
             be
             as
             easie
             for
             the
             Air
             ,
             to
             press
             up
             a
             thick
             and
             gross
             Cylinder
             of
             Water
             ,
             as
             to
             press
             up
             a
             thin
             and
             slender
             one
             ?
             For
             example
             ,
             whether
             is
             it
             as
             easie
             for
             the
             Air
             to
             press
             up
             a
             Cylinder
             of
             Water
             10
             inches
             in
             Diameter
             ,
             and
             10
             foot
             high
             ,
             as
             it
             is
             to
             press
             up
             one
             ,
             two
             inches
             in
             diameter
             ,
             and
             10
             foot
             high
             ?
             I
             answer
             ,
             there
             is
             no
             more
             difficulty
             in
             the
             one
             ,
             than
             in
             the
             other
             :
             and
             the
             reason
             is
             ,
             because
             Fluid
             bodies
             do
             not
             counterpoise
             one
             another
             according
             to
             their
             thickness
             ,
             but
             only
             according
             to
             their
             altitude
             ,
             according
             to
             the
             fourth
             Theorem
             .
             Therefore
             seeing
             the
             slender
             Cylinder
             is
             as
             high
             as
             the
             grosser
             ,
             it
             must
             be
             no
             more
             difficult
             to
             the
             Air
             ,
             to
             press
             up
             the
             one
             then
             the
             other
             .
          
           
             There
             is
             one
             difficulty
             yet
             remaining
             ,
             which
             is
             truely
             the
             greatest
             of
             all
             ;
             namely
             what
             's
             the
             reason
             ,
             why
             its
             more
             difficult
             to
             the
             Air
             ,
             to
             press
             up
             20
             inches
             of
             Mercury
             ,
             than
             to
             press
             up
             20
             inches
             of
             Water
             :
             or
             more
             difficult
             to
             the
             Air
             ,
             to
             press
             up
             20
             inches
             of
             Mercury
             ,
             than
             to
             press
             up
             10
             ?
             I
             answer
             ,
             this
             comes
             to
             pass
             ,
             because
             the
             Air
             is
             more
             burthened
             with
             20
             inches
             of
             Mercury
             ,
             than
             with
             10.
             
             Now
             ,
             if
             this
             be
             ,
             then
             surely
             it
             must
             be
             more
             hard
             to
             the
             Air
             ,
             to
             do
             the
             one
             ,
             than
             to
             do
             the
             other
             :
             even
             as
             it
             is
             more
             
             hard
             ;
             for
             a
             man
             ,
             to
             lift
             up
             from
             the
             ground
             ,
             20
             pound
             of
             iron
             ,
             than
             to
             lift
             up
             10
             or
             15.
             
             The
             case
             may
             be
             better
             illustrated
             after
             this
             manner
             .
             Suppose
             a
             man
             standing
             on
             the
             ground
             ,
             with
             a
             rope
             in
             his
             hand
             ,
             coming
             down
             from
             a
             Pulley
             above
             ,
             drawing
             up
             a
             weight
             to
             the
             top
             of
             the
             house
             :
             put
             the
             case
             likewise
             ,
             the
             weight
             be
             a
             stone
             of
             20
             pound
             ,
             and
             the
             weight
             of
             it
             ,
             to
             increase
             successively
             ,
             as
             it
             is
             pulled
             up
             .
             Now
             its
             easie
             for
             the
             man
             to
             pull
             up
             the
             stone
             the
             first
             fathom
             ;
             because
             it
             is
             but
             20
             pound
             weight
             :
             but
             the
             stone
             becoming
             40
             pound
             in
             the
             second
             fathom
             ,
             and
             60
             in
             the
             third
             ,
             and
             80
             in
             the
             fourth
             and
             so
             forth
             ,
             untill
             it
             become
             1000
             ,
             he
             will
             find
             the
             greater
             difficulty
             ,
             the
             longer
             he
             pulls
             .
             'T
             is
             just
             so
             with
             Air
             ,
             or
             Water
             ,
             raising
             Mercury
             in
             a
             Tub
             ;
             for
             as
             the
             Cylinder
             of
             the
             Mercury
             grows
             higher
             by
             rising
             ,
             so
             it
             becomes
             heavier
             ,
             and
             consequently
             the
             imaginary
             surface
             ,
             upon
             which
             the
             Base
             of
             the
             Pillar
             rests
             ,
             is
             more
             and
             more
             burdened
             ,
             and
             so
             becomes
             less
             and
             less
             able
             to
             press
             it
             up
             .
             This
             leads
             us
             to
             a
             clear
             discovery
             of
             the
             reason
             ,
             why
             't
             is
             more
             difficult
             by
             suction
             ,
             to
             pull
             up
             Mercury
             in
             a
             Pipe
             ,
             than
             to
             pull
             up
             Water
             ;
             and
             more
             hard
             to
             suck
             up
             ten
             foot
             of
             Water
             ,
             then
             to
             suck
             up
             five
             .
             For
             trial
             of
             this
             ,
             which
             is
             soon
             done
             ,
             take
             a
             slender
             Glass-pipe
             30
             or
             40
             inches
             long
             ,
             open
             at
             both
             ends
             ,
             and
             drown
             the
             one
             end
             among
             Quick-silver
             ,
             and
             put
             your
             mouth
             to
             the
             other
             ,
             and
             having
             sucked
             ,
             you
             will
             find
             greater
             difficulty
             to
             pull
             up
             thorow
             the
             Pipe
             15
             inches
             of
             Mercury
             ,
             than
             to
             pull
             up
             10
             ,
             or
             8
             ;
             and
             far
             greater
             difficulty
             to
             suck
             up
             20
             ▪
             than
             to
             pull
             up
             15.
             
             It
             may
             be
             objected
             ,
             that
             if
             a
             man
             had
             strength
             sufficient
             in
             his
             Lungs
             ,
             to
             suck
             out
             the
             whole
             Air
             of
             the
             Pipe
             ,
             thirty
             inches
             of
             Mercury
             would
             come
             as
             easily
             up
             ,
             as
             three
             ,
             which
             seemes
             to
             prove
             ,
             that
             the
             difficulty
             of
             the
             Mercurie's
             up-coming
             ,
             depends
             not
             upon
             the
             weakness
             of
             
             the
             Air
             ,
             but
             upon
             the
             weakness
             of
             the
             Lungs
             ,
             and
             want
             of
             strength
             to
             suck
             .
             I
             answer
             ,
             though
             a
             man
             were
             able
             to
             suck
             out
             the
             whole
             Air
             of
             the
             Pipe
             ,
             yet
             30
             inches
             ,
             will
             never
             ascend
             so
             easily
             ,
             as
             ten
             ,
             nor
             ten
             so
             easily
             as
             three
             ,
             and
             that
             for
             the
             reasons
             already
             given
             .
             But
             why
             is
             it
             then
             ,
             (
             say
             you
             )
             that
             the
             stronger
             the
             suction
             be
             ,
             the
             higher
             the
             Mercury
             ascends
             in
             the
             Pipe
             ?
             I
             answer
             ,
             the
             suction
             serves
             for
             no
             use
             ,
             but
             to
             remove
             the
             impediment
             ,
             that
             hinders
             the
             Mercury
             from
             coming
             up
             ,
             which
             is
             nothing
             else
             ,
             but
             the
             Air
             within
             the
             Pipe.
             Now
             ,
             the
             more
             of
             this
             Air
             that
             's
             taken
             away
             by
             suction
             ,
             (
             the
             stronger
             the
             suction
             is
             ,
             the
             more
             Air
             is
             taken
             away
             )
             the
             ●arder
             up
             comes
             the
             Mercury
             .
             But
             why
             ought
             there
             to
             be
             difficulty
             in
             the
             suction
             of
             Mercury
             ,
             to
             the
             altitude
             of
             15
             or
             20
             inches
             ,
             more
             than
             in
             the
             suction
             of
             Water
             to
             that
             altitude
             ?
             I
             answer
             ,
             when
             I
             suck
             Water
             up
             thorow
             a
             Pipe
             ,
             the
             suction
             of
             the
             Air
             above
             it
             ,
             is
             easie
             ;
             because
             the
             ascending
             Water
             helpes
             much
             to
             drive
             it
             up
             to
             the
             mouth
             ,
             the
             outward
             Air
             driving
             up
             both
             ,
             But
             the
             suction
             is
             difficult
             in
             Mercury
             ,
             because
             the
             ascending
             liquor
             ,
             does
             not
             help
             so
             much
             ,
             to
             drive
             up
             the
             Air
             to
             the
             mouth
             ,
             as
             the
             Water
             does
             .
             And
             the
             reason
             is
             ,
             because
             the
             Air
             ,
             being
             more
             burdened
             with
             15
             inches
             of
             Mercury
             ,
             than
             with
             15
             inches
             of
             Water
             ,
             cannot
             so
             easily
             drive
             up
             the
             one
             as
             the
             o●her
             ,
             and
             so
             Mercury
             cannot
             so
             easily
             drive
             up
             the
             Air
             of
             the
             Pipe
             to
             the
             mouth
             ,
             as
             Water
             does
             .
             In
             a
             word
             ,
             according
             to
             the
             difference
             of
             specifick
             weight
             ,
             between
             Water
             and
             Mercury
             ,
             so
             is
             the
             difficulty
             of
             suction
             ;
             therefore
             ,
             because
             Mercury
             is
             14
             times
             heavier
             than
             Water
             ,
             there
             is
             14
             times
             more
             difficulty
             ,
             to
             pull
             up
             the
             one
             ,
             than
             the
             other
             .
             Note
             ,
             that
             suction
             is
             not
             taken
             here
             strictly
             ,
             as
             contradistinguished
             from
             pulsion
             ;
             but
             in
             a
             large
             sense
             ,
             as
             it
             may
             comprehend
             it
             .
          
           
           
             To
             proceed
             a
             little
             further
             ,
             let
             us
             suppose
             the
             Pillar
             of
             Mercury
             (
             see
             the
             11.
             
             Figure
             )
             G
             H
             ,
             that
             's
             raised
             by
             the
             surface
             of
             Air
             F
             G
             ,
             to
             be
             29
             inches
             ,
             and
             every
             inch
             to
             weigh
             one
             ounce
             .
             Secondly
             ,
             that
             the
             said
             surface
             has
             29
             degrees
             of
             power
             or
             force
             in
             it
             :
             for
             in
             all
             counterpoises
             the
             Pondus
             and
             the
             Potentia
             are
             equal
             ;
             therefore
             ,
             if
             the
             Mercury
             be
             29
             inches
             ,
             the
             Potentia
             of
             the
             surface
             must
             have
             29
             degrees
             of
             strength
             or
             force
             in
             it
             ,
             to
             counterballance
             the
             Pondus
             .
             These
             things
             being
             supposed
             ,
             which
             are
             evident
             ,
             let
             us
             imagine
             the
             surface
             of
             Air
             ,
             to
             raise
             the
             Mercury
             one
             inch
             above
             F
             G.
             In
             this
             case
             ,
             the
             surface
             is
             weaker
             than
             it
             was
             ;
             which
             I
             prove
             evidently
             ,
             because
             it
             is
             now
             but
             able
             to
             raise
             28
             of
             Mercury
             .
             Imagine
             next
             ,
             the
             said
             surface
             to
             have
             raised
             the
             Mercury
             two
             inches
             above
             F
             G
             ,
             then
             it
             follows
             ,
             that
             it
             must
             be
             yet
             weaker
             ,
             because
             it
             's
             now
             but
             able
             to
             raise
             27
             inches
             :
             for
             by
             supporting
             two
             ounce
             of
             the
             Pondus
             ,
             it
             loseth
             two
             degrees
             of
             it's
             own
             Potentia
             .
             In
             rai●ing
             three
             inches
             of
             Mercury
             ,
             it
             is
             three
             degrees
             weaker
             ;
             and
             in
             raising
             four
             ,
             it
             is
             four
             degrees
             weaker
             ,
             and
             so
             forth
             ;
             therefore
             ,
             having
             raised
             28
             inches
             ,
             there
             is
             but
             one
             degree
             of
             force
             remaining
             in
             the
             surface
             .
             And
             when
             it
             hath
             raised
             the
             whole
             ,
             namely
             29
             ,
             it
             is
             no
             more
             able
             ,
             and
             can
             no
             more
             press
             .
             For
             confirmation
             ,
             put
             the
             case
             that
             the
             surface
             of
             Air
             F
             G
             ,
             were
             as
             able
             ,
             and
             had
             as
             much
             Pressure
             in
             it
             ,
             after
             it
             hath
             raised
             29
             inches
             of
             Mercury
             ,
             as
             it
             is
             after
             the
             raising
             of
             10
             ;
             then
             it
             follows
             of
             necessity
             ,
             that
             after
             the
             raising
             of
             20
             ,
             it
             shall
             raise
             19
             moe
             ,
             which
             is
             impossible
             ,
             seing
             the
             greatest
             altitude
             is
             29.
             
             It
             follows
             of
             necessity
             ,
             (
             I
             say
             )
             because
             after
             the
             raising
             of
             10
             ,
             it
             is
             able
             to
             raise
             19
             moe
             :
             therefore
             if
             it
             be
             as
             able
             after
             20
             ,
             as
             after
             10
             ,
             it
             must
             raise
             19
             after
             20.
             
             Yea
             ,
             if
             it
             be
             as
             able
             after
             20
             as
             10
             ,
             it
             must
             be
             as
             
             able
             after
             29
             as
             10.
             
             If
             this
             be
             ,
             then
             it
             may
             raise
             other
             29
             ,
             and
             a
             third
             29
             ,
             and
             so
             
               in
               infinitum
            
             .
             Therefore
             ,
             I
             conclude
             ,
             that
             when
             two
             Fluid
             Bodies
             are
             in
             equilibrio
             one
             with
             another
             ;
             or
             when
             the
             pondus
             is
             equal
             to
             the
             potentia
             ,
             none
             of
             them
             doth
             actually
             press
             upon
             another
             ,
             at
             least
             the
             surface
             hath
             lost
             all
             its
             Power
             and
             Pressure
             ,
             which
             is
             also
             evident
             in
             the
             Pillar
             .
             For
             understanding
             this
             ,
             let
             us
             suppose
             A
             C
             B
             (
             Figure
             11.
             )
             to
             be
             a
             Pipe
             58
             inches
             long
             ,
             and
             full
             of
             Mercury
             ,
             and
             every
             inch
             of
             it
             to
             weigh
             one
             ounce
             .
             Now
             ,
             when
             the
             orifice
             D
             is
             opened
             ,
             there
             is
             here
             as
             great
             an
             inequality
             ,
             between
             the
             pondus
             and
             the
             potentia
             of
             the
             surface
             of
             Air
             E
             B
             ,
             on
             which
             it
             rests
             ,
             as
             was
             between
             the
             surface
             F
             G
             ,
             and
             the
             pondus
             of
             Mercury
             H
             G.
             For
             as
             F
             G
             had
             29
             degrees
             of
             power
             to
             raise
             G
             H
             ,
             so
             the
             Pillar
             A
             B
             has
             29
             ounce
             of
             weight
             ,
             to
             overcome
             the
             surface
             E
             B.
             And
             as
             the
             surface
             F
             G
             ,
             became
             one
             degree
             weaker
             ,
             by
             raising
             one
             inch
             of
             the
             Mercury
             H
             G
             ,
             and
             two
             degrees
             weaker
             ,
             by
             raising
             two
             inches
             ,
             and
             so
             forward
             ,
             till
             it
             lost
             all
             its
             Pressure
             ;
             so
             the
             Pillar
             ,
             by
             falling
             down
             one
             inch
             ,
             loseth
             one
             ounce
             of
             the
             weight
             ;
             by
             falling
             down
             two
             ,
             it
             loseth
             two
             ounce
             ,
             and
             so
             forward
             ,
             till
             by
             falling
             down
             from
             A
             to
             C
             ,
             it
             loseth
             all
             its
             Weight
             and
             Pressure
             .
          
           
             But
             here
             occurreth
             a
             difficulty
             ;
             for
             if
             the
             surface
             F
             G
             ,
             hath
             lost
             all
             its
             Pressure
             ,
             by
             raising
             the
             Mercury
             from
             G
             to
             H
             ;
             and
             if
             the
             Pillar
             C
             B
             ,
             hath
             lost
             all
             its
             Pressure
             ,
             by
             falling
             down
             from
             A
             to
             C
             ;
             it
             follows
             ,
             that
             when
             a
             Pillar
             of
             a
             Fluid
             ,
             and
             a
             surface
             of
             a
             Fluid
             are
             in
             equal
             termes
             ,
             or
             brought
             to
             an
             equipondium
             ,
             there
             is
             no
             Pressure
             in
             them
             at
             all
             .
             For
             answer
             ,
             consider
             first
             ,
             that
             in
             all
             counterpoises
             ,
             there
             are
             necessarily
             two
             things
             ,
             the
             movens
             and
             the
             motum
             ,
             the
             thing
             that
             moves
             ,
             and
             the
             thing
             that
             is
             moved
             .
             Secondly
             ,
             you
             must
             consider
             the
             motum
             ,
             to
             have
             a
             pondu●
             
             or
             weight
             in
             it
             ,
             and
             the
             movens
             to
             have
             a
             potentia
             ,
             or
             power
             ,
             wherewith
             it
             moves
             that
             weight
             .
             Thirdly
             ,
             that
             as
             the
             thing
             that
             moves
             ,
             hath
             a
             power
             or
             force
             in
             it self
             ,
             whereby
             it
             moves
             ,
             so
             the
             thing
             that
             is
             moved
             hath
             a
             power
             or
             force
             in
             it self
             ,
             whereby
             it
             resists
             the
             motion
             .
             Fourthly
             ,
             that
             sometimes
             the
             resistance
             of
             the
             thing
             moved
             ,
             may
             exceed
             the
             power
             of
             the
             movent
             ,
             as
             when
             a
             Quarrier
             with
             a
             Leaver
             ,
             endeavours
             to
             prize
             up
             a
             stone
             too
             heavy
             for
             him
             :
             or
             the
             power
             of
             the
             movent
             ,
             may
             exceed
             the
             resistance
             of
             the
             weight
             ;
             or
             both
             may
             be
             of
             equal
             power
             .
             Consider
             fifthly
             ,
             that
             as
             the
             pondus
             of
             the
             thing
             moved
             ,
             begins
             to
             grow
             more
             and
             more
             ,
             so
             the
             power
             of
             the
             movent
             decreaseth
             proportionably
             ;
             not
             absolutely
             ,
             as
             heat
             is
             extinguished
             in
             Water
             by
             the
             cold
             Air
             ,
             when
             it
             is
             removed
             from
             the
             Fire
             ,
             but
             respectively
             .
             For
             example
             ,
             when
             a
             man
             holds
             a
             ballance
             in
             his
             hand
             ,
             with
             six
             pound
             in
             the
             one
             scale
             ,
             and
             but
             one
             pound
             in
             the
             other
             ,
             if
             you
             add
             another
             pound
             ,
             the
             weight
             grows
             more
             ,
             and
             the
             power
             and
             force
             of
             the
             opposite
             scale
             grows
             less
             proportionably
             ;
             not
             absolutely
             ,
             for
             it
             still
             remains
             six
             pound
             ,
             but
             respectively
             :
             that
             's
             to
             say
             ,
             six
             pound
             is
             less
             in
             respect
             of
             four
             ,
             than
             in
             respect
             of
             five
             ;
             or
             the
             resistance
             of
             six
             pound
             is
             less
             ,
             two
             counterpoising
             it
             ,
             than
             being
             counterpoised
             by
             one
             .
             When
             a
             third
             is
             added
             ,
             the
             weight
             grows
             yet
             more
             ,
             and
             consequently
             the
             resistance
             of
             the
             opposite
             scale
             becomes
             yet
             less
             ,
             till
             by
             adding
             the
             sixth
             and
             last
             pound
             ,
             you
             augment
             and
             encrease
             the
             pondus
             to
             that
             same
             degree
             of
             strength
             ,
             that
             the
             resistance
             of
             the
             opposite
             scale
             is
             of
             .
             From
             these
             considerations
             ,
             I
             say
             ,
             the
             surface
             of
             Air
             F
             G
             ,
             hath
             not
             lost
             all
             its
             Pressure
             absolutely
             ,
             by
             raising
             the
             Mercury
             from
             G
             to
             H
             ,
             but
             only
             respectively
             ,
             because
             it
             still
             retains
             29
             degrees
             of
             force
             in
             it self
             .
             I
             say
             respectively
             ,
             because
             when
             the
             Mercury
             is
             
             raised
             ten
             inches
             ,
             the
             power
             of
             the
             Air
             which
             is
             of
             29
             degrees
             of
             force
             ,
             is
             less
             in
             respect
             of
             ten
             ounce
             ,
             then
             in
             respect
             of
             five
             ;
             or
             the
             power
             of
             29
             degrees
             of
             force
             is
             less
             ,
             being
             counterpoised
             by
             ten
             ounce
             ,
             than
             being
             counterpoised
             only
             by
             five
             .
             And
             when
             it
             is
             raised
             20
             ,
             it
             is
             yet
             less
             in
             this
             respect
             ,
             than
             in
             respect
             of
             ten
             .
             And
             when
             it
             has
             raised
             the
             Mercury
             to
             the
             greatest
             altitude
             H
             ,
             it
             may
             be
             said
             to
             have
             lost
             all
             its
             Pressure
             ,
             seing
             it
             is
             not
             able
             ,
             by
             vertue
             of
             a
             counterpoise
             ,
             to
             do
             any
             more
             .
             Even
             as
             six
             pound
             in
             this
             scale
             ,
             may
             be
             said
             to
             have
             lost
             all
             its
             resistance
             and
             weight
             ,
             by
             putting
             in
             the
             other
             scale
             ,
             first
             one
             pound
             ,
             next
             two
             pound
             ,
             and
             then
             three
             pound
             ,
             till
             the
             last
             be
             put
             in
             ,
             at
             which
             time
             it
             hath
             no
             more
             resistance
             .
             Though
             this
             be
             ,
             yet
             it
             still
             remains
             six
             pound
             .
             Even
             so
             ,
             the
             Air
             F
             G
             still
             remains
             of
             the
             same
             force
             and
             power
             ,
             while
             it
             suspends
             the
             Mercury
             G
             H
             ,
             that
             it
             was
             of
             before
             .
             Likewise
             ,
             the
             Pillar
             A
             B
             ,
             cannot
             be
             said
             to
             have
             lost
             all
             its
             pressure
             absolutely
             ,
             by
             falling
             down
             from
             A
             to
             C
             ,
             but
             only
             respectively
             ,
             because
             the
             said
             Pillar
             C
             B
             ,
             is
             still
             29
             ounce
             weight
             .
             I
             say
             respectively
             ,
             because
             in
             falling
             down
             ten
             inches
             ,
             or
             in
             losing
             ten
             ounce
             ,
             the
             weight
             that
             's
             now
             but
             48
             ,
             is
             less
             ,
             in
             respect
             of
             29
             ,
             than
             while
             it
             was
             58.
             
             It
             is
             yet
             less
             ,
             when
             it
             hath
             fallen
             down
             other
             ten
             ,
             because
             being
             now
             but
             38
             ,
             it
             must
             be
             yet
             less
             in
             respect
             of
             29
             ,
             than
             48.
             
             And
             when
             it
             hath
             fallen
             down
             to
             C
             29
             ,
             it
             may
             be
             said
             to
             have
             lost
             all
             its
             weight
             ,
             because
             it
             can
             do
             no
             more
             ,
             having
             respectively
             lost
             all
             its
             Pressure
             .
          
           
             From
             what
             is
             said
             ,
             we
             see
             a
             clear
             ground
             to
             distinguish
             in
             Fluids
             a
             pondus
             and
             a
             potentia
             .
             Secondly
             ,
             that
             the
             potentia
             may
             sometimes
             exceed
             the
             pondus
             ,
             and
             contrariwise
             the
             pondus
             may
             exceed
             the
             potentia
             .
             Thirdly
             ,
             that
             inequality
             of
             weight
             ,
             between
             the
             pondus
             and
             the
             potentia
             ,
             is
             
             the
             cause
             of
             motion
             of
             Fluids
             .
             Fourthly
             ,
             that
             the
             motion
             never
             ceaseth
             ,
             till
             the
             pondus
             and
             the
             potentia
             become
             of
             equal
             force
             .
             This
             conclusion
             is
             not
             so
             universal
             as
             the
             rest
             ,
             because
             the
             motion
             may
             sometimes
             cease
             ,
             before
             this
             be
             .
             For
             example
             ,
             when
             the
             Air
             is
             p●●●●ing
             Mercury
             up
             thorow
             a
             Tub
             shorter
             then
             29
             inches
             ,
             the
             motion
             ends
             before
             there
             be
             a
             perfect
             counterpoise
             ;
             for
             20
             or
             15
             inches
             of
             Mercury
             ,
             can
             never
             counterballance
             the
             force
             and
             power
             of
             the
             Air.
             In
             such
             a
             case
             then
             ,
             there
             is
             an
             unequal
             Pressure
             ,
             the
             Air
             pressing
             the
             Mercury
             more
             ,
             than
             the
             Mercury
             doth
             the
             Air.
             
          
        
         
           
             EXPERIMENT
             VIII
             .
             Figure
             12.
             
          
           
             TAke
             the
             Vessel
             A
             B
             C
             D
             ,
             and
             fill
             it
             with
             Water
             ,
             as
             high
             as
             H
             I.
             Take
             next
             a
             Cylinder
             of
             stone
             F
             G
             ,
             and
             drowning
             the
             half
             of
             it
             among
             the
             Water
             ,
             suspend
             it
             with
             a
             chord
             to
             the
             beam
             N
             O
             ,
             with
             a
             ring
             at
             E.
             Now
             in
             this
             case
             ,
             though
             the
             stone
             do
             not
             touch
             the
             bottom
             of
             the
             Vessel
             ,
             yet
             the
             Water
             becomes
             heavier
             ,
             than
             before
             .
             For
             discovering
             the
             true
             reason
             of
             this
             ,
             I
             suppose
             first
             ,
             the
             weight
             of
             the
             Water
             ,
             before
             the
             stone
             be
             drow●ed
             ,
             to
             be
             40
             pound
             .
             I
             suppose
             next
             ,
             that
             after
             the
             stone
             is
             drowned
             ,
             the
             said
             Water
             to
             weigh
             50
             pound
             .
             And
             lastly
             ,
             the
             stone
             to
             weigh
             60
             pound
             .
             I
             say
             then
             ,
             the
             Water
             must
             be
             10
             pound
             heavier
             than
             before
             ,
             because
             it
             supports
             10
             pound
             of
             the
             stone
             .
             'T
             is
             certain
             the
             beam
             is
             less
             burdened
             by
             10
             pound
             than
             before
             .
             If
             this
             be
             ,
             then
             surely
             the
             Water
             must
             sustain
             it
             .
             It
             were
             great
             temerity
             and
             rashness
             ,
             to
             averr
             that
             neither
             the
             Beam
             ,
             nor
             the
             Water
             sustains
             it
             ,
             
             which
             is
             really
             to
             say
             ,
             it
             is
             sustained
             by
             nothing
             .
             It
             cannot
             be
             said
             without
             ignorance
             ,
             that
             10
             pound
             of
             the
             stone
             is
             evanished
             ,
             and
             turned
             into
             a
             Chimera
             .
             If
             it
             be
             said
             ,
             how
             can
             such
             a
             Fluid
             Body
             as
             Water
             ,
             be
             able
             to
             support
             any
             part
             of
             the
             weight
             of
             the
             stone
             ,
             that
             is
             such
             a
             heavy
             Body
             ?
             I
             answer
             ,
             there
             is
             here
             no
             difficulty
             ,
             for
             if
             the
             imaginary
             surface
             K
             L
             ,
             upon
             which
             the
             10
             pound
             of
             the
             stone
             rests
             ,
             be
             able
             to
             sustain
             10
             pound
             of
             Water
             (
             I
             suppose
             the
             stone
             taken
             away
             ,
             and
             the
             place
             of
             it
             filled
             with
             Water
             )
             then
             surely
             it
             must
             also
             be
             able
             to
             sustain
             10
             pound
             of
             the
             heaviest
             metal
             ;
             seing
             ten
             pound
             of
             Lead
             ,
             or
             Gold
             ,
             or
             Stone
             ,
             is
             no
             heavier
             than
             10
             pound
             of
             VVater
             .
             If
             some
             say
             ,
             this
             rather
             seems
             to
             be
             the
             reason
             ,
             why
             the
             Water
             becomes
             heavier
             ,
             after
             the
             stone
             is
             drowned
             ,
             because
             it
             possesseth
             the
             place
             of
             as
             much
             Water
             ,
             as
             would
             weigh
             10
             pound
             ;
             not
             (
             as
             was
             said
             )
             because
             the
             VVater
             supports
             10
             pound
             of
             it
             .
             Therefore
             it
             may
             be
             judged
             ,
             and
             thought
             ,
             that
             if
             the
             space
             that
             the
             stone
             occupies
             ,
             were
             filled
             with
             Air
             ,
             or
             some
             light
             Body
             ,
             without
             sensible
             weight
             ,
             the
             VVater
             would
             become
             heavier
             than
             before
             .
             For
             example
             ,
             if
             instead
             of
             the
             stone
             ,
             there
             were
             placed
             a
             bladder
             full
             of
             wind
             ,
             within
             the
             VVater
             ,
             and
             tied
             to
             the
             bottom
             with
             a
             string
             ,
             that
             the
             surface
             might
             swell
             from
             H
             I
             to
             A
             B
             ,
             the
             VVater
             of
             the
             Vessel
             would
             become
             as
             much
             heavier
             than
             before
             ,
             as
             is
             the
             bulk
             of
             VVater
             ,
             equal
             to
             the
             quantity
             of
             the
             bladder
             .
             Therefore
             ,
             the
             VVater
             becomes
             heavier
             ,
             not
             because
             it
             supports
             any
             part
             of
             the
             stone
             ,
             but
             because
             the
             stone
             occupies
             as
             much
             room
             and
             space
             ,
             as
             would
             contain
             10
             pound
             of
             VVater
             :
             for
             by
             this
             means
             the
             drowned
             stone
             raiseth
             the
             VVater
             from
             H
             I
             to
             A
             B
             ;
             and
             so
             the
             Cylinders
             A
             C
             ,
             and
             B
             D
             ,
             being
             higher
             ,
             press
             with
             greater
             weight
             upon
             the
             bottom
             C
             D
             ,
             even
             with
             as
             much
             more
             weight
             ,
             
             as
             if
             the
             space
             that
             the
             stone
             occupies
             were
             filled
             with
             VVater
             .
          
           
             For
             answer
             to
             this
             ,
             we
             shall
             make
             this
             following
             Experiment
             .
             Take
             the
             Vessel
             M
             P
             V
             X
             ,
             and
             fill
             it
             with
             VVater
             to
             Q
             R.
             Next
             ,
             take
             a
             large
             bladder
             W
             Y
             full
             of
             wind
             ,
             and
             tying
             the
             neck
             with
             a
             threed
             ,
             thrust
             it
             below
             the
             Water
             ,
             and
             fasten
             it
             to
             the
             bottom
             ,
             with
             a
             string
             ,
             to
             the
             Ring
             Z.
             This
             done
             ,
             the
             Water
             swells
             ,
             and
             rises
             from
             Q
             R
             ,
             to
             M
             P.
             Now
             ,
             if
             it
             be
             true
             ,
             that
             the
             Water
             in
             the
             Vessel
             becomes
             heavier
             ,
             not
             because
             it
             supports
             10
             pound
             weight
             of
             the
             stone
             ,
             but
             because
             the
             stone
             occupies
             the
             room
             of
             10
             pound
             of
             Water
             ;
             then
             it
             ought
             to
             follow
             ,
             that
             after
             the
             bladder
             is
             tyed
             below
             the
             Water
             ,
             the
             said
             Water
             should
             become
             heavier
             ,
             than
             before
             ,
             even
             by
             three
             pound
             ;
             for
             I
             suppose
             a
             bulk
             of
             Water
             ,
             equal
             to
             the
             bulk
             of
             the
             bladder
             ,
             to
             weigh
             as
             much
             .
             And
             the
             reason
             is
             ,
             because
             (
             as
             you
             say
             )
             the
             quantity
             of
             the
             bladder
             W
             Y
             ,
             makes
             the
             water
             swell
             from
             Q
             R
             to
             M
             P
             ,
             by
             which
             means
             the
             Pillars
             of
             Water
             M
             V
             ,
             and
             P
             X
             becomes
             higher
             ,
             and
             so
             presseth
             with
             greater
             weight
             upon
             the
             bottom
             V
             X.
             For
             clearing
             this
             difficulty
             ,
             I
             say
             ,
             when
             a
             bladder
             is
             thus
             below
             the
             VVater
             ,
             tyed
             to
             the
             bottom
             ,
             the
             VVater
             becomes
             not
             three
             pound
             heavier
             :
             for
             when
             you
             place
             the
             Vessel
             with
             the
             VVater
             and
             bladder
             ,
             in
             the
             Scale
             of
             a
             Ballance
             ,
             the
             said
             VVater
             weighs
             no
             more
             ,
             than
             if
             it
             wanted
             the
             bladder
             :
             therefore
             the
             VVater
             becomes
             not
             heavier
             ,
             because
             the
             stone
             possesseth
             the
             room
             of
             10
             pound
             of
             Water
             ,
             but
             because
             the
             Water
             sustains
             10
             pound
             of
             the
             stone
             .
             Now
             the
             reason
             ,
             why
             the
             bladder
             makes
             not
             the
             water
             heavier
             ,
             though
             it
             raise
             it
             from
             Q
             R
             to
             M
             P
             ,
             is
             this
             ;
             because
             though
             verily
             there
             be
             a
             greater
             Pressure
             then
             before
             ,
             even
             upon
             the
             bottom
             of
             the
             Vessel
             ,
             yet
             because
             moe
             parts
             are
             not
             added
             ,
             
             the
             
               natural
               weight
            
             cannot
             be
             augmented
             ,
             which
             essentially
             depends
             upon
             the
             addition
             of
             these
             parts
             .
             If
             it
             be
             replyed
             ,
             the
             Experiment
             of
             the
             bladder
             is
             to
             no
             purpose
             ,
             because
             it
             being
             knit
             to
             the
             bottom
             ,
             pulls
             up
             the
             Vessel
             ,
             with
             as
             great
             force
             ,
             as
             the
             growth
             of
             the
             Pressure
             bears
             it
             down
             ,
             and
             so
             the
             Bladder
             cannot
             make
             the
             Water
             heavier
             .
             But
             ,
             if
             so
             be
             ,
             it
             were
             possible
             ,
             that
             the
             Bladder
             could
             remaine
             within
             the
             middle
             of
             the
             Water
             ,
             without
             being
             knit
             to
             the
             bottom
             ,
             and
             consequently
             without
             pulling
             up
             the
             Vessel
             ,
             then
             surely
             the
             Pillars
             of
             Water
             M
             V
             ,
             and
             P
             X
             ,
             being
             higher
             ,
             would
             press
             with
             greater
             weight
             upon
             the
             bottom
             ,
             and
             so
             make
             the
             Vessel
             ,
             and
             the
             Water
             weigh
             more
             in
             the
             ballance
             :
             for
             't
             is
             to
             be
             supposed
             ,
             that
             during
             all
             this
             time
             ,
             this
             Vessel
             with
             the
             Water
             ,
             is
             in
             one
             scale
             ,
             and
             a
             great
             weight
             of
             stone
             or
             lead
             ,
             in
             the
             other
             .
             So
             would
             the
             Water
             A
             B
             C
             D
             become
             heavier
             likewise
             ,
             provided
             the
             space
             and
             room
             ,
             that
             the
             stone
             fills
             among
             the
             Water
             ,
             remained
             intire
             ,
             after
             the
             stone
             is
             taken
             away
             :
             because
             that
             room
             and
             empty
             space
             remaining
             ,
             would
             keep
             the
             surface
             ,
             as
             high
             as
             A
             B
             ,
             by
             which
             means
             ,
             the
             Pillars
             A
             C
             and
             B
             D
             ,
             being
             higher
             ,
             would
             press
             with
             greater
             weight
             upon
             the
             bottom
             ,
             and
             cause
             the
             Water
             weigh
             more
             in
             the
             ballance
             .
             I
             answer
             ,
             though
             by
             some
             extraordinary
             power
             ,
             the
             bladder
             could
             remain
             below
             the
             water
             ,
             of
             its
             own
             accord
             ,
             as
             it
             were
             ,
             and
             though
             the
             space
             and
             room
             ,
             by
             that
             same
             power
             ,
             which
             is
             left
             by
             the
             stone
             ,
             were
             keeped
             empty
             ,
             yet
             shall
             they
             never
             be
             able
             to
             make
             the
             Water
             heavier
             .
             As
             to
             the
             reason
             ,
             that
             's
             brought
             ,
             I
             answer
             ,
             the
             rising
             and
             swelling
             of
             the
             Pillars
             ,
             will
             make
             indeed
             a
             greater
             Pressure
             upon
             the
             bottom
             of
             the
             Vessel
             ,
             but
             because
             this
             Pressure
             may
             be
             produced
             ,
             and
             generated
             without
             the
             addition
             of
             new
             parts
             ,
             therefore
             ,
             it
             can
             never
             make
             the
             Water
             heavier
             :
             for
             if
             this
             
             were
             true
             ,
             then
             it
             would
             follow
             ,
             that
             the
             more
             a
             body
             is
             comprest
             ,
             it
             should
             be
             the
             heavier
             ,
             which
             is
             contrary
             to
             sense
             ,
             and
             experience
             .
             This
             Pressure
             is
             like
             unto
             Bensil
             ,
             that
             cannot
             weigh
             in
             a
             ballance
             ,
             though
             the
             
               thing
               bended
            
             do
             weigh
             ;
             as
             a
             Bow
             that
             weighs
             so
             many
             pounds
             ,
             but
             the
             Bensil
             of
             it
             weighs
             nothing
             :
             Next
             ,
             will
             any
             man
             think
             ,
             that
             a
             Cub
             of
             Water
             six
             foot
             high
             ,
             and
             six
             foot
             thick
             ,
             will
             weigh
             more
             in
             a
             ballance
             ,
             then
             it
             did
             ,
             after
             it
             is
             turned
             into
             a
             long
             square
             Pillar
             216
             inches
             high
             ?
             I
             grant
             ,
             there
             is
             near
             60
             times
             a
             greater
             Pressure
             ,
             upon
             the
             bottom
             of
             the
             Vessel
             ,
             yet
             because
             this
             Pressure
             is
             generated
             ,
             without
             the
             addition
             of
             new
             parts
             ,
             it
             cannot
             make
             the
             Water
             heavier
             .
             Moreover
             ,
             it
             is
             mechanically
             possible
             to
             keep
             the
             VVater
             S
             T
             V
             X
             ,
             under
             that
             same
             degree
             of
             Pressure
             it
             hath
             ,
             though
             the
             rest
             above
             were
             taken
             away
             :
             if
             this
             be
             ,
             then
             it
             ought
             to
             be
             as
             heavy
             ,
             as
             the
             whole
             ,
             seing
             it
             still
             Presses
             the
             bottom
             ,
             with
             that
             same
             degree
             of
             Pressure
             ,
             it
             had
             from
             the
             whole
             :
             but
             what
             is
             more
             absurd
             ,
             than
             to
             say
             ,
             one
             part
             of
             VVater
             ,
             is
             as
             heavy
             ,
             as
             the
             whole
             ?
             
               e.
               g.
            
             a
             pint
             as
             heavy
             as
             a
             gallon
             .
             If
             it
             be
             said
             ,
             the
             Pressure
             ,
             and
             the
             weight
             ,
             are
             but
             one
             thing
             ,
             at
             least
             effectively
             ,
             which
             is
             sufficient
             to
             the
             purpose
             in
             hand
             ,
             as
             is
             clear
             from
             the
             Theorem
             23.
             
             I
             answer
             ,
             they
             are
             but
             one
             thing
             indeed
             ,
             in
             order
             to
             the
             
               Ballance
               of
               Nature
            
             ,
             but
             they
             are
             neither
             formally
             ,
             nor
             effectively
             the
             same
             thing
             in
             order
             to
             the
             Libra
             or
             
               Artificial
               Ballance
            
             ,
             whereof
             we
             are
             now
             treating
             .
             I
             shall
             conclude
             with
             this
             ;
             while
             the
             Vessel
             with
             the
             VVater
             ,
             is
             thus
             placed
             in
             the
             Scale
             of
             the
             Ballance
             ,
             and
             in
             equilibrio
             ,
             with
             the
             opposite
             Scale
             ,
             cut
             the
             string
             that
             tyes
             the
             bladder
             to
             the
             bottom
             ,
             and
             when
             it
             comes
             above
             ,
             you
             will
             find
             the
             VVater
             ,
             just
             of
             the
             same
             weight
             it
             was
             of
             :
             for
             though
             the
             surface
             M
             P
             ,
             by
             taking
             out
             the
             bladder
             ,
             settle
             down
             to
             Q
             R
             ,
             yet
             there
             's
             
             no
             alteration
             made
             in
             the
             weight
             .
             From
             this
             I
             gather
             ,
             that
             if
             the
             swelling
             of
             the
             VVater
             should
             make
             it
             heavier
             ,
             then
             the
             subsiding
             and
             falling
             down
             of
             it
             ,
             ought
             to
             make
             it
             lighter
             .
          
           
             From
             these
             Experiments
             we
             gather
             first
             ,
             that
             in
             VVater
             there
             is
             a
             Pressure
             ,
             because
             it
             sustains
             10
             pound
             of
             the
             stone
             F
             G.
             Secondly
             ,
             that
             whatever
             heavy
             body
             is
             weighed
             in
             Water
             ,
             it
             loseth
             just
             as
             much
             of
             its
             weight
             ,
             as
             the
             bulk
             of
             Water
             weighs
             ,
             it
             puts
             out
             of
             its
             place
             .
             This
             is
             evident
             ,
             because
             the
             stone
             is
             10
             pound
             lighter
             in
             VVater
             ,
             than
             in
             the
             Air
             ,
             because
             the
             VVater
             that
             would
             fill
             the
             room
             of
             the
             stone
             ,
             is
             just
             of
             that
             weight
             .
             VVe
             see
             thirdly
             ,
             that
             the
             Pressure
             of
             VVater
             ,
             and
             the
             
               natural
               weight
            
             of
             it
             ,
             are
             two
             things
             really
             distinct
             ;
             because
             the
             Pressure
             may
             be
             augmented
             ,
             without
             any
             increment
             of
             the
             
               natural
               weight
            
             .
             VVe
             see
             fourthly
             ,
             that
             the
             Pressure
             ,
             or
             Bensil
             of
             a
             Fluid
             ,
             cannot
             affect
             the
             Scale
             of
             a
             Ballance
             ,
             but
             only
             the
             
               natural
               weight
            
             .
             VVe
             see
             fifthly
             ,
             that
             a
             body
             naturally
             heavier
             than
             Water
             ,
             
               weighs
               in
               Water
            
             ,
             because
             the
             stone
             F
             G
             ,
             makes
             the
             Water
             about
             it
             ,
             10
             pound
             heavier
             .
             If
             it
             be
             inquired
             ,
             whether
             bodies
             ,
             that
             are
             naturally
             lighter
             ,
             will
             
               weigh
               in
               Water
            
             ?
             I
             answer
             ,
             if
             they
             be
             of
             any
             sensible
             weight
             ,
             they
             weigh
             ,
             as
             well
             as
             the
             other
             .
             For
             this
             cause
             ,
             I
             except
             Air.
             For
             though
             they
             were
             never
             so
             light
             ,
             in
             respect
             of
             Water
             ,
             yet
             if
             they
             have
             any
             considerable
             gravity
             with
             them
             ,
             they
             will
             make
             the
             Water
             heavier
             ,
             they
             are
             among
             .
             Put
             the
             case
             the
             Body
             were
             a
             Cube
             of
             Timber
             of
             six
             inches
             ,
             weighing
             sixteen
             ounces
             ,
             and
             that
             a
             Cube
             of
             Water
             of
             that
             quantity
             ,
             weighed
             112
             ounces
             .
             Here
             's
             a
             great
             inequality
             ,
             between
             their
             
               natural
               weights
            
             :
             yet
             if
             that
             piece
             of
             Timber
             ,
             were
             made
             to
             exist
             in
             the
             middle
             of
             Water
             ,
             as
             the
             Bladder
             doth
             ,
             it
             would
             make
             it
             16
             ounces
             heavier
             .
             
             The
             reason
             is
             this
             ;
             these
             16
             ounces
             are
             either
             supported
             by
             a
             surface
             of
             Water
             ,
             or
             they
             support
             themselves
             .
             This
             last
             is
             impossible
             .
             If
             the
             VVater
             support
             them
             ,
             then
             must
             they
             make
             the
             said
             VVater
             16
             ounces
             heavier
             .
             Note
             ,
             that
             though
             a
             Body
             naturally
             lighter
             then
             VVater
             ,
             as
             Cork
             ,
             may
             be
             said
             to
             
               weigh
               in
               Water
            
             ,
             that
             's
             to
             say
             ,
             to
             make
             it
             heavier
             ,
             in
             which
             sense
             VVater
             
               weighs
               in
               Water
            
             ,
             because
             if
             you
             add
             a
             pint
             to
             a
             gallon
             ,
             it
             makes
             it
             heavier
             ;
             yet
             if
             you
             take
             a
             piece
             of
             Cork
             ,
             and
             knit
             it
             to
             the
             Scale
             of
             a
             Ballance
             ,
             by
             a
             threed
             ,
             the
             Cork
             hanging
             among
             the
             VVater
             ,
             the
             Scale
             hanging
             above
             in
             the
             Air
             ,
             it
             will
             not
             
               weigh
               in
               Water
            
             ;
             because
             in
             this
             sense
             ,
             no
             Body
             
               weighs
               in
               Water
            
             ,
             but
             that
             which
             is
             naturally
             heavier
             then
             VVater
             ,
             as
             Lead
             ,
             or
             Stone
             .
             In
             this
             sense
             ,
             VVater
             doth
             not
             
               weigh
               in
               Water
            
             ,
             as
             will
             be
             seen
             in
             the
             17
             Experiment
             .
          
        
         
           
             EXPERIMENT
             IX
             .
             Figure
             13.
             
          
           
             Take
             a
             Glass-pipe
             70
             inches
             long
             or
             there-about
             ,
             and
             of
             any
             wideness
             ,
             having
             the
             upper
             end
             H
             ,
             hermetically
             sealed
             ,
             the
             lower
             end
             C
             compleatly
             open
             ,
             and
             fill
             it
             with
             Mercury
             ,
             and
             cause
             a
             Diver
             carry
             it
             down
             to
             the
             ground
             of
             the
             sea
             M
             N
             ,
             where
             I
             suppose
             is
             standing
             the
             Vessel
             A
             B
             D
             E
             with
             stagnant
             Mercury
             ,
             and
             drown
             the
             end
             below
             the
             surface
             A
             B.
             This
             being
             done
             ,
             the
             Mercury
             falls
             from
             the
             upper
             end
             H
             ,
             to
             the
             point
             G
             ,
             and
             there
             halts
             ;
             the
             space
             H
             G
             being
             empty
             .
             For
             understanding
             this
             Experiment
             ,
             I
             shall
             propose
             several
             questions
             ,
             and
             answere
             them
             .
             First
             ,
             what
             's
             the
             reason
             ,
             why
             the
             Mercury
             subsides
             ,
             and
             sinks
             down
             from
             H
             to
             G
             ?
             I
             answer
             ,
             as
             formerly
             
             in
             the
             like
             cases
             ,
             inequality
             of
             weight
             between
             the
             Pondus
             of
             the
             impending
             Quick-silver
             ,
             and
             the
             Potentia
             of
             the
             surface
             ,
             of
             the
             stagnant
             Quick-silver
             D
             C
             E.
             For
             while
             the
             Tub
             is
             compleatly
             full
             ,
             the
             weight
             is
             so
             great
             ,
             that
             the
             surface
             D
             C
             E
             ,
             is
             not
             able
             to
             sustain
             it
             ,
             therefore
             it
             must
             fall
             down
             ,
             seing
             motion
             necessarily
             followes
             in
             Fluids
             ,
             upon
             inequality
             of
             weight
             .
             It
             may
             be
             inquired
             secondly
             ,
             why
             it
             halts
             at
             G
             ,
             58
             inches
             from
             A
             B
             ,
             and
             comes
             no
             further
             down
             ?
             I
             answer
             it
             halts
             at
             G
             ,
             because
             when
             it
             hath
             fallen
             down
             to
             that
             point
             ,
             there
             happens
             equality
             of
             weight
             ,
             between
             the
             suspended
             Pillar
             ,
             and
             the
             foresaid
             surface
             :
             for
             whatever
             weight
             the
             said
             Pillar
             is
             of
             ,
             the
             surface
             on
             which
             it
             rests
             ,
             is
             of
             the
             same
             .
             In
             a
             word
             ,
             the
             Pondus
             of
             the
             one
             ,
             and
             the
             Potentia
             of
             the
             other
             are
             now
             equal
             .
             For
             understanding
             this
             ,
             consider
             according
             to
             the
             25
             Theorem
             ,
             that
             the
             weight
             of
             the
             Element
             of
             Air
             ,
             upon
             the
             surfaces
             of
             waters
             ,
             is
             equivalent
             to
             the
             burden
             of
             34
             foot
             of
             water
             ,
             therefore
             the
             first
             and
             visible
             surface
             of
             this
             Water
             L
             I
             K
             ,
             is
             really
             as
             much
             prest
             ,
             with
             the
             burden
             of
             the
             Atmosphere
             ,
             as
             if
             it
             had
             34
             foot
             of
             Water
             upon
             it
             .
             Consider
             next
             ,
             that
             between
             the
             said
             surface
             ,
             and
             the
             ground
             M
             N
             ,
             are
             34
             foot
             of
             Water
             indeed
             .
             Consider
             thirdly
             ,
             that
             a
             Pillar
             of
             Water
             34
             foot
             high
             ,
             is
             exactly
             of
             the
             same
             weight
             ,
             with
             a
             Pillar
             of
             Mercury
             29
             inches
             high
             ;
             for
             if
             Water
             be
             14
             times
             lighter
             than
             Mercury
             ,
             then
             they
             cannot
             be
             of
             equal
             weight
             ,
             unless
             the
             one
             be
             14
             times
             higher
             than
             the
             other
             .
             Now
             ,
             supposing
             the
             weight
             of
             the
             Air
             upon
             the
             surface
             L
             I
             K
             ,
             to
             be
             equivalent
             to
             34
             foot
             of
             Water
             ,
             or
             (
             which
             is
             the
             same
             thing
             )
             to
             29
             inches
             of
             Mercury
             ,
             the
             surface
             of
             the
             stagnant
             Mercury
             A
             B
             ,
             must
             be
             as
             much
             burdened
             with
             the
             incumbing
             Water
             ,
             and
             the
             Air
             together
             ,
             as
             if
             it
             had
             really
             resting
             upon
             it
             ,
             a
             Pillar
             of
             
             Mercury
             58
             inches
             high
             .
             If
             this
             be
             ,
             then
             it
             follows
             by
             necessity
             ,
             that
             there
             must
             be
             an
             equality
             of
             weight
             ,
             between
             the
             pondus
             of
             the
             Mercury
             in
             the
             Tub
             ,
             and
             the
             potentia
             of
             the
             surface
             D
             C
             E
             ;
             Or
             (
             which
             is
             all
             one
             thing
             )
             that
             the
             part
             C
             ,
             on
             which
             the
             Pillar
             rests
             ,
             is
             no
             more
             burdened
             ,
             than
             the
             part
             D
             or
             E.
             For
             if
             34
             foot
             of
             Water
             ,
             and
             34
             foot
             of
             VVater
             ,
             be
             equivalent
             for
             weight
             ,
             to
             58
             inches
             of
             Mercury
             ,
             then
             must
             the
             part
             D
             and
             E
             ,
             be
             as
             much
             burdened
             with
             the
             said
             weight
             ,
             as
             the
             part
             C
             is
             burdened
             with
             the
             Pillar
             within
             the
             Tub
             ,
             seing
             both
             are
             of
             the
             same
             height
             :
             therefore
             the
             power
             ,
             and
             force
             of
             the
             imaginary
             surface
             of
             the
             stagnant
             Mercury
             D
             C
             E
             ,
             is
             of
             the
             same
             strength
             ,
             with
             the
             weight
             of
             the
             Pillar
             G
             F
             B.
             And
             this
             lets
             us
             see
             the
             reason
             ,
             why
             the
             whole
             70
             inches
             cannot
             be
             suspended
             ;
             for
             if
             the
             outward
             Pressure
             that
             's
             upon
             A
             B
             ,
             be
             but
             equivalent
             to
             the
             Pressure
             of
             58
             ,
             it
             can
             never
             make
             the
             surface
             D
             C
             E
             able
             to
             support
             70.
             
          
           
             To
             make
             it
             evident
             (
             if
             any
             doubt
             )
             that
             the
             Mercury
             is
             suspended
             by
             the
             weight
             of
             the
             Water
             ,
             and
             the
             weight
             of
             the
             Air
             superadded
             ,
             let
             a
             Diver
             bring
             up
             this
             Engine
             to
             the
             top
             of
             the
             Water
             ,
             and
             he
             will
             find
             the
             one
             half
             to
             have
             fallen
             down
             ,
             namely
             from
             G
             to
             F
             ,
             the
             other
             half
             F
             B
             remaining
             .
             And
             if
             it
             were
             possible
             ,
             to
             convey
             this
             Experiment
             to
             the
             top
             of
             the
             Air
             ,
             the
             Bearer
             would
             see
             ,
             the
             remaining
             half
             to
             fall
             down
             likewise
             ,
             and
             become
             level
             with
             A
             B
             ;
             for
             where
             no
             Pressure
             of
             Air
             is
             ,
             there
             can
             be
             no
             Mercury
             suspended
             .
             This
             falling
             down
             ,
             is
             not
             all
             at
             once
             ,
             but
             by
             degrees
             ,
             and
             keeps
             a
             proportion
             with
             the
             Pressure
             of
             the
             Air
             ,
             that
             grows
             less
             and
             less
             ,
             from
             the
             ground
             to
             the
             top
             .
          
           
             From
             this
             Experiment
             we
             see
             first
             ,
             the
             great
             Pressure
             and
             weight
             ,
             the
             Elements
             of
             Air
             and
             Water
             are
             under
             ,
             
             seing
             this
             Water
             ,
             that
             's
             but
             34
             foot
             deep
             ,
             sustains
             the
             Mercury
             between
             G
             and
             F
             ,
             29
             inches
             ,
             as
             much
             between
             F
             and
             E
             ,
             being
             kept
             up
             by
             the
             Pressure
             of
             the
             Air.
             We
             see
             secondly
             ,
             that
             this
             Pressure
             is
             according
             to
             
               Arithmetical
               Progression
            
             ,
             as
             1
             ,
             2
             ,
             3
             ,
             4
             ,
             5.
             because
             in
             going
             down
             the
             first
             14
             inches
             ,
             the
             Mercury
             rises
             one
             inch
             ;
             in
             going
             down
             the
             second
             14
             inches
             ,
             it
             rises
             two
             ;
             in
             going
             down
             the
             third
             14
             inches
             ,
             it
             rises
             three
             ,
             and
             so
             forward
             .
             We
             see
             thirdly
             ,
             though
             a
             VVater
             were
             100
             fathom
             deep
             ,
             yea
             1000
             ,
             yet
             the
             Pressure
             of
             the
             Air
             above
             is
             found
             at
             the
             bottom
             :
             for
             supposing
             this
             Experiment
             were
             100
             fathom
             deep
             ,
             yet
             would
             the
             Air
             from
             above
             have
             influence
             upon
             it
             ,
             to
             sustain
             so
             many
             inches
             of
             the
             Mercurial
             Cylinder
             .
             A
             Diver
             then
             ,
             10
             or
             15
             fathom
             under
             the
             VVater
             ,
             must
             be
             burdened
             with
             the
             weight
             of
             the
             Air
             ,
             as
             well
             as
             with
             the
             weight
             of
             the
             VVater
             ,
             so
             must
             the
             Fishes
             ,
             though
             never
             so
             deep
             .
             We
             see
             fourthly
             ,
             that
             the
             parts
             of
             a
             Fluid
             cannot
             cease
             from
             motion
             ,
             so
             long
             as
             there
             is
             an
             inequality
             of
             weight
             between
             the
             pondus
             and
             the
             potentia
             .
             This
             is
             clear
             from
             the
             falling
             down
             of
             the
             Mercury
             from
             H
             to
             G.
             And
             assoon
             as
             equality
             of
             weight
             happens
             ,
             the
             motion
             ends
             .
             This
             is
             clear
             from
             the
             Mercurie's
             halting
             at
             G.
             Fifthly
             ,
             that
             in
             Mercury
             ,
             as
             well
             as
             in
             Water
             ,
             or
             Air
             ,
             surfaces
             may
             be
             distinguished
             ,
             and
             that
             these
             surfaces
             ,
             are
             endowed
             with
             a
             Potentia
             or
             power
             ,
             begotten
             in
             them
             by
             superior
             and
             extrinsick
             weight
             .
             This
             is
             clear
             from
             the
             imaginary
             surface
             D
             C
             E
             ,
             that
             's
             made
             powerful
             to
             support
             58
             inches
             of
             Mercury
             in
             the
             Tub
             ,
             and
             that
             by
             the
             weight
             and
             Pressure
             of
             the
             Air
             resting
             upon
             A
             B.
             Sixthly
             ,
             that
             ,
             as
             two
             Fluids
             differ
             in
             specifick
             and
             natural
             weight
             ,
             so
             they
             differ
             in
             altitude
             ,
             when
             they
             counterpoise
             one
             another
             .
             This
             is
             clear
             from
             the
             disproportion
             that
             's
             between
             the
             altitude
             
             of
             the
             Mercury
             suspended
             ,
             and
             the
             height
             of
             the
             Water
             ,
             and
             Air
             suspending
             .
             G
             F
             then
             is
             29
             inches
             ,
             and
             the
             deepness
             of
             the
             Water
             from
             K
             to
             N
             is
             34
             foot
             ,
             because
             Water
             is
             naturally
             14
             times
             lighter
             than
             Mercury
             .
             F
             B
             is
             likewise
             29
             inches
             ,
             and
             the
             hight
             of
             the
             Air
             ,
             that
             rests
             upon
             the
             surface
             of
             Water
             is
             six
             or
             seven
             thousand
             fathom
             high
             ;
             because
             Air
             is
             14000
             times
             naturally
             lighter
             than
             Mercury
             .
             Seventhly
             ,
             that
             Fluid
             Bodies
             counterpoise
             one
             another
             ,
             not
             according
             to
             their
             thickness
             and
             breadth
             ,
             but
             only
             according
             to
             their
             altitude
             .
             This
             is
             evident
             ;
             for
             though
             this
             Tub
             were
             never
             so
             wide
             or
             narrow
             ,
             yet
             the
             altitude
             of
             the
             Mercury
             is
             unchangeable
             .
             Hence
             it
             is
             ,
             that
             the
             thickest
             .
             Pillar
             of
             Water
             in
             the
             Ocean
             ,
             is
             not
             able
             to
             suspend
             more
             Mercury
             ,
             than
             the
             slenderest
             ,
             I
             mean
             as
             to
             altitude
             .
             And
             hence
             it
             is
             ,
             that
             the
             smallest
             Cylinder
             of
             Mercury
             ,
             no
             thicker
             than
             a
             silk
             threed
             ,
             is
             able
             to
             counterpoise
             a
             Pillar
             of
             Water
             ,
             of
             any
             thickness
             whatsoever
             .
             We
             may
             conclude
             lastly
             ,
             that
             when
             a
             Diver
             is
             20
             fathom
             under
             the
             Water
             ,
             he
             is
             under
             as
             much
             burden
             ,
             as
             if
             he
             were
             under
             14
             or
             15
             foot
             of
             Quick-silver
             .
             Suppose
             a
             man
             lying
             on
             his
             belly
             ,
             within
             a
             large
             Vessel
             ,
             and
             14
             or
             15
             foot
             of
             Mercury
             poured
             in
             upon
             him
             ,
             surely
             it
             may
             be
             thought
             ,
             that
             such
             a
             burden
             were
             insupportable
             .
             But
             put
             the
             case
             ,
             the
             Diver
             were
             down
             40
             fathom
             ,
             then
             must
             the
             burden
             be
             doubled
             .
             This
             follows
             ,
             because
             if
             a
             Pillar
             of
             Water
             34
             foot
             high
             ,
             with
             the
             weight
             of
             the
             Air
             superadded
             ,
             be
             as
             heavy
             ,
             as
             58
             inches
             of
             Mercury
             ,
             then
             surely
             a
             Pillar
             20
             fathom
             high
             ,
             or
             100
             foot
             ,
             must
             be
             as
             heavy
             as
             170
             inches
             ,
             which
             is
             more
             than
             14
             foot
             .
          
        
         
           
           
             EXPERIMENT
             X.
             Figure
             14.
             
          
           
             AGainst
             the
             former
             Experiment
             ,
             there
             occurres
             some
             difficulties
             ,
             which
             must
             be
             answered
             .
             As
             first
             ,
             if
             it
             be
             the
             Pressure
             of
             the
             Water
             ,
             that
             sustains
             the
             Mercury
             in
             the
             Tub
             (
             see
             the
             13.
             
             Figure
             )
             then
             the
             weight
             of
             the
             said
             Mercury
             ought
             not
             to
             be
             found
             ,
             while
             the
             Tub
             is
             poi●ed
             between
             a
             mans
             Fingers
             .
             But
             so
             it
             is
             ,
             that
             when
             a
             Diver
             grips
             the
             Tub
             about
             the
             middle
             ,
             and
             raises
             it
             a
             little
             from
             the
             bottom
             of
             the
             Vessel
             ,
             he
             not
             only
             finds
             the
             weight
             of
             the
             Tub
             it self
             ,
             but
             the
             weight
             also
             of
             the
             58
             inches
             of
             Mercury
             that
             's
             within
             it
             .
             But
             this
             ought
             not
             to
             be
             ,
             if
             the
             said
             Mercury
             ,
             be
             sustained
             by
             the
             outward
             Water
             .
             In
             a
             word
             ,
             it
             ought
             not
             to
             be
             found
             ,
             because
             the
             said
             Pillar
             of
             Mercury
             ,
             as
             really
             stands
             ,
             and
             rests
             upon
             the
             imaginary
             surface
             D
             C
             E
             ,
             as
             a
             Cylinder
             of
             Brass
             or
             Stone
             ,
             rests
             upon
             a
             plain
             Table
             of
             Timber
             or
             Stone
             .
             If
             then
             ,
             it
             be
             supported
             by
             the
             said
             surface
             ,
             why
             ought
             I
             to
             find
             the
             weight
             of
             it
             ,
             when
             I
             lift
             up
             the
             Pipe
             a
             little
             from
             the
             bottom
             of
             the
             Vessel
             ?
             For
             clearing
             this
             difficulty
             ,
             consider
             ,
             that
             when
             the
             Mercury
             falls
             down
             from
             H
             to
             G
             ,
             it
             leaves
             a
             so●●
             of
             vac●ity
             behind
             it
             ,
             wherein
             there
             is
             neither
             Air
             nor
             Water
             .
             Consider
             secondly
             ,
             that
             for
             this
             cause
             ,
             there
             happens
             an
             unequal
             Pressure
             ;
             the
             top
             of
             the
             Tub
             without
             ,
             being
             burdened
             with
             the
             Pillar
             of
             Water
             I
             H
             ,
             which
             actually
             presseth
             it
             down
             ,
             and
             nothing
             within
             between
             G
             and
             H
             ,
             that
             may
             counterballance
             that
             downward
             Pressure
             .
             These
             things
             being
             considered
             ,
             I
             answer
             to
             the
             difficulty
             and
             say
             ,
             it
             is
             not
             the
             weight
             of
             the
             suspended
             Mercury
             that
             I
             find
             ,
             but
             the
             weight
             of
             the
             Pillar
             of
             Water
             I
             H
             ,
             that
             rests
             upon
             
             the
             top
             of
             the
             Tub.
             If
             it
             be
             said
             ,
             the
             Pressure
             of
             a
             Fluid
             is
             insensible
             ,
             and
             cannot
             be
             found
             .
             I
             answer
             ,
             it
             's
             true
             ,
             when
             the
             Pressure
             is
             equal
             and
             uniform
             ,
             but
             not
             when
             the
             Pressure
             is
             unequal
             ,
             as
             here
             .
             If
             it
             be
             asked
             ,
             how
             comes
             it
             to
             pass
             ,
             that
             the
             Pillar
             of
             Water
             I
             H
             ,
             is
             exactly
             the
             weight
             of
             the
             58
             inches
             of
             Mercury
             ?
             I
             answer
             ,
             besides
             the
             said
             Pillar
             ,
             there
             is
             another
             of
             Air
             ,
             that
             rests
             upon
             the
             top
             of
             it
             ,
             which
             two
             together
             are
             exactly
             the
             weight
             of
             the
             suspended
             Mercury
             ;
             I
             H
             being
             of
             the
             same
             weight
             with
             the
             Mercury
             G
             F
             ,
             and
             the
             foresaid
             Pillar
             of
             Air
             ,
             being
             of
             the
             same
             weight
             with
             the
             Mercury
             F
             B.
             To
             make
             it
             more
             evident
             ,
             remember
             that
             one
             inch
             of
             Mercury
             ,
             is
             exactly
             the
             weight
             of
             14
             inches
             of
             Water
             ;
             and
             that
             one
             inch
             of
             Mercury
             ,
             is
             of
             the
             same
             weight
             with
             14000
             inches
             of
             Air.
             If
             this
             be
             ,
             then
             must
             the
             Pillar
             of
             VVater
             I
             H
             ,
             that
             's
             34
             foot
             high
             ,
             and
             of
             the
             same
             thickness
             with
             the
             29
             inches
             of
             Mercury
             G
             F
             ,
             be
             of
             the
             same
             weight
             with
             it
             ,
             seing
             29
             inches
             are
             to
             be
             found
             14
             times
             in
             34
             foot
             .
             For
             the
             same
             reason
             ,
             is
             the
             Pillar
             of
             Air
             ,
             namely
             S
             I
             ,
             that
             rests
             upon
             the
             top
             of
             the
             Pillar
             of
             VVater
             I
             H
             ,
             of
             the
             same
             weight
             with
             the
             29
             inches
             of
             Mercury
             F
             B.
             For
             after
             a
             just
             reckoning
             ,
             you
             will
             find
             ,
             that
             29
             inches
             will
             be
             found
             14000
             times
             in
             the
             Pillar
             of
             Air
             ,
             that
             rests
             upon
             the
             Pillar
             I
             H.
             Or
             in
             a
             word
             ,
             the
             hight
             of
             the
             Air
             is
             14000
             times
             ,
             29
             inches
             .
          
           
             But
             here
             occurrs
             another
             difficulty
             .
             Let
             us
             suppose
             there
             were
             a
             Tub
             six
             foot
             high
             ,
             one
             inch
             wide
             ,
             having
             the
             sides
             ,
             3
             inches
             thick
             .
             Imagine
             likewise
             the
             said
             Tub
             to
             be
             under
             the
             water
             34
             foot
             ,
             with
             58
             inches
             of
             Mercury
             in
             it
             ,
             as
             is
             represented
             in
             this
             14
             Figure
             .
             This
             being
             supposed
             ▪
             the
             Pillar
             of
             Water
             E
             A
             F
             C
             G
             D
             ,
             must
             be
             far
             heavier
             ,
             than
             the
             58
             inches
             of
             Mercury
             H
             B.
             The
             reason
             is
             clear
             ,
             
             because
             the
             said
             Pillar
             ,
             is
             not
             only
             34
             foot
             high
             ,
             but
             as
             thick
             ,
             as
             the
             Diameter
             of
             the
             Tub
             ,
             whose
             sides
             are
             three
             inches
             thick
             .
             I
             answer
             ,
             the
             whole
             weight
             of
             that
             Water
             E
             A
             F
             C
             G
             D
             is
             not
             found
             ,
             while
             a
             man
             poises
             the
             Tub
             between
             his
             fingers
             ,
             but
             only
             the
             weight
             of
             the
             part
             G
             A
             ,
             which
             is
             exactly
             the
             weight
             of
             the
             Mercury
             H
             B.
             But
             here
             occurrs
             the
             great
             question
             ,
             namely
             ,
             why
             I
             find
             only
             the
             weight
             of
             the
             Water
             G
             A
             ,
             and
             nothing
             of
             the
             weight
             of
             the
             Water
             ,
             C
             E
             ,
             or
             D
             F
             ?
             I
             answer
             ,
             I
             cannot
             find
             the
             Pressure
             of
             the
             Water
             C
             E
             ,
             because
             it
             is
             counterpoised
             with
             the
             upward
             Pressure
             of
             the
             Water
             I
             K.
             And
             for
             the
             same
             reason
             ,
             I
             cannot
             find
             the
             weight
             of
             the
             Water
             D
             F
             ,
             because
             it
             is
             counterpoised
             by
             L
             M
             ;
             but
             because
             there
             is
             nothing
             between
             H
             and
             A
             ,
             to
             counterpoise
             the
             downward
             Pressure
             of
             the
             Water
             G
             A
             ,
             therefore
             I
             find
             that
             .
             If
             it
             be
             objected
             ,
             that
             the
             Water
             I
             K
             ,
             cannot
             counterpoise
             the
             Water
             C
             E
             ,
             because
             the
             one
             is
             farder
             down
             than
             the
             other
             ,
             and
             consequently
             under
             a
             greater
             Pressure
             ,
             than
             the
             other
             .
             I
             answer
             ,
             though
             I
             K
             be
             stronger
             than
             C
             E
             ,
             yet
             a
             compensation
             is
             made
             by
             the
             weight
             of
             the
             Tub.
             For
             understanding
             this
             ,
             let
             us
             suppose
             the
             Water
             C
             E
             ,
             and
             D
             F
             ,
             to
             press
             downward
             with
             the
             weight
             of
             six
             pound
             ,
             and
             the
             Water
             K
             I
             ,
             and
             L
             M
             ,
             to
             press
             upward
             with
             the
             weight
             of
             ten
             pound
             ,
             there
             being
             four
             pound
             in
             difference
             .
             Suppose
             next
             ,
             the
             Tub
             to
             weigh
             in
             the
             Air
             ten
             pound
             ,
             and
             in
             the
             Water
             only
             six
             pound
             .
             If
             this
             be
             ,
             then
             according
             to
             the
             eighth
             Experiment
             ,
             and
             eighteenth
             Theorem
             ,
             four
             pound
             weight
             of
             the
             Tub
             must
             rest
             upon
             the
             surface
             I
             L.
             And
             if
             this
             be
             ,
             then
             must
             the
             Water
             I
             K
             ,
             and
             L
             M
             ,
             be
             four
             pound
             weaker
             with
             the
             Tub
             ,
             than
             without
             it
             ,
             and
             must
             only
             have
             six
             pound
             of
             upward
             Pressure
             .
          
           
           
           
           
           
             From
             these
             Experiments
             we
             conclude
             first
             ,
             the
             truth
             of
             the
             tenth
             Theorem
             ,
             namely
             that
             the
             weight
             of
             a
             Fluid
             is
             only
             found
             by
             sense
             ,
             when
             the
             Pressure
             is
             not
             uniform
             ,
             and
             equal
             .
             This
             is
             evident
             from
             our
             finding
             the
             weight
             of
             the
             Pillar
             of
             Water
             I
             H
             ,
             as
             in
             the
             13
             Figure
             .
             We
             conclude
             secondly
             ,
             that
             in
             all
             Fluids
             ,
             there
             is
             a
             pondus
             and
             a
             potentia
             ;
             as
             is
             clear
             from
             the
             pondus
             of
             Water
             E
             A
             F
             C
             G
             D
             ;
             that
             presseth
             down
             the
             Tub
             ,
             and
             the
             potentia
             of
             the
             Water
             I
             K
             L
             M
             ,
             that
             presseth
             up
             the
             same
             Tub.
             We
             see
             thirdly
             ,
             that
             there
             cannot
             be
             two
             surfaces
             of
             Water
             differing
             in
             altitude
             ,
             but
             they
             must
             differ
             in
             degrees
             of
             Pressure
             :
             because
             the
             surface
             E
             A
             F
             ,
             is
             weaker
             ,
             than
             the
             surface
             I
             L
             ,
             that
             being
             higher
             than
             this
             .
             We
             see
             fourthly
             ,
             that
             two
             surfaces
             differing
             in
             strength
             ,
             may
             be
             made
             equal
             by
             some
             Body
             or
             other
             interveening
             ;
             because
             ,
             though
             I
             L
             be
             stronger
             than
             E
             A
             F
             ,
             yet
             seing
             it
             supports
             four
             pound
             of
             the
             Tub
             ,
             it
             presseth
             up
             with
             no
             more
             force
             ,
             than
             E
             A
             F
             ,
             presseth
             down
             with
             .
             We
             see
             fifthly
             ,
             that
             a
             Body
             suspended
             in
             a
             Fluid
             ,
             as
             in
             Air
             ,
             or
             in
             VVater
             ,
             may
             have
             one
             part
             of
             it
             prest
             equally
             with
             that
             Fluid
             ,
             and
             another
             part
             unequally
             :
             this
             is
             evident
             ,
             because
             the
             parts
             E
             and
             F
             ,
             are
             equally
             prest
             with
             the
             Pillars
             C
             E
             ,
             and
             D
             F
             ,
             seing
             this
             Pressure
             is
             counterpoised
             with
             the
             Pressure
             of
             VVater
             ,
             I
             K
             ,
             and
             L
             M.
             But
             the
             middle
             part
             of
             the
             Tub
             A
             ,
             is
             unequally
             prest
             ,
             seing
             it
             is
             prest
             downward
             ,
             with
             the
             VVater
             G
             A
             ,
             but
             not
             prest
             upward
             with
             the
             Mercury
             B
             H.
             VVe
             see
             sixthly
             ,
             that
             whatever
             be
             the
             thickness
             of
             a
             Pillar
             of
             a
             Fluid
             ;
             yet
             no
             more
             of
             its
             weight
             is
             found
             ,
             or
             is
             sensible
             ,
             than
             the
             part
             ,
             which
             presseth
             unequally
             :
             for
             though
             E
             A
             F
             C
             G
             D
             ,
             be
             a
             Pillar
             six
             or
             seven
             inches
             thick
             ,
             yet
             no
             more
             of
             the
             Pressure
             is
             sensible
             ,
             than
             what
             comes
             from
             
             G
             A.
             VVe
             see
             seventhly
             ,
             that
             a
             Body
             equally
             prest
             with
             a
             Fluid
             ,
             weighs
             less
             ,
             but
             a
             Body
             unequally
             prest
             ▪
             weighs
             none
             at
             all
             .
             This
             is
             clear
             in
             many
             particulars
             ;
             for
             a
             Stone
             weighed
             in
             VVater
             ,
             loseth
             not
             all
             the
             weight
             ,
             but
             a
             pa●t
             ,
             because
             it
             is
             equally
             pressed
             .
             But
             a
             Body
             unequally
             prest
             ,
             as
             is
             the
             Mercury
             H
             B
             ,
             hath
             no
             weight
             at
             all
             ,
             as
             it
             now
             stands
             .
             For
             understanding
             this
             ,
             you
             must
             consider
             ,
             that
             the
             whole
             weight
             of
             it
             tests
             upon
             the
             surface
             of
             VVater
             I
             L.
             Therefore
             though
             it
             could
             be
             weighed
             by
             a
             string
             ,
             passing
             from
             the
             top
             H
             ,
             to
             a
             Ballance
             existing
             in
             the
             Air
             ;
             yet
             the
             said
             Ballance
             would
             find
             none
             of
             its
             weight
             ,
             seing
             it
             is
             wholly
             suspended
             by
             the
             VVater
             ;
             but
             a
             Stone
             so
             weighed
             ,
             is
             only
             suspended
             in
             part
             ,
             by
             the
             Water
             .
          
        
         
           
             EXPERIMENT
             XI
             .
             Figure
             15.
             
          
           
             A
             M
             Z
             C
             is
             a
             Water
             15
             foot
             deep
             .
             A
             B
             a
             Glass-tub
             14
             inches
             long
             ,
             and
             full
             of
             Mercury
             .
             B
             C
             a
             Pillar
             of
             Water
             13
             foot
             ,
             10
             inches
             high
             ,
             thorow
             whose
             middle
             goes
             a
             string
             to
             the
             scale
             of
             the
             Ballance
             K
             ,
             existing
             in
             the
             Air.
             D
             E
             is
             a
             Tub
             full
             of
             Mercury
             28
             inches
             long
             ,
             with
             a
             Pillar
             of
             Water
             above
             it
             E
             F
             ,
             12
             foot
             and
             eight
             inches
             .
             G
             H
             a
             Tub
             42
             inches
             long
             ,
             with
             a
             Pillar
             of
             Water
             above
             it
             H
             I
             ,
             11
             foot
             and
             six
             inches
             high
             .
             And
             lastly
             ,
             A
             D
             G
             S
             M
             an
             imaginary
             surface
             ,
             15
             foot
             deep
             .
             This
             Experiment
             is
             brought
             hither
             ,
             to
             demonstrate
             that
             a
             heavy
             Body
             ,
             weighs
             as
             much
             in
             Water
             ,
             as
             in
             Air
             ,
             which
             is
             point-blank
             to
             the
             common
             received
             opinion
             ,
             and
             destructive
             of
             the
             18
             Theorem
             .
             To
             evince
             this
             ,
             I
             must
             suppose
             the
             14
             
             inches
             of
             Mercury
             in
             the
             Tub
             A
             B
             to
             weigh
             14
             ounce
             ;
             and
             the
             28
             inches
             of
             Mercury
             D
             E
             ,
             to
             weigh
             28
             ounce
             ;
             the
             42
             inches
             G
             H
             to
             weigh
             (
             I
             mean
             in
             the
             Air
             )
             42
             ounce
             .
             Now
             I
             say
             ,
             to
             make
             a
             just
             equipondium
             between
             the
             two
             Scales
             K
             and
             L
             ,
             there
             must
             be
             14
             ounce
             put
             into
             the
             Scale
             L.
             If
             after
             this
             manner
             you
             weigh
             the
             Tub
             and
             Mercury
             D
             E
             ,
             28
             ounces
             will
             be
             required
             in
             the
             Scale
             L
             ,
             and
             42
             ,
             if
             you
             weigh
             the
             Tub
             and
             Mercury
             G
             H.
             For
             proving
             this
             Doctrine
             ,
             I
             must
             appeal
             to
             Experience
             ,
             which
             will
             not
             fail
             in
             this
             .
             If
             you
             reply
             ,
             and
             say
             ,
             upon
             supposition
             the
             Tub
             and
             Mercury
             G
             H
             ,
             were
             a
             solid
             piece
             of
             brass
             ,
             or
             iron
             thus
             suspended
             in
             the
             Water
             ,
             ought
             it
             not
             to
             weigh
             less
             here
             than
             in
             the
             Air
             ,
             even
             as
             much
             less
             ,
             as
             is
             the
             weight
             of
             the
             quantity
             of
             Water
             ,
             it
             puts
             out
             of
             its
             place
             :
             why
             then
             should
             not
             the
             Pipe
             H
             G
             ,
             with
             the
             Mercury
             in
             it
             ,
             do
             the
             same
             ,
             seing
             there
             is
             no
             apparent
             difference
             between
             them
             ,
             as
             to
             this
             ?
          
           
             But
             to
             leave
             this
             ,
             which
             will
             appear
             afterwards
             ,
             and
             to
             let
             the
             Reader
             see
             the
             truth
             of
             the
             18
             Theorem
             ,
             I
             affirm
             ,
             't
             is
             not
             the
             weight
             of
             the
             14
             ounces
             of
             Mercury
             A
             B
             ,
             that
             burdens
             the
             scale
             of
             the
             Ballance
             K
             ,
             and
             that
             makes
             a
             counterpoise
             with
             the
             14
             ounces
             of
             Stone
             ,
             or
             Lead
             ,
             that
             's
             in
             the
             scale
             L.
             What
             then
             is
             it
             ,
             you
             say
             ?
             I
             answer
             ,
             't
             is
             14
             ounces
             of
             the
             Pillar
             of
             Water
             B
             C
             that
             does
             this
             .
             Neither
             doth
             the
             weight
             of
             the
             28
             ounces
             of
             Mercury
             D
             E
             burden
             the
             Ballance
             ,
             but
             only
             28
             ounces
             of
             the
             Water
             E
             F.
             Neither
             doth
             the
             Ballance
             support
             the
             weight
             of
             the
             42
             ounces
             of
             Mercury
             G
             H
             ,
             but
             it
             is
             only
             burdened
             with
             42
             ounces
             of
             the
             Water
             H
             I.
             The
             reason
             is
             most
             evident
             ,
             because
             according
             to
             the
             Principles
             of
             the
             Hydrostaticks
             already
             laid
             down
             ,
             the
             Cylinder
             of
             Mercury
             A
             B
             ,
             within
             the
             Tub
             A
             B
             ,
             rests
             immediatly
             upon
             the
             imaginary
             surface
             
             of
             the
             Water
             A
             D
             G
             ,
             and
             therefore
             cannot
             burden
             the
             scale
             in
             any
             wise
             .
             The
             same
             is
             true
             of
             the
             other
             two
             Cylinders
             of
             Mercury
             .
             But
             in
             this
             I
             find
             small
             difficulty
             .
             The
             greater
             is
             ,
             how
             to
             make
             it
             out
             ,
             that
             the
             scale
             K
             ,
             supports
             14
             ounces
             of
             the
             Water
             B
             C
             ,
             and
             28
             of
             the
             Water
             E
             F
             ,
             and
             42
             of
             the
             Water
             H
             I.
             To
             make
             this
             seem
             probable
             ,
             consider
             first
             ,
             as
             was
             noted
             ,
             that
             this
             VVater
             is
             15
             foot
             deep
             ,
             and
             consequently
             the
             Pillar
             of
             VVater
             B
             C
             ,
             13
             foot
             10
             inches
             .
             The
             VVater
             E
             F
             12
             foot
             eight
             inches
             .
             And
             H
             I
             ,
             11
             foot
             and
             a
             half
             .
             Consider
             secondly
             ,
             though
             this
             be
             true
             ,
             yet
             we
             must
             count
             the
             Pillar
             of
             VVater
             Z
             M
             49
             foot
             high
             .
             The
             reason
             is
             evident
             ,
             because
             the
             Pressure
             of
             the
             Air
             ,
             upon
             the
             surface
             of
             all
             Waters
             (
             according
             to
             the
             25
             Theorem
             )
             is
             equivalent
             to
             34
             foot
             of
             Water
             :
             this
             then
             being
             added
             to
             15
             ,
             makes
             49
             ,
             and
             by
             this
             reckoning
             the
             Water
             B
             C
             is
             47
             foot
             ten
             inches
             :
             the
             Water
             E
             F
             46
             foot
             eight
             inches
             :
             And
             lastly
             ,
             the
             Water
             H
             I
             45
             foot
             six
             inches
             .
             Thirdly
             ,
             for
             easie
             counting
             ,
             I
             must
             suppose
             the
             whole
             Cylinder
             Z
             M
             to
             weigh
             42
             ounces
             ,
             every
             14
             inches
             one
             ounce
             :
             and
             consequently
             the
             Water
             B
             C
             to
             weigh
             41
             ounces
             ;
             the
             Water
             E
             F
             to
             weigh
             40
             ounces
             ;
             the
             Water
             H
             I
             39
             ounces
             .
             Note
             ,
             that
             in
             Physical
             demonstrations
             ,
             't
             is
             not
             needful
             to
             use
             Mathematical
             strictness
             in
             counting
             ;
             and
             so
             leaving
             out
             fractions
             ,
             we
             shall
             onely
             use
             round
             numbers
             .
             Consider
             fourthly
             ,
             that
             in
             all
             Fluids
             ,
             as
             hath
             been
             frequently
             marked
             ,
             there
             is
             a
             pondus
             and
             potentia
             ,
             the
             Water
             B
             C
             being
             the
             pondus
             ,
             and
             the
             Mercury
             A
             B
             the
             potentia
             ,
             the
             one
             striving
             to
             press
             down
             the
             Tub
             ,
             the
             other
             striving
             to
             press
             it
             up
             .
             Consider
             fifthly
             ,
             that
             by
             how
             much
             the
             more
             a
             Body
             suspended
             in
             a
             Fluid
             is
             pressed
             up
             ,
             by
             so
             much
             the
             less
             the
             weight
             that
             presseth
             it
             down
             is
             fo●nd
             :
             and
             contrariwise
             ,
             
             by
             how
             much
             the
             less
             it
             is
             pressed
             up
             ,
             by
             so
             much
             the
             more
             the
             Pressure
             above
             is
             found
             .
             Consider
             sixthly
             ,
             the
             less
             that
             a
             surface
             of
             Water
             is
             burdened
             ,
             the
             more
             able
             it
             is
             to
             counterballance
             the
             opposite
             Pressure
             ,
             and
             the
             more
             it
             is
             burdened
             ,
             it
             is
             the
             less
             able
             .
             Consider
             seventhly
             ,
             that
             the
             Mercury
             A
             B
             ,
             (
             which
             is
             evident
             in
             all
             Fluids
             )
             not
             only
             presseth
             downward
             ,
             and
             burdens
             the
             surface
             A
             D
             G
             ,
             but
             also
             presseth
             upward
             ,
             and
             therefore
             actually
             endeavours
             to
             th●ust
             up
             the
             Tub
             ;
             and
             so
             it
             is
             ,
             that
             the
             Tub
             is
             pressed
             between
             two
             ,
             namely
             between
             the
             Water
             C
             B
             ,
             and
             the
             Mercury
             within
             it
             .
          
           
             Now
             from
             these
             considerations
             I
             say
             ,
             the
             scale
             K
             ,
             must
             support
             ,
             and
             bear
             up
             14
             ounce
             of
             the
             Water
             B
             C
             :
             for
             seing
             the
             Mercury
             is
             supported
             by
             the
             surface
             of
             VVater
             on
             which
             it
             rests
             ,
             it
             cannot
             by
             any
             means
             burden
             the
             ballance
             with
             its
             weight
             ;
             and
             seing
             it
             actually
             presseth
             up
             the
             Tub
             ,
             (
             according
             to
             the
             seventh
             consideration
             )
             it
             must
             so
             much
             the
             more
             counterpoise
             (
             according
             to
             the
             sixth
             )
             the
             opposite
             Pressure
             of
             the
             VVater
             B
             C
             ,
             and
             consequently
             diminish
             the
             weight
             of
             it
             :
             so
             that
             the
             Ballance
             cannot
             support
             the
             whole
             ,
             but
             a
             part
             .
             For
             according
             to
             what
             degrees
             of
             force
             ,
             the
             Mercury
             presseth
             up
             the
             Tub
             with
             ,
             according
             to
             the
             same
             ,
             must
             the
             Pressure
             upon
             the
             top
             of
             the
             Tub
             be
             diminished
             ,
             and
             so
             if
             the
             Mercury
             press
             up
             the
             Tub
             with
             the
             force
             of
             27
             ounce
             ,
             the
             VVater
             B
             C
             must
             press
             it
             down
             with
             14
             ounce
             only
             ,
             and
             so
             the
             Cylinder
             B
             C
             ,
             that
             weighs
             really
             41
             ounce
             ,
             must
             press
             the
             top
             of
             this
             Tub
             only
             with
             14
             ,
             which
             14
             ounce
             really
             counterpoiseth
             ,
             the
             14
             ounce
             of
             Stone
             in
             the
             Scale
             L.
             But
             how
             is
             it
             made
             out
             ,
             that
             the
             Mercury
             A
             B
             ,
             presseth
             up
             with
             27
             ounce
             ?
             For
             understanding
             this
             ,
             remember
             ,
             that
             the
             VVater
             is
             49
             foot
             high
             ,
             taking
             in
             the
             Pressure
             of
             the
             Air
             ,
             and
             that
             a
             
             VVater
             of
             that
             deepness
             is
             able
             to
             support
             41
             inches
             of
             Mercury
             ,
             every
             inch
             weighing
             one
             ounce
             .
             For
             if
             14
             of
             Water
             ,
             be
             able
             to
             support
             one
             of
             Mercury
             ,
             49
             foot
             ,
             or
             567
             inches
             ,
             must
             support
             41.
             
             If
             then
             ,
             the
             part
             of
             the
             surface
             A
             ,
             be
             able
             to
             weigh
             41
             ,
             it
             must
             have
             of
             upward
             Pressure
             27
             ounces
             ,
             seing
             it's
             counterpoised
             
               de
               facto
            
             only
             with
             14.
             
             Take
             notice
             ,
             that
             in
             the
             Hydrostaticks
             ,
             the
             word
             pressing
             ,
             or
             weighing
             ,
             as
             really
             and
             truly
             signifies
             a
             weighing
             up
             ,
             as
             a
             weighing
             down
             ,
             seing
             it
             is
             no
             less
             essential
             to
             Fluid
             Bodies
             to
             move
             upward
             ,
             than
             downward
             ,
             and
             that
             with
             equal
             force
             ,
             and
             weight
             .
             According
             to
             this
             reasoning
             ,
             the
             Ballance
             supports
             28
             ounces
             of
             the
             Water
             E
             F
             ,
             (
             Imagine
             the
             second
             Tub
             to
             be
             suspended
             as
             the
             first
             )
             seing
             the
             Cylinder
             of
             Mercury
             D
             E
             ,
             presseth
             up
             the
             Tub
             only
             with
             the
             weight
             of
             12
             ounce
             ,
             which
             28
             ounce
             ,
             really
             counterpoiseth
             the
             28
             ounce
             of
             Stone
             in
             the
             Scale
             L.
             But
             why
             doth
             the
             Mercury
             A
             B
             press
             up
             with
             27
             ounce
             ,
             and
             the
             Mercury
             D
             E
             with
             12
             ?
             For
             answer
             ,
             remember
             ,
             (
             according
             to
             the
             sixth
             consideration
             )
             the
             shorter
             a
             Cylinder
             of
             Mercury
             is
             ,
             the
             surface
             upon
             which
             it
             rests
             ,
             is
             the
             stronger
             ,
             and
             more
             able
             to
             press
             it
             up
             ;
             and
             contrariwise
             ,
             the
             longer
             it
             is
             ,
             the
             surface
             is
             the
             more
             unable
             and
             weak
             :
             therefore
             .
             A
             B
             being
             shorter
             ,
             and
             lighter
             than
             D
             E
             ,
             the
             surface
             of
             Water
             must
             press
             it
             up
             with
             greater
             force
             :
             so
             that
             if
             the
             said
             surface
             A
             M
             ,
             be
             able
             to
             press
             up
             the
             Mercury
             A
             B
             with
             27
             ounce
             ,
             it
             must
             press
             up
             the
             Mercury
             D
             E
             only
             with
             12
             ounce
             .
             According
             to
             this
             rule
             ,
             if
             the
             Mercury
             A
             B
             were
             15
             inches
             high
             ,
             it
             would
             press
             up
             only
             with
             26
             ounce
             ,
             if
             it
             were
             16
             ,
             with
             25
             :
             if
             17
             ,
             with
             24
             :
             if
             18
             ,
             with
             23
             ,
             and
             so
             forward
             .
             This
             leads
             us
             to
             a
             clear
             discovery
             of
             all
             the
             secrets
             here
             :
             for
             if
             the
             Mercury
             A
             B
             ,
             thrust
             up
             the
             Pipe
             ,
             with
             the
             weight
             of
             27
             ounce
             ,
             then
             
             must
             the
             Scale
             K
             ,
             be
             eased
             of
             so
             much
             weight
             ,
             and
             so
             much
             must
             be
             subtracted
             from
             L.
             Now
             let
             us
             imagine
             the
             Pipe
             A
             B
             ,
             to
             be
             empty
             both
             of
             Air
             ,
             Water
             ,
             and
             Mercury
             :
             in
             this
             case
             41
             ounce
             must
             be
             in
             the
             Scale
             L
             ,
             to
             counterpoise
             it
             ,
             seing
             the
             whole
             Cylinder
             B
             C
             ,
             that
             weighs
             so
             much
             ,
             does
             now
             really
             counterpoise
             it
             .
             Let
             us
             imagine
             next
             ,
             these
             14
             inches
             of
             Mercury
             to
             rise
             ,
             and
             fill
             the
             Tub
             A
             B
             :
             in
             this
             case
             ,
             there
             happens
             a
             great
             alteration
             ;
             because
             the
             rising
             of
             them
             ,
             are
             really
             equivalent
             to
             the
             subtracting
             of
             27
             ounce
             from
             the
             Scale
             L
             ;
             and
             the
             reason
             is
             ,
             because
             by
             so
             rising
             and
             filling
             the
             Tub
             ,
             they
             thrust
             up
             the
             said
             Tub
             ,
             and
             by
             this
             means
             easeth
             the
             Scale
             K
             ,
             of
             so
             much
             weight
             .
             Now
             this
             Scale
             being
             eased
             ,
             you
             must
             of
             necessity
             take
             out
             from
             L
             27
             ounce
             for
             making
             a
             new
             counterpoise
             .
          
           
             And
             lastly
             ,
             the
             Scale
             K
             must
             support
             the
             whole
             weight
             of
             the
             Water
             H
             I
             ,
             which
             is
             39
             ounce
             ,
             nothing
             remaining
             to
             counterballance
             this
             downward
             Pressure
             ,
             and
             consequently
             to
             ease
             the
             Ballance
             .
             How
             then
             is
             it
             counterpoised
             ?
             For
             clearing
             this
             ,
             you
             must
             remember
             that
             this
             Water
             ,
             that
             's
             really
             15
             foot
             deep
             ,
             must
             be
             reckoned
             (
             as
             I
             said
             )
             49
             ,
             because
             of
             the
             Pressure
             of
             the
             Air
             upon
             the
             top
             ,
             that
             's
             equivalent
             to
             34.
             
             If
             then
             it
             be
             so
             ,
             it
             cannot
             raise
             Mercury
             higher
             in
             a
             Tub
             than
             42
             inches
             ;
             the
             one
             being
             14
             times
             heavier
             than
             the
             other
             :
             so
             that
             if
             14
             inches
             of
             Water
             ,
             cannot
             raise
             Mercury
             higher
             than
             one
             inch
             ,
             49
             foot
             cannot
             raise
             it
             higher
             ,
             than
             42
             inches
             :
             for
             as
             14
             inches
             ,
             are
             to
             one
             inch
             ;
             so
             is
             49
             foot
             to
             three
             foot
             and
             an
             half
             ,
             which
             is
             42
             inches
             .
             Now
             I
             say
             ,
             the
             whole
             weight
             of
             the
             Water
             H
             I
             ,
             rests
             upon
             the
             top
             of
             the
             Tub
             ,
             and
             so
             presseth
             down
             the
             Scale
             K
             ,
             to
             which
             you
             must
             imagine
             this
             Tub
             ,
             knit
             by
             a
             string
             ,
             as
             the
             former
             was
             ,
             nothing
             remaining
             to
             
             counterpoise
             this
             downward
             Pressure
             :
             for
             the
             top
             of
             the
             Mercurial
             Cylinder
             being
             raised
             as
             high
             within
             the
             Pipe
             ,
             as
             the
             surface
             of
             Water
             D
             G
             S
             ,
             is
             able
             to
             raise
             it
             ,
             the
             said
             top
             can
             impress
             no
             force
             upon
             the
             Tub
             within
             ,
             to
             thrust
             it
             up
             ,
             and
             so
             to
             ease
             the
             Scale
             K.
             For
             example
             ,
             when
             a
             man
             erects
             upon
             his
             hand
             a
             Cylinder
             of
             Timber
             ,
             or
             any
             such
             like
             thing
             ,
             which
             is
             the
             outmost
             he
             can
             support
             ,
             he
             will
             not
             be
             able
             to
             impress
             any
             impulse
             ,
             upon
             the
             seiling
             of
             a
             room
             above
             his
             head
             ;
             but
             if
             so
             be
             ,
             in
             stead
             of
             that
             taken
             away
             ,
             there
             be
             one
             lighter
             erected
             ,
             which
             he
             is
             able
             to
             command
             ,
             he
             can
             easily
             thrust
             up
             the
             seiling
             at
             his
             pleasure
             .
             Just
             so
             it
             is
             here
             ;
             for
             the
             42
             inches
             of
             Mercury
             ,
             being
             the
             outmost
             ,
             that
             the
             surface
             of
             Water
             D
             G
             S
             is
             able
             to
             bear
             ,
             it
             cannot
             impress
             any
             impulse
             therewith
             upon
             the
             top
             of
             the
             Tub
             within
             :
             but
             easily
             can
             the
             Cylinder
             D
             E
             impress
             an
             impulse
             ,
             and
             more
             easily
             the
             Cylinder
             A
             B
             ,
             seing
             they
             are
             lighter
             ,
             and
             so
             more
             powerful
             .
             To
             evidence
             this
             a
             little
             more
             ,
             let
             us
             imagine
             two
             things
             ,
             first
             ,
             the
             Tub
             G
             H
             to
             be
             empty
             ,
             as
             if
             vacuity
             were
             in
             it
             .
             In
             this
             case
             the
             top
             of
             the
             Tub
             ought
             to
             bear
             the
             whole
             burden
             of
             the
             Water
             ,
             and
             consequently
             the
             Ballance
             to
             bear
             it
             also
             :
             because
             there
             is
             not
             a
             potentia
             within
             the
             Tub
             ,
             to
             counterpoise
             this
             pondus
             .
             Next
             ,
             let
             us
             imagine
             the
             Tub
             to
             be
             only
             full
             of
             Water
             :
             according
             to
             this
             supposition
             ,
             the
             Ballance
             cannot
             be
             in
             the
             least
             part
             burdened
             ;
             because
             the
             Water
             within
             the
             Pipe
             ,
             presseth
             it
             up
             with
             as
             much
             force
             ,
             as
             the
             Water
             I
             H
             presseth
             it
             down
             :
             and
             if
             any
             thing
             should
             burden
             the
             Ballance
             ,
             it
             would
             be
             only
             the
             weight
             of
             the
             Pipe
             ,
             that
             's
             not
             considerable
             .
          
           
             From
             what
             is
             demonstrated
             ,
             we
             see
             first
             ,
             that
             though
             this
             Experiment
             would
             seem
             to
             prove
             at
             the
             first
             ,
             that
             a
             heavy
             Body
             weighs
             as
             much
             in
             the
             Water
             ,
             as
             it
             doth
             in
             the
             
             Air
             ,
             because
             the
             whole
             weight
             of
             the
             Mercury
             A
             B
             is
             found
             in
             the
             scale
             L
             ,
             yet
             't
             is
             not
             so
             ,
             because
             the
             14
             ounce
             of
             Stone
             L
             ,
             doth
             not
             counterpoise
             any
             of
             the
             Mercury
             A
             B
             ,
             but
             14
             ounce
             of
             the
             Pillar
             of
             Water
             B
             C.
             Secondly
             ,
             there
             's
             here
             a
             clear
             ground
             ,
             for
             asserting
             a
             pondus
             and
             a
             potentia
             in
             Fluids
             ;
             because
             this
             Tub
             A
             B
             ,
             is
             prest
             down
             with
             the
             VVater
             B
             C
             ,
             and
             prest
             up
             with
             the
             Mercury
             within
             it
             .
             Thirdly
             ,
             there
             's
             here
             a
             clear
             ground
             for
             asserting
             the
             Pressure
             of
             VVater
             ,
             even
             in
             its
             own
             place
             ;
             because
             the
             Water
             B
             C
             ,
             counterpoises
             by
             it's
             weight
             ,
             the
             14
             ounce
             of
             Stone
             L.
             Fourthly
             ,
             we
             see
             an
             excellent
             way
             for
             finding
             the
             weight
             of
             any
             Cylinder
             of
             Water
             ;
             for
             whatever
             be
             the
             weight
             of
             the
             Mercury
             in
             the
             Tub
             ,
             the
             Cylinder
             of
             Water
             ,
             that
             rests
             upon
             the
             top
             ,
             will
             be
             of
             the
             same
             weight
             exactly
             ;
             this
             is
             evident
             in
             comparing
             the
             weight
             of
             the
             Mercury
             G
             H
             ,
             with
             the
             weight
             of
             the
             Water
             H
             I.
             Fifthly
             ,
             that
             whatever
             be
             the
             height
             ,
             and
             weight
             of
             a
             Pillar
             of
             Water
             ,
             yet
             the
             Ballance
             can
             sustain
             no
             more
             of
             it
             ,
             than
             the
             just
             weight
             of
             the
             Mercury
             :
             this
             is
             also
             evident
             ,
             because
             the
             scale
             of
             the
             Ballance
             ,
             supports
             no
             more
             of
             the
             weight
             of
             the
             Water
             B
             C
             ,
             than
             the
             just
             weight
             of
             the
             Mercury
             A
             B.
             We
             see
             sixthly
             ,
             the
             further
             down
             a
             Pipe
             with
             Mercury
             goes
             through
             Water
             ,
             the
             greater
             is
             the
             Pressure
             it
             makes
             upon
             the
             top
             of
             the
             Tub
             within
             :
             for
             put
             the
             case
             ,
             this
             were
             100
             foot
             deep
             ,
             the
             Mercury
             G
             H
             ,
             that
             wants
             all
             upward
             Pressure
             now
             ,
             would
             press
             up
             the
             Tub
             with
             40
             ounce
             :
             the
             Mercury
             D
             E
             with
             55
             ,
             and
             the
             Mercury
             A
             B
             with
             70.
             
             We
             see
             seventhly
             ,
             the
             shorter
             a
             Cylinder
             of
             Mercury
             be
             ,
             it
             is
             the
             stronger
             in
             pressing
             ;
             and
             longer
             it
             be
             ,
             it
             is
             the
             weaker
             ;
             for
             there
             's
             more
             strength
             in
             A
             B
             ,
             than
             in
             D
             E.
             We
             see
             eighthly
             ,
             that
             the
             strength
             decayes
             ,
             and
             grows
             ,
             according
             to
             
               Arithmetical
               progression
            
             ,
             as
             1
             ,
             2
             ,
             3
             ,
             4
             ;
             because
             
             if
             you
             make
             the
             Cylinder
             G
             H
             41
             ,
             that
             's
             now
             42
             ,
             it
             presseth
             up
             with
             one
             ounce
             .
             Make
             it
             40
             inches
             ,
             it
             will
             press
             up
             with
             two
             ounces
             of
             weight
             .
             Make
             it
             39
             ,
             it
             presseth
             up
             with
             three
             .
             And
             contrariwise
             ,
             make
             the
             Cylinder
             D
             E
             29
             inches
             ,
             that
             's
             now
             but
             28
             ,
             it
             will
             press
             up
             with
             11
             ounce
             only
             .
             (
             VVith
             28
             it
             presseth
             up
             with
             12.
             )
             Make
             it
             30
             inches
             high
             ,
             it
             will
             press
             up
             with
             10.
             
             If
             it
             be
             31
             inches
             ,
             it
             presseth
             up
             with
             nine
             ,
             and
             so
             forward
             .
             Lastly
             ,
             make
             the
             Cylinder
             A
             B
             15
             inches
             ,
             that
             's
             now
             but
             14
             ,
             it
             presseth
             up
             with
             26
             (
             with
             14
             ,
             it
             presseth
             up
             with
             27
             )
             make
             it
             16
             ,
             it
             presseth
             up
             with
             25
             ;
             make
             it
             17
             ,
             it
             presseth
             up
             with
             24.
             
             We
             see
             ninthly
             ,
             that
             in
             Fluids
             ,
             we
             may
             make
             a
             distinction
             between
             a
             sustentation
             ,
             and
             an
             equipondium
             .
             'T
             is
             evident
             here
             ,
             because
             there
             's
             a
             perfect
             equipondium
             between
             the
             42
             inches
             of
             Mercury
             G
             H
             ,
             and
             the
             outward
             Water
             that
             's
             49
             foot
             deep
             .
             But
             't
             is
             not
             so
             ,
             between
             the
             said
             Water
             ,
             and
             the
             Mercury
             D
             E
             ;
             because
             the
             said
             Water
             is
             able
             to
             raise
             the
             said
             Mercury
             14
             inches
             higher
             :
             therefore
             the
             Water
             only
             sustains
             the
             Mercury
             D
             E
             ,
             but
             counterballances
             the
             Mercury
             G
             H.
             We
             see
             tenthly
             ,
             that
             the
             pondus
             of
             the
             pillar
             of
             Water
             B
             C
             is
             counterpoised
             by
             two
             distinct
             powers
             really
             .
             The
             one
             is
             the
             14
             ounce
             of
             Stone
             in
             the
             scale
             L
             ,
             the
             other
             is
             the
             14
             inches
             of
             Mercury
             A
             B
             ,
             that
             as
             really
             thrusts
             up
             the
             Water
             ,
             as
             the
             scale
             K
             pulls
             it
             up
             ,
             by
             vertue
             of
             the
             opposite
             weight
             .
             Eleventhly
             ,
             take
             away
             the
             Stone
             L
             ,
             and
             you
             will
             find
             the
             Pipe
             with
             the
             Mercury
             A
             B
             sink
             down
             :
             this
             happens
             ,
             not
             because
             the
             surface
             of
             Water
             on
             which
             it
             rests
             is
             not
             able
             to
             sustain
             it
             ,
             but
             because
             the
             14
             ounce
             of
             the
             Water
             B
             C
             ,
             that
             was
             supported
             by
             the
             Stone
             ,
             doth
             now
             press
             it
             down
             .
             Twelfthly
             ,
             the
             more
             a
             Body
             is
             unequally
             pressed
             by
             a
             Fluid
             ,
             the
             more
             of
             the
             weight
             of
             that
             Fluid
             is
             sensible
             ;
             and
             the
             
             more
             equally
             a
             Body
             is
             pressed
             ,
             the
             less
             sensible
             is
             the
             weight
             of
             that
             Fluid
             :
             this
             is
             evident
             ,
             because
             there
             's
             a
             greater
             weight
             of
             the
             VVater
             H
             I
             found
             in
             the
             Ballance
             (
             it
             takes
             42
             ounce
             to
             counterpoise
             it
             )
             than
             of
             the
             VVater
             E
             F
             ,
             which
             is
             counterpoised
             with
             28
             ounce
             :
             and
             the
             reason
             is
             ,
             because
             the
             top
             of
             the
             Tub
             H
             ,
             supports
             the
             whole
             39
             ounce
             of
             VVater
             H
             I
             ,
             the
             Mercury
             within
             the
             Tub
             ,
             not
             being
             able
             in
             the
             least
             to
             counterpoise
             it
             ,
             or
             thrust
             it
             up
             .
             But
             because
             the
             Tub
             D
             E
             ,
             is
             more
             equally
             pressed
             (
             the
             VVater
             E
             F
             presseth
             down
             with
             40
             ,
             and
             the
             Mercury
             D
             E
             presseth
             up
             with
             12
             )
             therefore
             less
             weight
             of
             the
             VVater
             E
             F
             burdens
             the
             Ballance
             ,
             only
             28
             ounce
             .
             Hence
             it
             is
             ,
             that
             because
             the
             Tub
             A
             B
             ,
             is
             more
             equally
             pressed
             ,
             than
             either
             D
             E
             or
             G
             H
             ,
             there
             's
             less
             of
             the
             weight
             of
             the
             VVater
             B
             C
             ,
             found
             in
             the
             Ballance
             ,
             only
             14
             ounce
             .
             Thirteenthly
             ,
             if
             in
             the
             instant
             of
             time
             ,
             while
             the
             Tubs
             are
             thus
             suspended
             in
             the
             VVater
             ,
             the
             Pressure
             of
             the
             Air
             above
             were
             taken
             away
             ,
             and
             annihilated
             ;
             then
             first
             ,
             the
             42
             inches
             of
             Mercury
             G
             H
             would
             fall
             down
             ,
             to
             about
             13
             inches
             .
             Secondly
             ,
             the
             28
             inches
             of
             Mercury
             D
             E
             ,
             would
             fall
             down
             to
             as
             many
             .
             And
             lastly
             ,
             the
             14
             A
             B
             ,
             would
             sink
             down
             to
             the
             same
             height
             .
             The
             reason
             is
             ,
             because
             the
             Pressure
             of
             the
             Air
             being
             equivalent
             to
             34
             foot
             of
             VVater
             ,
             no
             more
             would
             remain
             but
             15
             foot
             ,
             which
             is
             the
             real
             height
             ,
             according
             to
             Z
             M.
             But
             15
             foot
             of
             Water
             ,
             cannot
             sustain
             moe
             inches
             of
             Mercury
             than
             about
             13.
             
             And
             consequently
             ,
             first
             ,
             14
             ounce
             of
             Stone
             in
             the
             Ballance
             ,
             would
             counterpoise
             the
             whole
             Water
             B
             C.
             The
             reason
             is
             ,
             because
             the
             Water
             B
             C
             is
             but
             of
             14
             ounce
             ;
             and
             the
             Mercury
             A
             B
             ,
             being
             but
             13
             inches
             high
             ,
             could
             impress
             no
             impulse
             upon
             the
             top
             of
             the
             Tub
             within
             ,
             that
             's
             14
             inches
             high
             .
             Secondly
             ,
             13
             ounce
             of
             Stone
             in
             the
             Scale
             L
             ,
             would
             
             counterpoise
             the
             whole
             Water
             E
             F
             ,
             seing
             E
             F
             is
             but
             13
             ounce
             .
             Thirdly
             ,
             the
             same
             weight
             (
             one
             ounce
             being
             deduced
             )
             would
             counterpoise
             the
             Water
             H
             I
             ,
             because
             in
             this
             case
             ,
             it
             weighs
             but
             12
             ounce
             ,
          
           
             To
             proceed
             a
             little
             further
             ,
             imagine
             the
             Pipe
             G
             H
             to
             be
             suspended
             by
             the
             ballance
             ,
             as
             the
             Pipe
             A
             B
             is
             ;
             and
             then
             a
             little
             hole
             opened
             in
             the
             top
             H
             ,
             to
             suffer
             the
             Water
             to
             come
             in
             ,
             till
             the
             Mercury
             subside
             14
             inches
             ,
             namely
             from
             Q
             to
             O
             (
             imagine
             this
             Tub
             to
             be
             the
             other
             )
             and
             then
             stop
             it
             .
             The
             reason
             why
             the
             VVater
             rusheth
             in
             ,
             and
             presseth
             down
             the
             Mercury
             ,
             is
             the
             force
             and
             Pressure
             of
             it
             :
             for
             the
             said
             VVater
             ,
             finding
             the
             Cylinder
             in
             equilibrio
             with
             the
             outward
             VVater
             ,
             presently
             by
             its
             own
             weight
             ,
             casts
             the
             scales
             ,
             which
             is
             easily
             done
             ,
             seeing
             the
             surface
             G
             S
             M
             supports
             as
             much
             burden
             as
             it
             can
             .
             But
             that
             which
             is
             more
             considerable
             is
             this
             ;
             after
             the
             subsiding
             of
             the
             Mercury
             from
             Q
             to
             O
             ;
             the
             equilibrium
             that
             was
             between
             the
             scale
             of
             the
             ballance
             ,
             and
             the
             VVater
             Q
             R
             is
             destroyed
             :
             for
             whereas
             42
             ounces
             were
             required
             before
             ;
             29
             will
             now
             do
             it
             .
             For
             understanding
             the
             reason
             of
             this
             ,
             consider
             that
             between
             Q
             and
             O
             ,
             are
             14
             inches
             of
             VVater
             rushed
             in
             ,
             which
             are
             equivalent
             to
             one
             inch
             of
             Mercury
             .
             Next
             ,
             according
             to
             former
             reasonings
             ,
             the
             ballance
             must
             support
             29
             ounces
             of
             the
             VVater
             Q
             R
             ;
             because
             in
             this
             case
             ,
             the
             top
             of
             the
             Pipe
             within
             ,
             is
             pressed
             up
             with
             the
             weight
             of
             13
             ounces
             ;
             which
             in
             effect
             ,
             diminisheth
             as
             much
             of
             the
             downward
             Pressure
             of
             the
             VVater
             R
             Q
             ,
             which
             before
             had
             the
             burden
             of
             39
             ounces
             .
             But
             why
             is
             the
             Tub
             prest
             up
             with
             13
             ounces
             ?
             I
             answer
             ,
             because
             the
             Mercury
             ,
             that
             before
             was
             42
             inches
             ,
             is
             now
             but
             28
             ,
             or
             having
             the
             14
             inches
             of
             Water
             Q
             O
             above
             it
             ,
             it
             is
             29
             ,
             therefore
             being
             shorter
             ,
             the
             surface
             G
             S
             M
             is
             the
             more
             able
             to
             Press
             it
             up
             ,
             even
             with
             as
             much
             more
             force
             ,
             as
             it
             is
             in
             inches
             shorter
             .
          
           
           
             In
             the
             second
             place
             ,
             let
             in
             as
             much
             Water
             more
             ,
             as
             will
             depress
             the
             Mercury
             other
             14
             inches
             ,
             namely
             from
             O
             to
             P.
             In
             this
             case
             ,
             16
             ounce
             of
             stone
             will
             make
             an
             equipondium
             ;
             because
             ,
             the
             14
             inches
             of
             Mercury
             P
             S
             ,
             and
             the
             28
             inches
             of
             Water
             P
             O
             Q
             ,
             being
             a
             far
             lighter
             burden
             by
             26
             ,
             than
             the
             42
             inches
             of
             Mercury
             ,
             the
             surface
             G
             S
             M
             must
             be
             far
             abler
             to
             press
             them
             up
             now
             ,
             than
             before
             :
             and
             therefore
             ,
             must
             diminish
             as
             much
             of
             the
             downward
             Pressure
             of
             the
             VVater
             Q
             R
             ,
             that
             burdens
             the
             Ballance
             ,
             as
             themselves
             wants
             of
             weight
             :
             seing
             then
             ,
             the
             whole
             Cylinder
             of
             Mercury
             ,
             and
             Water
             together
             ,
             are
             but
             equivalent
             for
             weight
             to
             16
             inches
             of
             Mercury
             ,
             the
             top
             of
             the
             Tub
             within
             ,
             must
             be
             prest
             up
             with
             26
             ounce
             ;
             and
             therefore
             they
             by
             their
             upward
             Pressure
             ,
             must
             diminish
             26
             ounce
             of
             the
             weight
             of
             the
             Water
             R
             Q
             ,
             that
             weighs
             39.
             
             Lastly
             ,
             let
             in
             so
             much
             VVater
             ,
             as
             will
             depress
             the
             last
             14
             inches
             P
             S
             ;
             and
             you
             will
             find
             no
             more
             weight
             required
             in
             the
             Ballance
             to
             make
             an
             equipondium
             ,
             than
             counterpoiseth
             the
             simple
             weight
             of
             the
             Tub
             ,
             which
             is
             not
             considerable
             .
             The
             reason
             is
             ,
             because
             ,
             the
             part
             S
             ,
             of
             the
             surface
             G
             S
             M
             ,
             being
             liberated
             of
             the
             burden
             of
             Mercury
             ,
             and
             sustaining
             only
             the
             VVater
             within
             the
             Tub
             ,
             in
             stead
             of
             it
             ,
             this
             surface
             presseth
             up
             the
             VVater
             within
             the
             Tub
             ,
             and
             consequently
             the
             top
             of
             it
             ,
             with
             as
             great
             force
             ,
             and
             weight
             ,
             as
             the
             top
             of
             the
             Tub
             without
             is
             depressed
             ,
             with
             the
             outward
             VVater
             R
             Q
             :
             therefore
             ,
             39
             ounce
             depressing
             the
             Tub
             ,
             and
             39
             ounce
             pressing
             it
             up
             ,
             the
             Ballance
             must
             be
             freed
             of
             the
             whole
             weight
             of
             VVater
             R
             Q.
             If
             it
             be
             objected
             ,
             that
             the
             42
             inches
             of
             VVater
             Q
             S
             ,
             are
             equivalent
             in
             weight
             to
             three
             inches
             of
             Mercury
             ;
             therefore
             the
             part
             of
             the
             surface
             S
             ,
             being
             burdened
             with
             this
             ,
             cannot
             press
             up
             ,
             with
             as
             great
             force
             ,
             as
             the
             VVater
             R
             Q
             presseth
             down
             .
             For
             answer
             ,
             consider
             ,
             that
             the
             part
             S
             ,
             is
             able
             to
             
             support
             42
             ounce
             of
             VVater
             ,
             and
             next
             ,
             that
             the
             VVater
             R
             Q
             weighs
             but
             39.
             
             Then
             I
             say
             ,
             seing
             the
             42
             inches
             of
             VVater
             within
             the
             Tub
             ,
             weighs
             only
             three
             ounce
             ,
             the
             part
             S
             ,
             that
             's
             burdened
             therewith
             ,
             being
             able
             to
             support
             42
             ,
             it
             must
             press
             up
             with
             the
             weight
             of
             39
             ,
             and
             so
             counterballance
             the
             VVater
             R
             Q.
             
          
           
             If
             it
             be
             in●uired
             ,
             whether
             or
             not
             ,
             would
             the
             14
             inches
             of
             Mercury
             A
             B
             fall
             down
             ,
             a
             small
             hole
             being
             made
             in
             the
             top
             of
             the
             Tub
             at
             B
             ?
             I
             answer
             ,
             they
             would
             ,
             If
             it
             be
             objected
             ,
             that
             these
             14
             inches
             of
             Mercury
             ,
             are
             not
             in
             equilibri●
             ,
             with
             the
             Pressure
             of
             the
             ambient
             Water
             ,
             as
             the
             Mercury
             G
             H
             ,
             and
             therefore
             they
             cannot
             be
             so
             easily
             depressed
             by
             the
             Water
             ,
             that
             comes
             in
             at
             the
             said
             hole
             .
             I
             answer
             ,
             they
             must
             all
             fall
             down
             ,
             and
             as
             easily
             ,
             as
             the
             other
             ,
             and
             that
             because
             of
             inequality
             of
             weight
             between
             the
             Potentia
             of
             the
             surface
             of
             VVater
             ,
             and
             the
             Pondus
             .
             It
             's
             certain
             ,
             the
             part
             A
             of
             the
             surface
             ,
             cannot
             support
             more
             weight
             of
             any
             kind
             ,
             than
             42
             ounce
             ;
             but
             when
             a
             hole
             is
             opened
             in
             B
             ,
             and
             the
             VVater
             co●es
             in
             ,
             't
             is
             then
             burdened
             with
             the
             weight
             of
             14
             ounce
             of
             Mercury
             ,
             and
             with
             the
             weight
             of
             41
             ounce
             of
             VVater
             ;
             so
             much
             the
             VVater
             B
             C
             weighs
             ,
             which
             is
             55
             ounce
             :
             but
             a
             surface
             that
             hath
             only
             the
             Potentia
             of
             42
             ,
             can
             never
             support
             a
             Pondus
             of
             55
             ,
             no
             not
             of
             43.
             
          
           
             It
             may
             be
             objected
             thus
             :
             Put
             the
             case
             a
             Cylinder
             of
             Gold
             ,
             or
             Brass
             were
             suspended
             in
             this
             VVater
             ;
             as
             the
             Pipe
             and
             Mercury
             G
             H
             are
             suspended
             by
             the
             Ballance
             ,
             would
             not
             the
             Ballance
             support
             the
             whole
             weight
             of
             it
             ,
             without
             supporting
             any
             part
             of
             the
             weight
             of
             the
             VVater
             I
             H
             ,
             that
             rests
             upon
             the
             top
             of
             it
             .
             I
             answer
             ,
             there
             's
             a
             great
             difference
             between
             the
             two
             ;
             because
             a
             Cylinder
             of
             Gold
             or
             Brass
             ,
             suffers
             both
             the
             upward
             and
             downward
             Pressure
             of
             the
             VVater
             ;
             but
             the
             Mercury
             G
             H
             ,
             suffers
             
             only
             the
             upward
             Pressure
             ,
             being
             freed
             of
             the
             downward
             ,
             by
             the
             top
             of
             the
             Tub.
             From
             this
             Experiment
             of
             letting
             in
             the
             VVater
             upon
             the
             top
             of
             the
             Mercury
             ,
             we
             see
             first
             ,
             that
             when
             two
             Fluids
             are
             in
             equilibrio
             one
             with
             another
             ,
             a
             very
             small
             weight
             will
             cast
             and
             turn
             the
             Scales
             ,
             because
             ,
             if
             the
             sixth
             part
             of
             an
             inch
             of
             VVater
             come
             in
             at
             Q
             ,
             it
             presently
             alters
             the
             hight
             of
             the
             Mercury
             from
             42
             inches
             to
             less
             .
             Secondly
             ,
             't
             is
             impossible
             for
             a
             surface
             of
             Water
             ,
             to
             support
             more
             weight
             ,
             than
             its
             own
             proper
             burden
             ;
             because
             the
             part
             S
             ,
             cannot
             support
             more
             ,
             no
             not
             a
             grain
             ,
             than
             42
             ounce
             .
             VVe
             see
             thirdly
             ,
             that
             it
             is
             as
             impossible
             for
             a
             surface
             of
             VVater
             ,
             to
             support
             less
             ,
             than
             its
             own
             burden
             ;
             because
             whatever
             loss
             of
             weight
             the
             Pillar
             of
             Mercury
             S
             Q
             suffers
             ,
             by
             the
             ingress
             of
             the
             VVater
             Q
             O
             ,
             it
             s
             made
             up
             again
             by
             the
             same
             VVater
             .
             If
             it
             be
             objected
             ,
             that
             the
             14
             inches
             of
             VVater
             Q
             O
             ,
             are
             not
             so
             heavy
             by
             far
             ,
             as
             the
             14
             inches
             of
             Mercury
             ,
             that
             fell
             down
             .
             I
             answer
             ,
             its
             true
             ,
             yet
             the
             part
             S
             ,
             is
             as
             much
             burdened
             as
             before
             ,
             because
             what
             is
             wanting
             in
             weight
             ,
             it
             s
             made
             up
             ,
             and
             compensed
             by
             Pressure
             .
             VVe
             see
             fourthly
             ,
             that
             the
             Pressure
             of
             a
             Fluid
             is
             a
             thing
             really
             distinct
             from
             the
             
               natural
               weight
            
             ,
             according
             to
             the
             22
             Theorem
             :
             because
             though
             the
             14
             inches
             of
             Water
             Q
             O
             ,
             are
             not
             so
             heavy
             naturally
             as
             the
             14
             inches
             of
             Mercury
             that
             fell
             down
             ,
             yet
             the
             Pressure
             of
             them
             upon
             the
             surface
             S
             ,
             is
             as
             much
             .
             We
             see
             fifthly
             ,
             that
             14
             inches
             of
             Water
             ,
             that
             's
             ●
             body
             fourteen
             times
             lighter
             than
             Mercury
             ,
             may
             have
             as
             much
             weight
             with
             them
             ,
             as
             14
             ounce
             of
             Mercury
             .
             We
             see
             sixthly
             ,
             that
             a
             Cylinder
             of
             Mercury
             cannot
             be
             suspended
             in
             Air
             ,
             or
             in
             Water
             unless
             it
             be
             guarded
             with
             a
             Tub
             ,
             to
             preserve
             it
             from
             the
             downward
             Pressure
             of
             that
             Air
             or
             Water
             :
             for
             by
             opening
             an
             hole
             in
             Q
             ,
             the
             Me●cury
             subsides
             .
             We
             see
             seventhly
             ,
             that
             't
             is
             impossible
             〈…〉
             Fluids
             to
             suspend
             
             one
             another
             mutually
             ,
             unless
             there
             be
             a
             sort
             of
             equipondium
             between
             them
             ;
             because
             no
             sooner
             you
             destroy
             the
             equipondium
             ,
             between
             the
             42
             inches
             of
             Mercury
             Q
             S
             ,
             and
             the
             part
             of
             the
             surface
             S
             ,
             by
             the
             ingress
             of
             the
             Water
             Q
             O
             ,
             but
             assoon
             there
             ariseth
             a
             new
             one
             .
             We
             see
             eighthly
             (
             as
             we
             noted
             before
             )
             the
             nearer
             a
             Body
             comes
             to
             be
             equally
             pressed
             with
             a
             Fluid
             ,
             the
             less
             is
             the
             Pressure
             of
             that
             Fluid
             sensible
             :
             because
             less
             weight
             is
             required
             in
             the
             Ballance
             ,
             to
             counterpoise
             the
             Pressure
             ,
             and
             weight
             of
             the
             Water
             R
             Q
             ,
             after
             the
             ingress
             of
             the
             Water
             Q
             O
             P
             ,
             than
             after
             the
             ingress
             of
             the
             Water
             Q
             O.
             We
             see
             ninthly
             ,
             that
             when
             a
             Body
             is
             equally
             ,
             and
             uniformly
             pre●●ed
             with
             a
             Fluid
             ,
             the
             Pressure
             is
             insensible
             ;
             because
             ,
             after
             the
             Water
             hath
             thrust
             down
             all
             the
             Mercury
             from
             Q
             to
             S
             ,
             there
             's
             no
             more
             weight
             at
             all
             of
             the
             Water
             R
             Q
             found
             in
             the
             Ballance
             .
             We
             see
             tenthly
             ,
             that
             not
             only
             in
             Water
             ,
             the
             Pressure
             of
             Water
             may
             be
             found
             ,
             but
             out
             of
             it
             ,
             namely
             in
             the
             Air
             ;
             as
             is
             clear
             from
             the
             Ballance
             ,
             that
             supports
             the
             Pressure
             of
             the
             Water
             R
             Q.
             We
             see
             eleventhly
             ,
             a
             ground
             to
             distinguish
             between
             the
             
               natural
               Ballance
            
             ,
             and
             the
             
               artificial
               Ballance
            
             .
             The
             
               artificial
               Ballance
            
             ,
             is
             the
             Ballance
             K
             L
             :
             the
             natural
             ,
             is
             the
             Pipe
             Q
             S.
             We
             see
             twelfthly
             ,
             that
             they
             keep
             a
             correspondence
             between
             themselves
             ,
             or
             some
             Analogy
             :
             for
             by
             what
             proportion
             the
             Water
             thrusts
             down
             the
             Mercury
             ,
             by
             that
             same
             proportion
             the
             pondus
             L
             ,
             of
             the
             Ballance
             is
             lessened
             :
             and
             by
             what
             proportion
             the
             Mercury
             rises
             in
             the
             Pipe
             ,
             by
             that
             same
             ,
             is
             the
             weight
             L
             augmented
             in
             the
             Scale
             .
             We
             may
             subjoyn
             lastly
             ,
             that
             the
             easiest
             way
             of
             explicating
             the
             Phenomena
             of
             Nature
             ,
             is
             not
             always
             the
             best
             ,
             and
             truest
             .
             For
             some
             may
             think
             ,
             it
             were
             far
             easier
             to
             say
             ,
             that
             the
             Ballance
             supports
             the
             Mercury
             A
             B
             ,
             or
             D
             E
             ,
             and
             not
             any
             part
             of
             the
             Water
             B
             C
             ,
             or
             E
             F.
             But
             such
             a
             way
             would
             be
             false
             ,
             and
             absurd
             ,
             and
             contrary
             to
             all
             the
             former
             Doctrine
             .
          
        
         
           
           
             EXPERIMENT
             XII
             .
             Figure
             16.
             
          
           
             THis
             Schematism
             represents
             a
             Water
             100
             foot
             deep
             ,
             whose
             first
             and
             visible
             surface
             is
             I
             H
             K.
             And
             L
             M
             is
             the
             ground
             of
             it
             .
             C
             D
             is
             a
             piece
             of
             brass
             30
             inches
             high
             ,
             and
             12
             inches
             in
             diameter
             ,
             suspended
             upon
             the
             imaginary
             surface
             of
             Water
             A
             N
             B
             ,
             which
             is
             distant
             from
             the
             top
             I
             H
             K
             ,
             25
             foot
             .
             This
             Brass
             cannot
             go
             farder
             down
             ,
             when
             demitted
             from
             H
             ;
             because
             it
             's
             keeped
             up
             ,
             by
             the
             Force
             and
             Pressure
             of
             the
             surface
             of
             Water
             A
             N
             B
             ,
             which
             I
             prove
             thus
             .
             The
             part
             B
             sustains
             
               de
               facto
            
             ,
             a
             Pillar
             of
             Water
             K
             B
             1400
             pound
             weight
             :
             therefore
             the
             part
             N
             is
             able
             to
             sustain
             as
             much
             .
             I
             suppose
             here
             ,
             the
             said
             piece
             of
             Brass
             to
             weigh
             1400
             pound
             .
             The
             Water
             K
             B
             is
             1400
             pound
             ,
             because
             its
             a
             Pillar
             25
             foot
             high
             ,
             and
             12
             inches
             thick
             ,
             for
             one
             cubical
             foot
             weighs
             56
             pound
             Trois
             .
             The
             connexion
             of
             the
             argument
             is
             evident
             ,
             because
             it
             is
             as
             easie
             for
             a
             surface
             of
             Water
             ,
             to
             sustain
             a
             solid
             Body
             ,
             as
             to
             sustain
             a
             Fluid
             Body
             :
             therefore
             ,
             if
             the
             part
             B
             ,
             support
             the
             Fluid
             Pillar
             K
             B
             ,
             the
             part
             N
             must
             be
             able
             to
             support
             likewise
             the
             solid
             Pillar
             C
             D
             ,
             which
             is
             of
             the
             same
             weight
             .
             I●
             it
             be
             objected
             ,
             that
             the
             part
             N
             ,
             sustains
             besides
             the
             Brass
             C
             D
             ,
             a
             Pillar
             of
             Water
             E
             F
             22
             foot
             high
             ,
             and
             a
             half
             ,
             which
             two
             will
             weigh
             2260
             pound
             .
             I
             answer
             ,
             upon
             supposition
             ,
             that
             neither
             Water
             nor
             Air
             succeeded
             ,
             the
             space
             E
             F
             being
             void
             of
             both
             ,
             the
             Brass
             would
             be
             suspended
             with
             the
             force
             and
             power
             of
             the
             Water
             N.
             And
             though
             this
             cannot
             be
             made
             practicable
             ,
             yet
             the
             Theory
             of
             it
             may
             conduce
             much
             for
             explicating
             the
             secrets
             and
             mysteries
             of
             the
             Hydrostaticks
             .
             But
             why
             ought
             the
             Brass
             to
             be
             suspended
             
             at
             25
             foot
             from
             the
             top
             ?
             I
             answer
             ,
             because
             the
             potentia
             of
             the
             surface
             A
             N
             B
             ,
             is
             equal
             to
             the
             pondus
             of
             the
             Brass
             .
             To
             evidence
             this
             ,
             consider
             that
             Brass
             is
             a
             Body
             naturally
             heavier
             then
             Water
             ,
             I
             shall
             suppose
             ten
             times
             ,
             that
             's
             to
             say
             ,
             one
             inch
             of
             Brass
             will
             counterpoise
             ten
             inches
             of
             Water
             .
             If
             this
             inequality
             be
             ,
             then
             must
             this
             Pillar
             of
             Brass
             go
             so
             much
             farder
             down
             ,
             than
             the
             first
             surface
             I
             H
             K
             ,
             as
             the
             one
             is
             heavier
             
               in
               specie
            
             ,
             or
             naturally
             ,
             than
             the
             other
             :
             therefore
             it
             must
             sink
             25
             foot
             exactly
             ;
             seing
             a
             piece
             of
             Brass
             30
             inches
             high
             ,
             requires
             400
             inches
             of
             Water
             ,
             or
             25
             foot
             to
             counterpoise
             it
             :
             for
             if
             one
             inch
             of
             Brass
             require
             ten
             inches
             of
             Water
             ,
             then
             surely
             30
             inches
             must
             require
             300.
             
             Yet
             it
             is
             no
             matter
             ,
             what
             the
             thickness
             be
             ,
             provided
             it
             be
             no
             higher
             than
             30
             inches
             .
          
           
             To
             advance
             some
             farder
             ,
             let
             us
             make
             a
             second
             supposition
             ,
             namely
             ,
             while
             the
             Brass
             is
             thus
             suspended
             upon
             the
             surface
             A
             N
             B
             ,
             suppose
             the
             Air
             to
             come
             down
             ,
             and
             fill
             up
             the
             imaginary
             space
             E
             F
             ,
             then
             must
             the
             Brass
             be
             thrust
             down
             as
             far
             as
             the
             surface
             O
             P
             ,
             that
             's
             34
             foot
             below
             the
             surface
             A
             N
             D
             ,
             and
             59
             from
             the
             top
             .
             The
             reason
             of
             it
             is
             this
             ,
             because
             the
             weight
             of
             the
             Air
             superadded
             ,
             is
             equivalent
             to
             the
             Pressure
             of
             a
             Pillar
             of
             Mercury
             29
             inches
             high
             ,
             and
             12
             inches
             thick
             :
             therefore
             the
             Brass
             being
             burdened
             with
             this
             ,
             it
             must
             go
             so
             farder
             down
             ,
             till
             it
             meet
             with
             a
             surface
             ,
             whose
             potentia
             is
             equal
             in
             weight
             ,
             to
             the
             pondus
             of
             both
             ,
             which
             is
             precisely
             59
             foot
             from
             the
             top
             :
             for
             if
             one
             inch
             of
             Mercury
             require
             14
             of
             Water
             ,
             then
             29
             inches
             must
             require
             405
             inches
             ,
             or
             34
             foot
             .
             In
             a
             word
             ,
             it
             must
             go
             as
             far
             down
             ,
             as
             that
             surface
             ,
             that
             sustains
             a
             Pillar
             of
             Water
             ,
             that
             would
             counterpoise
             in
             a
             Ballance
             ,
             the
             Brass
             C
             D
             ,
             and
             a
             Pillar
             of
             Mercury
             29
             inches
             high
             ,
             and
             12
             inches
             thick
             ,
             both
             which
             weighs
             3290
             pound
             .
          
           
           
             From
             what
             is
             said
             ,
             we
             see
             first
             ,
             that
             of
             two
             heavy
             bodies
             differing
             in
             weight
             ,
             the
             lighter
             may
             go
             further
             down
             than
             the
             heavier
             .
             This
             is
             clear
             ,
             because
             a
             slender
             Cylinder
             of
             Gold
             ,
             in
             form
             of
             an
             Arrow
             ,
             half
             an
             inch
             thick
             ,
             and
             28
             inches
             long
             ,
             weighing
             28
             pound
             (
             't
             is
             no
             matter
             ,
             though
             the
             just
             weight
             of
             it
             be
             not
             determined
             )
             will
             go
             down
             35
             foot
             in
             Water
             ,
             before
             it
             meet
             with
             a
             surface
             ,
             whose
             potentia
             is
             equal
             in
             weight
             to
             its
             own
             pondus
             ;
             for
             if
             Gold
             be
             15
             times
             heavier
             naturally
             than
             Water
             ,
             then
             the
             said
             Cylinder
             must
             go
             down
             before
             it
             rest
             ,
             420
             inches
             ,
             or
             35
             foot
             .
             But
             a
             piece
             of
             Gold
             12
             inches
             long
             ,
             and
             six
             inches
             thick
             ,
             that
             perhaps
             will
             weigh
             208
             pound
             ,
             will
             sink
             no
             further
             than
             15
             foot
             .
             And
             the
             reason
             is
             ,
             because
             ,
             if
             one
             inch
             of
             Gold
             require
             15
             of
             VVater
             to
             counterpoise
             it
             ,
             then
             12
             must
             only
             require
             180
             ,
             or
             15
             foot
             .
             Note
             ,
             that
             both
             the
             bodies
             must
             go
             down
             Perpendicularly
             ,
             and
             not
             as
             it
             were
             Horizontally
             ,
             with
             their
             sides
             downmost
             :
             for
             if
             they
             go
             down
             after
             this
             manner
             ,
             they
             cannot
             sink
             so
             far
             .
             The
             reason
             of
             this
             is
             also
             evident
             ,
             because
             a
             heavy
             body
             goes
             so
             far
             down
             ,
             and
             no
             further
             ,
             till
             it
             hath
             thrust
             ●s
             much
             Water
             out
             of
             its
             place
             ,
             as
             will
             counterpoise
             it self
             in
             a
             Ballance
             .
             That
             's
             to
             say
             ,
             if
             an
             heavy
             body
             weigh
             100
             pound
             ,
             it
             must
             go
             no
             further
             down
             ,
             than
             after
             it
             hath
             thrust
             out
             100
             pound
             of
             Water
             .
             But
             so
             it
             is
             ,
             that
             a
             piece
             of
             Gold
             ,
             in
             form
             of
             an
             Arrow
             ,
             going
             down
             side-wise
             ,
             or
             with
             the
             two
             ends
             parallel
             to
             the
             Horizon
             ,
             will
             thrust
             as
             much
             Water
             out
             of
             its
             place
             ,
             as
             will
             be
             the
             weight
             of
             it self
             ,
             before
             it
             can
             go
             down
             15
             or
             16
             inches
             from
             the
             top
             :
             because
             for
             every
             inch
             it
             goes
             down
             side-wise
             ,
             it
             expell●
             28
             inches
             of
             Water
             .
             In
             going
             down
             two
             inches
             ,
             it
             expells
             56.
             
             In
             going
             down
             three
             inches
             ,
             it
             expells
             84
             ,
             and
             so
             forward
             ,
             till
             it
             go
             down
             15
             inches
             ,
             where
             it
             expells
             420
             inches
             :
             
             but
             420
             inches
             amounts
             to
             35
             foot
             .
             Now
             ,
             take
             a
             Cylinder
             of
             Water
             35
             foot
             high
             ,
             and
             just
             the
             thickness
             of
             the
             Cylinder
             of
             Gold
             ,
             which
             I
             supposed
             to
             be
             of
             half
             an
             inch
             ,
             and
             put
             them
             in
             a
             ballance
             ,
             and
             you
             will
             find
             the
             one
             just
             the
             weight
             of
             the
             other
             .
             Neither
             can
             the
             piece
             of
             Gold
             go
             so
             far
             down
             as
             before
             ,
             if
             it
             go
             down
             side-wise
             ;
             because
             for
             every
             six
             inches
             it
             is
             drowned
             ,
             it
             expells
             a
             bulk
             of
             Water
             12
             inches
             long
             ,
             and
             six
             inches
             thick
             ;
             therefore
             it
             must
             be
             suspended
             ,
             before
             it
             go
             beyond
             90
             inches
             ,
             or
             seven
             foot
             and
             an
             half
             :
             now
             ,
             if
             six
             inches
             give
             one
             foot
             ,
             90
             inches
             will
             give
             15
             foot
             :
             but
             15
             of
             Water
             in
             hight
             ,
             and
             six
             inches
             thick
             ,
             is
             the
             just
             weight
             of
             it
             in
             a
             ballance
             ,
             viz.
             208
             pound
             .
             We
             see
             secondly
             ,
             the
             broader
             and
             larger
             the
             surface
             of
             a
             Fluid
             be
             ,
             't
             is
             the
             more
             able
             and
             strong
             to
             support
             an
             heavy
             burden
             :
             therefore
             the
             part
             of
             a
             surface
             of
             Water
             six
             inches
             square
             every
             way
             ,
             will
             carry
             a
             far
             greater
             weight
             ,
             than
             a
             part
             four
             inches
             square
             .
             Though
             a
             surface
             of
             Water
             34
             or
             35
             foot
             deep
             ,
             be
             not
             able
             to
             sustain
             a
             Cylinder
             of
             Gold.
             if
             it
             exceed
             28
             or
             29
             inches
             in
             hight
             ,
             yet
             take
             a
             Cylinder
             of
             Gold
             ,
             10
             foot
             high
             ,
             and
             reduce
             it
             ,
             by
             making
             it
             thicker
             ,
             to
             the
             hight
             of
             20
             inches
             ,
             a
             surface
             of
             Water
             little
             more
             than
             24
             foot
             deep
             will
             sustain
             it
             .
             Or
             reduce
             a
             Cylinder
             10
             foot
             high
             ,
             which
             requires
             a
             surface
             more
             than
             100
             foot
             deep
             ,
             to
             a
             Cylinder
             six
             inches
             high
             ,
             a
             surface
             little
             more
             than
             seven
             foot
             deep
             will
             support
             it
             .
             We
             see
             thirdly
             ,
             the
             reason
             why
             bodies
             that
             are
             broad
             and
             large
             ,
             move
             ●lowlier
             through
             Air
             and
             VVater
             ,
             than
             bodies
             that
             are
             more
             thin
             ,
             and
             slender
             ,
             though
             both
             be
             of
             the
             same
             weight
             in
             a
             ballance
             .
             For
             example
             ,
             20
             pound
             of
             Lead
             ,
             long
             and
             slender
             like
             an
             Arrow
             ,
             will
             go
             sooner
             to
             the
             ground
             of
             a
             deep
             VVater
             ,
             than
             a
             piece
             of
             Lead
             of
             the
             same
             weight
             ,
             in
             form
             of
             a
             Platter
             or
             Bason
             .
             The
             reason
             is
             ,
             because
             as
             the
             body
             
             is
             broader
             ,
             so
             it
             takes
             a
             broader
             part
             of
             a
             surface
             ,
             which
             broader
             part
             is
             stronger
             and
             abler
             ,
             than
             a
             narrower
             part
             ,
             and
             so
             makes
             the
             greater
             resistance
             .
             The
             same
             is
             the
             reason
             ,
             why
             a
             Bullet
             six
             inches
             in
             Diameter
             ,
             moves
             ●lowlier
             thorow
             the
             Air
             ,
             shot
             from
             a
             Cannon
             ,
             than
             a
             Bullet
             one
             inch
             in
             Diameter
             .
             For
             the
             same
             reason
             ,
             Ships
             of
             seven
             or
             eight
             hundred
             Tun
             ,
             move
             far
             slowlier
             thorow
             the
             Air
             ,
             and
             Water
             ,
             than
             Vessels
             of
             less
             burden
             .
             Item
             ,
             large
             and
             big
             Fowls
             ,
             as
             Eagles
             ,
             move
             slowlier
             ,
             than
             small
             Birds
             ,
             as
             Swallows
             .
             Yea
             ,
             of
             Fowls
             of
             the
             same
             quantity
             ,
             one
             may
             move
             quicklier
             than
             another
             ,
             as
             is
             evident
             in
             long-wing'd
             Hawks
             ,
             as
             Falcons
             ,
             that
             by
             the
             sharpness
             of
             their
             Wings
             ,
             move
             far
             more
             space
             in
             half
             an
             hour
             ,
             than
             Kites
             ,
             or
             Gose-Hawks
             ,
             whose
             wings
             are
             rounder
             .
             We
             see
             fourthly
             ,
             that
             there
             's
             no
             body
             how
             heavy
             soever
             ,
             but
             it
             may
             be
             supported
             by
             the
             surface
             of
             a
             Fluid
             ,
             either
             in
             Air
             or
             in
             VVater
             .
             I
             grant
             ,
             the
             strongest
             surface
             of
             Air
             ,
             that
             can
             be
             had
             ,
             is
             not
             able
             to
             support
             more
             weight
             ,
             than
             a
             Cylinder
             of
             Gold
             28
             inches
             high
             :
             yet
             though
             it
             were
             as
             large
             ,
             and
             broad
             ,
             as
             a
             Mill-stone
             ,
             if
             it
             do
             not
             exceed
             the
             said
             hight
             ,
             the
             Air
             is
             able
             to
             sustain
             it
             .
             For
             the
             same
             cause
             ,
             if
             it
             were
             possible
             to
             free
             a
             Mill-stone
             of
             the
             Air
             ,
             that
             rests
             upon
             it
             ,
             the
             Air
             below
             would
             lift
             it
             from
             the
             ground
             ,
             and
             carry
             it
             up
             many
             fathoms
             ,
             even
             till
             it
             came
             to
             a
             surface
             ,
             equal
             in
             power
             to
             the
             weight
             of
             the
             Stone
             .
             Or
             ,
             if
             a
             large
             Mill-stone
             were
             demitted
             from
             the
             top
             of
             the
             Atmosphere
             ,
             towards
             the
             Earth
             ,
             it
             could
             hardly
             touch
             the
             ground
             ,
             being
             detained
             by
             the
             way
             ,
             by
             a
             surface
             counterpoising
             it
             .
             Or
             if
             it
             did
             touch
             ,
             through
             the
             swiftness
             of
             the
             motion
             ,
             it
             would
             surely
             ▪
             as
             it
             were
             ,
             ●rebound
             ,
             and
             be
             carried
             up
             again
             .
             It
             is
             alwayes
             to
             be
             remembred
             ,
             that
             in
             such
             trials
             ,
             the
             Air
             is
             supposed
             not
             to
             follow
             ,
             or
             to
             be
             united
             ,
             after
             the
             Stone
             
             passeth
             thorow
             .
             Now
             if
             the
             Air
             be
             able
             to
             do
             this
             ,
             far
             more
             the
             VVater
             ,
             that
             's
             a
             body
             a
             thousand
             times
             heavier
             .
             We
             see
             fifthly
             the
             reason
             ,
             why
             heavy
             bodies
             move
             so
             easily
             thorow
             Air
             ,
             and
             Water
             ,
             namely
             because
             the
             parts
             that
             were
             divided
             ,
             by
             the
             body
             that
             is
             moved
             ,
             are
             presently
             reunited
             ,
             and
             closed
             again
             ,
             by
             which
             means
             it
             is
             driven
             forward
             ,
             the
             Pressure
             upon
             the
             back
             ,
             being
             as
             much
             as
             the
             Pressure
             before
             .
             If
             this
             were
             not
             ,
             no
             body
             whatsoever
             would
             be
             able
             to
             move
             it self
             one
             foot
             forward
             .
             For
             example
             ,
             if
             ,
             when
             a
             man
             hath
             advanced
             one
             step
             forward
             ,
             the
             Air
             did
             not
             close
             again
             upon
             his
             back
             ,
             the
             force
             of
             the
             Air
             upon
             his
             belly
             and
             breast
             ,
             would
             not
             only
             stop
             him
             ,
             but
             violently
             thrust
             him
             backward
             .
             We
             see
             sixthly
             ,
             the
             reason
             ,
             why
             the
             same
             body
             descends
             with
             more
             difficulty
             thorow
             Water
             ,
             than
             Air
             ,
             because
             a
             surface
             of
             Water
             is
             far
             stronger
             ,
             than
             a
             surface
             of
             Air.
             We
             see
             seventhly
             ,
             that
             a
             heavy
             body
             is
             never
             suspended
             by
             a
             surface
             of
             Water
             ,
             or
             Air
             ,
             in
             going
             down
             ,
             till
             once
             it
             hath
             displaced
             ,
             as
             much
             Water
             or
             Air
             ,
             as
             will
             counterpoise
             it self
             in
             a
             ballance
             .
             This
             is
             clear
             from
             the
             Brass
             C
             D
             ,
             that
             goes
             alwayes
             down
             ,
             till
             it
             expell
             its
             own
             weight
             of
             Water
             .
             For
             this
             cause
             ,
             if
             a
             Mill-stone
             were
             demitted
             ,
             or
             sent
             down
             from
             the
             top
             of
             the
             Air
             ,
             and
             never
             rested
             ,
             till
             it
             came
             within
             40
             fathom
             of
             the
             Earth
             ,
             then
             so
             much
             Air
             ,
             as
             is
             expelled
             by
             the
             descent
             ,
             is
             the
             just
             weight
             of
             the
             stone
             .
             We
             see
             eighthly
             ,
             the
             heavier
             a
             body
             be
             naturally
             ,
             than
             Water
             ,
             it
             goes
             the
             further
             down
             ,
             and
             the
             lighter
             it
             is
             ,
             it
             sinks
             the
             less
             .
             For
             if
             C
             D
             were
             of
             Gold
             ,
             it
             would
             go
             further
             down
             ,
             than
             being
             of
             Brass
             or
             Iron
             :
             and
             if
             C
             D
             were
             a
             stone
             ,
             that
             's
             lighter
             
               in
               specie
            
             than
             Brass
             ,
             it
             would
             not
             go
             so
             far
             down
             .
             This
             lets
             us
             know
             the
             reason
             ,
             why
             thicker
             ,
             blacker
             ,
             and
             heavier
             clouds
             comes
             nearer
             to
             the
             Earth
             ,
             
             than
             thinner
             ,
             whiter
             ,
             and
             lighter
             .
             VVe
             see
             ninthly
             ,
             that
             the
             Pressure
             of
             the
             Air
             is
             determinable
             ,
             even
             in
             its
             heighest
             degree
             ,
             and
             seemes
             to
             be
             the
             same
             in
             all
             places
             of
             the
             world
             ;
             but
             the
             Pressure
             of
             the
             Water
             is
             not
             so
             .
             The
             reason
             of
             the
             first
             part
             is
             ,
             because
             the
             Element
             of
             Air
             seems
             to
             be
             of
             the
             same
             hight
             in
             all
             places
             ,
             and
             therefore
             we
             may
             know
             its
             outmost
             Pressure
             ,
             which
             is
             just
             equivalent
             to
             the
             weight
             of
             28
             or
             29
             inches
             of
             Gold
             ,
             or
             Mercury
             .
             But
             because
             the
             deepness
             of
             the
             Sea
             is
             variable
             ,
             therefore
             the
             Pressure
             is
             variable
             likewise
             .
             Yet
             if
             the
             exact
             deepness
             ,
             of
             the
             deepest
             place
             were
             known
             ,
             it
             were
             as
             easie
             to
             determine
             the
             greatest
             Pressure
             of
             it
             ,
             as
             to
             determine
             the
             greatest
             Pressure
             of
             the
             Air.
             We
             see
             tenthly
             ,
             that
             a
             very
             small
             weight
             added
             or
             subtracted
             in
             height
             ,
             will
             change
             and
             alter
             the
             counterpoise
             of
             a
             Fluid
             .
             Because
             if
             you
             lay
             but
             one
             ounce
             upon
             the
             top
             of
             the
             brass
             at
             F
             ,
             it
             presently
             subsides
             accordingly
             :
             or
             take
             one
             ounce
             from
             it
             ,
             and
             it
             rises
             .
             But
             though
             never
             so
             much
             weight
             be
             added
             to
             it
             ,
             or
             subtracted
             from
             it
             in
             thickness
             ,
             no
             alteration
             follows
             .
             Therefore
             ,
             though
             this
             piece
             of
             Brass
             C
             D
             ,
             that
             's
             now
             but
             12
             inches
             in
             thickness
             ,
             were
             made
             24
             ,
             by
             which
             means
             the
             weight
             would
             be
             tripled
             and
             more
             ,
             yet
             the
             same
             surface
             A
             N
             B
             would
             sustain
             it
             :
             yet
             ,
             add
             to
             it
             in
             altitude
             ,
             but
             one
             inch
             ,
             and
             presently
             it
             sinks
             down
             proportionably
             .
             This
             evidently
             discovers
             the
             reason
             ,
             why
             it
             s
             as
             easie
             for
             the
             Air
             ,
             to
             support
             a
             Cylinder
             of
             Mercury
             3
             inches
             thick
             ,
             as
             to
             support
             a
             Cylinder
             half
             an
             inch
             thick
             :
             and
             why
             it
             cannot
             support
             more
             in
             height
             than
             29
             inches
             ,
             and
             why
             it
             cannot
             support
             less
             .
             Now
             the
             reason
             ,
             why
             a
             thicker
             Pillar
             ,
             is
             as
             ●asily
             suspended
             ,
             as
             a
             thinner
             ,
             is
             this
             ,
             because
             if
             a
             Pillar
             of
             Mercury
             be
             thicker
             ,
             and
             consequently
             heavier
             ,
             than
             it
             takes
             a
             broader
             ,
             and
             consequently
             a
             stronger
             surface
             of
             Air
             to
             rest
             
             upon
             :
             if
             it
             be
             but
             slender
             ,
             and
             so
             but
             light
             ,
             then
             it
             takes
             a
             lesser
             part
             of
             a
             surface
             to
             bear
             it
             up
             ,
             and
             consequently
             a
             weaker
             ;
             by
             which
             means
             the
             Pondus
             of
             the
             one
             ,
             is
             alwayes
             proportionable
             to
             the
             Potentia
             of
             the
             other
             .
             Is
             it
             not
             as
             easie
             for
             a
             Pillar
             of
             stone
             ,
             6
             foot
             in
             Diameter
             ,
             to
             support
             another
             six
             foot
             in
             Diameter
             ;
             as
             it
             is
             for
             a
             Pillar
             one
             foot
             in
             Diameter
             ,
             to
             support
             a
             Pillar
             one
             foot
             in
             Diameter
             ?
             But
             as
             a
             Pillar
             one
             foot
             in
             Diameter
             ,
             cannot
             support
             a
             Pillar
             6
             foot
             in
             Diameter
             ,
             neither
             can
             a
             surface
             of
             Air
             ,
             one
             inch
             in
             Diameter
             ,
             support
             a
             Pillar
             of
             Mercury
             6
             inches
             in
             Diameter
             .
             But
             why
             should
             a
             larger
             part
             of
             a
             surface
             be
             stronger
             than
             a
             narrower
             part
             ?
             I
             answer
             ,
             the
             one
             is
             stronger
             than
             the
             other
             ,
             for
             that
             same
             reason
             ,
             why
             a
             thicker
             Cylinder
             is
             heavier
             than
             a
             thinner
             :
             for
             what
             I
             call
             strength
             in
             a
             surface
             ,
             it
             s
             nothing
             else
             but
             weight
             ,
             and
             what
             I
             call
             weight
             in
             a
             Cylinder
             ,
             it
             s
             nothing
             else
             but
             strength
             .
             The
             same
             thing
             hath
             two
             names
             ;
             because
             the
             pillar
             of
             a
             Fluid
             presseth
             down
             ,
             and
             the
             surface
             supports
             :
             therefore
             ,
             in
             the
             one
             it
             s
             called
             pondus
             ,
             in
             the
             other
             potentia
             .
             As
             when
             two
             scales
             are
             in
             equilibrio
             ,
             either
             this
             ,
             or
             that
             may
             be
             called
             the
             pondus
             ;
             or
             either
             this
             ,
             or
             that
             ,
             may
             be
             called
             the
             potentia
             .
             Now
             I
             say
             ,
             if
             a
             part
             of
             a
             surface
             four
             inches
             broad
             ,
             have
             as
             much
             weight
             or
             force
             in
             it
             ,
             as
             a
             Pillar
             of
             Mercury
             four
             inches
             thick
             ;
             then
             surely
             ,
             a
             part
             of
             a
             surface
             eight
             inches
             broad
             ,
             must
             have
             as
             much
             weight
             and
             force
             in
             it
             ,
             as
             a
             Pillar
             of
             Mercury
             eight
             inches
             thick
             .
             But
             why
             ought
             a
             surface
             to
             succumb
             ,
             when
             the
             Pillar
             grows
             in
             hight
             ,
             and
             not
             to
             fail
             when
             it
             grows
             only
             in
             breadth
             ?
             Ans.
             VVhen
             it
             grows
             in
             breadth
             ,
             the
             pondus
             never
             exceeds
             the
             potentia
             ;
             but
             when
             it
             becomes
             higher
             ,
             then
             it
             becomes
             heavier
             .
             That
             's
             to
             say
             ,
             when
             a
             Pillar
             grows
             broader
             ,
             there
             's
             not
             one
             part
             of
             ●he
             surface
             that
             sustains
             it
             ,
             more
             burdened
             than
             another
             ;
             
             seing
             the
             part
             eight
             inches
             broad
             ,
             is
             no
             more
             prest
             with
             a
             Pillar
             eight
             inches
             thick
             ;
             than
             the
             part
             four
             inches
             broad
             ,
             is
             prest
             with
             a
             Pillar
             four
             inches
             thick
             :
             as
             eight
             ounce
             of
             Lead
             in
             this
             Scale
             ,
             is
             no
             more
             counterpoised
             with
             eight
             ounce
             in
             the
             other
             Scale
             ,
             than
             four
             ounce
             in
             this
             Scale
             ,
             is
             counterpoised
             with
             four
             in
             the
             other
             .
             But
             when
             a
             Cylinder
             grows
             in
             hight
             ,
             the
             pondus
             exceeds
             the
             potentia
             ;
             one
             part
             of
             a
             surface
             being
             more
             burdened
             than
             another
             .
             We
             see
             eleventhly
             ,
             that
             in
             a
             large
             surface
             of
             a
             Fluid
             ,
             wherein
             are
             many
             parts
             ;
             each
             part
             is
             able
             to
             sustain
             its
             own
             proper
             burden
             .
             So
             a
             part
             eight
             inches
             in
             Diameter
             supports
             a
             Pillar
             eight
             inches
             thick
             ;
             and
             a
             part
             four
             inches
             ,
             supports
             a
             Cylinder
             four
             inches
             thick
             ;
             but
             cannot
             support
             a
             Pillar
             six
             inches
             thick
             .
             But
             this
             seems
             rather
             to
             flow
             from
             the
             disproportion
             of
             Magnitudes
             ,
             seing
             a
             circular
             plain
             4
             inches
             in
             diameter
             ,
             cannot
             receive
             a
             Base
             of
             a
             Pillar
             6
             inches
             in
             diameter
             .
             But
             this
             is
             certain
             from
             the
             very
             nature
             of
             Fluids
             ,
             that
             in
             a
             deep
             VVater
             ,
             wherein
             may
             be
             distinguished
             100
             ,
             or
             1000
             different
             surfaces
             ,
             each
             one
             is
             able
             to
             support
             his
             own
             burden
             ,
             and
             no
             more
             .
          
        
         
           
             EXPERIMENT
             XIII
             .
             Figure
             17
             ,
             18
             ,
             19.
             
          
           
             FOr
             making
             this
             Experiment
             ,
             take
             two
             plain
             Bodies
             of
             Brass
             ,
             or
             Marble
             well
             polished
             .
             Make
             them
             of
             any
             quantity
             ;
             but
             for
             this
             present
             use
             ,
             let
             each
             of
             them
             be
             four
             inches
             broad
             square-wise
             .
             Upon
             the
             back
             part
             ,
             let
             each
             one
             have
             an
             handle
             about
             six
             inches
             long
             ,
             of
             the
             same
             metal
             ,
             formed
             with
             the
             plain
             it self
             ,
             in
             the
             founding
             (
             if
             they
             be
             of
             Brass
             )
             as
             is
             represented
             in
             this
             Schematism
             .
             When
             
             they
             are
             thus
             prepared
             ,
             anoint
             their
             inner-sides
             with
             Oyl
             or
             Water
             ,
             and
             having
             thrust
             the
             one
             face
             alongst
             upon
             the
             other
             ,
             with
             all
             the
             strength
             you
             have
             ,
             till
             all
             the
             four
             edges
             agree
             ,
             two
             whereof
             are
             represented
             by
             A
             B
             ,
             and
             C
             D
             ,
             you
             will
             find
             them
             cleave
             so
             closs
             together
             ,
             as
             if
             they
             were
             but
             one
             Body
             .
             The
             effect
             is
             this
             ,
             that
             ordinary
             strength
             will
             not
             pull
             them
             asunder
             ;
             and
             that
             under
             a
             surface
             of
             Water
             ,
             a
             stronger
             pull
             is
             required
             than
             in
             the
             Air.
             
          
           
             That
             we
             may
             deduce
             some
             Hydrostatical
             conclusions
             from
             this
             Experiment
             ,
             let
             us
             suppose
             these
             two
             plain
             Bodies
             to
             be
             united
             in
             the
             middle
             of
             the
             VVater
             I
             K
             P
             Q
             ,
             that
             's
             34
             foot
             deep
             ,
             and
             suspended
             by
             a
             beam
             or
             long
             tree
             T
             V
             existing
             in
             the
             Air
             ,
             near
             the
             top
             of
             the
             VVater
             ,
             by
             a
             chord
             S
             E
             passing
             between
             the
             middle
             of
             the
             beam
             ,
             and
             the
             end
             of
             the
             handle
             at
             E.
             Suppose
             next
             a
             great
             weight
             of
             Lead
             R
             ,
             350
             pound
             ,
             to
             be
             appended
             to
             the
             end
             of
             the
             handle
             at
             H
             ,
             of
             the
             under
             plain
             Body
             C
             D
             N
             O.
             This
             done
             ,
             I
             affirm
             ,
             that
             the
             beam
             T
             V
             ,
             neither
             sustains
             the
             under
             plain
             Body
             C
             D
             N
             O
             G
             H
             ,
             not
             the
             350
             pound
             weight
             of
             Lead
             R
             ,
             that
             hangs
             down
             from
             the
             handle
             G
             H.
             If
             it
             be
             objected
             ,
             that
             the
             beam
             supports
             the
             upper
             plain
             Body
             A
             B
             L
             M
             F
             E
             ;
             therefore
             it
             must
             bear
             the
             weight
             also
             of
             the
             under
             plain
             C
             D
             N
             O
             G
             H
             ,
             with
             the
             weight
             R
             ;
             seing
             they
             are
             both
             united
             together
             ,
             and
             cleave
             so
             closs
             ,
             as
             if
             they
             were
             but
             one
             Body
             .
             I
             answer
             ,
             it
             supports
             the
             one
             unquestionably
             ,
             but
             not
             the
             other
             .
             To
             explicate
             this
             Hydrostatical
             Mystery
             ,
             I
             must
             aver
             three
             things
             ;
             first
             ,
             that
             the
             inferior
             plain
             is
             supported
             by
             the
             upward
             Pressure
             〈◊〉
             the
             lower
             VVater
             P
             Q
             N
             O.
             Secondly
             ,
             that
             the
             burden
             which
             the
             beam
             sustains
             ,
             is
             not
             the
             weight
             of
             the
             under
             plain
             ,
             but
             the
             weight
             of
             the
             34
             foot
             of
             Water
             I
             K
             L
             M.
             Thirdly
             ,
             that
             this
             weight
             is
             exactly
             the
             weight
             
             of
             the
             inferior
             plain
             ,
             and
             Lead
             R.
             But
             is
             it
             not
             more
             easie
             to
             say
             ,
             that
             the
             beam
             supports
             both
             the
             plains
             ?
             I
             answer
             ,
             if
             I
             say
             so
             ,
             I
             can
             neither
             affirm
             truth
             ,
             nor
             speak
             consequentially
             ,
             But
             may
             it
             not
             be
             said
             ,
             that
             the
             inferior
             plain
             is
             supported
             both
             by
             the
             beam
             ,
             and
             the
             lower
             water
             P
             Q
             N
             O?
             I
             answer
             ,
             this
             is
             impossible
             ;
             because
             one
             and
             the
             same
             weight
             ,
             cannot
             be
             supported
             totally
             ,
             by
             two
             distinct
             supporters
             .
          
           
             For
             making
             these
             assertions
             evident
             ,
             I
             must
             suppose
             the
             superior
             Water
             I
             K
             L
             M
             to
             be
             34
             foot
             deep
             ,
             and
             to
             weigh
             ,
             if
             it
             were
             put
             into
             a
             ballance
             ,
             400
             pound
             :
             and
             which
             is
             unquestionable
             ,
             that
             the
             said
             Water
             rests
             upon
             the
             back
             of
             the
             superior
             plain
             L
             M.
             I
             suppose
             secondly
             ,
             that
             the
             lower
             Water
             P
             Q
             N
             O
             weighs
             as
             much
             ,
             and
             thrusts
             up
             the
             inferior
             plain
             with
             as
             great
             weight
             ,
             as
             the
             superior
             plain
             is
             prest
             down
             with
             ,
             by
             the
             superior
             Water
             .
             This
             is
             evident
             from
             former
             Experiments
             .
             And
             lastly
             ,
             I
             suppose
             each
             plain
             to
             weigh
             two
             pound
             ,
             and
             the
             weight
             of
             Lead
             R
             350.
             
             It
             is
             to
             be
             observed
             here
             ,
             that
             no
             mistake
             may
             arise
             in
             the
             calculation
             afterwards
             ,
             that
             though
             it
             be
             said
             ,
             this
             34
             foot
             of
             Water
             weighs
             400
             pound
             ,
             yet
             in
             it self
             it
             weighs
             but
             200
             :
             but
             considering
             the
             Pressure
             of
             the
             Air
             upon
             I
             K
             ,
             which
             is
             as
             much
             ,
             it
             may
             be
             truly
             said
             to
             weigh
             400.
             
             These
             things
             being
             premitted
             ;
             I
             say
             the
             weight
             that
             the
             beam
             T
             V
             sustains
             ,
             is
             not
             the
             weight
             of
             the
             inferior
             plain
             ,
             and
             the
             Lead
             R
             ,
             but
             352
             pound
             of
             the
             superior
             VVater
             I
             K
             L
             M
             ,
             and
             consequently
             ,
             that
             the
             inferior
             plain
             is
             supported
             by
             the
             lower
             VVater
             P
             Q
             N
             O.
             The
             reason
             is
             ,
             because
             the
             lower
             VVater
             presseth
             up
             ●●th
             the
             weight
             of
             48
             pound
             .
             It
             is
             in
             it self
             400
             pound
             :
             but
             being
             burdened
             with
             352
             ,
             it
             cannot
             thrust
             up
             with
             more
             weight
             than
             48.
             
             Now
             ,
             it
             pressing
             up
             with
             48
             ,
             must
             ease
             
             the
             beam
             of
             48
             ,
             and
             counterpoise
             so
             much
             of
             the
             superior
             VVater
             ,
             and
             consequently
             the
             beam
             must
             support
             only
             352
             pound
             of
             it
             .
             But
             put
             the
             case
             (
             you
             say
             )
             the
             weight
             R
             ,
             were
             130
             pound
             ,
             160
             pound
             ,
             or
             180
             pound
             ,
             would
             the
             beam
             be
             less
             or
             more
             burdened
             with
             the
             superior
             Water
             ?
             I
             answer
             ,
             if
             R
             be
             130
             pound
             ,
             then
             the
             beam
             supports
             only
             132
             pound
             of
             the
             superior
             Water
             ;
             for
             if
             the
             inferior
             be
             only
             burdened
             with
             130
             ,
             the
             weight
             of
             R
             ,
             and
             with
             two
             the
             weight
             of
             the
             inferior
             plain
             ,
             then
             must
             it
             press
             up
             with
             368
             ,
             and
             by
             this
             means
             ,
             must
             ease
             the
             beam
             of
             so
             much
             ,
             it
             sustaining
             132
             pound
             only
             .
             According
             to
             this
             compting
             ,
             when
             the
             Lead
             R
             weighs
             160
             pound
             ,
             the
             beam
             supports
             only
             238
             pound
             of
             the
             superior
             Water
             .
             If
             it
             weigh
             180
             pound
             ,
             it
             sustains
             218.
             
             And
             if
             the
             weight
             R
             were
             taken
             away
             ,
             the
             beam
             supports
             no
             more
             of
             the
             superior
             VVater
             than
             two
             pound
             .
          
           
             To
             proceed
             a
             little
             further
             ;
             imagine
             the
             two
             Plains
             to
             be
             drawn
             up
             17
             foot
             nearer
             the
             first
             surface
             I
             K
             ,
             namely
             as
             high
             as
             Z
             W.
             This
             done
             ,
             the
             union
             breaks
             up
             ,
             and
             they
             presently
             fall
             asunder
             .
             The
             reason
             is
             ,
             because
             ▪
             the
             surface
             Z
             W
             is
             not
             able
             to
             support
             352
             pound
             ,
             but
             only
             300
             ,
             which
             I
             prove
             thus
             .
             If
             68
             foot
             sustain
             400
             ,
             then
             51
             foot
             must
             sustain
             300.
             
             I
             say
             68
             ,
             and
             not
             34
             ,
             because
             as
             was
             noted
             ,
             the
             Pressure
             of
             the
             Air
             upon
             the
             surface
             I
             K
             ,
             is
             equivalent
             to
             other
             34
             foot
             :
             and
             therefore
             though
             the
             deepness
             of
             this
             VVater
             ,
             between
             I
             K
             and
             L
             M
             be
             but
             34
             foot
             really
             ,
             yet
             it
             is
             68
             foot
             virtually
             ,
             and
             in
             effect
             .
             Imagine
             secondly
             the
             surface
             I
             K
             to
             subside
             17
             foot
             ,
             namely
             to
             Z
             W.
             In
             this
             case
             the
             union
             is
             broken
             also
             ,
             and
             the
             lower
             Plain
             falls
             from
             the
             upper
             .
             The
             reason
             of
             this
             ,
             is
             the
             same
             with
             the
             former
             ;
             because
             by
             what
             proportion
             you
             diminish
             the
             high
             of
             the
             superior
             VVater
             ,
             by
             that
             
             same
             proportion
             you
             diminish
             the
             upward
             Pressure
             of
             the
             lower
             VVater
             .
             Therefore
             ,
             if
             you
             subtract
             from
             the
             superior
             VVater
             17
             foot
             ,
             that
             weighs
             100
             pound
             ,
             you
             subtract
             likewise
             100
             pound
             from
             the
             inferior
             VVater
             ,
             and
             consequently
             ,
             you
             make
             it
             press
             up
             only
             with
             300
             ,
             but
             300
             is
             not
             able
             to
             counterpoise
             352.
             
          
           
             Let
             us
             suppose
             thirdly
             ,
             the
             superior
             Plain
             ,
             and
             the
             superior
             Water
             to
             be
             annihilated
             ;
             then
             I
             say
             ,
             the
             Pressure
             and
             force
             of
             the
             under
             Water
             would
             thrust
             up
             the
             inferior
             Plain
             and
             the
             weight
             R
             about
             eight
             foot
             higher
             then
             X
             Y
             and
             there
             suspend
             them
             .
             The
             reason
             is
             ,
             because
             the
             surface
             X
             Y
             ,
             being
             able
             to
             sustain
             400
             ,
             and
             being
             burdened
             only
             with
             352
             ,
             must
             have
             the
             weight
             of
             48.
             
             Now
             the
             upper
             Plain
             being
             taken
             away
             ,
             and
             the
             upper
             Water
             also
             ,
             and
             the
             empty
             space
             of
             both
             remaining
             ,
             the
             said
             weight
             of
             48
             pound
             ,
             must
             carry
             the
             under
             Plain
             as
             high
             as
             is
             said
             .
             Let
             us
             suppose
             fourthly
             ,
             the
             Pressure
             of
             the
             Element
             of
             Air
             ,
             that
             rests
             upon
             I
             K
             ,
             to
             be
             taken
             away
             ,
             then
             must
             the
             two
             Plain
             bodies
             be
             disunited
             ,
             the
             inferior
             falling
             from
             the
             superior
             .
             The
             reason
             is
             ,
             because
             in
             this
             case
             ,
             the
             superior
             Water
             would
             have
             but
             the
             weight
             of
             200
             pound
             ,
             and
             consequently
             the
             inferior
             ,
             would
             press
             up
             only
             with
             as
             much
             :
             but
             200
             is
             not
             able
             to
             counterpoise
             352.
             
          
           
             From
             what
             is
             said
             we
             see
             first
             ,
             that
             in
             all
             Fluids
             there
             is
             an
             upward
             Pressure
             ,
             as
             well
             as
             a
             downward
             ;
             and
             that
             the
             one
             is
             alwayes
             of
             equal
             force
             to
             the
             other
             :
             because
             the
             inferior
             Plain
             is
             pressed
             up
             with
             as
             great
             force
             ,
             as
             the
             superior
             Plain
             is
             pressed
             down
             with
             .
             We
             see
             secondly
             ,
             that
             in
             Fluids
             ,
             there
             is
             a
             Pondus
             and
             a
             Potentia
             .
             The
             Potenti●
             here
             is
             the
             inferior
             Water
             ,
             and
             the
             Pondus
             is
             the
             superior
             .
             Or
             ,
             the
             350
             pound
             of
             Lead
             R
             ,
             may
             be
             called
             the
             Pondus
             ,
             which
             counterpoiseth
             the
             Potentia
             of
             the
             surface
             
             of
             VVater
             X
             Y.
             We
             see
             thirdly
             ,
             that
             though
             the
             Pressure
             of
             a
             Fluid
             ,
             be
             not
             the
             same
             thing
             with
             the
             natural
             weight
             ,
             yet
             it
             is
             equivalent
             to
             it
             :
             because
             the
             352
             pound
             of
             Lead
             R
             ,
             is
             sustained
             by
             the
             Pressure
             of
             the
             inferior
             VVater
             ,
             which
             could
             not
             be
             ,
             unless
             they
             were
             virtually
             the
             same
             .
             We
             see
             fourthly
             ,
             that
             there
             may
             be
             as
             much
             Pressure
             in
             one
             foot
             of
             Water
             ,
             as
             there
             is
             weight
             in
             100
             ,
             or
             in
             1000
             foot
             ,
             or
             in
             1000
             fathom
             ,
             For
             put
             the
             case
             ,
             these
             two
             plain
             bodies
             were
             suspended
             ,
             100
             fathom
             below
             the
             surface
             of
             the
             sea
             ,
             and
             within
             a
             foot
             or
             two
             of
             the
             ground
             ,
             as
             much
             weight
             would
             be
             required
             to
             pull
             them
             asunder
             ,
             as
             is
             the
             weight
             of
             a
             Pillar
             of
             Water
             100
             fathom
             high
             ,
             and
             4
             inches
             thick
             every
             way
             ,
             which
             will
             be
             more
             then
             3000
             pound
             weight
             ,
             besides
             the
             weight
             of
             the
             Air
             above
             ,
             that
             will
             weigh
             200
             pound
             .
             This
             could
             not
             be
             ,
             unless
             there
             were
             as
             much
             Pressure
             in
             the
             lowest
             foot
             of
             this
             Water
             ,
             that
             's
             100
             fathom
             deep
             ,
             as
             there
             is
             weight
             in
             the
             whole
             Pillar
             above
             .
             We
             see
             fifthly
             ,
             the
             more
             the
             potentia
             of
             a
             surface
             is
             burdened
             ,
             the
             more
             sensible
             is
             the
             pondus
             :
             because
             the
             heavier
             you
             make
             the
             Lead
             R
             ,
             that
             burdens
             the
             inferior
             Water
             ,
             the
             more
             weight
             of
             the
             superior
             Water
             rests
             upon
             the
             Beam.
             We
             see
             sixthly
             ,
             the
             more
             unequally
             a
             body
             is
             pressed
             ,
             the
             more
             the
             Pressure
             is
             sensible
             .
             For
             understanding
             this
             ,
             consider
             that
             the
             under-face
             of
             the
             superior
             Plain
             ,
             is
             more
             and
             less
             pressed
             ,
             according
             to
             the
             more
             and
             less
             weight
             the
             Lead
             R
             is
             of
             :
             for
             put
             the
             case
             ,
             the
             inferior
             Plain
             were
             taken
             away
             ,
             the
             face
             of
             the
             superior
             Plain
             ,
             would
             be
             equally
             prest
             with
             the
             back
             of
             it
             .
             But
             ●hen
             the
             inferior
             Plain
             is
             united
             to
             it
             ,
             the
             Pressure
             of
             the
             Water
             is
             kept
             off
             ;
             by
             which
             means
             the
             back
             is
             prest
             more
             than
             the
             face
             .
             Now
             ,
             as
             the
             inferior
             Plain
             becomes
             heavier
             and
             heavier
             ,
             by
             making
             the
             weight
             R
             more
             and
             more
             
             weighty
             ,
             the
             less
             and
             less
             is
             the
             face
             of
             the
             superior
             Plain
             prest
             up
             .
             Hence
             it
             is
             ,
             that
             as
             this
             inequality
             of
             Pressure
             becomes
             greater
             and
             greater
             ;
             so
             the
             weight
             of
             the
             superior
             Water
             ,
             affects
             the
             Beam
             more
             and
             more
             .
             Or
             ,
             if
             the
             superior
             Plain
             were
             a
             sensible
             body
             ,
             as
             Animals
             are
             ,
             it
             would
             find
             the
             back
             of
             it
             more
             and
             more
             burdened
             ,
             according
             as
             the
             weight
             R
             ,
             becomes
             heavier
             and
             heavier
             .
             We
             see
             seventhly
             ,
             that
             Water
             weighs
             in
             Water
             :
             because
             all
             the
             weight
             the
             Beam
             supports
             ,
             is
             the
             burden
             of
             the
             superior
             VVater
             ,
             and
             not
             the
             burden
             of
             the
             inferior
             Plain
             ,
             or
             of
             the
             weight
             R.
             It
             supports
             the
             weight
             also
             of
             the
             superior
             Plain
             ,
             but
             this
             is
             not
             considerable
             .
             This
             is
             only
             to
             be
             understood
             ,
             when
             the
             Pressure
             is
             unequal
             ;
             for
             if
             the
             upper
             Plain
             were
             as
             much
             prest
             up
             ,
             as
             it
             's
             prest
             down
             ,
             the
             weight
             of
             the
             superior
             VVater
             would
             not
             be
             found
             by
             the
             Beam.
             We
             see
             eighthly
             ,
             that
             the
             higher
             a
             surface
             be
             ,
             it
             is
             the
             weaker
             ;
             and
             the
             lower
             it
             be
             ,
             it
             is
             the
             stronger
             :
             because
             when
             the
             two
             plain
             bodies
             are
             pulled
             up
             ,
             17
             foot
             ,
             they
             fall
             asunder
             .
             We
             see
             ninthly
             ,
             the
             vanity
             of
             the
             common
             opinion
             ,
             that
             maintains
             two
             plain
             bodies
             to
             cleave
             closs
             together
             for
             fear
             of
             vacuity
             ;
             and
             that
             neither
             Humane
             not
             Angelick
             strength
             is
             able
             to
             break
             this
             union
             ,
             without
             the
             rupture
             and
             fracture
             of
             them
             both
             .
          
           
             It
             may
             be
             enquired
             ,
             upon
             supposition
             ,
             that
             the
             inferior
             plain
             had
             four
             holes
             cut
             thorow
             the
             middle
             ,
             square-wise
             ,
             as
             A
             B
             C
             D
             in
             the
             18
             Figure
             ,
             what
             Phenomena
             would
             follow
             ?
             Before
             I
             answer
             ,
             consider
             that
             this
             Figure
             represents
             the
             inner
             face
             of
             the
             Brass-plate
             C
             D
             N
             O
             ,
             of
             the
             17
             Figure
             ,
             which
             as
             was
             supposed
             ,
             is
             four
             inches
             from
             〈◊〉
             to
             side
             ,
             and
             consequently
             contains
             16
             square
             inches
             .
             Now
             ,
             imagine
             the
             under
             plain
             C
             D
             N
             O
             ,
             while
             it
             is
             united
             to
             the
             uppermost
             ,
             to
             have
             four
             square
             inches
             cutted
             out
             of
             it
             ,
             
             as
             A
             B
             C
             D.
             These
             things
             being
             rightly
             conceived
             ,
             and
             understood
             ,
             I
             say
             ,
             when
             the
             said
             holes
             are
             cutted
             thorow
             ;
             the
             beam
             T
             V
             ,
             that
             now
             sustains
             350
             pound
             ,
             shall
             by
             this
             means
             ,
             only
             sustain
             250
             pound
             .
             To
             make
             this
             evident
             ;
             consider
             that
             the
             under
             plain
             (
             as
             was
             said
             )
             contains
             16
             square
             inches
             .
             Next
             ,
             that
             the
             top
             of
             the
             inferior
             Water
             upon
             which
             the
             plain
             rests
             ,
             contains
             as
             many
             ,
             and
             that
             every
             inch
             of
             the
             Water
             weighs
             25
             pound
             ,
             seing
             the
             whole
             ,
             as
             was
             supposed
             before
             ,
             weighs
             400
             pound
             .
             Now
             ,
             I
             say
             ,
             the
             beam
             must
             support
             only
             250
             pound
             of
             the
             Water
             I
             K
             L
             M
             ;
             because
             ,
             these
             holes
             being
             made
             ,
             the
             top
             of
             the
             inferior
             Water
             comes
             through
             them
             ,
             and
             presseth
             up
             the
             face
             of
             the
             superior
             plain
             with
             100
             pound
             ,
             and
             so
             easeth
             the
             beam
             of
             so
             much
             .
             I
             affirm
             next
             ,
             that
             though
             the
             inferior
             Water
             N
             O
             P
             Q
             be
             in
             it self
             400
             pound
             ,
             and
             consequently
             able
             to
             support
             the
             inferior
             plain
             ,
             with
             the
             weight
             R
             ,
             albeit
             they
             weighed
             so
             much
             ,
             yet
             the
             said
             holes
             being
             cut
             out
             ,
             it
             is
             not
             able
             to
             support
             more
             burden
             than
             300.
             
             The
             reason
             is
             ,
             because
             of
             16
             parts
             that
             did
             actually
             bear
             up
             before
             ,
             there
             are
             only
             12
             now
             that
             sustains
             .
             And
             every
             one
             of
             these
             twelve
             ,
             being
             but
             able
             to
             support
             25
             pound
             ,
             it
             necessarily
             follows
             ,
             that
             the
             greatest
             weight
             they
             are
             able
             to
             sustain
             ,
             is
             300
             pound
             .
             I
             affirm
             thirdly
             ,
             that
             if
             a
             fifth
             hole
             were
             cut
             through
             ,
             the
             under
             plain
             would
             fall
             from
             the
             upper
             ;
             because
             in
             this
             case
             ,
             the
             inferior
             Water
             is
             not
             able
             to
             support
             350
             pound
             as
             before
             ,
             seing
             of
             16
             parts
             ,
             there
             are
             five
             wanting
             ,
             and
             eleven
             remaining
             ,
             cannot
             support
             more
             weight
             than
             275
             pound
             .
             Moe
             questions
             of
             this
             kind
             might
             ●e
             proposed
             ;
             as
             first
             ,
             what
             would
             come
             to
             pass
             ,
             if
             the
             the
             upper
             plain
             had
             as
             many
             holes
             cut
             through
             it
             ,
             answering
             to
             the
             four
             of
             the
             nether
             ?
             Secondly
             ,
             what
             would
             folow
             ▪
             if
             the
             nether
             plain
             were
             intire
             ,
             and
             four
             bored
             through
             
             the
             upper
             ?
             But
             I
             shall
             supersede
             ,
             and
             leave
             these
             to
             be
             gathered
             by
             the
             judicious
             Reader
             .
          
           
             From
             this
             Experiment
             we
             see
             first
             ,
             that
             the
             broader
             and
             larger
             a
             surface
             of
             a
             Fluid
             be
             ,
             it
             's
             the
             more
             able
             to
             sustain
             a
             burden
             ,
             and
             the
             narrower
             it
             be
             ,
             't
             is
             the
             less
             able
             .
             Secondly
             ,
             that
             each
             part
             of
             a
             surface
             ,
             is
             able
             to
             sustain
             so
             much
             weight
             ,
             and
             no
             more
             ,
             and
             no
             less
             .
          
           
           
           
             From
             what
             is
             said
             ,
             we
             shall
             only
             in●err
             this
             conclusion
             ,
             that
             equality
             of
             hight
             between
             Pillars
             of
             a
             Fluid
             makes
             equal
             Pressure
             ,
             and
             inequality
             of
             hight
             makes
             unequal
             Pressure
             .
             Therefore
             't
             is
             no
             matter
             ,
             whether
             they
             be
             gross
             or
             small
             ,
             thick
             or
             slender
             ,
             provided
             they
             be
             all
             of
             the
             same
             Altitude
             .
          
        
         
           
           
             EXPERIMENT
             XIV
             .
             Figure
             20.
             
          
           
             THis
             Schematism
             represents
             a
             Vessel
             full
             of
             Water
             8
             foot
             deep
             .
             E
             F
             is
             a
             Glass-Pipe
             ,
             open
             at
             both
             ends
             ,
             about
             9
             foot
             high
             ,
             and
             one
             inch
             in
             Diameter
             .
             A
             B
             C
             D
             is
             a
             Vessel
             of
             Glass
             ,
             or
             of
             any
             other
             metal
             ,
             thorow
             whose
             orifice
             above
             ,
             the
             said
             Pipe
             comes
             down
             .
             B
             H
             I
             is
             a
             Pipe
             going
             out
             from
             the
             said
             Vessel
             ,
             crooked
             with
             a
             right
             angle
             at
             H
             ,
             that
             the
             orifice
             I
             may
             look
             upwards
             .
             That
             some
             Hydrostatical
             conclusions
             may
             be
             inferred
             from
             this
             Experiment
             ,
             fill
             the
             lower
             Vessel
             A
             B
             C
             D
             with
             Quick-silver
             almost
             ;
             then
             pour
             in
             as
             much
             Water
             above
             it
             ,
             as
             will
             fill
             the
             space
             A
             B
             H
             ,
             leaving
             from
             H
             to
             I
             full
             of
             Air.
             Next
             ,
             thrust
             down
             the
             orifice
             of
             the
             Pipe
             E
             ,
             below
             the
             said
             Water
             and
             Mercury
             ,
             till
             it
             rest
             upon
             the
             bottom
             C
             D.
             Lastly
             ,
             stop
             well
             with
             cement
             the
             passage
             of
             the
             lower
             Vessel
             ,
             through
             which
             the
             Pipe
             came
             down
             ,
             that
             neither
             Air
             nor
             Water
             may
             go
             out
             ,
             or
             come
             in
             .
             These
             things
             being
             done
             ,
             let
             down
             this
             Engine
             to
             the
             bottom
             of
             the
             large
             Vessel
             ,
             which
             ,
             as
             was
             noted
             ,
             is
             full
             of
             VVater
             from
             M
             N
             to
             K
             L
             ,
             8
             foot
             ,
             and
             you
             will
             find
             the
             Mercury
             to
             rise
             in
             the
             Pipe
             from
             A
             B
             to
             G
             ,
             6
             inches
             ,
             and
             more
             .
             The
             reason
             is
             ,
             because
             there
             is
             a
             Pillar
             of
             VVater
             K
             I
             ,
             that
             enters
             the
             orifice
             I
             ,
             and
             presseth
             down
             the
             Air
             ,
             from
             I
             to
             P
             ,
             3
             inches
             ,
             which
             before
             was
             6.
             
             This
             Air
             being
             so
             burdened
             ;
             instantly
             presseth
             forward
             the
             VVater
             H
             B
             A
             :
             and
             this
             pressing
             the
             surface
             of
             the
             stagnant
             Mercury
             A
             B
             ,
             causes
             the
             liquor
             run
             up
             the
             Pipe
             from
             A
             B
             to
             G
             ,
             6
             inches
             :
             The
             reason
             ,
             why
             it
             riseth
             6
             inches
             ,
             is
             this
             :
             between
             the
             surface
             of
             the
             stagnant
             Mercury
             A
             B
             ,
             and
             the
             top
             of
             the
             
             Water
             L
             O
             K
             ,
             are
             84
             inches
             .
             Now
             Water
             being
             14
             times
             naturally
             lighter
             then
             Mercury
             ,
             there
             must
             be
             14
             inches
             of
             Water
             ,
             required
             for
             sustaining
             one
             inch
             of
             Mercury
             ,
             and
             consequently
             84
             ,
             for
             supporting
             6.
             
             For
             a
             second
             trial
             ,
             lift
             up
             the
             whole
             Engine
             to
             the
             top
             of
             the
             Water
             ,
             and
             you
             will
             find
             the
             6
             inches
             of
             Mercury
             B
             G
             sink
             down
             ,
             and
             become
             no
             higher
             within
             the
             Pipe
             ,
             than
             the
             surface
             of
             the
             stagnant
             Mercury
             A
             B
             without
             .
             The
             reason
             is
             ,
             because
             by
             coming
             up
             above
             the
             Water
             ,
             the
             Pressure
             of
             the
             Water
             K
             I
             ,
             is
             taken
             away
             from
             the
             orifice
             I
             ,
             by
             which
             means
             the
             comprest
             Air
             H
             P
             ,
             extending
             it self
             to
             I
             ,
             liberats
             the
             Water
             A
             B
             H
             of
             the
             Pressure
             it
             had
             ,
             and
             this
             freeth
             the
             Mercury
             of
             its
             Pressure
             ,
             and
             so
             the
             6
             inches
             falls
             down
             .
             For
             a
             third
             trial
             ,
             stop
             closely
             the
             orifice
             I
             ,
             and
             let
             all
             down
             as
             before
             .
             In
             this
             case
             ,
             you
             will
             find
             no
             ascent
             of
             Mercury
             from
             B
             to
             G
             :
             because
             the
             Water
             K
             I
             cannot
             have
             access
             to
             thrust
             down
             the
             Air
             from
             I
             to
             P
             ,
             as
             formerly
             .
          
           
             For
             a
             fourth
             ,
             open
             the
             said
             orifice
             I
             ,
             while
             the
             Engine
             is
             below
             the
             Water
             ,
             and
             you
             will
             find
             the
             Mercury
             rise
             from
             B
             to
             G
             :
             because
             the
             Pillar
             of
             Water
             K
             I
             ,
             hath
             now
             access
             to
             press
             .
             For
             a
             fifth
             trial
             ,
             stop
             the
             orifice
             I
             ,
             and
             bring
             up
             all
             to
             the
             top
             ,
             and
             you
             will
             find
             the
             six
             inches
             of
             Mercury
             B
             G
             suspended
             ,
             as
             if
             the
             Engine
             were
             under
             the
             Water
             .
             The
             reason
             is
             ,
             because
             the
             stopping
             of
             the
             orifice
             ,
             keeps
             the
             inclosed
             Air
             P
             H
             ,
             under
             the
             same
             degree
             of
             Pressure
             it
             obtained
             from
             the
             Water
             K
             I.
             For
             a
             sixth
             proof
             ,
             open
             the
             same
             orifice
             I
             ,
             while
             the
             Engine
             is
             above
             the
             Water
             ,
             and
             you
             will
             find
             the
             six
             inches
             of
             Mercury
             fall
             down
             ,
             because
             the
             imprisoned
             Air
             H
             P
             ,
             obtains
             now
             its
             liberty
             ;
             and
             expanding
             it self
             from
             H
             to
             I
             ,
             eases
             the
             Water
             B
             H
             of
             the
             burden
             it
             was
             under
             .
             For
             a
             seventh
             ,
             pour
             in
             14
             
             inches
             of
             Water
             at
             the
             orifice
             F
             ,
             till
             it
             rest
             upon
             the
             top
             of
             the
             Mercury
             at
             G
             ,
             and
             you
             will
             find
             one
             inch
             fall
             down
             .
             Pour
             in
             as
             much
             ,
             and
             two
             inches
             falls
             down
             .
             In
             a
             word
             ,
             pour
             in
             as
             much
             Water
             ,
             as
             will
             fill
             the
             Pipe
             to
             O
             ,
             and
             you
             will
             find
             the
             whole
             six
             inches
             fall
             down
             .
             The
             reason
             is
             ,
             because
             the
             Water
             K
             I
             ,
             is
             not
             able
             to
             sustain
             ,
             both
             the
             six
             inches
             of
             Mercury
             and
             the
             Water
             ,
             that
             's
             poured
             in
             ;
             any
             one
             of
             them
             being
             able
             and
             sufficient
             to
             counterpoise
             it
             ,
             For
             an
             eighth
             trial
             ,
             empty
             the
             Pipe
             of
             the
             said
             Water
             ,
             and
             after
             the
             Mercury
             is
             ascended
             from
             A
             B
             to
             G
             ,
             as
             formerly
             ,
             suck
             out
             the
             whole
             Air
             between
             G
             and
             F
             ,
             and
             you
             will
             find
             the
             Mercury
             to
             rise
             from
             G
             to
             R
             29
             inches
             .
             The
             reason
             of
             this
             is
             evident
             from
             the
             Pillar
             of
             Air
             S
             K
             ,
             that
             rests
             upon
             the
             top
             of
             the
             Pillar
             of
             Water
             K
             I
             :
             for
             by
             sucking
             out
             the
             said
             Air
             ,
             you
             take
             away
             the
             pondus
             or
             weight
             ,
             that
             counterpoised
             the
             weight
             of
             the
             Pillar
             S
             K
             ,
             therefore
             it
             finding
             its
             counterpoise
             removed
             ,
             presently
             causeth
             the
             Water
             K
             I
             ,
             to
             enter
             farder
             within
             the
             crooked
             Pipe
             ,
             till
             it
             hath
             prest
             up
             the
             liquor
             to
             R.
             For
             a
             ninth
             trial
             ,
             take
             the
             six
             inches
             of
             Mercury
             B
             G
             ,
             and
             put
             them
             into
             the
             scale
             of
             a
             ballance
             ;
             then
             take
             as
             much
             Water
             ,
             as
             will
             fill
             the
             Tub
             between
             A
             B
             and
             O
             ,
             and
             put
             it
             into
             the
             other
             scale
             ,
             and
             you
             will
             find
             a
             most
             exact
             counterballance
             between
             them
             .
             The
             reason
             is
             ,
             because
             if
             the
             Water
             K
             H
             ,
             or
             a
             Pillar
             of
             that
             hight
             ,
             be
             able
             to
             raise
             and
             counterpoise
             the
             Mercury
             B
             G
             ;
             then
             must
             as
             much
             Water
             ,
             as
             fills
             the
             Pipe
             betwen
             B
             and
             O
             ,
             be
             the
             just
             weight
             of
             it
             .
             The
             reason
             of
             this
             consequence
             is
             ,
             because
             these
             two
             Waters
             are
             of
             the
             same
             weight
             :
             therefore
             ,
             if
             the
             one
             be
             the
             just
             weight
             of
             it
             ,
             the
             other
             must
             be
             so
             too
             .
             If
             it
             be
             said
             ,
             that
             the
             Water
             ,
             that
             fills
             the
             Pipe
             between
             B
             and
             O
             ,
             is
             far
             
             thicker
             ,
             then
             the
             Water
             K
             H
             ;
             therefore
             they
             cannot
             be
             both
             of
             one
             weight
             .
             I
             answer
             ,
             equality
             of
             altitude
             ,
             in
             this
             
               Ballance
               of
               Nature
            
             ,
             is
             equality
             of
             weight
             :
             therefore
             seing
             the
             one
             Water
             ,
             is
             as
             high
             as
             the
             other
             ,
             they
             must
             be
             both
             of
             one
             weight
             .
             If
             it
             be
             said
             ,
             that
             a
             Pillar
             of
             Water
             between
             K
             and
             H
             ,
             cannot
             counterpoise
             the
             six
             inches
             of
             Mercury
             B
             G
             ,
             both
             being
             put
             into
             a
             ballance
             :
             and
             the
             reason
             is
             ,
             because
             the
             one
             is
             thicker
             than
             the
             other
             .
             I
             answer
             ,
             this
             only
             proves
             that
             two
             Pillars
             differing
             in
             weight
             in
             the
             Libra
             or
             
               Artificial
               Ballance
            
             ,
             may
             be
             of
             one
             weight
             in
             the
             
               Natural
               Ballance
            
             :
             because
             in
             the
             
               Artificial
               Ballance
            
             ,
             bodies
             counterpoise
             one
             another
             ,
             according
             to
             all
             their
             dimensions
             ,
             but
             in
             the
             
               Natural
               Ballance
            
             ,
             such
             as
             this
             Engine
             is
             ,
             Fluids
             counterpoise
             one
             another
             ,
             according
             to
             their
             altitude
             only
             .
          
           
             From
             the
             first
             trial
             ,
             we
             conclude
             first
             ,
             that
             Water
             even
             in
             its
             own
             place
             gravitats
             and
             weighs
             ,
             because
             this
             Water
             by
             its
             Pressure
             ,
             
               de
               facto
            
             thrusts
             up
             6
             inches
             of
             Mercury
             .
             We
             see
             in
             the
             next
             place
             ,
             that
             the
             Pressure
             of
             a
             Fluid
             ,
             is
             as
             easily
             communicated
             Horizontally
             ;
             as
             Perpendicularly
             ;
             because
             the
             Pressure
             runs
             alongst
             from
             H
             to
             B.
             We
             see
             thirdly
             ,
             that
             Fluids
             ;
             may
             have
             as
             much
             Pressure
             begotten
             in
             them
             ,
             even
             while
             they
             are
             environed
             about
             closely
             with
             solid
             bodies
             ,
             whereby
             the
             superior
             Pressure
             ,
             immediatly
             and
             directly
             by
             perpendicular
             lines
             is
             keeped
             off
             ,
             as
             if
             they
             were
             immediatly
             under
             the
             Pressure
             :
             because
             the
             Mercury
             A
             B
             C
             D
             ,
             is
             as
             much
             burdened
             with
             the
             Pressure
             ,
             that
             comes
             from
             H
             ,
             as
             if
             the
             upper
             part
             of
             the
             Vessel
             A
             B
             ,
             were
             open
             to
             let
             in
             the
             superior
             Pressure
             ,
             by
             perpendicular
             lines
             .
             The
             Air
             then
             under
             the
             roof
             of
             a
             house
             ,
             is
             under
             as
             great
             a
             Bensil
             and
             Pressure
             ,
             as
             the
             Air
             without
             ,
             that
             's
             directly
             under
             the
             Pressure
             of
             the
             Atmosphere
             .
             
             VVe
             see
             fourthly
             ,
             that
             the
             Pressure
             of
             a
             Fluid
             ,
             may
             be
             as
             easily
             communicated
             thorow
             the
             parts
             of
             Heterogeneous
             Fluids
             ,
             as
             thorow
             the
             parts
             of
             Homogeneous
             ;
             because
             the
             Pressure
             of
             the
             VVater
             K
             I
             ,
             is
             as
             easily
             communicated
             thorow
             the
             Air
             P
             H
             ,
             thorow
             the
             Water
             H
             B
             ,
             and
             thorow
             the
             stagnant
             Mercury
             ▪
             B
             D
             to
             the
             orifice
             E
             ,
             as
             if
             nothing
             interveened
             but
             VVater
             .
             VVe
             see
             fifthly
             ,
             that
             Mercury
             can
             suffer
             a
             Pressure
             ,
             as
             well
             as
             VVater
             or
             Air
             ;
             because
             the
             six
             inches
             cannot
             rise
             from
             B
             to
             G
             ,
             unless
             the
             stagnant
             Mercury
             A
             B
             C
             D
             were
             compressed
             ,
             even
             in
             all
             the
             parts
             of
             it
             .
          
           
             From
             the
             second
             trial
             ,
             we
             see
             ,
             that
             there
             cannot
             be
             a
             Pondus
             in
             a
             Fluid
             ,
             unless
             there
             be
             a
             Potentia
             ,
             to
             counterpoise
             it
             :
             for
             when
             you
             take
             away
             the
             Water
             ▪
             R
             I
             ,
             by
             lifting
             up
             the
             Engine
             to
             the
             top
             of
             the
             Water
             ,
             the
             Mercury
             B
             G
             presently
             falls
             down
             .
             From
             the
             third
             trial
             ,
             we
             conclude
             ,
             that
             the
             Pressure
             of
             a
             Fluid
             ,
             cannot
             be
             communicated
             thorow
             solid
             Bodies
             :
             for
             when
             the
             Engine
             is
             drowned
             below
             the
             Water
             ,
             with
             the
             orifice
             I
             ,
             stopped
             ,
             no
             ascent
             of
             Mercury
             follows
             .
             We
             conclude
             from
             the
             fourth
             trial
             ,
             that
             it
             is
             impossible
             for
             two
             Fluids
             to
             counterpoise
             one
             another
             ,
             unless
             they
             be
             
               in
               Equilibrio
            
             ;
             because
             the
             Water
             K
             I
             cannot
             sustain
             the
             Mercury
             B
             G
             ,
             unless
             it
             be
             of
             the
             same
             weight
             .
             From
             the
             fifth
             ,
             we
             conclude
             ,
             that
             a
             Fluid
             may
             be
             keeped
             under
             the
             same
             degree
             of
             compression
             ,
             after
             the
             superior
             weight
             that
             begat
             it
             ,
             is
             taken
             away
             :
             for
             after
             the
             Engine
             is
             brought
             above
             the
             Water
             ,
             with
             the
             orifice
             I
             stopped
             ,
             the
             Mercury
             B
             G
             is
             still
             suspended
             ,
             even
             by
             vertue
             of
             the
             Pressure
             ,
             that
             's
             in
             the
             stagnant
             Mercury
             .
             This
             tells
             us
             ,
             that
             a
             sphere
             of
             glass
             full
             of
             Air
             ,
             may
             retain
             its
             Bensil
             ,
             even
             though
             the
             whole
             Element
             of
             Air
             ,
             that
             begat
             it
             ,
             were
             destroyed
             .
             From
             the
             
             sixth
             we
             gather
             ,
             that
             a
             Fluid
             cannot
             abide
             under
             Pressure
             ,
             when
             the
             burden
             is
             taken
             away
             that
             begat
             it
             ,
             or
             that
             keeped
             it
             under
             Pressure
             :
             for
             by
             opening
             the
             orifice
             I
             ,
             the
             Air
             P
             H
             extends
             it self
             :
             and
             so
             are
             the
             VVater
             ,
             and
             Mercury
             within
             the
             Vessel
             freed
             of
             their
             Pressure
             likewise
             .
             We
             gather
             from
             the
             seventh
             trial
             ,
             that
             in
             the
             Ballance
             of
             Nature
             ,
             one
             Scale
             cannot
             be
             more
             burdened
             then
             another
             ;
             or
             that
             two
             Fluids
             cannot
             counterpoise
             one
             another
             ,
             unless
             they
             be
             
               in
               equilibrio
            
             :
             for
             when
             you
             pour
             in
             14
             inches
             of
             Water
             ,
             upon
             the
             top
             of
             the
             Mercury
             at
             G
             ,
             they
             thrust
             down
             one
             inch
             ,
             that
             there
             may
             be
             a
             just
             equipondium
             ,
             between
             them
             ,
             and
             the
             opposite
             weight
             K
             I.
             We
             gather
             from
             the
             eighth
             trial
             ,
             which
             was
             observed
             before
             ;
             first
             ,
             that
             there
             cannot
             be
             a
             Potentia
             in
             a
             Fluid
             ,
             unless
             there
             be
             a
             Pondus
             to
             counterpoise
             it
             :
             for
             when
             you
             suck
             out
             the
             Air
             G
             O
             ,
             which
             was
             the
             Pondus
             ,
             that
             counterpoised
             the
             Air
             S
             K
             ,
             this
             presently
             in
             stead
             of
             it
             ,
             raiseth
             29
             inches
             of
             Mercury
             from
             G
             to
             R.
             We
             see
             secondly
             ,
             that
             one
             pillat
             of
             Air
             can
             counterpoise
             another
             ,
             Fluids
             of
             diverse
             kinds
             interveening
             :
             because
             the
             Air
             S
             K
             ,
             counterpoises
             the
             Air
             within
             the
             Pipe
             G
             O
             ,
             the
             VVater
             K
             P
             first
             interveening
             ;
             the
             Air
             P
             H
             next
             interveening
             ,
             and
             the
             stagnant
             ,
             and
             suspended
             Mercury
             interveening
             also
             .
             We
             see
             thirdly
             from
             this
             eighth
             trial
             ,
             that
             the
             Pressure
             of
             the
             Atmosphere
             ,
             may
             be
             communicated
             thorow
             diverse
             kinds
             of
             Fluids
             ,
             without
             the
             least
             diminution
             of
             its
             weight
             :
             because
             the
             weight
             of
             the
             Pillar
             of
             Air
             S
             K
             ,
             is
             communicated
             ,
             and
             sent
             down
             thorow
             the
             Water
             K
             I
             ,
             thorow
             the
             Air
             P
             H
             ,
             thorow
             the
             VVater
             H
             B
             ,
             thorow
             the
             stagnant
             Mercury
             B
             D
             ,
             and
             up
             thorow
             the
             suspended
             Mercury
             B
             G
             ,
             till
             it
             suspend
             the
             29
             inches
             between
             G
             and
             R
             ,
             which
             is
             the
             just
             counterballance
             of
             it
             .
             We
             see
             moreover
             ,
             that
             Fluids
             counterpoise
             
             one
             another
             ,
             according
             to
             altitude
             only
             ,
             and
             not
             according
             to
             thickness
             and
             breadth
             ;
             by
             comparing
             the
             Water
             K
             I
             ,
             that
             's
             but
             half
             an
             inch
             thick
             ,
             to
             the
             Mercury
             B
             G
             ,
             that
             's
             a
             whole
             inch
             thick
             .
             We
             see
             from
             the
             last
             trial
             ,
             that
             when
             a
             Fluid
             is
             necessitated
             ,
             to
             counterpoise
             a
             Fluid
             of
             another
             kind
             ,
             in
             stead
             of
             a
             Fluid
             of
             its
             own
             kind
             ,
             it
             sustains
             no
             more
             of
             it
             ,
             than
             what
             is
             the
             just
             weight
             of
             the
             Fluid
             of
             its
             own
             kind
             ,
             because
             the
             VVater
             K
             I
             ,
             being
             under
             a
             necessity
             to
             counterpoise
             the
             Mercury
             B
             G
             ,
             in
             stead
             of
             so
             much
             VVater
             as
             would
             fill
             the
             Tub
             ,
             it
             sustains
             no
             more
             of
             it
             ,
             than
             the
             just
             weight
             of
             so
             much
             VVater
             ,
             as
             is
             said
             .
             We
             see
             secondly
             ,
             that
             when
             two
             Fluids
             of
             divers
             kinds
             ,
             do
             counterpoise
             one
             another
             ,
             that
             which
             is
             heaviest
             
               in
               speciè
            
             ,
             hath
             alwayes
             the
             shortest
             Cylinder
             .
             Next
             ,
             that
             the
             difference
             between
             their
             altitudes
             ,
             is
             most
             exactly
             according
             to
             the
             difference
             between
             their
             natural
             weights
             ,
             therefore
             B
             G
             is
             14
             times
             lower
             than
             B
             O
             ;
             because
             Mercury
             is
             14
             times
             heavier
             than
             VVater
             .
             We
             see
             moreover
             ,
             that
             though
             two
             Cylinders
             of
             a
             Fluid
             ,
             can
             counterpoise
             one
             another
             in
             the
             
               Natural
               Ballance
            
             ,
             such
             as
             this
             Engine
             is
             ,
             yet
             they
             will
             not
             do
             it
             in
             the
             
               Artificial
               Ballance
            
             :
             because
             though
             B
             G
             counterpoise
             K
             I
             in
             this
             Ballance
             ,
             yet
             in
             a
             pair
             of
             Scales
             ,
             the
             Mercury
             will
             be
             as
             heavy
             again
             as
             the
             VVater
             .
             We
             see
             lastly
             ,
             that
             notwithstanding
             of
             this
             ,
             yet
             such
             a
             thing
             may
             be
             ;
             for
             if
             the
             orifice
             I
             ,
             were
             made
             as
             wide
             as
             the
             orifice
             F
             ,
             that
             the
             Cylinder
             K
             I
             might
             be
             equal
             to
             the
             Mercury
             B
             G
             in
             thickness
             ,
             then
             surely
             the
             one
             would
             counterpoise
             the
             other
             in
             the
             Libra
             or
             
               Artificial
               Ballance
            
             .
          
        
         
           
           
             EXPERIMENT
             XV.
             Figure
             21.
             
          
           
             THis
             Schematism
             represents
             a
             Water
             72
             foot
             deep
             ,
             as
             C
             D
             A
             B
             ,
             together
             with
             a
             crooked
             Pipe
             of
             glass
             I
             N
             H
             ,
             the
             one
             half
             whereof
             is
             I
             P
             ,
             56
             inches
             high
             ,
             and
             one
             inch
             wide
             ,
             the
             other
             half
             is
             P
             N
             R
             H
             ,
             of
             a
             far
             narrower
             diameter
             ,
             with
             an
             orifice
             H.
             There
             is
             also
             an
             orifice
             at
             L
             ,
             with
             a
             neck
             ,
             about
             which
             is
             knit
             a
             small
             chord
             M
             L
             ,
             for
             letting
             down
             this
             Engine
             to
             the
             bottom
             of
             the
             VVater
             A
             B.
             For
             trials
             cause
             ,
             fill
             the
             wide
             glass
             with
             Mercury
             from
             P
             to
             K
             ,
             and
             you
             will
             find
             it
             rise
             in
             the
             narrow
             Pipe
             ,
             as
             high
             as
             the
             orifice
             H.
             This
             being
             done
             ,
             close
             hermetically
             ,
             or
             with
             good
             cement
             the
             orifice
             L
             ;
             then
             by
             help
             of
             this
             chord
             ,
             let
             all
             go
             down
             from
             the
             surface
             C
             D
             ,
             till
             it
             be
             exactly
             17
             foot
             from
             the
             top
             ,
             and
             you
             will
             find
             the
             Mercury
             thrust
             down
             in
             the
             narrow
             Pipe
             ,
             from
             H
             to
             R
             ,
             14
             inches
             and
             an
             half
             .
             Let
             it
             down
             next
             ,
             as
             much
             ,
             and
             the
             Mercury
             will
             be
             yet
             further
             thrust
             down
             ,
             namely
             from
             R
             to
             N
             ,
             the
             part
             H
             R
             N
             being
             full
             of
             Water
             .
             For
             understanding
             the
             reason
             of
             this
             ,
             consider
             that
             between
             N
             and
             E
             ,
             are
             34
             foot
             :
             for
             so
             high
             is
             the
             slender
             Pillar
             of
             Water
             ,
             that
             comes
             from
             the
             top
             ,
             and
             entring
             the
             orifice
             H
             ,
             comes
             down
             thorow
             the
             Pipe
             to
             N.
             Consider
             next
             ,
             that
             between
             the
             said
             Pillar
             of
             Water
             ,
             and
             the
             Mercury
             N
             P
             K
             ,
             there
             is
             a
             counterpoise
             :
             but
             this
             counterpoise
             cannot
             be
             ,
             unless
             the
             Pillar
             of
             Water
             be
             34
             foot
             high
             ,
             seing
             between
             N
             and
             K
             are
             29
             inches
             of
             Mercury
             ;
             for
             each
             inch
             thereof
             requires
             14
             of
             Water
             .
             Upon
             this
             account
             it
             is
             ,
             that
             when
             the
             glass
             is
             17
             foot
             drowned
             ,
             14
             inches
             and
             an
             half
             are
             thrust
             down
             from
             H
             to
             R.
             If
             it
             be
             objected
             ,
             that
             the
             Pressure
             and
             Bensil
             of
             the
             inclosed
             Air
             
             I
             K
             ;
             is
             equivalent
             to
             the
             weight
             of
             other
             29
             inches
             ;
             and
             therefore
             the
             Pillar
             of
             Water
             E
             H
             R
             N
             ,
             must
             be
             68
             foot
             high
             ,
             before
             a
             counterpoise
             can
             happen
             .
             I
             answer
             ,
             't
             is
             true
             that
             's
             said
             ,
             but
             you
             do
             not
             consider
             ,
             that
             there
             is
             a
             Pillar
             of
             Air
             F
             E
             ,
             resting
             upon
             the
             top
             of
             the
             Pillar
             of
             Water
             ,
             that
             makes
             a
             compensation
             exactly
             .
             To
             speak
             then
             truely
             and
             really
             ,
             the
             29
             inches
             of
             Mercury
             N
             P
             K
             ,
             have
             the
             weight
             of
             58
             inches
             ;
             and
             the
             34
             foot
             of
             Water
             E
             H
             R
             N
             ,
             have
             the
             weight
             of
             68
             foot
             .
          
           
             For
             a
             third
             trial
             ,
             let
             down
             the
             glass
             6
             foot
             further
             ,
             and
             you
             will
             find
             the
             Water
             pierce
             up
             thorow
             the
             thick
             Cylinder
             of
             Mercury
             P
             K
             ,
             and
             rest
             upon
             the
             top
             K.
             The
             only
             difficulty
             is
             to
             determine
             ,
             how
             much
             will
             spring
             up
             before
             the
             motion
             of
             it
             cease
             ?
             'T
             is
             evident
             ,
             that
             the
             Water
             will
             ascend
             ,
             because
             coming
             to
             the
             Base
             of
             a
             thick
             and
             gross
             Cylinder
             ,
             that
             it
             cannot
             intirely
             lift
             ,
             it
             must
             pierce
             thorow
             it
             ,
             seing
             the
             force
             of
             such
             a
             Pillar
             of
             Water
             ,
             is
             now
             much
             stronger
             ,
             than
             the
             Mercury
             :
             for
             in
             effect
             ,
             the
             glass
             being
             drowned
             6
             foot
             further
             ,
             the
             Pillar
             that
             comes
             down
             thorow
             the
             slender
             Pipe
             ,
             hath
             the
             just
             weight
             of
             34
             inches
             of
             Mercury
             :
             but
             29
             cannot
             resist
             34
             :
             therefore
             the
             Water
             not
             being
             able
             to
             lift
             it
             ,
             by
             reason
             of
             the
             disproportion
             that
             's
             between
             the
             thickness
             of
             the
             one
             ,
             and
             the
             slenderness
             of
             the
             other
             ,
             it
             must
             pierce
             up
             thorow
             it
             .
             For
             clearing
             this
             difficulty
             ,
             consider
             ,
             that
             this
             glass
             cannot
             go
             down
             from
             one
             imaginary
             surface
             to
             another
             ,
             
               v.
               g.
            
             from
             34
             foot
             ,
             where
             it
             was
             ,
             till
             it
             come
             to
             40
             ,
             where
             it
             now
             stands
             ,
             but
             there
             must
             be
             an
             alteration
             in
             the
             equipondium
             ,
             seing
             by
             going
             down
             ,
             the
             Pillar
             of
             Water
             E
             H
             R
             N
             grows
             higher
             ,
             and
             consequently
             heavier
             ;
             and
             therefore
             ,
             some
             VVater
             must
             pierce
             up
             thorow
             the
             Mercury
             ,
             for
             making
             a
             counterpoise
             ;
             for
             't
             is
             impossible
             for
             two
             Fluids
             to
             counterpoise
             one
             another
             ,
             
             unless
             they
             be
             in
             equilibrio
             .
             Consider
             secondly
             ,
             that
             after
             the
             Water
             is
             come
             to
             the
             top
             of
             the
             Mercury
             at
             K
             ,
             it
             will
             find
             difficulty
             to
             find
             a
             room
             for
             it self
             ,
             seing
             the
             space
             between
             S
             and
             I
             is
             full
             of
             Air.
             Notwithstanding
             of
             this
             ,
             it
             must
             ascend
             .
             I
             say
             then
             ,
             after
             the
             glass
             is
             gone
             down
             from
             34
             ,
             to
             40
             foot
             ,
             there
             will
             be
             about
             four
             inches
             of
             VVater
             above
             K
             ,
             which
             have
             reduced
             the
             29
             inches
             of
             Air
             K
             I
             ,
             to
             25
             ,
             S
             I.
             
          
           
             If
             it
             be
             asked
             ,
             between
             what
             two
             things
             is
             the
             equipondium
             now
             ?
             I
             answer
             ,
             the
             first
             was
             at
             R
             ,
             between
             E
             H
             R
             ,
             and
             R
             N
             P
             K.
             The
             second
             was
             at
             R
             ,
             between
             N
             R
             H
             E
             ,
             and
             N
             P
             K.
             The
             third
             is
             now
             at
             S
             ,
             between
             the
             25
             inches
             of
             inclosed
             Air
             I
             S
             ,
             as
             one
             Antagonist
             ,
             and
             the
             four
             inches
             of
             Water
             S
             K
             ,
             with
             the
             29
             inches
             of
             Mercury
             K
             P
             ,
             and
             the
             Water
             P
             N
             R
             H
             E
             ,
             as
             the
             other
             .
             To
             make
             a
             fourth
             equipondium
             ,
             sink
             the
             Glass
             other
             six
             foot
             ,
             till
             it
             be
             46
             foot
             from
             the
             top
             C
             D
             ,
             then
             must
             some
             more
             VVater
             spring
             up
             thorow
             the
             Mercury
             ;
             this
             of
             necessity
             must
             be
             ,
             seing
             the
             Cylinder
             of
             VVater
             N
             R
             H
             E
             ,
             is
             six
             foot
             higher
             ,
             and
             so
             far
             heavier
             ,
             than
             it
             was
             :
             if
             this
             be
             ,
             then
             must
             the
             25
             inches
             of
             Air
             I
             S
             ,
             be
             reduced
             to
             less
             quantity
             ;
             seing
             'tis
             impossible
             ,
             for
             one
             Fluid
             to
             become
             heavier
             ,
             unless
             its
             opposite
             and
             antagonist
             become
             heavier
             too
             ,
             for
             an
             equipondiums
             sake
             .
             Note
             ,
             that
             the
             Air
             I
             S
             ,
             will
             not
             lose
             other
             four
             inches
             ,
             with
             this
             six
             foot
             of
             VVater
             ,
             as
             it
             did
             with
             the
             former
             .
             The
             reason
             is
             ,
             because
             ,
             if
             for
             every
             six
             foot
             the
             Glass
             goeth
             down
             ,
             the
             Air
             were
             comprest
             four
             inches
             ,
             it
             were
             easie
             at
             last
             to
             reduce
             it
             to
             nothing
             :
             for
             if
             six
             reduce
             it
             to
             four
             ,
             and
             12
             to
             eight
             ,
             38
             ought
             to
             reduce
             it
             to
             no
             inches
             ,
             which
             is
             impossible
             .
             Therefore
             I
             judge
             it
             must
             suffer
             compression
             ,
             by
             a
             certain
             proportion
             ,
             as
             we
             see
             upon
             a
             Scale
             ,
             the
             divisions
             of
             Artificial
             or
             
               Natural
               
               Sines
            
             grow
             less
             and
             less
             ,
             there
             being
             more
             space
             between
             1
             and
             2
             ,
             than
             between
             2
             and
             3
             ;
             more
             between
             2
             and
             3
             ,
             than
             between
             3
             and
             4
             ,
             and
             so
             upward
             till
             you
             come
             to
             90.
             
             Therefore
             the
             second
             six
             foot
             ,
             must
             reduce
             the
             25
             inches
             ,
             not
             to
             21
             ,
             but
             to
             23
             circiter
             ,
             and
             so
             forth
             .
             By
             the
             which
             means
             ,
             though
             the
             Glass
             should
             go
             down
             
               in
               infinitum
            
             ,
             yet
             the
             Air
             shall
             never
             be
             reduced
             to
             nothing
             ,
             and
             there
             shall
             still
             some
             small
             quantity
             of
             VVater
             come
             up
             .
             Or
             in
             such
             a
             case
             ,
             the
             Air
             may
             be
             so
             comprest
             ,
             that
             it
             can
             be
             no
             more
             ,
             all
             the
             
               disseminate
               vacuities
            
             being
             expelled
             .
             But
             suppose
             this
             to
             be
             at
             1000
             fathom
             ,
             then
             at
             1500
             ,
             where
             the
             Pressure
             is
             stronger
             ,
             there
             can
             be
             no
             equipondium
             ,
             which
             is
             absurd
             ,
             for
             where
             the
             pondus
             becomes
             stronger
             ,
             the
             potentia
             ought
             to
             grow
             stronger
             likewise
             .
             I
             answer
             ,
             the
             motion
             of
             condensation
             ceaseth
             indeed
             ;
             but
             there
             still
             remains
             a
             potentia
             ,
             or
             rather
             in
             such
             a
             case
             ,
             a
             perfect
             resistentia
             ,
             whereby
             the
             Air
             is
             able
             to
             resist
             the
             greatest
             weight
             imaginable
             ,
             before
             it
             can
             be
             reduced
             to
             nothing
             ,
             or
             suffer
             a
             penetration
             of
             parts
             ,
             that
             's
             to
             say
             ,
             two
             parts
             to
             be
             in
             one
             space
             .
          
           
             From
             the
             explication
             of
             these
             Phenomena
             we
             conclude
             first
             ,
             that
             in
             Water
             there
             is
             a
             considerable
             Pressure
             ,
             seing
             in
             letting
             down
             the
             Glass
             17
             foot
             ,
             the
             Mercury
             is
             prest
             down
             from
             H
             to
             R
             ,
             and
             from
             R
             to
             N
             ,
             in
             going
             down
             other
             17
             foot
             .
             Secondly
             ,
             that
             29
             inches
             of
             Mercury
             are
             as
             heavy
             as
             34
             foot
             of
             VVater
             :
             because
             the
             Mercury
             K
             P
             N
             makes
             a
             just
             equipondium
             with
             the
             VVater
             E
             H
             R
             N.
             Thirdly
             ,
             that
             Fluids
             not
             only
             of
             the
             same
             kind
             ,
             but
             of
             different
             kinds
             ,
             do
             counterpoise
             one
             another
             according
             to
             altitude
             ,
             and
             not
             according
             to
             thickness
             ;
             because
             though
             the
             Mercury
             K
             P
             N
             be
             far
             thicker
             ,
             than
             the
             VVater
             E
             H
             ,
             yet
             they
             counterballance
             one
             another
             ,
             because
             a
             proportion
             is
             kept
             according
             to
             their
             altitudes
             .
             Fourthly
             ,
             that
             a
             
             Fluid
             naturally
             lighter
             ,
             may
             move
             a
             Fluid
             naturally
             heavie●
             ,
             and
             thrust
             it
             out
             of
             its
             own
             place
             ,
             because
             the
             Water
             coming
             in
             at
             H
             ,
             thrusts
             down
             the
             Mercury
             to
             R
             ,
             and
             from
             R
             to
             N
             ,
             and
             so
             forth
             .
             Fifthly
             ,
             that
             of
             two
             F●uids
             unequal
             in
             strength
             ,
             debating
             together
             ,
             the
             weaker
             of
             necessity
             must
             yeeld
             to
             the
             stronger
             ,
             though
             the
             weaker
             be
             far
             heavier
             naturally
             than
             the
             stronger
             ,
             as
             is
             evident
             in
             the
             Mercu●y
             ,
             that
             yeelds
             to
             the
             Water
             .
             Sixthly
             ,
             that
             it
             is
             impossible
             for
             two
             Fluids
             ,
             so
             long
             as
             they
             are
             unequal
             in
             strength
             ,
             to
             cease
             from
             motion
             ,
             till
             they
             come
             to
             an
             equipondium
             ;
             because
             the
             Water
             alwayes
             springs
             up
             thorow
             the
             Mercury
             ,
             till
             an
             equal
             Ballance
             happen
             .
             Seventhly
             ,
             that
             one
             Fluid
             of
             this
             kind
             ,
             can
             counterpoise
             another
             Fluid
             of
             the
             same
             kind
             ,
             though
             there
             be
             divers
             Fluids
             interveening
             :
             because
             the
             Air
             F
             E
             ,
             counterpoiseth
             the
             Air
             I
             K
             ,
             or
             I
             S
             ,
             notwithstanding
             of
             Water
             and
             Mercury
             interveening
             .
             Eighthly
             ,
             that
             there
             may
             be
             as
             much
             Pressure
             in
             one
             inch
             of
             a
             Fluid
             ,
             as
             in
             a
             million
             ;
             because
             the
             29
             inches
             of
             Air
             I
             S
             ,
             have
             as
             much
             Bensil
             in
             them
             ,
             as
             is
             in
             the
             whole
             Pillar
             of
             Air
             E
             F
             ,
             that
             goeth
             up
             from
             the
             top
             of
             the
             VVater
             ,
             to
             the
             top
             of
             the
             Atmosphere
             .
             Ninthly
             ,
             that
             when
             one
             Fluid
             is
             under
             Pressure
             ,
             the
             next
             must
             be
             under
             the
             same
             degree
             of
             Pressure
             ,
             though
             they
             be
             not
             of
             the
             same
             kind
             ,
             but
             of
             different
             sorts
             ;
             because
             the
             Air
             I
             S
             ,
             the
             Water
             S
             K
             ,
             and
             Mercury
             K
             P
             ,
             are
             surely
             under
             the
             same
             degree
             of
             Pressure
             ;
             otherwise
             the
             motion
             could
             not
             end
             .
             Tenthly
             ,
             that
             when
             two
             Fluids
             of
             divers
             kinds
             do
             press
             one
             another
             ,
             that
             which
             is
             naturally
             lighter
             ,
             ascends
             alwayes
             to
             the
             higher
             place
             ,
             and
             the
             heavier
             to
             the
             lowest
             :
             because
             the
             Air
             I
             S
             ,
             is
             above
             the
             Water
             S
             K
             ,
             and
             the
             Water
             S
             K
             is
             above
             the
             Mercury
             .
             Note
             ,
             that
             this
             is
             not
             universal
             ,
             but
             only
             happens
             when
             the
             lighter
             Cylinder
             ,
             is
             slenderer
             than
             the
             other
             ,
             for
             if
             the
             
             Mercury
             K
             P
             ,
             were
             no
             thicker
             than
             the
             Water
             P
             N
             R
             H
             ,
             this
             would
             raise
             it
             intirely
             .
             Eleventhly
             ,
             that
             the
             compression
             of
             Air
             to
             less
             space
             ,
             is
             not
             according
             to
             
               Arithmetical
               progression
            
             ,
             1
             ,
             2
             ,
             3
             ,
             4
             ,
             5
             ,
             but
             according
             to
             some
             other
             proportion
             ,
             which
             may
             be
             called
             Uniform-difform
             .
             Note
             here
             ,
             that
             though
             this
             be
             true
             of
             the
             Air
             ,
             while
             it
             is
             comprest
             from
             a
             more
             quantity
             to
             a
             less
             ,
             as
             here
             ,
             or
             in
             a
             Wind-Gun
             ;
             yet
             it
             is
             not
             true
             of
             the
             Pressure
             of
             the
             Element
             of
             Air
             ,
             which
             is
             more
             and
             more
             from
             the
             top
             of
             the
             Atmosphere
             to
             the
             Earth
             ,
             according
             to
             
               Arithmetical
               Progression
            
             ,
             as
             in
             Water
             .
             We
             see
             lastly
             ,
             that
             the
             heaviest
             of
             Fluids
             ,
             such
             as
             Mercury
             ,
             press
             upward
             ,
             as
             well
             as
             downward
             ;
             because
             the
             top
             of
             the
             Mercury
             K
             ,
             thrusts
             up
             the
             Water
             K
             S
             ,
             as
             well
             as
             it
             thrusts
             down
             the
             Water
             P
             N
             R
             H.
             It
             may
             be
             enquired
             here
             ,
             how
             far
             this
             Glass
             would
             go
             down
             ,
             before
             the
             29
             inches
             of
             Air
             I
             K
             were
             reduced
             to
             one
             inch
             ?
             I
             answer
             ,
             its
             hard
             to
             determine
             ;
             but
             it
             seems
             it
             ought
             to
             go
             down
             more
             than
             300
             fathom
             .
             In
             this
             case
             ,
             there
             would
             be
             28
             inches
             of
             Water
             above
             K.
             Let
             us
             suppose
             the
             orifice
             H
             to
             be
             stopped
             at
             that
             deepness
             ,
             and
             the
             Glass
             brought
             above
             the
             Water
             ;
             then
             ,
             when
             the
             said
             orifice
             is
             opened
             in
             the
             Air
             ,
             you
             will
             find
             the
             whole
             VVater
             P
             N
             R
             H
             thrust
             out
             :
             and
             not
             only
             this
             ,
             but
             the
             whole
             Mercury
             P
             K
             ,
             spring
             out
             at
             the
             orifice
             H
             likewise
             ,
             except
             a
             little
             that
             remains
             between
             N
             and
             H
             :
             the
             reason
             is
             ,
             because
             the
             29
             inches
             of
             Air
             ,
             being
             reduced
             to
             one
             ,
             would
             be
             under
             a
             very
             great
             Bensil
             ;
             therefore
             the
             weight
             being
             taken
             away
             that
             begat
             it
             ,
             of
             its
             own
             accord
             ,
             it
             would
             expand
             it self
             to
             its
             old
             dimensions
             ;
             which
             it
             could
             not
             do
             ,
             unless
             both
             the
             28
             inches
             of
             VVater
             ,
             that
             's
             supposed
             to
             be
             above
             K
             ,
             and
             the
             Mercury
             K
             P
             were
             thrust
             out
             of
             their
             places
             .
          
        
         
           
           
             EXPERIMENT
             XVI
             .
             Figure
             22.
             
          
           
             THis
             Schematism
             represents
             a
             vessel
             full
             of
             VVater
             84
             inches
             deep
             ,
             namely
             from
             L
             N
             the
             first
             surface
             ,
             to
             M
             R
             the
             bottom
             .
             From
             M
             to
             R
             in
             breadth
             are
             20
             inches
             .
             There
             are
             here
             also
             two
             Glass-Pipes
             open
             at
             both
             ends
             ;
             the
             one
             ,
             two
             inches
             wide
             ,
             the
             other
             half
             an
             inch
             wide
             .
             Both
             of
             them
             are
             85
             inches
             long
             .
             X
             Y
             O
             is
             a
             surface
             of
             stagnant
             Mercury
             ,
             among
             which
             the
             two
             ends
             of
             the
             Pipes
             are
             drowned
             .
             E
             C
             is
             a
             Pillar
             of
             Mercury
             six
             inches
             in
             height
             ,
             and
             so
             is
             G
             D
             ,
             both
             of
             them
             raised
             to
             that
             altitude
             ,
             by
             the
             Pressure
             of
             the
             Water
             upon
             the
             surface
             X
             Y
             O.
             The
             Pillar
             E
             C
             A
             is
             supported
             by
             ,
             and
             rests
             upon
             ,
             the
             imaginary
             Pillar
             A
             P.
             And
             so
             is
             the
             Pillar
             G
             D
             B
             ,
             supported
             by
             the
             Pillar
             B
             Q.
             There
             are
             three
             things
             that
             occurres
             here
             from
             this
             operation
             of
             nature
             to
             be
             enquired
             after
             .
             First
             ,
             why
             ought
             the
             Mercury
             to
             rise
             in
             the
             two
             Tubs
             ,
             after
             the
             Vessel
             is
             filled
             with
             Water
             ?
             Secondly
             ,
             why
             rather
             six
             inches
             ,
             then
             seven
             or
             eight
             ?
             Thirdly
             ,
             what
             's
             the
             reason
             ,
             why
             it
             rises
             as
             high
             in
             the
             wide
             T●b
             ,
             as
             in
             the
             narrow
             ?
             I
             answer
             ,
             the
             Mercury
             rises
             from
             C
             to
             E
             ,
             and
             from
             D
             to
             G
             ,
             by
             the
             Pressure
             of
             the
             Water
             ,
             that
             rests
             upon
             the
             surface
             X
             Y
             O.
             Before
             that
             the
             Water
             is
             poured
             into
             the
             Vessel
             ,
             there
             is
             here
             a
             most
             equal
             and
             uniform
             Pressure
             upon
             the
             surface
             X
             Y
             O
             ,
             both
             without
             and
             within
             the
             Tub
             ,
             namely
             from
             the
             Air
             that
             rests
             upon
             it
             .
             But
             no
             sooner
             is
             the
             Water
             poured
             in
             ,
             but
             as
             soon
             the
             Pressure
             becomes
             unequal
             ;
             the
             parts
             of
             the
             surface
             without
             the
             Tub
             ,
             being
             more
             burdened
             ,
             then
             the
             parts
             C
             and
             D
             within
             .
             Therefore
             ,
             the
             part
             that
             's
             
             
             
             
             
             less
             prest
             ,
             must
             rise
             and
             climb
             up
             ,
             till
             the
             Pressure
             become
             equal
             :
             for
             it
             's
             impossible
             that
             a
             Fluid
             can
             cease
             from
             motion
             ,
             so
             long
             as
             there
             is
             inequality
             of
             weight
             between
             the
             pondus
             and
             the
             potentia
             .
             If
             any
             doubt
             ,
             let
             him
             pie●ce
             the
             side
             of
             the
             Vessel
             ,
             and
             when
             the
             whole
             Water
             is
             run
             out
             ,
             he
             will
             find
             E
             C
             and
             G
             D
             to
             have
             fallen
             down
             ,
             which
             clearly
             proves
             the
             climbing
             up
             of
             the
             Mercury
             ,
             to
             depend
             upon
             the
             in-pouring
             of
             the
             Water
             .
             For
             understanding
             the
             reason
             of
             the
             second
             ,
             remember
             that
             Mercury
             (
             as
             we
             have
             often
             noted
             )
             is
             counted
             14
             times
             heavier
             then
             Water
             ;
             therefore
             E
             C
             must
             be
             six
             inches
             ,
             seing
             X
             Y
             O
             is
             prest
             with
             the
             altitude
             of
             84
             inches
             of
             Water
             .
             It
             would
             be
             judged
             no
             marvel
             ,
             to
             see
             the
             Mercury
             rise
             from
             C
             to
             E
             ,
             and
             from
             D
             to
             G
             ,
             provided
             the
             face
             of
             the
             stagnant
             Mercury
             were
             as
             high
             as
             Z
             F.
             No
             more
             strange
             it
             is
             ,
             to
             see
             the
             two
             Mercuries
             rise
             ,
             with
             the
             Pressure
             of
             the
             Water
             ;
             for
             in
             effect
             and
             really
             ,
             the
             said
             Water
             is
             the
             just
             weight
             of
             as
             much
             Mercury
             as
             would
             fill
             between
             X
             O
             and
             Z
             F.
             For
             understanding
             the
             third
             ,
             remember
             (
             as
             was
             noted
             before
             )
             that
             Fluid
             Bodies
             counterpoise
             one
             another
             ,
             only
             according
             to
             altitude
             :
             therefore
             't
             is
             no
             matter
             ,
             whether
             the
             Tubs
             be
             wide
             or
             narrow
             .
             If
             it
             be
             enquired
             ,
             how
             can
             one
             and
             the
             ●ame
             Water
             ,
             counterpoise
             two
             Fluids
             of
             different
             weights
             ?
             To
             say
             ,
             that
             Fluids
             counterpoise
             one
             another
             according
             to
             altitude
             ,
             doth
             not
             clear
             the
             difficulty
             ;
             for
             it
             still
             remains
             to
             be
             asked
             ,
             why
             they
             counterpoise
             one
             another
             after
             this
             manner
             ?
             Therefore
             it
             seems
             ,
             that
             if
             the
             Water
             raise
             the
             Mercury
             from
             C
             to
             E
             in
             the
             wide
             Pipe
             ,
             it
             must
             raise
             it
             in
             the
             narrow
             one
             from
             D
             to
             K.
             For
             answer
             ,
             consider
             first
             ,
             that
             as
             there
             are
             here
             two
             Pillars
             of
             Mercury
             C
             E
             ,
             and
             D
             G
             within
             the
             two
             Tubs
             ,
             so
             there
             are
             here
             also
             two
             Pillars
             of
             Mercury
             A
             P
             and
             B
             Q
             ,
             under
             
             the
             two
             orifices
             ,
             upon
             which
             the
             said
             two
             Pillars
             stand
             ,
             and
             rest
             .
             Consider
             secondly
             ,
             that
             the
             Potentia
             or
             force
             of
             the
             Pillar
             A
             P
             ,
             is
             just
             equal
             to
             the
             Pondus
             of
             the
             Pillar
             E
             C
             A
             :
             Item
             ,
             that
             the
             Potentia
             of
             the
             Pillar
             B
             Q
             ,
             is
             equal
             to
             the
             Pondus
             G
             D
             B.
             Thirdly
             ,
             that
             the
             Potentia
             of
             A
             P.
             is
             most
             exactly
             equal
             to
             the
             Potentia
             of
             B
             Q
             ;
             and
             the
             reason
             is
             ,
             because
             their
             tops
             A
             and
             B
             ,
             are
             parts
             of
             the
             same
             horizontal
             surface
             .
             I
             say
             then
             ,
             if
             A
             P
             be
             equal
             to
             E
             C
             A
             ,
             and
             B
             Q
             equal
             to
             G
             D
             B
             ,
             and
             A
             P
             ,
             and
             B
             Q
             ,
             equal
             among
             themselves
             ,
             then
             must
             E
             C
             A
             be
             equal
             to
             G
             D
             B.
             The
             same
             Water
             then
             ,
             doth
             not
             counterpoise
             two
             Bodies
             of
             different
             weight
             .
             I
             grant
             E
             C
             A
             to
             be
             far
             heavier
             ,
             than
             G
             D
             B
             ,
             while
             they
             are
             weighed
             in
             a
             pair
             of
             scales
             ,
             but
             the
             one
             is
             not
             heavier
             than
             the
             other
             ,
             as
             they
             are
             weighed
             in
             this
             ballance
             of
             nature
             .
          
           
             From
             what
             is
             said
             ,
             we
             see
             first
             ,
             that
             in
             VVater
             there
             is
             a
             Pressure
             ,
             and
             a
             considerable
             weight
             .
             This
             is
             evident
             from
             the
             rising
             of
             the
             Mercury
             .
             VVe
             see
             secondly
             ,
             that
             Fluids
             counterpoise
             one
             another
             ,
             only
             according
             to
             Altitude
             .
             Thirdly
             ,
             that
             when
             a
             lighter
             Fluid
             presseth
             up
             a
             heavier
             ,
             there
             is
             no
             more
             prest
             up
             of
             it
             ,
             than
             is
             the
             just
             weight
             of
             the
             pressing
             Fluid
             ,
             because
             the
             Mercury
             E
             C
             ,
             is
             just
             the
             weight
             of
             the
             VVater
             that
             presseth
             upon
             X
             Y
             O.
             That
             's
             to
             say
             ,
             the
             part
             of
             the
             surface
             C
             ,
             is
             no
             more
             prest
             with
             the
             Mercury
             E
             C
             ,
             than
             the
             part
             X
             ,
             is
             prest
             with
             the
             VVater
             L
             Z
             X.
             Fourthly
             ,
             if
             Mercury
             were
             28
             times
             heavier
             than
             VVater
             ,
             only
             three
             inches
             would
             be
             prest
             up
             :
             if
             it
             were
             but
             seven
             times
             heavier
             ,
             the
             altitude
             would
             be
             at
             S
             ,
             12
             inches
             above
             C.
             Fifthly
             ,
             it
             's
             as
             easie
             for
             a
             large
             part
             of
             a
             surface
             ,
             to
             sustain
             a
             large
             Pillar
             ,
             as
             't
             is
             for
             a
             narrow
             part
             ,
             to
             sustain
             a
             narrower
             Pillar
             :
             because
             A
             P
             sustains
             E
             C
             A
             ,
             as
             easily
             ,
             as
             B
             Q
             sustains
             G
             D
             B.
             
             Sixthly
             ,
             that
             in
             Fluids
             there
             is
             a
             pondus
             and
             a
             potentia
             :
             as
             is
             clear
             from
             the
             potentia
             of
             A
             P
             ,
             that
             sustains
             the
             pondus
             of
             E
             C
             A.
             The
             VVater
             likewise
             that
             sustains
             ,
             hath
             a
             potentia
             ,
             and
             the
             Mercury
             E
             C
             is
             the
             pondus
             of
             it
             .
             Seventhly
             ,
             that
             there
             is
             alwayes
             equality
             of
             weight
             between
             the
             pondus
             and
             the
             potentia
             .
             So
             is
             the
             potentia
             of
             A
             P
             ,
             equal
             to
             the
             pondus
             E
             C
             A.
             Eighthly
             ,
             that
             the
             pondus
             begets
             the
             potentia
             .
             So
             the
             weight
             of
             the
             VVater
             ,
             begets
             the
             potentia
             that's
             in
             A
             P.
             For
             make
             this
             VVater
             deeper
             ,
             and
             you
             augment
             the
             potentia
             of
             A
             P.
             If
             you
             subtract
             from
             it
             ,
             the
             potentia
             of
             A
             P
             grows
             less
             by
             proportion
             .
             Or
             the
             weight
             of
             E
             C
             A
             ,
             may
             be
             said
             to
             beget
             the
             potentia
             of
             A
             P.
             To
             proceed
             a
             little
             further
             ,
             let
             us
             suppose
             the
             Air
             H
             E
             to
             be
             removed
             .
             In
             this
             case
             ,
             the
             Mercury
             rises
             29
             inches
             higher
             than
             E
             ,
             or
             35
             above
             C
             ;
             even
             as
             high
             as
             S.
             In
             the
             narrow
             Tub
             it
             will
             climb
             up
             to
             K
             ,
             if
             you
             take
             away
             the
             Air
             I
             G.
             This
             comes
             to
             pass
             ,
             by
             vertue
             of
             the
             Pressure
             of
             the
             Atmosphere
             ,
             that
             rests
             upon
             L
             N.
             From
             this
             we
             gather
             ninthly
             ,
             that
             there
             is
             a
             counterpoise
             between
             the
             Air
             H
             E
             ,
             and
             the
             weight
             of
             the
             Air
             that
             rests
             upon
             L
             N
             ;
             and
             that
             a
             slender
             Pillar
             of
             Air
             ,
             is
             able
             to
             counterpoise
             a
             thicker
             :
             for
             H
             E
             is
             far
             narrower
             than
             L
             N.
             Tenthly
             ,
             that
             the
             Pressure
             of
             the
             Air
             ,
             can
             be
             communicated
             thorow
             divers
             kinds
             of
             Fluids
             ;
             because
             the
             weight
             that
             rests
             upon
             L
             N
             ,
             is
             sent
             down
             thorow
             the
             VVater
             L
             Z
             X
             ,
             and
             down
             thorow
             the
             stagnant
             Mercury
             ,
             and
             thrusts
             up
             the
             Liquor
             from
             A
             to
             S
             ,
             35
             inches
             .
             Eleventhly
             ,
             that
             a
             lighter
             Fluid
             may
             be
             made
             to
             press
             with
             greater
             burden
             ,
             than
             a
             Fluid
             naturally
             heavier
             ;
             because
             the
             weight
             of
             the
             Air
             upon
             L
             N
             ,
             raises
             29
             inches
             of
             Mercury
             ,
             but
             the
             VVater
             raises
             only
             six
             .
             VVe
             see
             twelfthly
             ,
             that
             Fluids
             have
             a
             sphere
             of
             activity
             ,
             to
             which
             they
             are
             able
             to
             
             press
             up
             themselves
             ,
             or
             Fluids
             of
             different
             kinds
             :
             because
             first
             ,
             the
             stagnant
             Mercury
             can
             raise
             it self
             no
             higher
             within
             the
             Pipe
             ,
             than
             it
             is
             without
             .
             Next
             ,
             the
             84
             inches
             of
             Water
             ,
             can
             raise
             the
             Mercury
             no
             higher
             than
             E.
             Lastly
             ,
             the
             weight
             of
             the
             Atmosphere
             ,
             can
             raise
             the
             Mercury
             no
             higher
             than
             S
             ,
             29
             inches
             above
             E.
             
          
           
             For
             another
             trial
             ,
             take
             out
             from
             among
             the
             Water
             ,
             the
             two
             Pipes
             ,
             and
             stopping
             closely
             the
             two
             under
             orifices
             ,
             fill
             them
             with
             Mercury
             to
             the
             brim
             .
             Then
             thrust
             them
             down
             as
             before
             ,
             and
             open
             the
             said
             two
             orifices
             ,
             while
             they
             are
             below
             the
             surface
             X
             Y
             O
             ,
             and
             you
             will
             find
             the
             whole
             Cylinder
             fall
             down
             from
             H
             to
             E
             ,
             and
             there
             halt
             :
             and
             the
             whole
             Cylinder
             in
             the
             narrow
             Pipe
             falls
             down
             from
             I
             to
             G.
             Or
             ,
             if
             you
             please
             ,
             before
             this
             be
             done
             ,
             stop
             closely
             the
             orifice
             H
             ,
             and
             the
             orifice
             I
             ,
             and
             you
             will
             find
             the
             Mercury
             go
             no
             further
             down
             than
             S
             ,
             by
             opening
             the
             orifice
             A
             ;
             and
             no
             further
             down
             than
             K
             ,
             by
             opening
             the
             orifice
             B.
             This
             leads
             us
             to
             a
             clear
             discovery
             of
             the
             reason
             ,
             why
             the
             Mercury
             subsides
             ,
             and
             sinks
             down
             from
             the
             top
             of
             the
             Tub
             in
             the
             Baroscope
             ,
             to
             the
             29th
             inch
             ,
             whatever
             the
             diameter
             of
             the
             Pipe
             be
             .
             And
             this
             lets
             us
             see
             ,
             that
             the
             Mercurial
             Cylinder
             is
             suspended
             by
             the
             Air
             ,
             after
             the
             same
             manner
             ,
             that
             the
             Mercury
             E
             C
             is
             suspended
             after
             :
             and
             that
             there
             is
             no
             more
             difficulty
             in
             the
             one
             ,
             than
             in
             the
             other
             .
          
        
         
           
             EXPERIMENT
             XVII
             .
             Figure
             23
             ,
             24.
             
          
           
             THis
             Schematism
             represents
             a
             Water
             30
             fathom
             deep
             .
             Under
             the
             first
             surface
             A
             ,
             there
             are
             six
             imaginary
             ,
             as
             B
             C
             D
             E
             F
             G
             ,
             every
             one
             whereof
             ,
             is
             five
             fathom
             below
             
             another
             .
             There
             are
             here
             likewise
             two
             Glasses
             ,
             each
             one
             12
             inches
             high
             ,
             and
             5
             inches
             broad
             ,
             like
             unto
             these
             ,
             wherein
             Wine
             ,
             Sack
             ,
             or
             Brandy
             is
             preserved
             .
             The
             Glass
             G
             M
             hath
             its
             orifice
             G
             upward
             .
             The
             other
             Glass
             is
             compleatly
             open
             below
             ,
             without
             a
             narrow
             orifice
             .
             For
             making
             Experiment
             ,
             take
             a
             long
             chord
             ,
             as
             long
             as
             the
             Water
             is
             in
             deepness
             ,
             and
             knit
             the
             end
             of
             it
             round
             about
             the
             neck
             of
             the
             Glass
             at
             G.
             Take
             another
             line
             of
             the
             same
             length
             ,
             and
             fasten
             it
             to
             the
             bottom
             of
             the
             other
             Glass
             at
             L.
             Next
             ,
             for
             sinking
             the
             two
             Glasses
             ,
             take
             two
             weights
             of
             Lead
             ,
             and
             fasten
             the
             one
             to
             the
             bottom
             at
             M
             ,
             and
             the
             other
             to
             the
             open
             part
             of
             the
             Glass
             at
             S
             ,
             and
             T.
             The
             two
             weights
             then
             ,
             are
             P
             and
             Q
             ,
             each
             one
             of
             them
             about
             10
             or
             12
             pound
             weight
             .
             These
             things
             being
             done
             ,
             let
             first
             down
             the
             Glass
             G
             M
             ,
             till
             the
             weight
             Q
             sink
             it
             five
             fathom
             ,
             namely
             from
             A
             to
             B
             ,
             and
             if
             you
             pull
             it
             up
             ,
             you
             will
             find
             the
             bottom
             covered
             with
             Water
             ,
             from
             M
             to
             I
             ,
             about
             four
             or
             five
             inches
             .
             Let
             it
             down
             next
             ,
             from
             A
             to
             C
             ,
             ten
             fathom
             ,
             and
             you
             will
             find
             more
             Water
             in
             it
             ;
             even
             as
             much
             as
             fills
             it
             from
             M
             to
             2
             ,
             about
             seven
             or
             eight
             inches
             .
             In
             passing
             from
             C
             D
             ,
             the
             Water
             rises
             from
             2
             to
             3.
             
             If
             you
             sink
             it
             ,
             from
             D
             to
             E
             ,
             the
             VVater
             rises
             from
             3
             to
             4.
             
             The
             VVater
             rises
             from
             4
             to
             5
             ,
             when
             the
             glass
             is
             come
             the
             length
             of
             F.
             And
             lastly
             ,
             when
             the
             Glass
             is
             at
             G
             ,
             the
             lowest
             fathom
             ,
             the
             VVater
             is
             as
             high
             as
             K.
             Let
             down
             next
             ,
             the
             other
             Glass
             from
             A
             to
             B
             ,
             and
             you
             will
             find
             the
             Water
             rise
             in
             it
             from
             H
             to
             I
             ,
             four
             or
             five
             inches
             ,
             as
             in
             the
             other
             Glass
             .
             In
             going
             down
             from
             B
             to
             C
             ,
             it
             rises
             from
             1
             to
             2.
             
             From
             C
             to
             D
             ,
             it
             rises
             from
             2
             to
             3.
             
             From
             D
             to
             E
             ,
             it
             rises
             from
             3
             to
             4
             ,
             and
             so
             forward
             ,
             till
             the
             Glass
             come
             to
             the
             lowest
             fathom
             ,
             where
             the
             Water
             rises
             as
             high
             as
             I.
             
          
           
           
             There
             are
             here
             several
             Phenomena
             to
             be
             considered
             .
             First
             ,
             that
             the
             Water
             creeps
             in
             at
             the
             orifice
             G
             ,
             and
             fills
             the
             under
             part
             of
             the
             Glass
             from
             M
             to
             K.
             Secondly
             ,
             that
             
               not
               one
               particle
            
             of
             Air
             comes
             out
             ,
             all
             the
             time
             the
             VVater
             is
             in
             going
             in
             .
             Thirdly
             ,
             that
             this
             Air
             is
             comprest
             from
             M
             to
             K
             ,
             nine
             inches
             .
             Lastly
             ,
             that
             the
             ingress
             of
             the
             Water
             ,
             is
             according
             to
             
               unequal
               proportion
            
             :
             because
             while
             the
             Glass
             passeth
             from
             A
             to
             B
             ,
             more
             VVater
             creeps
             in
             at
             G
             ,
             and
             fills
             the
             bottom
             ,
             then
             in
             passing
             from
             B
             to
             C.
             And
             more
             in
             going
             down
             from
             B
             to
             G
             ,
             than
             in
             going
             down
             from
             C
             to
             D
             ,
             as
             is
             clear
             from
             the
             unequal
             divisions
             1
             ,
             2
             ,
             3
             ,
             4
             ,
             5
             ,
             6
             ,
             For
             understanding
             the
             reason
             of
             the
             first
             ,
             remember
             that
             in
             this
             deep
             Water
             ,
             there
             is
             a
             Pressure
             ,
             and
             that
             this
             Pressure
             grows
             ,
             as
             the
             VVater
             grows
             in
             deepness
             .
             It
             is
             then
             by
             vertue
             of
             this
             ,
             that
             the
             VVater
             creeps
             in
             ,
             and
             fills
             the
             bottom
             of
             the
             Vessel
             :
             for
             in
             effect
             ,
             every
             part
             being
             under
             a
             burden
             ,
             and
             being
             therefore
             desirous
             to
             liberat
             themselves
             from
             it
             ,
             they
             take
             occasion
             to
             thrust
             in
             themselves
             ,
             finding
             ,
             as
             it
             were
             ,
             more
             ease
             here
             ,
             than
             without
             ,
             the
             Air
             within
             the
             Glass
             ,
             being
             under
             less
             Pressure
             ,
             than
             the
             VVater
             without
             .
             The
             second
             Phenomenon
             is
             caused
             by
             the
             straitness
             and
             narrowness
             of
             the
             hole
             G
             :
             for
             this
             entry
             being
             no
             wider
             ,
             than
             the
             thickness
             of
             a
             Sack-Needle
             ,
             the
             Air
             cannot
             go
             out
             ,
             while
             the
             VVater
             is
             coming
             in
             ;
             that
             is
             ,
             the
             passage
             is
             so
             strait
             ,
             that
             the
             one
             cannot
             go
             by
             the
             other
             .
             This
             leads
             us
             to
             the
             reason
             of
             the
             third
             ,
             for
             if
             not
             one
             particle
             of
             Air
             go
             out
             ,
             all
             the
             while
             the
             Glass
             is
             in
             going
             down
             ,
             then
             surely
             ,
             the
             VVater
             filling
             between
             M
             and
             K
             ,
             must
             compress
             the
             Air
             ,
             and
             reduce
             it
             from
             twelve
             inches
             to
             three
             .
             But
             the
             greater
             difficulty
             is
             ,
             why
             the
             ingress
             of
             the
             VVater
             is
             according
             to
             
               unequal
               proportion
            
             .
             For
             understanding
             this
             ,
             consider
             ,
             that
             this
             
             inequality
             ,
             is
             not
             caused
             by
             any
             unequal
             Pressure
             that
             's
             in
             the
             VVater
             ;
             for
             if
             this
             were
             true
             ,
             then
             there
             ought
             to
             be
             less
             Pressure
             in
             the
             surface
             F
             ,
             than
             in
             the
             surface
             E
             ,
             and
             less
             in
             E
             ,
             than
             in
             D
             ,
             which
             is
             false
             and
             absurd
             .
             This
             inequality
             then
             ,
             must
             flow
             from
             the
             nature
             of
             the
             Air
             it self
             ,
             that
             naturally
             suffers
             compression
             after
             such
             a
             manner
             .
             'T
             is
             evident
             from
             the
             compression
             of
             Air
             in
             Wind-guns
             ;
             for
             less
             force
             is
             required
             to
             compress
             the
             first
             span
             ,
             than
             to
             compress
             the
             second
             :
             or
             contrariwise
             ,
             more
             strength
             is
             required
             ,
             to
             compress
             the
             third
             span
             ,
             than
             the
             second
             ;
             more
             to
             compress
             the
             fourth
             ,
             than
             the
             third
             ,
             and
             so
             forth
             .
             'T
             is
             evident
             in
             all
             bodies
             endowed
             with
             Bensil
             ,
             as
             in
             the
             Spring
             of
             a
             Watch
             ,
             that
             requires
             more
             strength
             to
             bend
             it
             .
             in
             the
             end
             ,
             than
             in
             the
             beginning
             .
          
           
             For
             a
             second
             trial
             ,
             pull
             up
             from
             the
             bottom
             of
             the
             Water
             the
             Glass
             L
             I
             H
             ,
             and
             when
             it
             comes
             above
             ,
             you
             will
             find
             nothing
             in
             it
             .
             The
             reason
             is
             ,
             because
             the
             Vessel
             being
             open
             between
             T
             and
             S
             ,
             the
             whole
             VVater
             I
             H
             ,
             falls
             down
             by
             degrees
             ;
             but
             in
             effect
             ,
             is
             really
             thrust
             out
             ,
             by
             the
             strong
             Bensil
             of
             the
             comprest
             Air
             I
             L
             ,
             that
             now
             expands
             it self
             ,
             when
             it
             finds
             the
             Glass
             go
             up
             thorow
             the
             VVater
             ,
             whose
             Pressure
             is
             less
             ,
             and
             less
             from
             the
             bottom
             to
             the
             top
             .
             but
             the
             contrary
             effect
             follows
             ,
             when
             the
             other
             Glass
             is
             pulled
             up
             ;
             namely
             ,
             the
             VVater
             remains
             within
             the
             Glass
             ,
             and
             the
             Air
             above
             it
             ,
             is
             thrust
             out
             by
             degrees
             ,
             as
             the
             Glass
             comes
             nearer
             to
             the
             top
             .
             For
             understanding
             the
             reason
             of
             this
             ,
             consider
             first
             ,
             that
             while
             the
             orifice
             G
             ,
             is
             level
             with
             the
             lowest
             surface
             ,
             where
             it
             now
             is
             ;
             that
             's
             supposed
             to
             be
             30
             fathom
             deep
             ,
             there
             is
             a
             real
             counterpoise
             between
             the
             inclosed
             Air
             G
             K
             ,
             and
             the
             ambient
             VVater
             without
             :
             for
             with
             what
             force
             the
             one
             strives
             to
             be
             in
             ,
             with
             the
             same
             force
             the
             other
             endeavours
             to
             be
             out
             ;
             and
             because
             they
             are
             in
             
             equal
             terms
             ,
             therefore
             the
             one
             cannot
             yeeld
             to
             the
             other
             .
             If
             you
             please
             to
             give
             the
             victory
             to
             the
             VVater
             ,
             then
             let
             the
             Glass
             go
             further
             down
             :
             but
             if
             you
             desire
             the
             Air
             to
             overcome
             ,
             then
             must
             the
             Glass
             be
             pulled
             up
             .
             Pull
             it
             then
             up
             from
             the
             place
             it
             is
             in
             ,
             till
             it
             come
             to
             F
             ,
             and
             you
             will
             find
             a
             considerable
             quantity
             of
             Air
             come
             out
             at
             G
             ,
             and
             after
             2
             or
             3
             minuts
             of
             time
             ,
             emerge
             and
             come
             to
             the
             top
             A
             ,
             in
             form
             of
             round
             Bells
             ,
             or
             Bubbles
             .
             The
             deepness
             and
             groseness
             of
             the
             Water
             thorow
             which
             the
             Bubbles
             come
             ,
             makes
             their
             motion
             so
             slow
             .
             The
             reason
             of
             this
             eruption
             ,
             must
             be
             less
             Pressure
             of
             Water
             in
             the
             surface
             F
             ,
             than
             in
             the
             lowest
             G
             ,
             from
             whence
             the
             Glass
             came
             .
             Suppose
             then
             ,
             the
             lowest
             to
             have
             six
             degrees
             of
             Pressure
             ,
             F
             to
             have
             five
             ,
             E
             to
             have
             four
             ,
             D
             three
             ,
             C
             two
             ,
             and
             B
             to
             have
             one
             :
             and
             supposing
             the
             inclosed
             Air
             K
             G
             ,
             to
             be
             equal
             in
             force
             to
             the
             Pressure
             of
             the
             lowest
             fathom
             ,
             it
             must
             then
             have
             six
             degrees
             of
             Bensil
             in
             it
             .
             Put
             the
             case
             then
             ,
             that
             with
             six
             degrees
             of
             Bensil
             ,
             it
             come
             to
             the
             surface
             F
             ,
             that
             hath
             but
             five
             ,
             it
             must
             surely
             break
             forth
             ,
             and
             overcome
             the
             force
             and
             power
             of
             that
             surface
             :
             for
             't
             is
             impossible
             that
             two
             Fluids
             can
             be
             unequal
             in
             force
             and
             power
             ,
             but
             the
             strongest
             must
             overcome
             ,
             and
             the
             weakest
             yeeld
             :
             therefore
             ,
             when
             the
             orifice
             comes
             to
             F
             ,
             the
             Air
             being
             stronger
             than
             the
             Water
             ,
             breaks
             forth
             ;
             and
             as
             long
             doth
             this
             eruption
             continue
             ,
             as
             inequality
             of
             power
             continues
             between
             the
             one
             and
             the
             other
             .
             In
             pulling
             up
             the
             Glass
             from
             F
             to
             E
             ,
             other
             five
             fathom
             ,
             more
             Air
             comes
             out
             .
             The
             reason
             is
             the
             same
             ,
             namely
             less
             Pressure
             in
             E
             than
             in
             F
             :
             therefore
             ,
             when
             the
             inclosed
             Air
             ,
             that
             hath
             five
             degrees
             of
             Bensil
             ,
             comes
             to
             E
             ,
             that
             hath
             but
             four
             ,
             it
             must
             overcome
             ,
             and
             so
             long
             must
             it
             be
             victorious
             ,
             till
             by
             expanding
             it self
             ,
             it
             be
             reduced
             to
             the
             Bensil
             of
             four
             .
             In
             pulling
             up
             the
             Glass
             from
             E
             to
             D
             ,
             more
             Air
             yet
             breaks
             
             out
             ,
             because
             a
             surface
             of
             three
             degrees
             of
             Pressure
             ,
             is
             not
             able
             to
             resist
             four
             degrees
             of
             Bensil
             .
             In
             passing
             from
             D
             to
             C
             ,
             more
             Air
             comes
             yet
             out
             for
             the
             same
             reason
             ,
             till
             in
             going
             up
             to
             the
             top
             ,
             where
             there
             is
             no
             Pressure
             ,
             no
             more
             Air
             breaks
             out
             .
          
           
             'T
             is
             to
             be
             observed
             first
             ,
             that
             the
             motion
             of
             the
             Air
             up
             thorow
             the
             Water
             is
             but
             slow
             ,
             the
             medium
             being
             thick
             ,
             and
             gross
             .
             Secondly
             ,
             that
             if
             the
             Glass
             be
             pulled
             up
             quickly
             ,
             from
             one
             surface
             to
             another
             ,
             or
             contrariwise
             ,
             let
             down
             quickly
             ,
             it
             presently
             breaks
             in
             pieces
             .
             This
             comes
             to
             pass
             through
             the
             strong
             Bensil
             of
             the
             inclosed
             Air
             ,
             that
             must
             have
             time
             to
             expand
             it self
             ,
             otherwise
             it
             breaks
             out
             at
             the
             nearest
             :
             for
             it
             being
             of
             six
             degrees
             of
             Bensil
             ,
             and
             coming
             quickly
             to
             a
             surface
             of
             five
             ,
             there
             happens
             an
             unequal
             Pressure
             ,
             the
             sides
             of
             the
             Glass
             being
             thrust
             out
             ,
             with
             greater
             force
             ,
             than
             they
             are
             thrust
             in
             with
             .
             But
             if
             so
             be
             ,
             the
             Glass
             move
             slowly
             up
             ,
             the
             inclosed
             Air
             gets
             time
             to
             thrust
             it self
             out
             by
             degrees
             ,
             so
             that
             whatever
             surface
             the
             Glass
             comes
             to
             ,
             there
             is
             little
             difference
             between
             the
             Pressure
             of
             the
             Water
             ,
             and
             the
             Bensil
             of
             the
             Air.
             The
             reason
             why
             the
             Glass
             breaks
             in
             pieces
             ,
             while
             it
             goes
             quickly
             down
             ,
             is
             likewayes
             unequal
             Pressure
             upon
             the
             sides
             :
             for
             in
             passing
             quickly
             from
             a
             surface
             of
             five
             degrees
             ,
             to
             a
             surface
             of
             six
             ,
             the
             sides
             are
             prest
             in
             with
             greater
             force
             ,
             than
             they
             are
             prest
             out
             with
             ,
             and
             the
             reason
             is
             ,
             because
             through
             the
             straitness
             of
             the
             hole
             G
             ,
             the
             Water
             cannot
             win
             in
             soon
             enough
             ,
             to
             make
             as
             much
             Pressure
             within
             ,
             as
             there
             is
             without
             .
             'T
             is
             to
             be
             observed
             thirdly
             ;
             that
             if
             the
             orifice
             G
             be
             stopped
             ,
             before
             that
             the
             Glass
             be
             sent
             down
             ,
             it
             will
             not
             go
             beyond
             three
             or
             four
             fathom
             ,
             when
             it
             shall
             be
             broken
             in
             pieces
             ;
             though
             the
             motion
             were
             never
             so
             slow
             :
             and
             this
             comes
             to
             pass
             ,
             through
             the
             strong
             Pressure
             
             of
             the
             Water
             .
             Fourthly
             ,
             the
             stronger
             the
             Glass
             be
             in
             the
             sides
             ,
             it
             goes
             the
             further
             down
             without
             breaking
             :
             therefore
             a
             round
             
               Glass
               Bottle
            
             ,
             will
             sink
             20
             or
             30
             fathom
             ,
             before
             that
             it
             be
             broken
             with
             the
             Pressure
             of
             the
             Water
             .
             If
             a
             Vessel
             of
             iron
             were
             sent
             down
             ,
             it
             ought
             to
             go
             much
             further
             .
             An
             empty
             Cask
             ,
             or
             Hogsh●ad
             ,
             will
             not
             sink
             beyond
             seven
             or
             eight
             fathom
             ,
             without
             breaking
             ,
             or
             bursting
             ;
             yet
             a
             Bladder
             full
             of
             wind
             ,
             knit
             about
             the
             neck
             with
             a
             Pack-Threed
             ,
             will
             go
             down
             100
             fathom
             ,
             yea
             1000
             without
             bursting
             .
          
           
             It
             may
             be
             here
             inquired
             ,
             what
             sort
             of
             proportion
             is
             keeped
             by
             the
             
               unequal
               ingress
            
             of
             the
             Water
             ?
             I
             answer
             ,
             it
             may
             be
             known
             after
             this
             manner
             .
             Let
             first
             down
             the
             Glass
             one
             fathom
             ,
             and
             having
             pulled
             it
             up
             again
             ,
             measure
             the
             deepness
             of
             the
             Water
             in
             the
             bottom
             ,
             of
             it
             .
             Next
             ,
             having
             poured
             out
             that
             Water
             ,
             let
             it
             down
             two
             fathom
             ,
             and
             pulling
             it
             up
             ,
             measure
             the
             deepness
             ,
             which
             you
             will
             find
             more
             ,
             than
             afore
             .
             Do
             after
             this
             manner
             ,
             the
             third
             time
             ,
             and
             the
             fourth
             time
             ,
             till
             you
             come
             to
             the
             lowest
             fathom
             ,
             and
             you
             will
             find
             the
             true
             proportion
             .
          
           
             From
             what
             is
             said
             we
             see
             first
             ,
             that
             in
             Water
             there
             is
             a
             Pressure
             ,
             because
             through
             the
             force
             and
             power
             of
             this
             Water
             ,
             the
             12
             inches
             of
             Air
             that
             filled
             the
             Glass
             ,
             are
             reduced
             to
             three
             .
             Secondly
             ,
             that
             this
             Pressure
             growes
             ,
             as
             the
             Water
             growes
             in
             deepness
             :
             because
             there
             is
             more
             Pressure
             in
             B
             ,
             than
             in
             A
             ,
             more
             in
             C
             ,
             than
             in
             B
             ;
             and
             Io
             downward
             .
             Thirdly
             ,
             that
             when
             Air
             is
             comprest
             ,
             by
             some
             extrinseck
             weight
             ,
             the
             Bensil
             is
             intended
             ,
             and
             grows
             stronger
             by
             
               unequal
               proportion
            
             ,
             as
             is
             clear
             from
             the
             unequal
             divisions
             ,
             1
             ,
             2
             ,
             2
             ,
             4
             ,
             5
             ,
             6.
             
             Fourthly
             ,
             two
             Fluids
             cannot
             cease
             from
             motion
             ,
             so
             long
             as
             the
             potentia
             of
             the
             one
             ,
             is
             unequal
             to
             the
             po●d●s
             of
             the
             other
             :
             this
             is
             evident
             
             from
             the
             Water
             's
             creeping
             in
             at
             G
             ,
             all
             the
             while
             the
             Glass
             is
             in
             going
             down
             ;
             and
             from
             the
             Air
             's
             coming
             out
             ,
             all
             the
             while
             the
             Glass
             is
             in
             coming
             up
             .
             Fifthly
             ,
             that
             no
             sooner
             two
             Fluids
             come
             to
             equality
             of
             weight
             ,
             but
             as
             soon
             the
             motion
             ends
             :
             because
             ,
             if
             the
             Glass
             halt
             at
             D
             ,
             E
             or
             F
             ,
             in
             the
             going
             down
             ,
             upon
             which
             follows
             a
             counterpoise
             ,
             then
             doth
             the
             creeping
             in
             of
             the
             Water
             cease
             .
             Sixthly
             ,
             there
             may
             be
             as
             much
             Pressure
             in
             a
             small
             quantity
             of
             a
             Fluid
             ,
             as
             in
             the
             greatest
             :
             because
             there
             is
             as
             much
             Bensil
             in
             the
             small
             portion
             of
             Air
             ,
             included
             between
             K
             and
             G
             ,
             as
             there
             is
             of
             Pressure
             ,
             and
             weight
             ,
             in
             this
             whole
             Water
             ,
             that
             's
             30
             fathom
             deep
             .
             Seventhly
             ,
             that
             the
             Pressure
             of
             a
             Fluid
             ,
             is
             a
             thing
             really
             distinct
             ,
             from
             the
             
               natural
               weight
            
             :
             this
             is
             evident
             from
             the
             Pressure
             of
             the
             inclosed
             Air
             G
             K
             ,
             that
             's
             more
             and
             less
             ,
             as
             the
             Pressure
             of
             the
             Water
             K
             M
             ,
             is
             more
             and
             less
             ,
             but
             the
             
               natural
               weight
            
             is
             still
             the
             same
             ,
             seing
             the
             same
             quantity
             remains
             .
             Eighthly
             ,
             one
             part
             of
             a
             Fluid
             ,
             cannot
             be
             under
             Pressure
             ,
             but
             the
             next
             adjacent
             ,
             must
             be
             under
             the
             same
             degree
             of
             Pressure
             :
             this
             is
             also
             clear
             ,
             because
             what
             ever
             degree
             of
             bensil
             the
             included
             Air
             K
             G
             is
             under
             ,
             the
             Water
             K
             M
             is
             under
             the
             same
             .
             Therefore
             ,
             when
             the
             one
             is
             under
             six
             ,
             as
             in
             the
             lowest
             fathom
             ,
             the
             other
             is
             under
             six
             likewise
             .
             And
             when
             the
             one
             is
             under
             five
             degrees
             of
             Pressure
             ,
             as
             in
             the
             surface
             F
             ,
             the
             other
             is
             under
             as
             much
             .
             Ninthly
             ,
             Bensil
             and
             Pressure
             are
             equivalent
             to
             weight
             :
             because
             the
             Water
             K
             M
             ,
             is
             as
             much
             burdened
             with
             the
             Bensil
             of
             that
             small
             portion
             of
             Air
             above
             it
             ,
             as
             if
             it
             had
             a
             Pillar
             of
             Water
             30
             fathom
             high
             upon
             it
             .
             Tenthly
             ,
             that
             the
             Pressure
             of
             Fluids
             ,
             is
             most
             uniform
             and
             equal
             ,
             and
             that
             two
             Fluids
             of
             different
             kinds
             ,
             may
             press
             as
             uniformly
             ,
             as
             if
             they
             were
             but
             one
             :
             this
             is
             evident
             from
             the
             sides
             of
             the
             Glass
             ,
             that
             are
             not
             broken
             
             in
             pieces
             ,
             by
             the
             strong
             Bensil
             of
             the
             inclosed
             Air
             ,
             and
             heavy
             Pressure
             of
             the
             inclosed
             Water
             ;
             and
             this
             happens
             because
             the
             Pressure
             without
             ,
             is
             as
             strong
             as
             the
             Pressure
             within
             .
             We
             see
             lastly
             ,
             that
             
               Water
               does
               not
               weigh
               in
               Water
               ,
            
             because
             when
             a
             man
             lets
             down
             this
             Glass
             by
             the
             chord
             ,
             to
             the
             lowest
             surface
             ,
             he
             finds
             not
             the
             weight
             of
             the
             Water
             K
             M
             ,
             that
             's
             within
             the
             Glass
             ,
             but
             only
             the
             weight
             of
             the
             Lead
             Q.
             'T
             is
             certain
             ,
             he
             finds
             not
             the
             weight
             of
             the
             Water
             I
             H
             ;
             because
             it
             rests
             not
             upon
             the
             Glass
             within
             ,
             but
             is
             sustained
             by
             '
             its
             own
             surface
             ,
             the
             mouth
             of
             the
             Glass
             being
             downward
             ,
             and
             open
             .
             When
             I
             say
             
               Water
               does
               not
               weigh
               in
               Water
            
             ;
             the
             meaning
             is
             not
             ,
             that
             Water
             wants
             weight
             or
             Pressure
             in
             it
             ,
             but
             that
             this
             weight
             and
             Pressure
             is
             not
             found
             ,
             as
             the
             weight
             and
             Pressure
             of
             other
             bodies
             are
             found
             ,
             while
             they
             are
             weighed
             in
             Water
             .
             For
             example
             ,
             a
             piece
             of
             Lead
             or
             Gold
             ,
             hung
             in
             the
             Water
             by
             a
             string
             ,
             the
             other
             end
             being
             fastened
             to
             a
             Ballance
             in
             the
             Air
             ,
             gravitats
             ,
             and
             weighs
             down
             the
             Scale
             ;
             and
             the
             reason
             is
             ,
             because
             Lead
             and
             Gold
             ,
             are
             naturally
             and
             specifically
             heavier
             than
             VVater
             ;
             but
             a
             piece
             of
             Metal
             of
             the
             same
             specifick
             weight
             with
             Water
             ,
             or
             VVater
             it self
             ,
             cannot
             gravitat
             in
             VVater
             ,
             or
             weigh
             down
             the
             Scale
             of
             a
             Ballance
             ;
             and
             the
             reason
             is
             ,
             because
             the
             surface
             of
             Water
             upon
             which
             they
             rest
             ,
             bears
             them
             up
             with
             as
             great
             weight
             and
             force
             ,
             as
             they
             press
             down
             with
             .
             If
             it
             be
             said
             ,
             that
             the
             Water
             K
             M
             ,
             rests
             upon
             the
             bottom
             of
             the
             Glass
             within
             ;
             and
             therefore
             ,
             if
             the
             man
             above
             ,
             find
             the
             weight
             of
             the
             Glass
             ,
             he
             must
             find
             the
             weight
             of
             the
             Water
             within
             it
             .
             I
             answer
             ,
             the
             consequence
             is
             bad
             ,
             because
             the
             weight
             of
             the
             Water
             within
             ,
             is
             sustained
             ,
             and
             counterpoised
             by
             the
             weight
             of
             the
             Water
             without
             ,
             whereupon
             the
             bottom
             of
             the
             Glass
             rests
             .
             That
             's
             to
             say
             ,
             as
             there
             is
             a
             Pillar
             of
             Water
             K
             M
             within
             
             the
             Glass
             ,
             that
             presseth
             down
             the
             bottom
             ,
             so
             there
             is
             a
             Pillar
             of
             Water
             without
             the
             Glass
             ,
             whereupon
             the
             bottom
             of
             the
             Glass
             rests
             ,
             and
             which
             bears
             up
             both
             .
             But
             the
             greater
             difficulty
             is
             this
             ,
             the
             further
             down
             the
             Glass
             goes
             ,
             it
             grows
             the
             heavier
             ,
             because
             of
             more
             and
             more
             Water
             ,
             that
             creeps
             in
             at
             G.
             Now
             't
             is
             certain
             ,
             the
             weight
             Q
             grows
             not
             heavier
             ,
             therefore
             it
             must
             be
             the
             Water
             within
             the
             Glass
             ,
             that
             makes
             the
             increase
             of
             the
             weight
             ;
             and
             therefore
             Water
             must
             still
             weigh
             in
             VVater
             .
             If
             this
             argument
             had
             any
             strength
             in
             it
             ,
             it
             would
             prove
             the
             weight
             of
             the
             VVater
             I
             H
             to
             gravitat
             and
             weigh
             likewise
             ;
             because
             the
             further
             down
             this
             glass
             goes
             ,
             it
             grows
             the
             heavier
             ,
             because
             of
             more
             ,
             and
             more
             Water
             ,
             that
             creeps
             up
             from
             H
             to
             I.
             Now
             't
             is
             certain
             ,
             the
             weight
             of
             Lead
             B
             grows
             not
             heavier
             .
             Behold
             ,
             the
             difficulty
             is
             the
             same
             in
             both
             ,
             and
             yet
             it
             were
             rashness
             to
             affirm
             the
             Water
             I
             H
             to
             be
             found
             by
             a
             mans
             hand
             ,
             when
             he
             pulls
             up
             the
             Glass
             with
             a
             string
             ,
             seing
             it
             is
             sustained
             by
             its
             own
             surface
             ,
             and
             not
             by
             any
             part
             of
             the
             Glass
             .
             Though
             this
             might
             suffice
             for
             an
             answer
             ,
             yet
             because
             the
             contrary
             is
             mantained
             by
             some
             ,
             and
             that
             with
             a
             new
             Experiment
             to
             prove
             it
             ,
             I
             shall
             be
             at
             some
             more
             pains
             to
             vindicat
             the
             truth
             of
             what
             I
             have
             said
             .
          
           
             This
             new
             Experiment
             to
             prove
             that
             
               Water
               weighs
               in
               Water
            
             ,
             I
             found
             in
             a
             
               Philosophical
               Transaction
            
             ,
             of
             August
             16.
             
             Anno
             1669.
             
             Numb
             .
             50
             ,
             the
             Invention
             whereof
             is
             attributed
             by
             the
             publisher
             ,
             to
             that
             honorable
             and
             worthy
             Person
             Mr.
             Boyl
             ,
             whose
             conclusions
             and
             trials
             ,
             I
             never
             much
             called
             in
             question
             ,
             but
             finding
             this
             opposite
             ,
             and
             contrary
             to
             what
             I
             have
             demonstrated
             ,
             I
             shall
             crave
             liberty
             to
             say
             ,
             
               amicus
               Socrates
               ,
               amicus
               Plato
               ,
               sed
               magis
               amica
               veritas
            
             ;
             and
             shall
             therefore
             examine
             it
             as
             briefly
             as
             may
             be
             .
             The
             words
             of
             the
             Publisher
             are
             as
             follows
             .
          
           
           
             The
             Author
             of
             this
             Invention
             is
             the
             Noble
             
               Robert
               Boyl
            
             ;
             who
             was
             pleased
             to
             comply
             with
             our
             desires
             ,
             of
             communicating
             it
             in
             English
             to
             the
             curious
             in
             England
             ,
             as
             by
             inserting
             the
             same
             in
             the
             Latine
             Translation
             of
             his
             
               Hydrostatical
               Paradoxes
            
             ,
             he
             hath
             gratified
             the
             Ingenious
             abroad
             .
             And
             it
             will
             doubtless
             be
             the
             more
             welcome
             ,
             for
             as
             much
             as
             no
             body
             ,
             we
             know
             of
             ,
             hath
             so
             much
             as
             attempted
             to
             determine
             ,
             how
             much
             Water
             may
             weigh
             in
             Water
             ;
             and
             possibly
             ,
             if
             such
             a
             Problem
             had
             been
             proposed
             ,
             it
             would
             have
             been
             judged
             impracticable
             .
          
           
             The
             Method
             or
             Expedient
             ,
             he
             made
             use
             of
             ,
             to
             perform
             it
             ,
             as
             near
             as
             he
             could
             ,
             may
             easily
             be
             learned
             by
             the
             ensuing
             accompt
             of
             a
             Trial
             or
             two
             ,
             he
             made
             for
             that
             purpose
             ,
             which
             among
             his
             Notes
             he
             caused
             to
             be
             registred
             in
             the
             following
             words
             .
          
           
             A
             Glass-bubble
             of
             about
             the
             bigness
             of
             a
             Pullets
             egg
             ,
             was
             purposely
             blown
             at
             the
             flame
             of
             a
             Lamp
             ,
             with
             a
             somewhat
             long
             stem
             turned
             up
             at
             the
             end
             ,
             that
             it
             might
             the
             more
             conveniently
             be
             broken
             off
             .
             This
             Bubble
             being
             well
             heated
             to
             rarify
             the
             Air
             ;
             and
             thereby
             drive
             out
             a
             good
             part
             of
             it
             ,
             was
             nimbly
             sealed
             at
             the
             end
             ,
             and
             by
             the
             help
             of
             the
             Figure
             of
             the
             stem
             ,
             was
             by
             a
             convenient
             Weight
             of
             Lead
             depressed
             under
             Water
             ,
             the
             Lead
             and
             Glass
             being
             tyed
             by
             a
             string
             to
             a
             Scale
             of
             a
             good
             Ballance
             ,
             in
             whose
             other
             there
             was
             put
             so
             much
             weight
             ,
             as
             sufficed
             to
             counterpoise
             the
             Bubble
             ,
             as
             it
             hung
             freely
             in
             the
             midst
             of
             the
             Water
             .
             Then
             with
             a
             long
             Iron
             Forceps
             ,
             I
             carefully
             broke
             off
             the
             seal'd
             end
             of
             the
             Bubble
             under
             Water
             ,
             so
             as
             no
             Bubble
             of
             Air
             appear'd
             to
             emerge
             or
             escape
             through
             the
             Water
             ,
             but
             the
             Liquor
             by
             the
             weight
             of
             the
             Atmosphere
             ,
             sprung
             into
             the
             un-replenish'd
             part
             of
             the
             Glass-Bubble
             ,
             and
             fill'd
             the
             whole
             cavity
             about
             half
             full
             ;
             and
             presently
             ,
             as
             I
             foretold
             ,
             the
             Bubble
             subsided
             ,
             and
             made
             the
             Scale
             't
             was
             fastned
             to
             ,
             preponderate
             so
             much
             ,
             that
             there
             needed
             4
             drachms
             ,
             and
             38
             grains
             to
             reduce
             the
             Ballance
             to
             an
             equilibrium
             .
             Then
             taking
             out
             the
             Bubble
             with
             the
             Water
             
             in
             it
             ,
             we
             did
             ,
             by
             the
             help
             of
             a
             flame
             of
             a
             Candle
             ,
             warily
             applyed
             ,
             drive
             out
             the
             Water
             (
             which
             otherwise
             is
             not
             easily
             excluded
             at
             a
             very
             narrow
             stem
             )
             into
             a
             Glass
             counterpoised
             before
             ;
             and
             we
             found
             it
             ,
             as
             we
             expected
             ,
             to
             weigh
             about
             four
             drachms
             and
             30
             grains
             ,
             besides
             some
             little
             that
             remained
             in
             the
             Egg
             ,
             and
             some
             small
             matter
             that
             might
             have
             been
             rarified
             into
             vapors
             ,
             which
             added
             to
             the
             piece
             of
             Glass
             that
             was
             broken
             off
             under
             Water
             and
             lost
             there
             ,
             might
             very
             well
             amount
             to
             7
             or
             8
             grains
             .
             By
             which
             it
             appears
             not
             only
             ,
             that
             Water
             hath
             some
             weight
             in
             Water
             ,
             but
             that
             it
             weighs
             very
             near
             ,
             or
             altogether
             as
             much
             in
             Water
             ,
             as
             the
             self
             same
             portion
             of
             Liquor
             would
             weigh
             in
             the
             Air.
             
          
           
             The
             same
             day
             we
             repeated
             the
             Experiment
             with
             another
             sealed
             Bubble
             ,
             larger
             then
             the
             former
             (
             being
             as
             big
             as
             a
             great
             Hens-egg
             )
             and
             having
             b●oken
             this
             under
             Water
             ,
             it
             grew
             heavier
             by
             7.
             drachms
             and
             34
             grains
             ;
             and
             having
             taken
             out
             the
             Bubble
             ,
             and
             driven
             out
             the
             Water
             into
             a
             counter
             pois'd
             Glass
             ,
             we
             found
             the
             transvasated
             Liquor
             to
             amount
             to
             the
             same
             weight
             ,
             abating
             6
             or
             7
             grains
             ,
             which
             it
             might
             well
             have
             lost
             upon
             such
             accompts
             ,
             as
             have
             been
             newly
             mentioned
             .
             
               Thus
               he
            
             .
          
           
             Figure
             24.
             
          
           
             THe
             design
             then
             of
             this
             Experiment
             is
             to
             prove
             
               that
               water
               weighs
               in
               Water
            
             ;
             but
             ,
             it
             seems
             ,
             there
             is
             here
             a
             very
             great
             mistake
             ,
             which
             I
             shall
             make
             out
             after
             this
             manner
             .
             For
             which
             cause
             ,
             let
             this
             Schematism
             24
             represent
             the
             Experiment
             already
             described
             .
             The
             ●lass-bubble
             then
             is
             E
             P
             F
             R.
             The
             stem
             is
             H
             C
             :
             the
             weight
             that
             sinks
             the
             Glass
             is
             B.
             The
             surface
             of
             Water
             under
             which
             it
             is
             drowned
             ,
             is
             A
             D.
             The
             Ballance
             to
             which
             the
             Glass
             is
             knit
             by
             a
             string
             is
             N
             O.
             And
             lastly
             E
             F
             R
             is
             the
             Water
             that
             came
             in
             ,
             and
             filled
             the
             half
             of
             the
             Bubble
             .
             
             Now
             I
             say
             ,
             it
             is
             not
             the
             weight
             of
             the
             Water
             E
             F
             R
             ,
             that
             turnes
             the
             Scales
             above
             ,
             and
             makes
             an
             alteration
             in
             the
             Ballance
             ,
             but
             '
             its
             only
             the
             weight
             of
             the
             Lead
             B
             ,
             that
             does
             it
             .
             For
             evincing
             this
             ,
             consider
             that
             all
             heavy
             bodies
             ,
             are
             either
             lighter
             in
             specie
             than
             Water
             ;
             as
             cork●
             or
             of
             the
             same
             specifick
             weight
             with
             it
             ,
             as
             some
             Wood
             is
             ,
             or
             last●y
             heavier
             in
             specie
             than
             Water
             ,
             as
             Lead
             or
             Gold.
             Now
             't
             is
             certain
             ,
             that
             bodies
             of
             the
             first
             sort
             cannot
             
               weigh
               in
               Water
            
             ,
             and
             the
             reason
             is
             ,
             because
             they
             being
             naturally
             lighter
             ,
             their
             whole
             weight
             is
             supported
             by
             the
             Water
             ,
             and
             therefore
             not
             one
             part
             of
             them
             ,
             can
             be
             born
             up
             by
             a
             Ballance
             above
             .
             A
             piece
             of
             Cork
             that
             weighs
             12
             ounces
             in
             the
             Air
             ,
             weighs
             nothing
             in
             Water
             ,
             because
             as
             soon
             as
             it
             toucheth
             the
             surface
             ,
             the
             whole
             weight
             of
             it
             is
             supported
             ,
             and
             therefore
             cannot
             affect
             the
             Ballance
             above
             .
             But
             bodies
             of
             the
             third
             sort
             ,
             as
             is
             clear
             from
             experience
             and
             reason
             ,
             does
             really
             weigh
             in
             Water
             :
             And
             the
             reason
             is
             ,
             because
             they
             being
             naturally
             heavier
             than
             water
             ,
             their
             whole
             weight
             cannot
             be
             supported
             by
             it
             ,
             and
             therefore
             some
             part
             of
             them
             must
             burden
             the
             Ballance
             ,
             to
             which
             the
             body
             is
             knit
             .
             A
             piece
             of
             Lead
             ,
             that
             weighs
             12
             ounces
             in
             the
             Air
             ,
             will
             not
             lose
             above
             2
             ounces
             ,
             when
             '
             its
             weighed
             in
             Water
             ;
             or
             may
             be
             less
             .
             But
             here
             there
             is
             no
             difficulty
             .
             The
             question
             then
             is
             ,
             in
             order
             to
             bodies
             of
             the
             same
             specifick
             weight
             with
             Water
             ,
             as
             some
             Wood
             is
             ,
             or
             as
             Water
             is
             .
             I
             say
             of
             such
             also
             ,
             that
             they
             cannot
             weigh
             in
             Water
             ;
             and
             the
             reason
             is
             ,
             because
             they
             being
             ●ust
             of
             the
             same
             weight
             ,
             must
             have
             their
             whole
             weight
             supported
             by
             it
             ;
             even
             as
             one
             foot
             of
             Water
             ,
             supports
             the
             whole
             weight
             of
             the
             foot
             above
             it
             .
             It
             may
             be
             evidenced
             after
             this
             manner
             .
             Take
             a
             piece
             of
             Wood
             ,
             that
             's
             lighter
             in
             specie
             than
             Water
             ,
             and
             add
             weight
             to
             it
             by
             degrees
             ,
             till
             it
             become
             of
             the
             
             same
             weight
             with
             Water
             .
             Knit
             it
             with
             a
             string
             to
             a
             Ballance
             ,
             ond
             weigh
             it
             in
             Water
             ,
             and
             you
             will
             find
             the
             whole
             weight
             supported
             by
             the
             Water
             .
             And
             the
             reason
             is
             ,
             because
             ,
             being
             left
             to
             it self
             ,
             it
             can
             go
             no
             further
             down
             ,
             than
             till
             the
             upper
             part
             of
             it
             ,
             be
             level
             with
             the
             surface
             of
             the
             Water
             .
             Now
             ,
             the
             whole
             weight
             being
             thus
             supported
             ,
             not
             one
             ounce
             of
             it
             can
             burden
             the
             Ballance
             .
             In
             a
             word
             ,
             the
             Ballance
             can
             never
             be
             burdened
             ,
             unless
             the
             body
             that
             's
             knit
             to
             it
             ,
             have
             an
             inclination
             to
             go
             to
             the
             ground
             ,
             when
             left
             to
             it self
             ,
             which
             a
             body
             of
             the
             same
             weight
             with
             Water
             can
             never
             have
             .
             I
             conclude
             then
             ,
             if
             a
             body
             of
             the
             same
             weight
             with
             Water
             ,
             cannot
             
               weigh
               in
               Water
            
             ,
             neither
             can
             
               Water
               weigh
               in
               Water
            
             ,
             seing
             Water
             is
             of
             the
             same
             weight
             with
             Water
             .
             And
             Therefore
             the
             Water
             E
             F
             R
             ,
             that
             's
             now
             within
             the
             Bubble
             ,
             cannot
             in
             anywise
             burden
             the
             Ballance
             above
             ;
             but
             must
             be
             supported
             wholly
             by
             the
             Water
             I
             K
             G
             H
             ,
             upon
             which
             the
             bottom
             of
             the
             Glass
             rests
             .
             If
             it
             be
             said
             ,
             that
             the
             Glass
             it self
             is
             supported
             by
             the
             Ballance
             ,
             because
             '
             it
             s
             heavier
             in
             specie
             than
             Water
             ;
             therefore
             the
             VVater
             within
             that
             rests
             upon
             the
             sides
             of
             it
             ,
             must
             be
             supported
             likewise
             by
             it
             .
             I
             answer
             ,
             the
             whole
             weight
             of
             the
             Glass
             is
             not
             supported
             ,
             by
             the
             Ballance
             ,
             but
             only
             a
             part
             ;
             the
             VVater
             I
             K
             G
             H
             supporting
             the
             other
             part
             .
             And
             this
             part
             is
             just
             as
             much
             as
             is
             the
             weight
             of
             VVater
             ,
             that
             's
             expelled
             by
             the
             Glass
             .
             Now
             ,
             if
             the
             said
             VVater
             support
             so
             much
             of
             the
             Glass
             ,
             because
             it
             is
             the
             just
             weight
             of
             so
             much
             VVater
             ,
             why
             should
             it
             not
             also
             ,
             support
             the
             VVater
             within
             the
             Glass
             ?
             Seing
             the
             VVater
             within
             the
             Glass
             ,
             is
             just
             the
             weight
             of
             as
             much
             VVater
             ,
             as
             will
             fill
             the
             space
             E
             F
             R.
             
          
           
             I
             come
             in
             the
             next
             place
             to
             shew
             ,
             that
             it
             is
             the
             weight
             
             of
             the
             Lead
             B
             that
             turns
             the
             Scales
             ,
             when
             the
             VVater
             comes
             in
             at
             C
             ,
             and
             fills
             the
             half
             of
             the
             sphere
             .
             For
             understanding
             this
             ,
             let
             us
             suppose
             first
             ,
             the
             weight
             that
             's
             in
             the
             Scale
             O
             to
             weigh
             six
             ounces
             .
             Secondly
             ,
             that
             the
             Glass
             takes
             12
             ounces
             to
             sink
             it
             compleatly
             under
             the
             surface
             A
             D.
             Thirdly
             ,
             the
             weight
             B
             to
             be
             18
             ounces
             ;
             namely
             for
             this
             cause
             ,
             first
             ,
             that
             12
             of
             it
             may
             sink
             the
             Glass
             ;
             next
             ,
             that
             the
             other
             six
             may
             counterpoise
             the
             six
             in
             the
             Scale
             O.
             Lastly
             ,
             that
             the
             VVater
             within
             the
             Glass
             weighs
             six
             ounces
             .
             I
             abstract
             from
             the
             weight
             of
             the
             Glass
             it self
             ,
             which
             is
             not
             considerable
             ,
             seing
             the
             most
             part
             of
             it
             ,
             is
             supported
             by
             the
             VVater
             ,
             and
             not
             by
             the
             Ballance
             .
             Now
             ,
             I
             say
             ,
             't
             is
             six
             ounces
             of
             the
             weight
             B
             that
             makes
             this
             alteration
             ,
             and
             turnes
             the
             Scales
             .
             For
             if
             12
             ounces
             sink
             the
             Glass
             below
             the
             VVater
             ,
             when
             '
             its
             full
             of
             Air
             ,
             and
             no
             Water
             in
             it
             ,
             then
             surely
             ●ix
             are
             sufficient
             to
             sink
             it
             ,
             when
             it
             is
             half
             full
             .
             And
             the
             reason
             is
             ,
             because
             there
             is
             a
             less
             Potentia
             or
             force
             in
             six
             inches
             of
             Air
             ,
             by
             the
             one
             half
             ,
             to
             counterpoise
             a
             weight
             of
             12
             ounces
             ,
             than
             in
             12
             inches
             of
             Air.
             Therefore
             this
             Air
             ,
             being
             reduced
             from
             12
             inches
             to
             six
             ,
             it
             must
             take
             only
             six
             ounces
             to
             sink
             it
             .
             If
             this
             be
             ,
             then
             the
             other
             six
             ounces
             that
             now
             wants
             a
             party
             to
             counterpoise
             them
             ,
             must
             burden
             the
             Ballance
             ,
             and
             be
             supported
             by
             the
             Scale
             :
             and
             therefore
             ,
             to
             make
             a
             new
             equipondium
             again
             ,
             you
             must
             make
             the
             weight
             O
             12
             ounces
             ,
             by
             adding
             six
             to
             it
             ,
             that
             it
             may
             counterpoise
             12
             of
             B
             ,
             the
             other
             six
             being
             counterpoised
             by
             the
             Air
             E
             P
             F.
             Let
             us
             suppose
             next
             ,
             this
             Glass
             to
             be
             compleatly
             full
             of
             VVater
             ,
             and
             the
             whole
             Air
             expelled
             .
             In
             this
             case
             the
             Scale
             O
             ,
             must
             have
             18
             ounces
             in
             it
             ,
             for
             making
             a
             new
             equip●ndium
             .
             The
             reason
             is
             ,
             because
             there
             being
             no
             Air
             in
             the
             Glass
             to
             counterpoise
             any
             part
             of
             B
             ,
             the
             whole
             weight
             of
             it
             must
             be
             
             sustained
             by
             the
             Ballance
             ,
             and
             therefore
             in
             the
             Scale
             O
             ,
             there
             must
             be
             18.
             
             Now
             ,
             I
             enquire
             ,
             whether
             these
             18
             ounces
             ,
             are
             the
             equipondium
             of
             the
             VVater
             within
             the
             Glass
             ,
             or
             of
             the
             weight
             of
             Lead
             B
             ?
             'T
             is
             impossible
             it
             can
             counterpoise
             them
             both
             ,
             seing
             the
             VVater
             is
             now
             12
             ,
             and
             B
             18.
             
             It
             must
             then
             either
             be
             the
             counterballance
             of
             the
             Water
             ,
             or
             the
             counterballance
             of
             the
             Lead
             .
             It
             cannot
             be
             the
             first
             ,
             because
             12
             cannot
             be
             in
             equipondio
             with
             18
             ,
             It
             must
             then
             be
             the
             second
             .
             Or
             if
             these
             18
             ounces
             in
             the
             Scale
             O
             ,
             be
             the
             counterpoise
             of
             the
             Water
             within
             the
             Glass
             ,
             I
             enquire
             what
             sustains
             the
             weight
             of
             the
             Lead
             B
             ?
             The
             weight
             of
             it
             ,
             cannot
             be
             sustained
             by
             the
             Water
             ,
             because
             't
             is
             a
             body
             naturally
             heavier
             than
             Water
             ,
             it
             must
             therefore
             be
             sustained
             by
             the
             Ballance
             ,
             I
             conclude
             then
             ,
             that
             
               Water
               cannot
               weigh
               in
               Water
            
             .
             If
             it
             be
             objected
             ,
             that
             this
             conclusion
             seems
             to
             contradict
             ,
             and
             oppose
             the
             Pressure
             of
             the
             Water
             ,
             that
             's
             been
             hitherto
             confirmed
             with
             so
             many
             Experiments
             .
             I
             answer
             ,
             the
             
               Pressure
               of
               the
               Water
            
             is
             one
             thing
             ,
             and
             
               Water
               to
               weigh
               in
               Water
            
             is
             another
             .
             The
             first
             is
             ,
             when
             one
             Pillar
             of
             Water
             counterpoises
             another
             ,
             or
             when
             a
             Pillar
             of
             Water
             counterpoises
             a
             Pillar
             of
             Mercury
             ,
             or
             is
             counterpoised
             by
             a
             Pillar
             of
             Air
             ,
             all
             which
             is
             in
             order
             to
             the
             
               Natural
               Ballance
            
             ,
             wherein
             bodies
             weigh
             only
             according
             to
             altitude
             .
             The
             second
             is
             ,
             when
             VVater
             is
             not
             counterpoised
             by
             VVater
             ,
             or
             by
             Mercury
             ,
             or
             by
             Air
             ,
             or
             by
             any
             other
             Fluid
             ;
             but
             when
             '
             its
             weighed
             by
             a
             piece
             of
             Lead
             or
             stone
             in
             an
             
               Artificial
               Ballance
            
             ,
             for
             knowing
             how
             many
             ounces
             or
             pounds
             it
             is
             of
             ,
             as
             if
             a
             man
             should
             endeavour
             to
             weigh
             the
             Water
             E
             F
             R
             by
             help
             of
             the
             Ballance
             above
             ,
             which
             in
             effect
             is
             impossible
             .
          
        
         
           
           
             EXPERIMENT
             XVIII
             .
             Figure
             25.
             
          
           
             MAke
             a
             
               Wooden
               Ark
            
             after
             this
             following
             manner
             .
             The
             Planks
             must
             be
             of
             Oak
             ,
             an
             inch
             thick
             .
             The
             height
             40
             inches
             .
             The
             breadth
             36.
             
             Closs
             on
             all
             sides
             ,
             and
             above
             ,
             and
             open
             below
             .
             And
             because
             the
             form
             is
             four-square
             ,
             there
             must
             be
             four
             Standarts
             of
             Timber
             ,
             in
             each
             corner
             one
             ,
             to
             which
             the
             Planks
             must
             be
             nailed
             .
             Four
             likewise
             upon
             the
             top
             ,
             crossing
             the
             other
             four
             at
             right
             angles
             ,
             to
             which
             the
             cover
             must
             be
             joyned
             .
             The
             sides
             must
             be
             plained
             ,
             and
             the
             edges
             both
             plained
             and
             gripped
             in
             all
             the
             parts
             ,
             that
             the
             joynings
             may
             be
             closs
             .
             Upon
             the
             top
             fasten
             a
             strong
             Iron
             Ring
             ,
             as
             at
             N
             ,
             through
             which
             must
             be
             fastned
             a
             Rope
             ,
             of
             so
             many
             foot
             or
             fathom
             .
             And
             because
             the
             use
             of
             this
             Engine
             is
             for
             Diving
             under
             the
             Water
             ,
             it
             must
             therefore
             be
             all
             covered
             over
             with
             Pitch
             within
             and
             without
             ,
             especially
             in
             the
             couplings
             .
             And
             because
             this
             Instrument
             cannot
             sink
             of
             its
             own
             accord
             ,
             it
             must
             have
             a
             great
             weight
             of
             Lead
             appended
             to
             it
             ,
             for
             that
             cause
             ,
             whereupon
             the
             Divers
             feet
             must
             stand
             ,
             while
             he
             is
             in
             going
             down
             .
             The
             precise
             quantity
             and
             weight
             of
             it
             cannot
             be
             determined
             ;
             because
             it
             depends
             upon
             the
             quantity
             of
             the
             Ark
             ,
             which
             if
             large
             ,
             requires
             a
             great
             weight
             :
             if
             of
             a
             lesser
             size
             ,
             requires
             a
             lesser
             weight
             .
             But
             whatever
             the
             dimensions
             of
             the
             Ark
             may
             be
             ,
             the
             weight
             of
             the
             Leaden-foot-stool
             can
             easily
             be
             found
             out
             by
             trial
             .
             This
             Invention
             then
             ,
             is
             for
             Diving
             ,
             a
             most
             excellent
             Art
             ,
             for
             lifting
             up
             of
             
               Guns
               ,
               Ships
            
             ,
             or
             any
             other
             things
             ,
             that
             are
             drowned
             below
             the
             Water
             .
             And
             it
             is
             in
             imitation
             of
             the
             
               Diving
               bell
            
             ,
             already
             found
             out
             ,
             and
             made
             use
             of
             with
             success
             .
             It
             is
             called
             a
             Bell
             ,
             because
             of
             the
             form
             ,
             that
             represents
             a
             
             Church-bell
             indeed
             ,
             being
             round
             ,
             wide
             below
             ,
             and
             narrower
             in
             the
             top
             :
             only
             ,
             the
             matter
             is
             of
             Lead
             .
             It
             seems
             ,
             it
             is
             of
             this
             mettal
             ,
             first
             ,
             because
             Lead
             is
             weighty
             ,
             and
             will
             therefore
             easily
             sink
             :
             secondly
             ,
             because
             it
             's
             easily
             founded
             ,
             and
             will
             by
             this
             means
             ,
             being
             of
             one
             piece
             ,
             be
             free
             of
             rifts
             ,
             and
             leaks
             :
             thirdly
             ,
             it
             being
             of
             Lead
             ,
             will
             be
             of
             a
             considerable
             strength
             for
             resisting
             the
             force
             of
             the
             VVater
             ,
             that
             ordinarily
             breaks
             in
             pieces
             Vessels
             that
             are
             weak
             .
             I
             cannot
             well
             divine
             and
             guess
             the
             reason
             ,
             why
             first
             it
             is
             round
             ,
             and
             next
             narrower
             above
             ,
             than
             below
             ,
             unless
             ,
             because
             its
             more
             easily
             founded
             after
             this
             way
             ,
             than
             after
             another
             .
             This
             device
             here
             described
             is
             named
             a
             
               Diving
               Ark
            
             ;
             first
             ,
             because
             it
             is
             of
             Timber
             ,
             and
             next
             ,
             because
             it
             saves
             a
             man
             from
             being
             overwhelmed
             with
             the
             Waters
             .
             I
             prescribe
             it
             of
             Wood
             ,
             because
             of
             less
             trouble
             ,
             and
             expence
             in
             making
             of
             it
             .
             'T
             is
             four
             square
             ,
             because
             it
             contains
             under
             this
             Figure
             ,
             far
             more
             Air
             ,
             than
             if
             it
             were
             round
             ;
             even
             as
             much
             more
             ,
             as
             a
             square
             Vessel
             30
             inches
             wide
             ,
             contains
             more
             than
             a
             round
             Vessel
             30
             inches
             wide
             .
             Now
             ,
             the
             more
             Air
             ,
             that
             's
             in
             the
             Vessel
             ,
             the
             easier
             is
             the
             respiration
             ,
             and
             the
             longer
             time
             is
             the
             man
             able
             to
             abide
             under
             the
             VVater
             ,
             which
             two
             things
             are
             of
             great
             advantage
             to
             this
             Art.
             For
             if
             by
             a
             guess
             we
             reckon
             ,
             how
             much
             more
             Air
             is
             in
             the
             one
             ,
             than
             in
             the
             other
             ,
             we
             will
             find
             in
             the
             Ark
             ,
             as
             before
             it
             is
             described
             ,
             30
             square
             foot
             of
             Air
             ,
             but
             in
             the
             Bell
             ,
             though
             it
             be
             36
             inches
             wide
             ,
             as
             well
             above
             ,
             as
             below
             ,
             yet
             little
             more
             than
             23
             will
             be
             found
             ,
             which
             is
             a
             considerable
             difference
             .
             But
             far
             less
             must
             be
             in
             it
             ,
             seing
             it's
             narrower
             above
             ,
             than
             below
             .
             Besides
             this
             advantage
             ,
             there
             are
             others
             very
             useful
             :
             for
             being
             of
             Wood
             ,
             it
             's
             more
             tractable
             .
             Next
             ,
             several
             Knags
             of
             Iron
             may
             be
             fastened
             conveniently
             to
             the
             sides
             within
             ,
             to
             which
             a
             man
             fastning
             his
             hands
             ,
             may
             keep
             his
             body
             fixed
             and
             sure
             in
             going
             
             down
             ,
             and
             coming
             up
             .
             Moreover
             ,
             if
             a
             man
             were
             in
             hazard
             to
             be
             confounded
             with
             fear
             ,
             or
             lose
             the
             right
             exercise
             of
             his
             senses
             ,
             and
             so
             be
             in
             danger
             of
             falling
             out
             of
             the
             Ark
             ;
             or
             if
             his
             feet
             should
             slide
             off
             the
             foot-stool
             ,
             and
             his
             hands
             fail
             him
             too
             ,
             a
             chord
             knit
             to
             one
             of
             those
             ,
             and
             fastened
             about
             his
             wast
             or
             middle
             ,
             might
             bring
             him
             up
             ,
             though
             he
             were
             dead
             .
             Then
             ,
             it
             s
             far
             easier
             to
             cut
             out
             a
             window
             or
             two
             in
             the
             sides
             of
             it
             ,
             not
             very
             large
             ,
             but
             little
             ,
             as
             K
             and
             I
             ,
             whereby
             ,
             they
             being
             covered
             with
             Glass
             ,
             a
             man
             may
             see
             at
             a
             distance
             ,
             what
             's
             upon
             the
             right
             hand
             ,
             and
             what
             's
             upon
             the
             left
             ,
             and
             what
             is
             before
             .
             This
             device
             is
             of
             excellent
             use
             ,
             for
             through
             the
             want
             of
             it
             ,
             the
             Diver
             sees
             no
             more
             ,
             but
             what
             is
             just
             below
             him
             ,
             which
             sometimes
             ,
             when
             he
             is
             near
             the
             ground
             ,
             will
             not
             exceed
             the
             compass
             of
             a
             large
             Mil●wheel
             .
             But
             if
             so
             be
             ,
             three
             holes
             be
             cut
             thorow
             ,
             one
             on
             every
             hand
             ,
             and
             one
             before
             ,
             he
             may
             see
             as
             much
             bounds
             ,
             and
             all
             things
             in
             it
             ,
             as
             if
             he
             were
             not
             inclosed
             ,
             and
             invironed
             with
             a
             cover
             .
             A
             little
             schelf
             likewise
             may
             be
             fixed
             upon
             the
             one
             side
             or
             the
             other
             ,
             for
             holding
             a
             Compass
             with
             a
             Magnetical
             Needle
             ,
             for
             knowing
             how
             such
             and
             such
             a
             thing
             lies
             in
             the
             ground
             of
             the
             Sea.
             In
             one
             of
             the
             corners
             may
             hing
             a
             little
             bottle
             with
             some
             excellent
             spirits
             ,
             for
             refreshing
             the
             stomach
             ,
             under
             VVater
             .
             Many
             moe
             advantages
             I
             might
             name
             ,
             this
             Engine
             being
             of
             Timber
             ,
             but
             shall
             forbear
             ;
             leaving
             the
             collection
             of
             them
             to
             the
             ingenious
             Reader
             ,
             and
             proceeds
             to
             answer
             some
             objections
             ,
             that
             may
             be
             made
             against
             it
             .
          
           
             First
             ,
             if
             this
             Engine
             be
             made
             of
             Wood
             ,
             it
             will
             not
             sink
             so
             easily
             ,
             as
             being
             made
             of
             Lead
             .
             I
             answer
             ,
             this
             difficulty
             is
             soon
             overcome
             ,
             namely
             by
             making
             the
             Foot-stool
             the
             heavier
             :
             therefore
             how
             light
             soever
             it
             be
             ,
             a
             weight
             may
             be
             found
             to
             counterpoise
             it
             in
             the
             VVater
             .
             If
             it
             be
             judged
             
             too
             light
             in
             Timber
             ,
             it
             may
             be
             lined
             with
             Lead
             ,
             especially
             without
             .
             Secondly
             ,
             if
             it
             be
             of
             VVood
             ,
             there
             must
             be
             couplings
             and
             joynings
             in
             it
             ,
             and
             so
             rifts
             and
             leaks
             in
             it
             ,
             through
             which
             the
             VVater
             may
             come
             .
             I
             answer
             ,
             there
             is
             less
             difficulty
             here
             ,
             than
             in
             the
             former
             ;
             because
             the
             joynts
             may
             be
             made
             so
             closs
             in
             all
             the
             parts
             ,
             and
             may
             be
             so
             covered
             over
             with
             pitch
             ,
             or
             with
             some
             such
             like
             matter
             ,
             that
             it
             may
             defie
             either
             Water
             to
             come
             in
             ,
             or
             Air
             to
             go
             out
             .
             Thirdly
             ,
             if
             it
             be
             made
             of
             VVood
             ,
             it
             will
             be
             in
             hazard
             of
             breaking
             by
             the
             force
             of
             the
             VVater
             :
             for
             oft
             times
             its
             found
             ,
             that
             the
             strongest
             Hogshead
             will
             burst
             asunder
             by
             the
             Pressure
             of
             it
             ,
             if
             they
             go
             but
             down
             7
             or
             8
             fathom
             .
             I
             answer
             ,
             this
             objection
             flows
             from
             the
             ignorance
             of
             the
             nature
             of
             Fluid
             bodies
             .
             If
             so
             be
             then
             ,
             that
             a
             man
             knew
             ,
             that
             the
             Pressure
             of
             VVater
             is
             uniform
             ,
             most
             equal
             ,
             and
             presseth
             upon
             all
             the
             parts
             of
             a
             body
             within
             it
             alike
             ,
             no
             such
             scruple
             would
             occurre
             .
             I
             say
             then
             ,
             the
             Ark
             ,
             though
             no
             thicker
             in
             the
             sides
             ,
             than
             a
             thin
             sawen
             dale
             ,
             will
             go
             down
             ,
             in
             spight
             of
             all
             the
             Pressure
             that
             's
             in
             the
             VVater
             ,
             not
             only
             10
             ,
             but
             20
             ,
             or
             30
             fathom
             ,
             without
             all
             hazard
             .
             And
             the
             reason
             is
             ,
             because
             what
             Pressure
             soever
             is
             without
             ,
             to
             press
             in
             the
             sides
             ,
             the
             same
             degree
             of
             Pressure
             is
             within
             to
             press
             them
             out
             .
             By
             this
             means
             ,
             there
             is
             not
             one
             part
             of
             the
             VVater
             ,
             how
             deep
             soever
             ,
             to
             which
             the
             Ark
             may
             come
             down
             ,
             but
             there
             will
             be
             found
             as
             much
             force
             in
             the
             Air
             within
             ,
             as
             will
             counterballance
             the
             whole
             weight
             without
             ,
             as
             will
             be
             infallibly
             demonstrated
             afterwards
             .
             This
             answers
             a
             fourth
             objection
             ,
             namely
             if
             holes
             be
             cut
             out
             in
             the
             sides
             of
             the
             Ark
             ,
             in
             stead
             of
             windows
             ,
             the
             force
             of
             the
             VVater
             will
             break
             the
             Glasses
             in
             pieces
             ,
             that
             covers
             them
             .
             There
             is
             here
             no
             hazard
             ,
             though
             the
             said
             windows
             were
             12
             inches
             in
             Diameter
             :
             but
             it
             s
             not
             needful
             they
             be
             so
             large
             .
             It
             's
             sufficient
             ,
             
             if
             they
             be
             2
             inches
             wide
             :
             for
             a
             mans
             eye
             near
             to
             a
             hole
             ,
             2
             inches
             wide
             ,
             will
             see
             a
             great
             way
             about
             him
             .
             There
             's
             a
             necessity
             the
             Glasses
             be
             joyned
             in
             with
             cement
             ,
             that
             Water
             may
             not
             have
             access
             to
             come
             in
             ,
             or
             Air
             to
             go
             out
             .
             In
             such
             a
             case
             ther
             's
             no
             hazard
             ,
             that
             the
             Pressure
             of
             the
             VVater
             ,
             will
             break
             through
             the
             windows
             ,
             or
             break
             the
             Glasses
             ;
             because
             the
             Pressure
             of
             the
             Air
             within
             ,
             being
             of
             the
             same
             force
             with
             the
             strength
             of
             the
             VVater
             without
             ,
             the
             Glasses
             are
             keeped
             intire
             .
             It
             may
             be
             enquired
             ,
             what
             hazard
             would
             follow
             ,
             upon
             supposition
             a
             small
             hole
             were
             pierced
             in
             the
             head
             of
             the
             Ark
             above
             ,
             when
             it
             is
             going
             down
             ?
             I
             answer
             ,
             ther
             's
             not
             so
             much
             hazard
             ,
             as
             a
             man
             would
             think
             ;
             provided
             the
             hole
             be
             not
             wide
             ,
             but
             narrow
             .
             If
             it
             be
             wide
             ,
             not
             only
             the
             VVater
             comes
             in
             ,
             but
             the
             Air
             goes
             out
             ,
             the
             one
             thrusting
             it self
             by
             the
             other
             .
             If
             the
             hole
             be
             no
             wider
             ,
             than
             the
             point
             of
             a
             bodkin
             is
             in
             thickness
             ;
             ther
             's
             no
             danger
             at
             all
             :
             for
             by
             reason
             of
             the
             strait
             passage
             ;
             the
             one
             cannot
             thrust
             it self
             by
             the
             other
             ,
             and
             therefore
             neither
             the
             VVater
             can
             come
             in
             ,
             nor
             the
             Air
             go
             out
             .
             And
             this
             comes
             to
             pass
             ,
             by
             reason
             ,
             that
             the
             Air
             within
             ,
             is
             as
             strong
             as
             the
             Water
             is
             without
             .
             Now
             ,
             if
             they
             be
             both
             of
             the
             same
             strength
             and
             force
             ,
             why
             ought
             the
             Air
             rather
             to
             go
             out
             ,
             then
             the
             Water
             to
             come
             in
             ;
             or
             the
             Water
             rather
             to
             come
             in
             ,
             then
             the
             Air
             to
             go
             out
             ?
             I
             am
             confident
             ,
             though
             the
             hole
             were
             as
             wide
             ,
             as
             a
             man
             might
             thrust
             in
             his
             little
             finger
             ,
             yet
             no
             irruption
             of
             Water
             ,
             or
             eruption
             of
             Air
             would
             follow
             .
             This
             demonstrats
             clearly
             ,
             that
             though
             a
             small
             rift
             ,
             or
             leak
             should
             happen
             in
             the
             Ark
             ,
             yet
             no
             hazard
             or
             danger
             would
             follow
             thereupon
             .
             If
             it
             be
             inquired
             ,
             whither
             the
             greatest
             hazard
             is
             from
             the
             ingress
             of
             the
             Water
             ,
             or
             from
             the
             egress
             of
             the
             Air
             ?
             I
             answer
             ,
             ther
             's
             no
             danger
             from
             the
             coming
             in
             of
             the
             Water
             from
             above
             ;
             because
             
             as
             it
             comes
             in
             ,
             it
             falls
             down
             ,
             and
             so
             mingles
             with
             the
             rest
             below
             .
             But
             if
             the
             Air
             should
             go
             out
             ,
             the
             Ark
             fills
             presently
             full
             of
             Water
             ,
             and
             drowns
             the
             man
             that
             is
             in
             it
             .
          
           
             The
             next
             thing
             considerable
             in
             this
             
               Diving
               Instrument
            
             ,
             is
             the
             foot-stool
             of
             Lead
             C
             D
             ,
             that
             's
             not
             only
             useful
             for
             a
             man
             to
             set
             his
             feet
             upon
             ,
             when
             he
             dives
             ;
             but
             especially
             for
             sinking
             of
             the
             Ark.
             For
             this
             being
             made
             of
             Timber
             ;
             and
             full
             of
             Air
             ,
             cannot
             of
             '
             its
             own
             accord
             go
             down
             ,
             unless
             it
             be
             pulled
             ,
             and
             forced
             by
             some
             weight
             .
             It
             may
             either
             be
             broad
             and
             round
             ,
             or
             square
             :
             if
             square
             ,
             a
             large
             foot
             over
             from
             side
             to
             side
             ,
             or
             16
             inches
             will
             determine
             the
             breadth
             .
             By
             this
             means
             ,
             it
             will
             happen
             to
             be
             pretty
             thick
             ,
             seing
             a
             great
             quantity
             of
             Lead
             is
             required
             .
             In
             each
             corner
             ,
             there
             must
             be
             a
             hole
             ,
             for
             four
             chords
             ,
             by
             which
             it
             is
             appended
             to
             the
             mouth
             of
             the
             Ark.
             Between
             it
             ,
             and
             the
             roof
             within
             ,
             must
             be
             the
             height
             of
             a
             man
             and
             more
             .
             The
             weight
             of
             it
             ,
             cannot
             be
             well
             determined
             without
             trial
             ;
             seing
             it
             depends
             upon
             the
             dimensions
             of
             the
             Ark.
             First
             then
             try
             ,
             how
             much
             weight
             ,
             will
             bring
             the
             top
             E
             F
             G
             H
             level
             with
             the
             surface
             of
             the
             Water
             .
             When
             this
             is
             found
             ,
             add
             a
             little
             more
             weight
             till
             it
             begin
             to
             sink
             ,
             and
             this
             will
             surely
             take
             it
             to
             the
             ground
             ,
             though
             it
             were
             40
             fathom
             .
             'T
             is
             to
             be
             observed
             ,
             that
             when
             the
             top
             E
             F
             is
             level
             with
             the
             surface
             ,
             there
             is
             here
             a
             just
             counterpoise
             ,
             namely
             between
             the
             
               Lead
               foot-stool
            
             on
             the
             one
             part
             ,
             as
             a
             pondus
             ,
             and
             the
             Ark
             on
             the
             other
             part
             ,
             as
             a
             potentia
             ;
             for
             with
             what
             force
             the
             Ark
             endeavours
             to
             pull
             up
             the
             Lead
             ;
             with
             the
             same
             force
             strives
             the
             Lead
             to
             pull
             down
             the
             Ark.
             Hence
             it
             is
             ,
             that
             as
             a
             small
             weight
             will
             turn
             a
             pair
             of
             Scales
             ,
             when
             they
             are
             in
             equilibrio
             ;
             so
             a
             small
             weight
             added
             to
             the
             foot-stool
             will
             sink
             the
             Ark.
             Though
             it
             may
             seem
             difficult
             to
             determine
             the
             just
             weight
             of
             the
             foot-stool
             ,
             without
             trial
             
             as
             I
             said
             ,
             yet
             I
             purpose
             to
             essay
             it
             .
             For
             this
             cause
             consider
             that
             there
             is
             no
             Vessel
             of
             VVood
             almost
             ,
             if
             it
             be
             once
             full
             of
             Water
             ,
             but
             the
             orifice
             of
             it
             will
             ly
             level
             with
             the
             surface
             of
             the
             VVater
             ,
             wherein
             it
             sweems
             .
             This
             proposition
             is
             so
             evident
             from
             experience
             ,
             that
             it
             needs
             no
             confirmation
             .
             From
             this
             I
             gather
             ,
             that
             as
             much
             weight
             of
             Lead
             or
             Stone
             will
             bring
             the
             top
             of
             the
             Ark
             E
             F
             G
             H
             ,
             level
             with
             the
             surface
             of
             the
             VVater
             ,
             as
             is
             the
             weight
             of
             the
             Water
             ,
             that
             fills
             it
             .
             If
             you
             suppose
             then
             the
             Ark
             to
             be
             36
             inches
             broad
             ,
             and
             40
             inches
             high
             ,
             it
             must
             contain
             30
             cubique
             foot
             of
             Water
             .
             Now
             ,
             supposing
             each
             square
             foot
             of
             this
             Water
             to
             weigh
             56
             pound
             ,
             30
             foot
             must
             weigh
             1680
             pound
             .
             This
             is
             gathered
             from
             trial
             and
             experience
             ,
             for
             after
             exact
             search
             ,
             I
             found
             a
             cubique
             foot
             of
             Water
             ,
             in
             bulk
             about
             16
             pints
             of
             our
             measure
             ,
             to
             weigh
             56
             pound
             .
             Take
             then
             a
             piece
             of
             Lead
             of
             that
             weight
             ,
             and
             you
             will
             find
             it
             make
             a
             just
             counterpoise
             with
             the
             Ark.
             If
             any
             be
             desirous
             to
             know
             the
             quantity
             of
             it
             .
             I
             answer
             ,
             if
             lead
             be
             13
             times
             naturally
             heavier
             then
             Water
             ,
             you
             will
             find
             that
             a
             piece
             of
             Lead
             about
             16
             inches
             every
             way
             will
             do
             it
             .
             If
             it
             be
             objected
             ,
             that
             when
             a
             mans
             body
             is
             within
             the
             Ark
             ,
             the
             weight
             of
             the
             foot-stool
             must
             be
             less
             ,
             even
             as
             much
             less
             ,
             as
             is
             the
             weight
             of
             the
             man
             ,
             whom
             I
             suppose
             to
             weigh
             224
             pound
             ,
             or
             14
             stone
             .
             I
             answer
             ,
             the
             whole
             weight
             of
             the
             man
             is
             not
             to
             be
             deduced
             from
             the
             foot-stool
             ,
             but
             the
             one
             half
             only
             ,
             and
             the
             reason
             is
             ,
             because
             a
             mans
             body
             being
             of
             the
             same
             specifick
             and
             natural
             weight
             with
             Water
             ,
             it
             cannot
             preponderat
             or
             weigh
             in
             VVater
             ,
             because
             magnitudes
             only
             naturally
             heavier
             then
             VVater
             weigh
             in
             VVater
             ,
             as
             Lead
             ,
             or
             Stone
             ;
             therefore
             seing
             the
             one
             half
             of
             the
             man
             is
             within
             the
             Ark
             ,
             and
             the
             other
             without
             among
             the
             Water
             ,
             that
             part
             only
             
             must
             weigh
             ,
             that
             's
             invironed
             with
             Air.
             This
             may
             seem
             a
             plausible
             answer
             ,
             and
             might
             do
             much
             to
             satisfy
             these
             ,
             that
             are
             not
             very
             inquisitive
             ,
             yet
             ,
             being
             examined
             ,
             it
             will
             be
             found
             unsufficient
             .
             Therefore
             ,
             I
             say
             ,
             there
             's
             not
             one
             part
             of
             the
             mans
             body
             ,
             that
             weighs
             within
             the
             Ark
             ,
             or
             makes
             it
             heavier
             .
             Yet
             ,
             I
             affirm
             ,
             that
             when
             the
             mans
             body
             is
             within
             the
             Ark
             ,
             a
             less
             weight
             will
             sink
             it
             ,
             then
             when
             his
             body
             is
             out
             of
             it
             ,
             even
             as
             much
             less
             than
             before
             ,
             as
             is
             the
             just
             weight
             of
             the
             one
             half
             of
             the
             man.
             For
             example
             ,
             if
             1680
             pound
             be
             the
             just
             counterpoise
             of
             it
             without
             the
             Man
             ,
             then
             after
             the
             Man
             is
             in
             it
             ,
             it
             will
             take
             only
             1568
             pound
             to
             counterballance
             it
             ,
             supposing
             the
             one
             half
             of
             the
             man
             to
             weigh
             112
             pound
             ,
             or
             seven
             stone
             :
             yet
             it
             is
             not
             the
             weight
             of
             the
             man
             that
             makes
             this
             difference
             .
             For
             understanding
             what
             's
             the
             cause
             of
             this
             alteration
             ,
             consider
             ,
             that
             when
             a
             mans
             body
             is
             within
             the
             Ark
             ,
             there
             is
             less
             Air
             in
             it
             ,
             then
             while
             his
             body
             is
             out
             of
             it
             ,
             even
             as
             much
             less
             in
             quantity
             ,
             as
             the
             bulk
             of
             the
             parts
             are
             ,
             that
             are
             within
             .
             If
             this
             be
             ,
             then
             must
             the
             Ark
             become
             heavier
             ,
             not
             because
             the
             mans
             body
             makes
             it
             heavier
             ,
             but
             because
             there
             is
             less
             Air
             ,
             in
             the
             Ark
             ,
             then
             before
             ,
             and
             therefore
             ,
             there
             arises
             an
             inequality
             between
             the
             weight
             of
             the
             foot-stool
             and
             the
             weight
             ,
             or
             rather
             lightness
             of
             the
             Ark.
             For
             if
             1680
             pound
             of
             Lead
             ,
             was
             the
             just
             counterballance
             of
             it
             ,
             when
             it
             had
             30
             cubique
             foot
             of
             Air
             within
             it
             ,
             it
             must
             exceed
             ,
             when
             there
             is
             less
             Air
             in
             it
             .
             But
             there
             occures
             ,
             here
             two
             difficulties
             ,
             the
             first
             is
             ,
             what
             's
             the
             reason
             ,
             why
             as
             much
             weight
             must
             be
             deduced
             from
             the
             foot-stool
             ,
             as
             is
             the
             the
             precise
             weight
             of
             the
             one
             half
             of
             the
             man
             ?
             Secondly
             ,
             how
             shall
             we
             come
             to
             the
             true
             knowledge
             of
             that
             weight
             ;
             that
             is
             ,
             to
             know
             distinctly
             how
             many
             pounds
             or
             ounces
             it
             is
             of
             ?
             For
             answer
             ,
             let
             us
             suppose
             ,
             that
             the
             one
             half
             of
             
             the
             man
             ,
             is
             just
             as
             heavy
             ,
             as
             so
             much
             Water
             equal
             in
             bulk
             to
             his
             own
             half
             .
             This
             may
             be
             granted
             without
             scruple
             ,
             seing
             a
             mans
             body
             is
             judged
             to
             be
             of
             the
             same
             specifick
             ,
             and
             natural
             weight
             with
             Water
             :
             and
             though
             there
             should
             be
             some
             small
             difference
             ,
             yet
             it
             will
             not
             make
             ,
             or
             produce
             any
             insufficiency
             in
             the
             argument
             ,
             for
             these
             demonstrations
             ,
             are
             not
             Mathematical
             but
             Physical
             .
             Therefore
             ,
             as
             much
             Water
             in
             bulk
             ,
             as
             is
             equal
             to
             that
             part
             of
             the
             man
             ,
             that
             is
             within
             the
             Ark
             ,
             must
             be
             as
             heavy
             ,
             as
             the
             half
             of
             the
             man.
             Now
             supposing
             the
             half
             of
             the
             man
             ,
             to
             weigh
             112
             pound
             ,
             and
             consequently
             that
             Water
             ,
             to
             weigh
             as
             much
             ,
             I
             affirm
             the
             said
             Water
             to
             contain
             3456
             cubique
             inches
             :
             but
             3456
             cubique
             inches
             ,
             makes
             exactly
             two
             cubique
             feet
             ,
             which
             I
             gather
             thus
             .
             Seven
             pound
             of
             Water
             requires
             216
             cubique
             inches
             ,
             because
             a
             Cube
             of
             six
             inches
             ,
             weighs
             exactly
             seven
             pound
             ,
             therefore
             according
             to
             the
             rule
             of
             proportion
             ,
             112
             pound
             will
             require
             3456
             inches
             ,
             which
             amounts
             to
             two
             cubique
             foot
             .
             The
             Ark
             then
             by
             receiving
             the
             one
             half
             of
             the
             mans
             body
             ,
             loseth
             two
             cubique
             foot
             of
             Air
             ,
             therefore
             if
             30
             foot
             of
             Air
             ,
             require
             1680
             pound
             weight
             of
             Lead
             to
             counterpoise
             it
             ,
             28
             foot
             of
             Air
             ,
             must
             require
             only
             1568
             pound
             :
             therefore
             to
             make
             a
             new
             counterballance
             ,
             you
             must
             deduce
             112
             pound
             from
             the
             foot-stool
             .
             This
             answers
             both
             the
             difficulties
             .
             If
             it
             be
             said
             ,
             that
             the
             foot-stool
             weighs
             less
             in
             VVater
             than
             in
             Air
             ,
             therefore
             it
             must
             be
             heavier
             ,
             then
             1680
             pound
             .
             I
             answer
             ,
             't
             is
             needful
             to
             abstract
             from
             that
             difference
             ,
             till
             the
             just
             calculation
             be
             once
             made
             ,
             and
             that
             being
             now
             done
             ,
             I
             say
             ,
             that
             a
             Cube
             of
             Lead
             16
             inches
             weighing
             1680
             pound
             ,
             (
             If
             Lead
             be
             13
             times
             heavier
             than
             VVater
             ,
             )
             will
             lose
             about
             130
             pound
             .
             The
             reason
             is
             evident
             ,
             because
             a
             heavy
             body
             weighs
             as
             much
             
             less
             in
             VVater
             than
             in
             Air
             ,
             as
             is
             the
             weight
             of
             the
             Water
             it
             expells
             .
             But
             so
             it
             is
             ,
             that
             a
             Cube
             of
             Lead
             of
             16
             inches
             expells
             a
             Cube
             of
             VVater
             16
             inches
             :
             But
             a
             Cube
             of
             VVater
             16
             inches
             weighs
             130
             pound
             ,
             which
             I
             gather
             thus
             .
             216
             inches
             ,
             or
             a
             Cube
             of
             six
             inches
             ,
             weighs
             seven
             pound
             ,
             therefore
             4032
             inches
             ,
             must
             weigh
             130
             pound
             .
             For
             if
             216
             give
             7,4032
             must
             give
             130.
             
             But
             to
             return
             .
             Though
             there
             be
             small
             difficulty
             to
             let
             it
             down
             and
             to
             sink
             it
             20
             or
             30
             fathom
             ,
             yet
             there
             is
             no
             small
             difficulty
             to
             pull
             it
             up
             again
             .
             And
             the
             reason
             is
             this
             ,
             because
             the
             further
             down
             it
             goes
             ,
             the
             Air
             within
             ,
             is
             the
             more
             contracted
             ,
             and
             thrust
             up
             ,
             by
             the
             Pressure
             of
             the
             Water
             ,
             towards
             the
             roof
             .
             By
             this
             means
             ,
             though
             near
             the
             top
             of
             the
             Water
             ,
             there
             was
             little
             difference
             between
             the
             weight
             of
             the
             Lead
             and
             the
             Ark
             ;
             yet
             9
             or
             10
             fathom
             down
             ,
             the
             difference
             is
             great
             ,
             the
             weight
             of
             the
             one
             ,
             far
             exceeding
             the
             weight
             of
             the
             other
             ,
             and
             therefore
             there
             must
             be
             greater
             difficulty
             to
             pull
             it
             up
             from
             10
             fathom
             ,
             than
             from
             5
             :
             and
             yet
             more
             difficulty
             from
             20
             than
             from
             10.
             
             However
             ,
             yet
             't
             is
             observable
             that
             ,
             as
             the
             Ark
             in
             going
             down
             ,
             becomes
             heavier
             and
             heavier
             ,
             so
             in
             coming
             up
             ,
             it
             growes
             lighter
             and
             lighter
             :
             therefore
             less
             strength
             is
             required
             ,
             in
             pulling
             it
             up
             from
             the
             tenth
             to
             the
             fifth
             fathom
             ,
             than
             from
             the
             fifteenth
             ,
             to
             the
             tenth
             :
             the
             reason
             is
             ,
             because
             in
             coming
             up
             ,
             the
             Air
             within
             expands
             it self
             ,
             and
             fills
             more
             space
             in
             the
             Ark
             ,
             which
             in
             effect
             makes
             it
             lighter
             ,
             and
             more
             able
             to
             overcome
             the
             weight
             of
             the
             Lead
             .
             To
             make
             these
             things
             more
             evident
             ,
             let
             us
             suppose
             ,
             that
             when
             the
             Ark
             is
             down
             18
             or
             20
             fathom
             ,
             the
             Air
             to
             be
             contracted
             by
             the
             force
             of
             the
             Water
             ,
             from
             L
             M
             to
             P
             Q
             12
             inches
             .
             Next
             ,
             that
             the
             weight
             of
             the
             foot-stool
             is
             1680
             pound
             .
             Now
             ,
             if
             this
             weight
             was
             the
             just
             counterpoise
             of
             the
             Ark
             ,
             
             at
             the
             top
             of
             the
             Water
             ,
             then
             surely
             it
             must
             far
             exceed
             it
             now
             ,
             when
             it
             's
             20
             fathom
             down
             ,
             because
             the
             Air
             that
             was
             30
             foot
             ,
             is
             now
             reduced
             to
             21.
             
             Count
             then
             ,
             and
             you
             will
             find
             ,
             that
             if
             30
             require
             1680
             ,
             21
             will
             only
             require
             1176
             :
             therefore
             the
             weight
             of
             the
             Lead
             ,
             will
             exceed
             the
             weight
             of
             the
             Ark
             ,
             at
             20
             fathom
             deep
             ,
             by
             504
             pound
             .
             This
             will
             be
             yet
             more
             evident
             ,
             if
             we
             consider
             ,
             that
             while
             the
             top
             of
             the
             Ark
             E
             F
             G
             H
             ,
             is
             level
             with
             the
             surface
             above
             ,
             the
             VVater
             thrust
             out
             of
             '
             its
             own
             place
             by
             this
             bulk
             ,
             is
             just
             the
             weight
             of
             both
             Lead
             and
             Ark.
             But
             when
             '
             its
             down
             20
             fathom
             ,
             and
             the
             Air
             reduced
             from
             L
             M
             to
             P
             Q
             ,
             there
             cannot
             be
             so
             much
             VVater
             expelled
             now
             as
             before
             ,
             seing
             the
             space
             L
             M
             P
             Q
             is
             full
             of
             VVater
             .
             Now
             ,
             I
             say
             ,
             the
             Lead
             at
             20
             fathom
             ,
             must
             be
             exactly
             so
             much
             heavier
             than
             the
             Ark
             ,
             as
             is
             the
             weight
             of
             the
             said
             VVater
             L
             M
             P
             Q
             ,
             which
             in
             effect
             will
             be
             504.
             pound
             :
             for
             '
             its
             a
             square
             body
             ,
             36
             inches
             in
             thickness
             and
             12
             in
             deepness
             .
             The
             weight
             of
             the
             rope
             is
             likewise
             to
             be
             considered
             ,
             that
             lets
             down
             the
             Ark
             :
             for
             the
             longer
             it
             be
             ,
             and
             more
             of
             it
             goes
             out
             ,
             it
             's
             the
             heavier
             ,
             and
             more
             troublesome
             to
             pull
             up
             .
          
           
             There
             is
             no
             way
             to
             cure
             this
             difficulty
             ,
             but
             by
             finding
             out
             a
             way
             ,
             how
             to
             keep
             a
             just
             counterpoise
             between
             the
             Lead
             and
             the
             Ark
             ,
             all
             the
             time
             it
             is
             in
             going
             down
             .
             If
             the
             Air
             within
             did
             not
             contract
             it self
             ,
             no
             difference
             would
             happen
             :
             but
             this
             is
             impossible
             ,
             so
             long
             as
             the
             Water
             is
             under
             a
             Pressure
             .
             The
             expedient
             then
             must
             be
             found
             out
             another
             way
             ,
             namely
             by
             kniting
             a
             small
             rope
             to
             the
             iron
             ring
             N
             ,
             in
             length
             with
             the
             other
             ,
             to
             which
             at
             certain
             distances
             ,
             relating
             to
             the
             fathoms
             the
             Ark
             goes
             down
             ,
             must
             be
             fastned
             empty
             little
             Vessels
             of
             Wood
             ,
             or
             bladders
             ,
             which
             by
             their
             lightness
             ,
             may
             compense
             the
             decrement
             
             and
             decreasing
             of
             the
             Air.
             First
             then
             ,
             let
             down
             the
             Ark
             three
             fathom
             ,
             and
             see
             how
             much
             it
             is
             heavier
             than
             before
             :
             and
             as
             you
             find
             the
             difference
             ,
             so
             fasten
             to
             R
             one
             Bladder
             ,
             or
             two
             ,
             till
             the
             Ark
             be
             brought
             near
             to
             a
             counterpoise
             .
             Secondly
             ,
             let
             it
             go
             down
             other
             three
             fathom
             ,
             and
             observe
             that
             difference
             also
             ,
             and
             accordingly
             fasten
             to
             T
             as
             many
             ,
             as
             will
             reduce
             the
             two
             to
             a
             counterpoise
             again
             .
             Do
             after
             this
             manner
             ,
             till
             it
             sink
             15
             or
             20
             fathom
             .
             'T
             is
             to
             be
             observed
             ,
             that
             the
             further
             down
             the
             Ark
             goes
             ,
             the
             difference
             is
             the
             less
             :
             therefore
             less
             addition
             will
             serve
             :
             and
             the
             reason
             is
             ,
             because
             there
             is
             less
             Air
             contracted
             ,
             in
             passing
             between
             the
             fifth
             and
             the
             tenth
             fathom
             ;
             than
             in
             passing
             from
             the
             first
             to
             the
             fifth
             .
             The
             proportion
             of
             contraction
             is
             represented
             by
             the
             unequal
             divisions
             within
             the
             mouth
             of
             the
             Ark
             ,
             as
             1.
             2.
             3.
             4.
             
             In
             a
             word
             ,
             by
             what
             proportion
             the
             decrement
             of
             the
             Air
             is
             ,
             by
             that
             same
             proportion
             must
             the
             addition
             be
             ,
             upon
             the
             rope
             S
             N.
             Suppose
             then
             ,
             the
             Air
             to
             be
             diminished
             four
             inches
             ,
             in
             going
             down
             four
             fathom
             ,
             which
             will
             be
             5184
             square
             inches
             ,
             or
             three
             square
             foot
             ,
             then
             surely
             as
             much
             Air
             must
             be
             added
             to
             the
             rope
             S
             N
             ,
             by
             bladders
             .
             In
             going
             down
             as
             far
             ,
             let
             us
             suppose
             three-inches
             to
             be
             contracted
             ;
             then
             less
             will
             suffice
             .
             Though
             it
             cannot
             be
             determined
             without
             trial
             ,
             how
             much
             Air
             is
             contracted
             in
             three
             fathom
             ,
             and
             how
             much
             in
             six
             ,
             and
             how
             much
             in
             nine
             ;
             yet
             this
             is
             sure
             ,
             that
             the
             decreasing
             is
             according
             to
             unequal
             divisions
             ,
             that
             's
             to
             say
             ,
             less
             in
             six
             than
             in
             four
             ,
             less
             in
             8
             ,
             than
             in
             six
             ,
             and
             less
             in
             10
             ,
             than
             in
             8
             ,
             and
             so
             downward
             :
             and
             that
             this
             is
             the
             rule
             ,
             namely
             according
             to
             what
             quantity
             ,
             the
             Air
             within
             the
             Ark
             is
             contracted
             ,
             according
             to
             that
             same
             measure
             ,
             must
             the
             addition
             of
             Air
             be
             to
             the
             rope
             .
             If
             it
             be
             said
             ,
             that
             Bladders
             full
             of
             wind
             ,
             cannot
             go
             down
             thorow
             the
             VVater
             without
             bursting
             .
             
             I
             answer
             ,
             't
             is
             a
             mistake
             ,
             because
             their
             sides
             being
             pliable
             ,
             and
             not
             stiff
             like
             the
             sides
             of
             a
             Timber
             Vessel
             ,
             they
             yeeld
             ,
             and
             therefore
             cannot
             burst
             .
             It
             's
             observable
             that
             when
             a
             bladder
             goes
             far
             down
             ,
             the
             sides
             becomes
             flaccid
             and
             flagging
             .
             In
             this
             case
             ,
             the
             Air
             ,
             that
             before
             ,
             had
             the
             forme
             of
             the
             Bladder
             ,
             and
             was
             somewhat
             ovall
             ,
             must
             now
             become
             perfectly
             globular
             ,
             and
             round
             :
             for
             't
             is
             sure
             ,
             that
             the
             dimensions
             of
             it
             are
             altered
             by
             the
             Pressure
             of
             the
             VVater
             ,
             namely
             from
             more
             quantity
             to
             less
             :
             if
             this
             be
             ,
             then
             the
             form
             must
             be
             round
             ,
             seing
             the
             Pressure
             of
             the
             Water
             is
             most
             uniform
             ;
             even
             as
             drops
             of
             VVater
             ,
             or
             Rain
             from
             a
             house
             side
             are
             round
             upon
             this
             account
             .
             This
             second
             way
             ,
             may
             be
             thought
             upon
             also
             .
             Make
             the
             
               Leaden
               foot-stool
            
             that
             sinks
             the
             Ark
             ,
             not
             of
             one
             piece
             ,
             but
             of
             many
             ,
             that
             so
             ,
             when
             the
             Air
             within
             it
             ,
             begins
             to
             be
             contracted
             by
             degrees
             ,
             in
             going
             down
             ,
             a
             proportionable
             weight
             may
             be
             subtracted
             ,
             for
             keeping
             a
             just
             counterpoise
             ,
             all
             the
             while
             of
             the
             descent
             .
             Or
             because
             the
             greatest
             trouble
             is
             in
             bringing
             of
             it
             up
             ,
             let
             the
             Diver
             ,
             when
             once
             he
             is
             at
             the
             bottom
             ,
             subtract
             so
             much
             weight
             from
             the
             foot-stool
             ,
             as
             he
             thinks
             will
             go
             near
             to
             make
             a
             counterpoise
             ,
             at
             that
             deepness
             .
             For
             example
             ,
             if
             the
             weight
             of
             the
             foot-stool
             be
             40
             pound
             heavier
             than
             the
             Ark
             ,
             then
             let
             him
             subtract
             30
             or
             36
             ,
             which
             may
             ly
             ,
             and
             rest
             upon
             the
             ground
             ,
             till
             it
             be
             drawen
             up
             ,
             at
             a
             convenient
             time
             ,
             by
             a
             chord
             .
             By
             his
             means
             it
             will
             be
             easie
             to
             move
             the
             Ark
             ,
             from
             one
             place
             to
             another
             .
             Next
             ,
             there
             shall
             be
             little
             or
             no
             difficulty
             to
             pull
             it
             up
             .
             Nay
             ,
             upon
             supposition
             ,
             the
             rope
             were
             broken
             ,
             by
             which
             it
             was
             let
             down
             ,
             yet
             if
             the
             Diver
             please
             ,
             he
             may
             come
             up
             without
             any
             mans
             help
             .
             And
             this
             is
             most
             easily
             done
             ,
             namely
             by
             subtracting
             as
             much
             weight
             ,
             as
             will
             make
             the
             Ark
             the
             stronger
             party
             .
             'T
             is
             to
             be
             observed
             ,
             that
             
             when
             you
             are
             at
             the
             bottom
             ,
             and
             if
             you
             make
             the
             Lead
             but
             one
             pound
             lighter
             than
             the
             Ark
             ,
             it
             will
             surely
             come
             up
             ,
             and
             cannot
             stop
             by
             the
             way
             .
             The
             reason
             is
             ,
             because
             a
             very
             small
             weight
             will
             turn
             the
             Scales
             ,
             between
             two
             bodies
             ,
             thus
             weighing
             in
             VVater
             .
             Next
             ,
             the
             further
             the
             Ark
             comes
             up
             ,
             it
             becomes
             the
             lighter
             ,
             because
             the
             Air
             within
             it
             ,
             expands
             it self
             the
             more
             .
             But
             leaving
             this
             ,
             let
             us
             come
             to
             explicat
             the
             reason
             ,
             why
             the
             contraction
             of
             the
             Air
             is
             not
             uniform
             ,
             but
             rather
             difform
             .
             For
             if
             in
             going
             down
             three
             fathom
             ,
             three
             inches
             be
             contracted
             ,
             there
             will
             not
             be
             other
             three
             contracted
             in
             going
             down
             the
             second
             three
             ,
             but
             less
             :
             and
             yet
             less
             in
             going
             down
             the
             third
             three
             .
             Two
             things
             then
             are
             to
             be
             explicated
             here
             .
             First
             ,
             why
             there
             is
             a
             contraction
             .
             Next
             ,
             why
             it
             is
             after
             such
             a
             manner
             .
             As
             for
             the
             first
             ;
             the
             contraction
             is
             caused
             by
             the
             Pressure
             of
             the
             Water
             ,
             which
             gradually
             increaseth
             from
             the
             top
             to
             the
             bottom
             ;
             as
             is
             clear
             from
             the
             last
             Experiment
             :
             therefore
             ,
             there
             being
             a
             greater
             Pressure
             in
             a
             surface
             six
             fathom
             deep
             ,
             than
             in
             a
             surface
             three
             fathom
             deep
             ,
             the
             Air
             within
             the
             Ark
             ,
             must
             be
             more
             contracted
             in
             passing
             between
             the
             third
             and
             sixth
             ,
             than
             in
             passing
             between
             the
             first
             and
             third
             .
             When
             I
             say
             more
             contracted
             ,
             the
             meaning
             is
             ,
             that
             more
             quantity
             is
             contracted
             to
             less
             ,
             whereby
             the
             Bensil
             of
             it
             is
             more
             intended
             ;
             or
             that
             the
             Air
             is
             more
             bended
             .
             As
             for
             the
             second
             ,
             we
             must
             remember
             from
             the
             last
             Experiment
             ,
             that
             the
             cause
             of
             this
             ,
             is
             not
             from
             the
             VVater
             ,
             as
             if
             forsooth
             the
             Pressure
             of
             it
             ,
             were
             according
             to
             unequal
             proportion
             ,
             but
             from
             the
             Air
             it self
             ,
             whose
             kind
             and
             nature
             it
             is
             ,
             to
             suffer
             compression
             after
             such
             a
             way
             .
             'T
             is
             evident
             in
             Wind-guns
             ,
             whose
             second
             span
             of
             Air
             is
             comprest
             with
             greater
             difficulty
             ,
             than
             the
             first
             :
             and
             the
             third
             with
             greater
             difficulty
             ,
             than
             the
             second
             .
             'T
             is
             so
             with
             
             all
             bodies
             endowed
             with
             Benfil
             :
             for
             ay
             the
             longer
             you
             bend
             ,
             you
             find
             the
             greater
             difficulty
             .
             As
             there
             is
             a
             great
             disadvantage
             to
             the
             man
             that
             Dives
             ,
             from
             the
             contraction
             of
             the
             Air
             ,
             so
             there
             is
             a
             great
             advantage
             to
             him
             ,
             from
             this
             manner
             and
             way
             of
             contraction
             ;
             for
             if
             it
             were
             uniform
             ,
             according
             to
             the
             Pressure
             of
             the
             Water
             ,
             then
             if
             three
             fathom
             comprest
             three
             inches
             ,
             six
             fathom
             ought
             to
             compresse
             six
             inches
             ,
             nine
             fathom
             nine
             inches
             ,
             and
             so
             forward
             ,
             till
             by
             going
             down
             ,
             either
             the
             whole
             Air
             ,
             should
             be
             comprest
             to
             no
             inches
             ,
             or
             else
             very
             little
             should
             remain
             for
             respiration
             .
          
           
             The
             next
             thing
             to
             be
             taken
             notice
             of
             ,
             is
             that
             all
             the
             while
             ,
             during
             the
             down
             going
             of
             the
             Ark
             ,
             there
             is
             still
             equality
             of
             weight
             ,
             between
             the
             Pondus
             of
             the
             Water
             ,
             and
             the
             Potentia
             of
             the
             Air
             ,
             for
             with
             what
             degree
             of
             weight
             ,
             the
             Water
             presseth
             up
             the
             Air
             ,
             with
             the
             same
             degree
             of
             force
             and
             power
             ,
             doeth
             the
             Air
             press
             down
             the
             Water
             .
             If
             this
             were
             not
             ,
             it
             would
             be
             impossible
             for
             a
             man
             to
             go
             down
             ;
             because
             of
             pain
             .
             For
             when
             one
             part
             of
             a
             mans
             body
             ,
             is
             less
             prest
             than
             another
             ,
             there
             ariseth
             a
             considerable
             pain
             ,
             which
             sometimes
             is
             intolerable
             ,
             as
             is
             evident
             from
             the
             application
             of
             Ventoso-glasses
             .
             This
             equality
             of
             weight
             ,
             is
             the
             true
             reason
             ,
             why
             respiration
             is
             so
             easie
             .
             Yet
             't
             is
             to
             be
             observed
             ,
             that
             a
             man
             cannot
             breath
             so
             easily
             in
             the
             Ark
             ,
             under
             the
             Water
             ,
             as
             above
             in
             the
             Air
             ▪
             not
             because
             there
             is
             any
             inequality
             ,
             between
             the
             weight
             of
             the
             VVater
             ,
             and
             the
             force
             of
             the
             Air
             ;
             but
             only
             because
             the
             quantity
             of
             it
             is
             little
             .
             For
             when
             a
             man
             sucks
             in
             as
             much
             Air
             ,
             as
             fills
             his
             lungs
             ,
             the
             quantity
             must
             be
             diminished
             :
             if
             this
             be
             ,
             the
             Water
             must
             ascend
             by
             proportion
             ,
             though
             insensibly
             .
             When
             a
             man
             thrusts
             out
             the
             same
             Air
             again
             ,
             the
             quantity
             is
             increased
             ;
             if
             this
             be
             ,
             then
             the
             Water
             must
             subside
             a
             little
             ;
             both
             which
             cannot
             be
             ,
             
             without
             difficulty
             ,
             seing
             there
             is
             a
             sort
             of
             ebbing
             and
             flowing
             both
             of
             the
             Air
             and
             of
             the
             Water
             ,
             in
             every
             respiration
             .
             But
             it
             rather
             seems
             (
             you
             say
             )
             that
             this
             difficulty
             flowes
             from
             the
             strong
             ,
             extraordinary
             bensil
             ,
             that
             the
             Air
             is
             under
             .
             I
             answer
             ,
             as
             long
             as
             the
             pressure
             of
             a
             Fluid
             is
             uniform
             ,
             though
             in
             a
             high
             degree
             ,
             yet
             there
             can
             be
             no
             trouble
             in
             respiration
             ;
             because
             with
             what
             force
             soever
             ,
             it
             is
             driven
             in
             upon
             the
             lungs
             ,
             with
             the
             same
             force
             it
             is
             driven
             out
             again
             :
             therefore
             ,
             though
             the
             Air
             we
             live
             in
             ,
             were
             as
             much
             again
             bended
             as
             it
             is
             ,
             yet
             (
             as
             is
             probable
             )
             we
             would
             find
             no
             more
             difficulty
             in
             breathing
             than
             now
             .
             There
             is
             one
             thing
             makes
             breathing
             easie
             under
             the
             Water
             ,
             in
             the
             Ark
             ,
             namely
             this
             ;
             when
             a
             man
             sucks
             in
             the
             Air
             to
             his
             lungs
             ,
             his
             breast
             and
             belly
             goes
             out
             ,
             and
             so
             fills
             the
             space
             deserted
             by
             the
             Air
             ,
             that
             goes
             in
             .
             This
             makes
             the
             ebbing
             and
             flowing
             far
             less
             .
          
           
             From
             this
             equality
             of
             weight
             between
             the
             pressure
             of
             the
             VVater
             ,
             and
             the
             pressure
             of
             the
             Air
             ,
             we
             see
             good
             ground
             to
             say
             ,
             that
             though
             the
             Ark
             ,
             were
             no
             thicker
             in
             the
             sides
             ,
             than
             a
             thin
             sawed
             dale
             ,
             yet
             there
             would
             be
             no
             hazard
             of
             breaking
             .
             I
             am
             confident
             ,
             though
             it
             were
             no
             stronger
             in
             the
             sides
             ,
             than
             a
             wine-glass
             ,
             that
             's
             soon
             broken
             ;
             yet
             it
             might
             go
             down
             40
             fathom
             without
             hazard
             ,
             or
             danger
             of
             bursting
             .
             This
             affords
             good
             ground
             likewise
             to
             make
             windows
             in
             the
             Ark
             covered
             with
             glass
             :
             for
             if
             the
             Pressure
             be
             uniform
             ,
             and
             equal
             ,
             its
             impossible
             they
             can
             be
             broken
             .
             The
             VVater
             cannot
             thrust
             them
             inward
             ,
             because
             the
             Pressure
             of
             the
             Air
             ,
             is
             as
             able
             to
             thrust
             them
             outward
             .
          
           
             It
             's
             certain
             ,
             the
             more
             Air
             be
             in
             the
             Ark
             ,
             the
             more
             easie
             is
             respiration
             :
             therefore
             it
             s
             more
             easie
             to
             breath
             ,
             when
             the
             Ark
             is
             but
             down
             5
             fathom
             ,
             than
             when
             it
             is
             down
             10
             or
             15.
             
             It
             's
             probable
             a
             man
             might
             live
             within
             the
             Ark
             ,
             it
             being
             40
             inches
             deep
             ,
             and
             36
             inches
             wide
             ,
             at
             the
             deepness
             of
             
             ten
             fathom
             ,
             near
             two
             houres
             ;
             whereas
             if
             it
             were
             round
             ,
             and
             narrow
             above
             in
             form
             of
             a
             Bell
             ,
             he
             could
             not
             continue
             an
             hour
             .
             It
             were
             very
             easie
             to
             try
             how
             long
             other
             creatures
             might
             live
             in
             it
             ,
             for
             example
             dogs
             ,
             and
             such
             like
             ,
             or
             fowls
             ,
             as
             hens
             ,
             pheasants
             or
             doves
             .
             They
             might
             easily
             be
             inclosed
             from
             coming
             out
             ;
             for
             though
             the
             whole
             mouth
             of
             the
             Ark
             were
             shut
             up
             ,
             except
             as
             much
             passage
             ,
             as
             would
             receive
             a
             mans
             fist
             ,
             yet
             it
             will
             operate
             ,
             as
             well
             that
             way
             ,
             as
             the
             other
             .
             And
             there
             ,
             a
             little
             door
             might
             be
             made
             to
             open
             ,
             and
             shut
             at
             pleasure
             .
             'T
             is
             observed
             ,
             that
             by
             long
             tarrying
             under
             the
             Water
             in
             the
             Bell
             ,
             the
             Air
             becomes
             gross
             and
             misty
             ,
             which
             hinders
             a
             man
             from
             seing
             about
             him
             .
             The
             cause
             of
             this
             ,
             are
             vapors
             that
             come
             from
             the
             stomach
             ,
             lungs
             and
             other
             parts
             of
             the
             body
             ,
             especially
             from
             the
             stomach
             ,
             when
             the
             ventricle
             is
             full
             of
             meat
             .
             It
             's
             not
             fit
             then
             ,
             that
             a
             man
             about
             to
             dive
             ,
             should
             eat
             too
             much
             ,
             or
             drink
             too
             much
             ,
             especially
             such
             liquors
             as
             Sack
             or
             Brandy
             ,
             that
             beget
             many
             fumes
             and
             vapors
             .
             If
             a
             man
             were
             necessitated
             to
             tarry
             a
             pretty
             while
             below
             ,
             fresh
             Air
             might
             be
             sent
             down
             from
             above
             ,
             in
             bottles
             or
             bladders
             ,
             even
             as
             much
             as
             might
             fill
             up
             the
             place
             deserted
             by
             the
             contracted
             Air.
             'T
             is
             observed
             by
             some
             ,
             that
             have
             been
             under
             the
             VVater
             ,
             that
             their
             eares
             have
             been
             so
             troubled
             ,
             that
             for
             a
             long
             time
             ,
             they
             have
             found
             difficulty
             to
             hear
             distinctly
             .
             The
             reason
             of
             this
             must
             be
             from
             the
             great
             Pressure
             ,
             the
             tympanum
             hath
             suffered
             from
             the
             imprisoned
             Air
             of
             the
             Bell.
             The
             Organ
             of
             hearing
             is
             soon
             troubled
             ,
             especially
             when
             a
             man
             is
             near
             to
             a
             great
             gun
             ,
             when
             it
             's
             fired
             .
             And
             surely
             ,
             when
             a
             man
             is
             but
             34
             foot
             down
             ,
             the
             Air
             within
             the
             Ark
             ,
             will
             be
             of
             double
             Bensil
             :
             put
             the
             case
             the
             man
             go
             down
             68
             foot
             ,
             or
             13
             or
             14
             fathom
             ,
             the
             Bensil
             is
             tripled
             :
             that
             's
             to
             say
             ,
             if
             the
             Air
             above
             have
             five
             degrees
             of
             Pressure
             in
             it
             ,
             the
             Air
             of
             the
             Bell
             ,
             at
             68
             foot
             deep
             ,
             will
             
             have
             15
             degrees
             of
             Pressure
             ;
             therefore
             the
             tympanum
             of
             the
             ear
             that
             's
             but
             a
             small
             and
             thin
             membran
             ,
             must
             be
             sore
             distressed
             ;
             that
             is
             overbended
             ,
             and
             prest
             inward
             ;
             even
             as
             ,
             while
             a
             man
             sets
             upon
             a
             drum
             head
             a
             great
             weight
             ,
             v.
             g.
             a
             Bullet
             of
             Lead
             or
             Iron
             ,
             of
             20
             or
             30
             pound
             ,
             the
             skin
             by
             this
             ,
             suffers
             an
             extraordinary
             Pressure
             ,
             whereby
             it
             is
             in
             hazard
             to
             be
             rent
             .
             'T
             is
             probable
             ,
             if
             a
             man
             should
             go
             very
             far
             down
             ,
             the
             tympanum
             might
             be
             in
             hazard
             of
             breaking
             ,
             or
             being
             rent
             in
             two
             pieces
             ,
             there
             being
             a
             greater
             Pressure
             upon
             the
             one
             side
             from
             the
             Air
             without
             ,
             than
             upon
             the
             other
             side
             ,
             from
             the
             internal
             Air
             within
             ,
             which
             is
             thought
             to
             be
             within
             the
             tympanum
             .
          
           
             There
             remains
             another
             Phenomenon
             to
             be
             explicated
             ,
             and
             it
             's
             this
             :
             the
             further
             up
             the
             Ark
             comes
             from
             the
             ground
             of
             the
             Water
             ,
             towards
             the
             top
             ,
             the
             Water
             within
             it
             ,
             subsides
             and
             settles
             down
             more
             and
             more
             ,
             towards
             the
             mouth
             .
             The
             reason
             of
             it
             is
             ,
             because
             the
             further
             up
             ,
             the
             Pressure
             of
             the
             Water
             is
             the
             less
             ;
             and
             therefore
             the
             contracted
             Air
             gets
             liberty
             to
             expand
             ,
             and
             dilate
             it self
             ,
             and
             so
             thrusts
             down
             the
             Water
             from
             P
             Q
             to
             L
             M.
             In
             a
             word
             ,
             by
             what
             proportion
             the
             Air
             is
             contracted
             in
             going
             down
             ,
             by
             that
             same
             proportion
             it
             dilates
             ,
             and
             opens
             it self
             in
             coming
             up
             .
             This
             lets
             us
             see
             ,
             as
             there
             is
             disadvantage
             in
             going
             down
             ,
             from
             the
             contraction
             of
             the
             Air
             ,
             so
             there
             is
             advantage
             in
             coming
             up
             ,
             from
             the
             dilatation
             of
             it
             .
             Some
             think
             ,
             that
             the
             coldness
             of
             the
             Water
             is
             the
             cause
             ,
             why
             the
             Air
             is
             contracted
             in
             the
             Ark
             ,
             such
             are
             those
             ,
             who
             deny
             the
             Pressure
             of
             it
             .
             But
             this
             fancy
             is
             easily
             refuted
             ;
             because
             in
             asserting
             this
             ,
             they
             must
             maintain
             ,
             the
             further
             down
             ,
             the
             cold
             is
             the
             greater
             .
             If
             this
             be
             ,
             then
             far
             more
             Air
             must
             be
             contracted
             ,
             in
             going
             down
             from
             10
             to
             15
             fathom
             ,
             than
             in
             passing
             from
             5
             to
             10
             ;
             seing
             as
             they
             say
             ,
             the
             further
             down
             ,
             
             the
             cold
             is
             the
             greater
             ;
             and
             therefore
             the
             contraction
             of
             the
             Air
             must
             be
             the
             greater
             ;
             that
             's
             to
             say
             ,
             there
             must
             be
             more
             quantity
             of
             Air
             contracted
             in
             the
             one
             space
             ,
             than
             in
             the
             other
             .
             But
             so
             it
             is
             ,
             that
             the
             further
             down
             ,
             the
             contraction
             is
             the
             less
             .
             They
             judge
             likewise
             the
             coldness
             of
             the
             Water
             to
             be
             the
             cause
             ,
             why
             the
             sides
             of
             empty
             Vessels
             are
             broken
             in
             going
             down
             .
             But
             if
             this
             be
             ,
             then
             a
             strong
             Vessel
             should
             go
             no
             further
             down
             than
             a
             weak
             Vessel
             ;
             seing
             cold
             can
             pierce
             thorow
             the
             sides
             of
             the
             one
             ,
             as
             well
             as
             thorow
             the
             sides
             of
             the
             other
             .
             And
             why
             is
             it
             ,
             that
             a
             bladder
             full
             of
             wind
             will
             go
             down
             40
             or
             50
             fathom
             without
             bursting
             ,
             yea
             100
             ,
             and
             yet
             a
             stone-bottle
             or
             glass-bottle
             ,
             cannot
             go
             beyond
             20
             or
             30
             ?
             If
             cold
             have
             in
             it
             ,
             that
             power
             to
             break
             the
             sides
             of
             a
             strong
             bottle
             ,
             it
             must
             be
             far
             more
             able
             to
             burst
             the
             sides
             of
             a
             thin
             Bladder
             .
             This
             difference
             is
             clearly
             explicated
             from
             the
             Pressure
             of
             the
             Water
             ;
             but
             I
             defy
             any
             man
             to
             shew
             the
             difference
             from
             the
             coldness
             of
             it
             .
             'T
             is
             to
             be
             observed
             ,
             that
             in
             all
             such
             Experiments
             of
             sinking
             of
             Vessels
             ,
             as
             
               Hogs-heads
               ,
               Barrels
            
             ,
             and
             Bottles
             ,
             they
             must
             be
             closs
             on
             all
             sides
             .
             Therefore
             ,
             if
             a
             man
             desire
             to
             know
             ,
             how
             far
             down
             a
             Glass-bottle
             is
             able
             to
             go
             without
             bursting
             ,
             he
             must
             stop
             the
             mouth
             of
             it
             exactly
             ,
             with
             a
             piece
             of
             wood
             ,
             and
             cement
             .
          
           
             In
             setting
             down
             the
             dimensions
             of
             the
             Ark
             ,
             I
             have
             restricted
             them
             to
             40
             inches
             high
             ,
             and
             36
             inches
             wide
             .
             But
             if
             any
             man
             be
             desirous
             to
             enlarge
             them
             ,
             or
             make
             them
             less
             ,
             he
             may
             do
             it
             .
             Only
             't
             is
             to
             be
             observed
             ,
             that
             the
             larger
             the
             Ark
             be
             ,
             the
             Foot-stool
             that
             sinks
             it
             ,
             must
             be
             the
             heav●er
             .
             Yet
             it
             hath
             this
             advantage
             ,
             that
             it
             contains
             much
             Air
             ,
             which
             is
             the
             great
             perfection
             of
             it
             .
             One
             of
             a
             lesser
             size
             hath
             this
             advantage
             ,
             that
             it
             's
             more
             tractable
             ,
             and
             easier
             to
             let
             down
             ,
             and
             to
             be
             pull'd
             up
             .
             But
             these
             things
             are
             
             best
             known
             from
             Experience
             ,
             or
             if
             a
             man
             please
             ,
             he
             may
             calculate
             .
          
           
             As
             the
             Ark
             is
             a
             most
             useful
             device
             for
             profit
             ,
             so
             't
             is
             excellent
             for
             pleasure
             ,
             and
             recreation
             ,
             if
             a
             man
             were
             disposed
             to
             see
             the
             ground
             and
             channels
             of
             deep
             VVaters
             ,
             or
             were
             inclined
             to
             find
             out
             Hydrostatical
             conclusions
             ,
             a
             knowledge
             very
             profitable
             ,
             and
             which
             few
             have
             attained
             to
             .
             Though
             it
             seem
             somewhat
             difficult
             to
             enter
             the
             Ark
             ,
             and
             go
             down
             below
             the
             Water
             ,
             yet
             a
             little
             use
             will
             expell
             all
             fear
             .
             Then
             ,
             a
             man
             may
             go
             down
             with
             less
             hazard
             ,
             and
             fear
             in
             the
             Ark
             ,
             then
             in
             the
             Bell
             ,
             because
             he
             may
             conveniently
             fasten
             his
             hands
             ,
             to
             each
             side
             of
             the
             Ark
             ,
             if
             need
             were
             .
             He
             may
             conveniently
             sit
             ,
             as
             in
             a
             Chair
             ,
             all
             the
             time
             of
             down
             going
             ,
             and
             up-coming
             ,
             by
             fixing
             a
             little
             seat
             in
             it
             :
             he
             may
             have
             windows
             to
             look
             out
             at
             :
             his
             body
             may
             be
             so
             fixed
             ,
             that
             there
             needs
             be
             no
             fear
             of
             falling
             out
             .
          
           
             If
             a
             man
             were
             desirous
             to
             make
             Hydrostatical
             conclusions
             ,
             by
             Diving
             under
             the
             VVater
             ,
             the
             dimensions
             of
             the
             Ark
             might
             be
             enlarged
             ,
             so
             that
             it
             might
             conveniently
             cover
             a
             mans
             whole
             body
             ,
             by
             which
             means
             ,
             having
             much
             Air
             in
             it
             ,
             a
             Diver
             might
             continue
             under
             Water
             half
             a
             day
             ,
             if
             need
             were
             .
             Let
             us
             suppose
             then
             ,
             the
             hight
             of
             it
             to
             be
             8
             foot
             ,
             and
             the
             breadth
             3
             foot
             ,
             or
             more
             .
             In
             such
             a
             case
             ,
             a
             man
             might
             continue
             under
             the
             VVater
             many
             hours
             ;
             and
             yet
             not
             one
             part
             of
             his
             body
             wet
             :
             for
             if
             the
             Ark
             be
             8
             foot
             high
             ,
             and
             the
             man
             5
             foot
             in
             stature
             ,
             at
             the
             deepness
             of
             10
             fathom
             ,
             the
             Water
             can
             scarce
             rise
             3
             foot
             in
             it
             .
             But
             why
             may
             not
             a
             man
             come
             up
             every
             half
             hour
             ,
             when
             he
             finds
             difficulty
             to
             tarry
             down
             in
             a
             little
             Ark
             ?
             I
             answer
             ,
             he
             may
             ;
             but
             it
             's
             trouble
             and
             pains
             to
             pull
             him
             up
             ,
             and
             let
             him
             down
             so
             frequently
             .
             And
             it
             may
             so
             happen
             ,
             that
             through
             want
             of
             Air
             in
             a
             small
             Ark
             ,
             he
             be
             necessitated
             to
             come
             up
             
             before
             he
             end
             his
             work
             .
             And
             leaving
             the
             work
             imperfect
             ,
             he
             may
             find
             difficulty
             in
             the
             second
             down
             going
             ,
             to
             find
             sometimes
             the
             place
             where
             he
             was
             ,
             or
             the
             thing
             he
             was
             about
             to
             lift
             ,
             
               v.
               g.
            
             a
             chest
             of
             Gold.
             If
             it
             be
             said
             ,
             that
             a
             great
             weight
             of
             Stone
             or
             Lead
             is
             required
             to
             sink
             an
             Ark
             8
             foot
             high
             ,
             which
             will
             amount
             to
             4032
             pound
             weight
             .
             I
             answer
             ,
             't
             is
             so
             indeed
             :
             but
             here
             is
             the
             advantage
             ;
             when
             it
             is
             once
             below
             the
             Surface
             ,
             there
             's
             little
             more
             trouble
             ,
             then
             with
             an
             Ark
             of
             lesser
             dimensions
             ;
             because
             of
             the
             equipondium
             that's
             between
             it
             ,
             and
             the
             weight
             ,
             that
             sinks
             it
             .
          
           
             In
             such
             a
             Vessel
             many
             trials
             might
             be
             made
             .
             As
             first
             ,
             that
             of
             the
             Torricellian-Experiment
             ,
             which
             is
             nothing
             else
             ,
             but
             a
             Glass-Tub
             so
             many
             inches
             long
             ,
             with
             a
             Mercurial
             Cylinder
             in
             it
             of
             29
             inches
             high
             ,
             that
             's
             supposed
             to
             be
             kept
             up
             at
             that
             hight
             by
             the
             Pressure
             of
             the
             Air.
             If
             this
             were
             taken
             down
             about
             34
             foot
             ,
             't
             is
             very
             probable
             the
             Mercury
             would
             rise
             other
             29
             inches
             .
             The
             reason
             is
             ,
             because
             the
             Air
             within
             the
             Ark
             ,
             that
             presseth
             upon
             the
             Surface
             of
             the
             stagnant
             Mercury
             ,
             must
             be
             under
             as
             much
             pressure
             again
             ,
             as
             the
             Air
             above
             ;
             but
             the
             Air
             above
             ,
             is
             able
             to
             support
             29
             ;
             therefore
             this
             Air
             must
             sustain
             58.
             
             The
             reason
             why
             the
             Bensil
             is
             exactly
             doubled
             is
             this
             ,
             34
             foot
             of
             Water
             hath
             exactly
             as
             much
             Pressure
             in
             it
             ,
             as
             the
             whole
             element
             of
             Air
             ;
             therefore
             ,
             the
             Air
             within
             the
             Ark
             ,
             being
             34
             foot
             down
             ,
             must
             not
             only
             have
             in
             it
             the
             Pressure
             of
             the
             Air
             above
             ,
             but
             the
             Pressure
             of
             the
             Water
             likewise
             :
             this
             necessarily
             follows
             ,
             because
             when
             two
             Fluids
             touch
             ,
             or
             are
             contiguous
             to
             other
             ,
             the
             one
             cannot
             be
             under
             five
             degrees
             of
             Pressure
             ,
             unless
             the
             other
             be
             under
             as
             many
             .
             According
             to
             this
             reasoning
             ,
             if
             the
             Ark
             go
             down
             68
             foot
             ,
             the
             Mercury
             will
             rise
             from
             58
             to
             87.
             
             If
             to
             102
             ,
             it
             rises
             
             116.
             
             This
             reckoning
             is
             founded
             upon
             this
             ,
             namely
             that
             Water
             is
             14
             times
             lighter
             than
             Mercury
             ;
             and
             therefore
             one
             inch
             of
             Mercury
             requires
             14
             of
             Water
             to
             support
             it
             in
             a
             Tub
             ,
             and
             therefore
             ,
             before
             Water
             is
             able
             to
             raise
             29
             inches
             of
             it
             ,
             the
             Pipe
             must
             be
             34
             foot
             deep
             .
          
           
             For
             a
             second
             trial
             ,
             blow
             a
             Bladder
             as
             full
             of
             wind
             as
             it
             can
             hold
             ,
             and
             having
             knit
             the
             neck
             about
             with
             a
             Pack-threed
             ,
             place
             it
             in
             the
             Ark
             ,
             and
             you
             will
             find
             the
             sides
             ,
             that
             hath
             been
             stifly
             bended
             become
             flaccid
             and
             feeble
             ,
             as
             if
             the
             one
             half
             of
             the
             Wind
             had
             gone
             out
             ,
             and
             this
             will
             come
             to
             pass
             ,
             before
             the
             Ark
             can
             go
             down
             eight
             or
             nine
             fathom
             .
             The
             strong
             bensil
             of
             the
             Air
             within
             the
             Ark
             is
             the
             cause
             of
             this
             :
             for
             as
             the
             Ark
             goes
             down
             ,
             the
             Air
             grows
             stronger
             ,
             and
             so
             at
             length
             becomes
             of
             that
             power
             and
             force
             ,
             that
             it
             easily
             overcomes
             the
             force
             and
             Bensil
             of
             the
             Air
             of
             the
             Bladder
             ,
             and
             reducing
             it
             to
             less
             room
             ,
             causes
             the
             sides
             become
             flagging
             .
             In
             this
             case
             ,
             the
             said
             Air
             ,
             that
             was
             oval
             ,
             and
             had
             the
             form
             of
             the
             Bladder
             ,
             must
             become
             round
             in
             form
             of
             a
             Globe
             ,
             because
             of
             the
             uniform
             Pressure
             ,
             that
             it
             suffers
             from
             the
             Air
             of
             the
             Ark.
             When
             once
             the
             Ark
             is
             down
             14
             or
             15
             fathom
             ,
             take
             the
             same
             bladder
             ,
             and
             blow
             it
             stiff
             with
             Wind
             ,
             and
             knit
             the
             neck
             as
             afore
             .
             And
             you
             will
             find
             that
             in
             the
             up-coming
             ,
             the
             sides
             of
             it
             will
             burst
             asunder
             with
             a
             noise
             .
             When
             the
             Bladder
             is
             thus
             full
             of
             Wind
             ,
             't
             is
             supposed
             ,
             that
             there
             is
             a
             sort
             of
             counterpoise
             between
             it
             ,
             and
             the
             Air
             of
             the
             Ark.
             But
             as
             the
             Ark
             ascends
             ,
             the
             Air
             of
             it
             ,
             becomes
             weaker
             and
             weaker
             ,
             while
             in
             the
             mean
             time
             ,
             the
             Air
             of
             the
             Bladder
             suffers
             no
             relaxation
             ;
             therefore
             ,
             when
             the
             Ark
             comes
             near
             the
             surface
             ,
             there
             arises
             a
             great
             disproportion
             between
             the
             one
             Air
             and
             the
             other
             ,
             as
             to
             strength
             ,
             and
             therefore
             the
             Air
             of
             the
             Bladder
             being
             the
             strongest
             ,
             rents
             the
             sides
             
             in
             pieces
             ,
             and
             comes
             out
             with
             a
             noise
             .
             Or
             ,
             blow
             it
             but
             half
             full
             of
             wind
             ,
             and
             you
             will
             find
             before
             ,
             the
             Ark
             come
             near
             to
             the
             top
             ,
             the
             said
             Bladder
             to
             be
             bended
             to
             the
             full
             .
          
           
             For
             a
             third
             trial
             ,
             take
             a
             Glass
             ,
             such
             as
             they
             use
             in
             Caves
             ,
             for
             preserving
             of
             Brandy
             ,
             and
             stopping
             the
             mouth
             closely
             ,
             take
             it
             down
             with
             you
             in
             the
             Ark
             ;
             and
             you
             will
             see
             ,
             the
             sides
             of
             it
             break
             in
             pieces
             ,
             before
             you
             go
             down
             four
             or
             five
             fathom
             .
             The
             strong
             Bensil
             of
             the
             ambient
             Air
             ,
             is
             the
             cause
             of
             this
             .
             If
             you
             take
             it
             down
             with
             the
             orifice
             open
             ,
             no
             hurt
             shall
             befal
             it
             .
             Or
             if
             you
             stop
             the
             orifice
             in
             the
             up-coming
             ,
             you
             will
             find
             the
             same
             hurt
             come
             to
             it
             .
             But
             here
             is
             the
             difference
             ,
             in
             the
             first
             bursting
             ,
             the
             sides
             are
             prest
             inward
             ,
             by
             the
             ambient
             Air
             ;
             in
             the
             second
             ,
             the
             sides
             are
             prest
             outward
             ,
             by
             the
             Air
             within
             the
             Glass
             .
          
           
             For
             a
             fourth
             trial
             ,
             take
             a
             round
             Glass-bottle
             ,
             pretty
             strong
             in
             the
             sides
             ,
             and
             when
             it
             is
             down
             with
             you
             in
             the
             Ark
             14
             or
             15
             fathom
             ,
             stop
             the
             mouth
             of
             it
             exactly
             ,
             and
             when
             it
             comes
             above
             ,
             you
             will
             find
             a
             considerable
             quantity
             of
             Wind
             come
             out
             of
             it
             ,
             when
             the
             orifice
             is
             opened
             .
             This
             evidently
             demonstrats
             ,
             that
             the
             Air
             within
             the
             Ark
             ,
             12
             ,
             13
             ,
             or
             14
             fathom
             down
             ,
             is
             under
             a
             far
             stronger
             Bensil
             then
             the
             Air
             above
             .
          
           
             For
             a
             fifth
             trial
             ,
             let
             a
             man
             apply
             to
             his
             skin
             a
             cold
             Cupping-Glass
             ,
             when
             he
             enters
             the
             Ark
             ;
             and
             he
             will
             find
             such
             a
             swelling
             arise
             within
             it
             ,
             as
             when
             it
             is
             applied
             hot
             by
             a
             Chyrurgion
             .
             This
             tumor
             begins
             to
             rise
             ,
             assoon
             as
             the
             Ark
             begins
             to
             go
             down
             .
             The
             reason
             is
             evident
             from
             unequal
             Pressure
             ,
             the
             parts
             within
             the
             Glass
             being
             less
             prest
             ,
             than
             the
             parts
             without
             .
          
           
             For
             a
             sixth
             trial
             ,
             take
             a
             common
             Weather-Glass
             ,
             and
             
             Place
             it
             in
             the
             Ark
             ,
             and
             in
             the
             going
             down
             ,
             you
             will
             see
             the
             liquor
             creep
             up
             in
             it
             ,
             by
             degrees
             ,
             as
             the
             Ark
             goes
             down
             ,
             as
             if
             some
             extraordinary
             cold
             ,
             were
             the
             cause
             of
             it
             .
             And
             as
             the
             Ark
             comes
             up
             by
             degrees
             ,
             the
             said
             liquor
             creeps
             down
             by
             degrees
             .
             The
             cause
             of
             this
             Phenomenon
             is
             not
             cold
             ,
             as
             some
             might
             judge
             ,
             but
             the
             strong
             Bensil
             of
             the
             Air
             within
             the
             Ark
             ,
             that
             so
             presseth
             upon
             the
             surface
             of
             the
             stagnant
             Water
             ,
             that
             it
             drives
             it
             up
             .
             If
             you
             take
             with
             you
             ,
             a
             
               Weather-Glass
               ,
               hermetically
            
             sealled
             ,
             no
             such
             thing
             will
             follow
             ;
             because
             the
             outward
             Pressure
             is
             keeped
             off
             .
             'T
             is
             not
             then
             cold
             ,
             that
             's
             the
             cause
             ,
             but
             weight
             .
             By
             the
             way
             take
             notice
             ,
             that
             all
             common
             Weather-Glases
             are
             fallacious
             and
             deceitful
             ;
             because
             the
             motion
             of
             the
             Water
             in
             them
             ,
             is
             not
             only
             caused
             by
             heat
             ,
             but
             by
             the
             weight
             of
             the
             Air
             ,
             which
             sometimes
             is
             more
             ,
             and
             sometimes
             less
             ,
             as
             frequently
             I
             have
             observed
             ,
             and
             as
             hath
             been
             observed
             by
             others
             .
             This
             difference
             is
             found
             ,
             by
             the
             alteration
             of
             the
             altitude
             of
             the
             Mercurial
             cylinder
             ,
             in
             the
             Baroscope
             ,
             which
             is
             more
             and
             less
             ,
             as
             the
             Pressure
             of
             the
             Air
             changeth
             .
             In
             fair
             weather
             ,
             and
             before
             it
             comes
             ,
             the
             Mercury
             creeps
             up
             .
             In
             foul
             and
             rainy
             weather
             ,
             and
             a
             pretty
             while
             ,
             before
             it
             fall
             out
             ,
             it
             creeps
             down
             .
             Because
             in
             fair
             weather
             ,
             the
             weight
             of
             the
             Air
             is
             more
             ,
             than
             in
             rainy
             and
             dirty
             weather
             .
             December
             ,
             13.
             1669.
             
             I
             found
             the
             altitude
             29
             inches
             ,
             and
             nine
             ten
             parts
             of
             an
             inch
             :
             at
             this
             time
             the
             heavens
             were
             covered
             with
             dry
             and
             thick
             clouds
             ,
             and
             no
             rain
             followed
             .
             March
             26.
             1670.
             
             I
             found
             the
             altitude
             no
             more
             ,
             than
             27
             inches
             ,
             and
             nine
             ten
             parts
             ,
             at
             which
             time
             ,
             there
             was
             a
             strong
             Wind
             with
             rain
             .
             Between
             these
             two
             termes
             of
             altitude
             ,
             I
             have
             found
             the
             Mercury
             move
             near
             a
             twelve
             moneth
             .
             'T
             is
             a
             most
             sure
             prognosticator
             ,
             for
             if
             after
             
             rain
             ,
             you
             find
             the
             Mercury
             creep
             up
             in
             the
             morning
             ,
             you
             may
             be
             sure
             ,
             all
             the
             day
             following
             will
             be
             fair
             ,
             notwithstanding
             that
             the
             heavens
             threateneth
             otherwayes
             .
             If
             after
             fair
             weather
             ,
             the
             Mercury
             subside
             ,
             and
             fall
             down
             a
             little
             ,
             you
             may
             be
             sure
             of
             rain
             within
             a
             short
             time
             ,
             though
             no
             appearance
             be
             ,
             in
             the
             present
             .
             It
             falls
             down
             likewise
             ,
             when
             winds
             do
             blow
             .
             What
             the
             true
             cause
             is
             ,
             why
             there
             is
             such
             an
             alteration
             in
             the
             Pressure
             of
             the
             Air
             ,
             before
             foul
             weather
             ,
             and
             fair
             ,
             and
             in
             the
             time
             of
             it
             ,
             it
             is
             not
             easie
             to
             determine
             .
          
           
             But
             we
             proceed
             .
             Trial
             likewise
             might
             be
             made
             ,
             by
             fiting
             a
             great
             piece
             of
             Ordnance
             above
             ,
             whether
             the
             report
             would
             be
             heard
             below
             the
             Water
             or
             not
             ?
             This
             would
             determine
             the
             question
             ,
             whether
             Water
             be
             a
             fit
             medium
             for
             conveying
             sound
             as
             Air
             is
             .
             Item
             ,
             whether
             or
             not
             ,
             the
             Sea
             water
             be
             fresher
             at
             the
             bottom
             ,
             than
             near
             the
             top
             ,
             which
             is
             affirmed
             by
             some
             .
             Item
             ,
             whether
             sounds
             be
             as
             distinct
             in
             such
             a
             small
             portion
             of
             Air
             ,
             as
             they
             are
             above
             .
             This
             might
             be
             tried
             with
             a
             Bell
             of
             a
             Watch.
             If
             need
             were
             ,
             a
             little
             chamber
             Bell
             might
             be
             hung
             within
             the
             Ark
             ,
             and
             a
             small
             chord
             might
             pass
             up
             from
             it
             ,
             through
             the
             cover
             ,
             whereby
             the
             persons
             above
             ,
             might
             by
             so
             many
             tingles
             ,
             speak
             such
             and
             such
             words
             to
             the
             Diver
             .
             I
             have
             demonstrated
             before
             ,
             that
             though
             there
             were
             a
             little
             narrow
             hole
             made
             in
             the
             cover
             above
             ,
             yet
             neither
             Air
             would
             go
             out
             ,
             nor
             Water
             come
             in
             .
             If
             a
             man
             were
             curious
             ,
             he
             might
             have
             a
             window
             not
             only
             in
             the
             sides
             ,
             but
             in
             the
             roof
             above
             ,
             covered
             with
             a
             piece
             of
             pure
             thin
             Glass
             ,
             thorow
             which
             he
             might
             look
             up
             ,
             after
             he
             is
             down
             two
             or
             three
             fathom
             ,
             and
             see
             whether
             there
             appeared
             any
             alteration
             in
             the
             dimensions
             of
             the
             body
             of
             Sun
             or
             not
             ,
             or
             seemed
             nearer
             .
          
           
        
         
           
           
             EXPERIMENT
             XIX
             .
             Figure
             26.
             
          
           
             THis
             Figure
             represents
             a
             deep
             Water
             ,
             whose
             first
             and
             visible
             surface
             ,
             is
             F
             G.
             The
             imaginary
             surface
             ,
             is
             E
             L
             C
             ,
             34
             foot
             below
             it
             .
             A
             D
             B
             is
             a
             Siphon
             ,
             working
             below
             this
             VVater
             with
             Mercury
             .
             A
             E
             L
             is
             a
             Vessel
             with
             stagnant
             Mercury
             ,
             among
             which
             the
             orifice
             A
             is
             drowned
             ,
             the
             other
             orifice
             B
             existing
             among
             the
             Water
             ,
             D
             M
             is
             the
             hight
             of
             the
             Siphon
             above
             the
             line
             of
             level
             ,
             which
             I
             suppose
             is
             58
             inches
             .
             For
             making
             it
             work
             ,
             stop
             the
             two
             orifices
             closely
             ,
             and
             pour
             in
             as
             much
             Mercury
             at
             a
             hole
             made
             at
             D
             ,
             as
             will
             fill
             both
             the
             legs
             .
             Then
             stopping
             the
             said
             hole
             ,
             open
             the
             two
             orifices
             A
             and
             B
             ,
             and
             you
             will
             find
             the
             liquor
             run
             as
             long
             out
             at
             B
             ,
             as
             there
             is
             any
             almost
             in
             the
             vessel
             A
             E
             L.
             For
             evincing
             this
             ,
             which
             is
             the
             only
             difficulty
             ,
             consider
             ,
             that
             if
             this
             Siphon
             ,
             were
             filled
             with
             Water
             ,
             and
             made
             to
             work
             only
             with
             Air
             ,
             (
             as
             is
             clear
             from
             daily
             experience
             )
             the
             liquor
             would
             run
             out
             constantly
             at
             B.
             Because
             there
             is
             here
             an
             unequal
             Pressure
             ;
             the
             surface
             of
             Air
             N
             B
             ,
             being
             more
             burdened
             ,
             than
             the
             surface
             E
             L
             C
             ,
             but
             where
             unequal
             Pressure
             is
             in
             Fluids
             (
             according
             to
             the
             12th
             Theorem
             )
             motion
             must
             follow
             ,
             I
             prove
             the
             surface
             N
             B
             to
             be
             more
             burdened
             ,
             than
             the
             surface
             E
             L
             C
             ,
             because
             the
             Water
             B
             D
             ,
             is
             heavier
             than
             the
             Water
             L
             D
             ,
             as
             is
             evident
             to
             the
             eye
             .
             The
             Air
             B
             therefore
             ,
             sustaining
             far
             more
             weight
             ,
             than
             the
             Air
             E
             L
             ,
             must
             cede
             and
             yeeld
             .
             Next
             ,
             there
             is
             here
             a
             pondus
             and
             a
             potentia
             ,
             the
             pondus
             is
             the
             VVater
             L
             D
             ;
             the
             potentia
             by
             which
             it
             is
             counterpoised
             ,
             is
             the
             Water
             B
             D
             ;
             but
             these
             are
             unequal
             ,
             B
             D
             being
             
             heavier
             ,
             than
             L
             D
             ;
             therefore
             according
             to
             the
             33
             Theorem
             ,
             these
             two
             Fluids
             cannot
             cease
             from
             motion
             .
             If
             it
             be
             said
             ,
             that
             the
             surface
             N
             B
             is
             stronger
             ,
             than
             the
             surface
             E
             L
             C
             ,
             seing
             it
             is
             lower
             .
             I
             answer
             ,
             the
             difference
             is
             so
             unsensible
             ,
             that
             they
             may
             be
             judged
             but
             one
             .
             Now
             ,
             I
             say
             ,
             if
             this
             Siphon
             work
             in
             Air
             ,
             with
             Water
             ,
             it
             must
             likewise
             ,
             work
             in
             Water
             with
             Mercury
             .
             Therefore
             ,
             this
             Siphon
             being
             34
             foot
             below
             the
             first
             surface
             F
             G
             ,
             the
             liquor
             must
             run
             out
             constantly
             at
             B.
             Because
             ,
             there
             is
             here
             ,
             an
             unequal
             Pressure
             ,
             the
             surface
             of
             VVater
             N
             B
             ,
             be●ng
             more
             burdened
             ,
             than
             the
             surface
             E
             L
             C.
             Though
             there
             be
             more
             weight
             in
             N
             B
             ,
             than
             in
             E
             L
             C
             ,
             because
             it
             is
             lower
             ,
             yet
             because
             the
             difference
             is
             not
             so
             much
             ,
             as
             is
             between
             the
             weight
             of
             B
             D
             ,
             and
             the
             weight
             of
             L
             D
             ,
             it
             proves
             nothing
             .
             Note
             here
             ,
             that
             so
             long
             as
             D
             ,
             is
             within
             58
             inches
             of
             E
             L
             C
             ,
             this
             Siphon
             will
             work
             .
             The
             reason
             is
             ,
             because
             the
             Pressure
             of
             34
             foot
             of
             VVater
             ,
             with
             the
             Pressure
             of
             the
             Air
             ,
             upon
             F
             G
             ,
             are
             able
             to
             raise
             Mercury
             exactly
             58
             inches
             .
             But
             if
             D
             exceed
             that
             hight
             ,
             no
             Art
             will
             make
             the
             liquor
             run
             out
             at
             B.
             Note
             secondly
             ,
             that
             this
             Siphon
             will
             operate
             with
             Air
             and
             VVater
             ,
             though
             the
             top
             D
             were
             34
             foot
             above
             M
             ;
             and
             the
             reason
             is
             ,
             because
             the
             Pressure
             of
             the
             Air
             ,
             is
             able
             to
             raise
             a
             pillar
             of
             Water
             to
             that
             hight
             .
             Note
             thirdly
             ,
             that
             if
             there
             were
             an
             orifice
             opened
             at
             C
             ,
             upon
             the
             level
             line
             E
             L
             C
             ,
             the
             two
             Waters
             would
             become
             of
             the
             same
             weight
             ,
             the
             one
             not
             being
             able
             to
             move
             the
             other
             .
             If
             you
             bore
             a
             hole
             at
             R
             ,
             the
             liquor
             ascends
             from
             R
             to
             D
             ,
             and
             goeth
             down
             from
             D
             to
             A
             ,
             and
             so
             the
             motion
             ends
             .
             But
             ,
             if
             the
             leg
             A
             D
             were
             six
             times
             wider
             ,
             than
             B
             D
             ,
             the
             liquor
             would
             not
             run
             out
             at
             B.
             I
             shall
             answer
             this
             in
             the
             close
             .
          
           
             From
             this
             Experiment
             we
             see
             first
             ,
             that
             the
             motion
             of
             
             Fluid
             Bodies
             up
             thorow
             Pumps
             ,
             and
             Siphons
             is
             not
             for
             shuning
             vacuity
             ,
             but
             because
             they
             are
             prest
             up
             violently
             .
             We
             see
             next
             ,
             that
             when
             the
             Pressure
             is
             uniform
             ,
             there
             is
             no
             motion
             in
             Fluids
             ;
             but
             assoon
             ,
             as
             one
             part
             is
             more
             prest
             ,
             than
             another
             ,
             motion
             begins
             :
             because
             ,
             this
             Siphon
             will
             not
             operate
             ,
             if
             the
             orifice
             be
             made
             in
             C
             ;
             but
             if
             so
             be
             ,
             it
             be
             in
             D
             ,
             then
             the
             motion
             begins
             ;
             because
             there
             is
             here
             an
             unequal
             Pressure
             ,
             which
             was
             not
             in
             the
             other
             .
             We
             see
             thirdly
             ,
             that
             Fluids
             have
             a
             determinate
             Sphere
             of
             activity
             ,
             to
             which
             they
             are
             able
             to
             press
             ,
             and
             no
             further
             :
             because
             this
             Water
             ,
             is
             not
             able
             to
             press
             Mercury
             higher
             than
             58
             inches
             .
             So
             the
             Air
             cannot
             raise
             Water
             higher
             than
             34
             foot
             .
             If
             this
             Water
             were
             68
             foot
             deep
             ,
             the
             Sphere
             of
             it's
             activity
             would
             be
             116
             inches
             .
             We
             see
             fourthly
             ,
             that
             in
             Fluids
             there
             is
             a
             Pondus
             and
             a
             Potentia
             ;
             and
             that
             the
             inequality
             of
             weight
             between
             the
             two
             ,
             is
             the
             only
             cause
             of
             motion
             .
             We
             see
             fifthly
             ,
             that
             as
             long
             as
             this
             inequality
             of
             weight
             continues
             ,
             as
             long
             continues
             the
             motion
             ,
             because
             ,
             as
             long
             as
             B
             D
             ,
             is
             heavier
             than
             L
             D
             ,
             the
             motion
             perseveres
             .
             We
             see
             sixthly
             ,
             the
             possibility
             of
             a
             
               perpetual
               motion
            
             in
             Fluids
             ;
             because
             the
             liquor
             runs
             perpetually
             out
             at
             B.
             If
             it
             be
             said
             ,
             the
             motion
             ends
             ,
             when
             the
             stagnant
             Mercury
             A
             E
             L
             faileth
             .
             I
             answer
             ,
             this
             stop
             is
             only
             accidental
             ,
             and
             not
             essentially
             from
             the
             nature
             of
             Fluids
             .
             If
             it
             be
             enquired
             ,
             whether
             or
             not
             ,
             would
             the
             Mercury
             run
             out
             at
             B
             ,
             upon
             supposition
             ,
             the
             shank
             L
             D
             were
             twice
             as
             wide
             ,
             as
             the
             shank
             B
             D
             ?
             I
             answer
             it
             would
             .
             If
             it
             be
             said
             that
             the
             one
             is
             far
             heavier
             than
             the
             other
             ,
             namely
             L
             D
             than
             D
             B.
             I
             answer
             ,
             weight
             in
             Fluids
             is
             not
             counted
             according
             to
             thickness
             ,
             but
             according
             to
             altitude
             .
          
        
         
           
           
             EXPERIMENT
             XX.
             Figure
             27.
             
          
           
             THis
             last
             is
             for
             demonstrating
             the
             precise
             and
             just
             weight
             of
             any
             Pillar
             of
             Air
             ,
             Water
             ,
             Mercury
             ,
             or
             of
             any
             other
             Fluid
             body
             ,
             if
             some
             of
             their
             dimensions
             ,
             be
             but
             once
             knowen
             .
             A
             B
             then
             is
             a
             square
             Pipe
             12
             foot
             high
             ,
             and
             six
             inches
             in
             wideness
             ,
             full
             of
             Water
             ,
             resting
             upon
             the
             surface
             of
             Air
             A
             C.
             And
             E
             G
             is
             a
             square
             Pipe
             12
             foot
             high
             ,
             and
             12
             inches
             wide
             ,
             full
             of
             VVater
             ,
             resting
             upon
             the
             surface
             of
             Air
             E
             F.
             None
             needs
             to
             doubt
             ,
             but
             the
             two
             Waters
             ,
             will
             be
             suspended
             after
             this
             manner
             ,
             even
             though
             the
             orifices
             A
             and
             E
             were
             downward
             ,
             especially
             if
             they
             be
             guarded
             with
             Water
             ,
             but
             the
             demonstrations
             ,
             will
             be
             the
             more
             evident
             ,
             that
             wee
             suppose
             the
             two
             Pillars
             of
             Water
             to
             be
             suspended
             as
             they
             are
             .
             From
             this
             Experiment
             I
             say
             first
             ,
             that
             the
             Pillar
             of
             Air
             C
             D
             is
             168
             pound
             weight
             ,
             at
             least
             ;
             which
             I
             prove
             thus
             .
             The
             VVater
             A
             B
             is
             168
             pound
             :
             therefore
             the
             Air
             C
             D
             ,
             must
             be
             as
             much
             .
             I
             prove
             the
             Antecedent
             ,
             because
             it
             's
             a
             Pillar
             of
             VVater
             12
             foot
             high
             ,
             and
             six
             inches
             thick
             :
             but
             every
             half
             cubical
             foot
             of
             VVater
             ,
             that
             containes
             216
             inches
             ,
             weighs
             seven
             pound
             :
             therefore
             seing
             the
             Pillar
             is
             12
             foot
             ,
             it
             must
             contain
             24
             half
             feet
             ;
             but
             24
             times
             7
             is
             168.
             
             The
             only
             difficulty
             is
             to
             prove
             the
             Connexion
             ,
             which
             I
             do
             thus
             ,
             from
             the
             seventh
             Theor.
             
               all
               the
               parts
               of
               a
               Fluid
               in
               the
               same
               Horizontal
               line
               ,
               are
               equally
               prest
               ,
            
             but
             so
             it
             is
             ,
             that
             the
             part
             A
             ,
             and
             the
             part
             C
             ,
             are
             in
             the
             same
             horizontal
             surface
             ;
             therefore
             the
             part
             A
             ,
             and
             the
             part
             C
             ,
             are
             equally
             prest
             .
             But
             if
             the
             part
             A
             ,
             and
             the
             part
             C
             ,
             be
             equally
             prest
             ,
             the
             Pillar
             of
             Air
             C
             D
             ,
             must
             be
             as
             heavy
             ,
             as
             the
             
             Pillar
             of
             VVater
             A
             B.
             I
             say
             secondly
             ,
             that
             the
             Pillar
             of
             Air
             F
             H
             ,
             weighs
             672
             pound
             ,
             I
             prove
             it
             thus
             .
             The
             Water
             E
             G
             weighs
             672
             pound
             ;
             therefore
             the
             Air
             F
             H
             ,
             weighs
             as
             much
             .
             The
             Antecedent
             is
             clear
             ,
             because
             E
             G
             ,
             is
             a
             square
             Pillar
             of
             VVater
             12
             foot
             high
             ,
             and
             12
             inches
             thick
             ;
             but
             every
             cubical
             foot
             of
             VVater
             weighs
             56
             pound
             :
             but
             12
             times
             56
             ,
             is
             672.
             
             I
             prove
             the
             connexion
             ,
             as
             before
             .
             All
             the
             parts
             of
             an
             horizontal
             surface
             ,
             are
             equally
             prest
             ;
             therefore
             the
             part
             F
             ,
             must
             sustain
             as
             much
             burden
             ,
             as
             the
             part
             E.
             
          
           
             To
             proceed
             a
             little
             further
             ,
             let
             us
             suppose
             the
             Pipe
             A
             B
             to
             be
             34
             foot
             high
             ,
             and
             the
             Pipe
             E
             G
             to
             be
             as
             much
             .
             I
             assert
             then
             thirdly
             ,
             the
             Pillar
             of
             Air
             C
             D
             to
             weigh
             476
             pound
             ,
             which
             I
             prove
             as
             before
             .
             All
             the
             parts
             of
             the
             same
             surface
             ,
             are
             burdened
             with
             the
             like
             weight
             ,
             but
             the
             part
             A
             sustains
             476
             pound
             ,
             therefore
             the
             part
             C
             must
             support
             as
             much
             .
             The
             Connexion
             is
             evident
             ,
             and
             the
             Antecedent
             is
             so
             too
             ,
             because
             the
             VVater
             A
             B
             being
             34
             foot
             high
             ,
             and
             six
             inches
             thick
             ,
             must
             weigh
             476
             pound
             :
             for
             ,
             if
             216
             inches
             ,
             weigh
             seven
             pound
             ,
             14688
             inches
             ,
             must
             weigh
             476
             pound
             .
             I
             assert
             fourthly
             ,
             the
             Pillar
             of
             Air
             F
             H
             to
             weigh
             1904
             pound
             ,
             which
             I
             demonstrat
             by
             the
             former
             Medium
             .
             All
             the
             parts
             of
             a
             Fluid
             that
             ly
             in
             the
             same
             horizontal
             surface
             ,
             are
             equally
             prest
             ;
             but
             so
             it
             is
             ,
             that
             E
             and
             F
             ,
             do
             so
             ly
             ;
             therefore
             F
             must
             be
             as
             much
             burdened
             as
             E
             ;
             the
             Water
             therefore
             E
             G
             ,
             weighing
             1904
             pound
             ,
             the
             Air
             F
             H
             ,
             must
             weigh
             as
             much
             .
             For
             if
             216
             inches
             of
             Water
             weigh
             seven
             pound
             ,
             58752
             inches
             (
             for
             so
             many
             are
             in
             the
             Water
             E
             G
             )
             must
             weigh
             1904
             pound
             .
          
           
             Let
             us
             suppose
             secondly
             ,
             the
             Tub
             A
             B
             to
             be
             only
             29
             inches
             high
             ,
             and
             the
             Tub
             E
             G
             ,
             of
             the
             same
             hight
             ,
             and
             
             that
             six
             inches
             wide
             ,
             and
             this
             12
             inches
             wide
             .
             I
             affirm
             then
             fifthly
             ,
             the
             Air
             C
             D
             to
             weigh
             yet
             476
             pound
             ,
             and
             the
             Air
             F
             H
             ,
             to
             weigh
             1904
             pound
             .
             Because
             the
             Pillar
             of
             Mercury
             A
             B
             ,
             weighs
             476
             pound
             ,
             and
             the
             Pillar
             of
             Mercury
             E
             G
             ,
             weighs
             1904
             pound
             :
             therefore
             ,
             if
             A
             B
             be
             476
             ,
             C
             D
             must
             be
             as
             much
             .
             And
             if
             E
             G
             be
             1904
             ;
             F
             H
             ,
             must
             be
             of
             the
             same
             weight
             .
             I
             prove
             the
             Mercury
             A
             B
             to
             weigh
             about
             476
             pound
             ,
             though
             it
             be
             but
             29
             inches
             high
             ;
             because
             it
             is
             14
             times
             heavier
             than
             Water
             .
             For
             the
             same
             cause
             ,
             doth
             the
             Mercury
             E
             G
             weigh
             about
             1904
             pound
             .
             I
             say
             about
             ,
             because
             34
             foot
             ,
             containes
             29
             inches
             ,
             more
             than
             14
             times
             .
          
           
             Let
             it
             be
             supposed
             thirdly
             ,
             the
             Pipe
             E
             G
             ,
             (
             being
             34
             foot
             high
             ,
             )
             to
             have
             the
             one
             half
             of
             it
             I
             G
             ,
             full
             of
             Air
             ,
             and
             the
             other
             half
             E
             K
             full
             of
             VVater
             ,
             I
             affirm
             then
             sixthly
             ,
             the
             part
             E
             ,
             and
             the
             part
             F
             ,
             to
             be
             yet
             equally
             burdened
             .
             That
             's
             to
             say
             ,
             the
             VVater
             E
             K
             ,
             that
             's
             now
             but
             17
             foot
             ,
             makes
             as
             great
             a
             Pressure
             upon
             E
             ,
             as
             when
             it
             was
             34
             foot
             .
             The
             reason
             of
             this
             ,
             is
             surely
             the
             Pressure
             of
             the
             Air
             I
             G
             ,
             that
             bears
             down
             the
             Water
             K
             E
             ,
             with
             the
             weight
             of
             952
             pound
             ,
             the
             half
             of
             1904
             pound
             .
             If
             it
             be
             said
             according
             to
             the
             Theorem
             21
             ,
             that
             there
             is
             as
             much
             Pressure
             and
             weight
             in
             the
             least
             part
             of
             a
             Fluid
             ,
             as
             in
             the
             whole
             ;
             therefore
             the
             Air
             I
             G
             ,
             must
             be
             as
             heavy
             as
             E
             H.
             I
             answer
             I
             G
             ,
             is
             not
             so
             heavy
             as
             F
             H
             ,
             because
             the
             Water
             E
             K
             impending
             in
             the
             lower
             part
             of
             the
             Tub
             ,
             hath
             occasioned
             the
             Air
             I
             G
             ,
             to
             expand
             it self
             so
             many
             inches
             ,
             by
             which
             means
             ,
             it
             loseth
             so
             many
             degrees
             of
             it's
             Bensil
             .
             If
             you
             remove
             the
             Water
             E
             K
             ,
             then
             will
             the
             Air
             I
             G
             ,
             be
             as
             heavy
             ,
             as
             F
             H
             ;
             because
             E
             K
             being
             Air
             ,
             it
             reduceth
             I
             G
             to
             that
             same
             degree
             of
             Bensil
             with
             it self
             ;
             but
             when
             the
             Air
             E
             is
             burdened
             with
             the
             Water
             E
             K
             ,
             it
             cannot
             
             make
             the
             Air
             I
             G
             ,
             of
             that
             same
             weight
             with
             it self
             .
          
           
             Let
             us
             suppose
             fourthly
             ,
             that
             only
             eight
             foot
             and
             an
             half
             of
             Water
             ,
             are
             in
             the
             Tub
             ,
             namely
             between
             E
             and
             N.
             I
             say
             then
             seventhly
             ,
             that
             the
             part
             E
             ,
             is
             as
             much
             burdened
             with
             it
             ,
             as
             when
             the
             Pipe
             was
             full
             ;
             because
             the
             25
             foot
             ,
             and
             an
             half
             of
             Air
             N
             G
             ,
             is
             exactly
             as
             heavy
             ,
             as
             the
             25
             foot
             and
             an
             half
             of
             the
             Water
             that
             's
             gone
             .
             I
             prove
             it
             thus
             .
             The
             Air
             E
             hath
             the
             weight
             of
             1904
             pound
             in
             it self
             ,
             seing
             the
             weight
             of
             the
             surface
             ,
             is
             alwayes
             equal
             to
             the
             weight
             of
             the
             Pillar
             ,
             but
             being
             burdened
             with
             the
             VVater
             E
             N
             ,
             that
             weighs
             476
             pound
             ,
             it
             cannot
             press
             up
             with
             more
             weight
             then
             with
             1428
             pound
             :
             and
             therefore
             the
             top
             of
             the
             Water
             N
             ,
             must
             press
             upon
             the
             under
             part
             of
             the
             Air
             ,
             that
             's
             contiguous
             with
             it
             ,
             with
             1428.
             
             If
             this
             be
             ,
             the
             Air
             N
             G
             ,
             must
             press
             down
             with
             as
             much
             ,
             seing
             according
             to
             the
             20
             Theorem
             ,
             it
             is
             impossible
             ,
             that
             one
             part
             of
             a
             Fluid
             ,
             can
             be
             under
             Pressure
             ,
             unless
             the
             next
             adjacent
             part
             ,
             be
             under
             the
             same
             degree
             of
             Pressure
             .
             Therefore
             I
             conclude
             ,
             that
             the
             25
             foot
             and
             an
             half
             of
             Air
             N
             G
             ,
             is
             as
             heavy
             ,
             as
             the
             25
             foot
             and
             an
             half
             of
             the
             Water
             that
             's
             gone
             .
             This
             makes
             it
             evident
             also
             ,
             that
             when
             the
             Pipe
             is
             half
             full
             of
             VVater
             ,
             as
             E
             K
             ,
             the
             Air
             I
             G
             ,
             hath
             the
             weight
             of
             952
             pound
             .
             Because
             E
             being
             in
             it self
             1904
             ,
             but
             being
             burdened
             with
             E
             K
             952
             ,
             it
             cannot
             make
             the
             top
             of
             the
             Water
             K
             ,
             press
             upon
             I
             with
             more
             weight
             than
             952
             ;
             and
             therefore
             (
             by
             the
             20
             Theorem
             ,
             )
             the
             Air
             G
             I
             ,
             must
             weigh
             952
             likewise
             .
          
           
             I
             affirm
             eighthly
             ,
             that
             ,
             when
             the
             Pipe
             is
             full
             of
             Water
             ,
             from
             E
             to
             G
             ,
             if
             a
             man
             poise
             it
             in
             his
             hand
             ,
             he
             doth
             not
             find
             the
             weight
             of
             the
             Water
             E
             G.
             And
             the
             reason
             is
             ,
             because
             it
             's
             sustained
             by
             the
             part
             of
             the
             surface
             E.
             But
             if
             the
             Air
             E
             sustain
             it
             ,
             my
             hand
             cannot
             sustain
             it
             .
             I
             find
             
             then
             only
             the
             weight
             of
             the
             Tub
             ,
             but
             not
             the
             weight
             of
             the
             VVater
             within
             it
             .
             I
             say
             ninthly
             ,
             that
             when
             I
             poise
             the
             said
             Tub
             ,
             I
             find
             the
             whole
             weight
             of
             the
             Pillar
             of
             Air
             L
             M
             ,
             which
             is
             exactly
             1904
             pound
             .
             I
             prove
             it
             thus
             .
             The
             pondus
             of
             a
             Fluid
             is
             then
             only
             found
             ,
             when
             there
             is
             not
             a
             potentia
             to
             counterpoise
             it
             ,
             or
             at
             least
             ,
             when
             the
             potentia
             is
             inferior
             to
             the
             pondus
             :
             but
             there
             is
             here
             no
             potentia
             ,
             counterpoising
             the
             pondus
             of
             the
             Air
             L
             M.
             Therefore
             ,
             I
             must
             find
             the
             weight
             of
             it
             ,
             when
             I
             lift
             up
             the
             Tub.
             The
             
               major
               proposition
            
             is
             clear
             from
             the
             tenth
             Theorem
             .
             It
             's
             evident
             also
             ,
             from
             common
             experience
             ;
             for
             while
             a
             ballance
             is
             hanging
             upon
             a
             nail
             ,
             with
             six
             pound
             in
             the
             one
             scale
             ,
             and
             nothing
             in
             the
             other
             ,
             you
             will
             find
             the
             whole
             burden
             ,
             if
             you
             press
             up
             that
             one
             scale
             with
             the
             palm
             of
             your
             hand
             .
             But
             if
             so
             be
             ,
             there
             were
             six
             pound
             in
             the
             opposite
             scale
             ,
             you
             will
             not
             find
             the
             first
             six
             ;
             and
             the
             reason
             is
             ,
             because
             it
             is
             in
             equilibrio
             with
             other
             six
             .
             'T
             is
             just
             so
             here
             ,
             I
             must
             find
             the
             weight
             of
             the
             Air
             L
             M
             ,
             while
             I
             poise
             the
             Tub
             ,
             because
             it
             wants
             a
             weight
             to
             counterballance
             it
             .
             I
             prove
             the
             
               minor
               proposition
            
             thus
             .
             If
             any
             thing
             counterballance
             the
             Air
             L
             M
             ,
             it
             must
             either
             be
             the
             Air
             below
             ,
             namely
             the
             part
             E
             ;
             or
             the
             Water
             E
             G
             :
             but
             neither
             of
             the
             twain
             can
             do
             it
             .
             Not
             the
             Air
             E
             ,
             because
             it
             hath
             as
             great
             a
             burden
             upon
             it
             ,
             as
             it
             is
             able
             to
             support
             ,
             namely
             the
             Water
             E
             G
             ,
             that
             weighs
             1904
             pound
             .
             And
             for
             this
             cause
             ,
             not
             the
             VVater
             it self
             ,
             seing
             all
             the
             force
             it
             can
             have
             to
             counterballance
             L
             M
             ,
             is
             from
             the
             surface
             of
             Air
             E
             ;
             but
             this
             is
             in
             equilibrio
             with
             it
             already
             .
             I
             said
             that
             the
             Air
             L
             M
             ,
             was
             exactly
             1904
             pound
             weight
             .
             This
             also
             is
             evident
             ,
             because
             it
             is
             just
             of
             these
             same
             dimensions
             ,
             with
             the
             Air
             F
             H.
             If
             it
             be
             said
             ,
             the
             Air
             L
             M
             must
             be
             thicker
             ;
             seing
             it's
             equal
             to
             the
             Tub
             without
             ;
             but
             the
             Air
             
             F
             H
             ,
             is
             only
             equal
             to
             the
             Tub
             within
             .
             I
             answer
             ,
             it
             is
             so
             indeed
             ;
             but
             here
             is
             a
             solution
             to
             the
             difficulty
             .
             I
             do
             not
             find
             the
             whole
             weight
             of
             the
             Air
             L
             M
             ,
             but
             only
             as
             much
             of
             it
             ,
             as
             is
             equal
             to
             F
             H.
             Suppose
             the
             Tub
             to
             be
             12
             inches
             within
             ,
             from
             side
             to
             side
             ,
             and
             16
             without
             ,
             from
             side
             to
             side
             .
             I
             say
             then
             ,
             I
             find
             only
             the
             burden
             of
             so
             much
             Air
             ,
             as
             answers
             to
             the
             cavity
             of
             the
             Tub
             ,
             because
             the
             rest
             of
             these
             inches
             ,
             are
             counterpoised
             ,
             by
             as
             much
             below
             ,
             namely
             by
             the
             Air
             ,
             that
             environs
             the
             orifice
             E
             :
             for
             it
             's
             supposed
             ,
             that
             if
             the
             Tub
             be
             two
             inches
             thick
             above
             ,
             it
             must
             be
             as
             thick
             in
             the
             lips
             .
             So
             that
             the
             whole
             Tub
             ,
             is
             not
             unequally
             prest
             ,
             but
             only
             so
             much
             of
             it
             within
             upon
             the
             top
             ,
             as
             answers
             to
             the
             cavity
             .
             Tenthly
             ,
             that
             when
             the
             Pipe
             is
             but
             half
             full
             of
             VVater
             ,
             namely
             from
             E
             to
             K
             ,
             I
             find
             only
             952
             pound
             of
             the
             Air
             L
             M
             ,
             though
             before
             I
             found
             1904.
             
             The
             reason
             is
             ,
             because
             the
             one
             half
             of
             it
             is
             now
             counterpoised
             by
             the
             Air
             I
             G
             ,
             and
             therefore
             the
             weight
             of
             it
             becomes
             insensible
             .
             'T
             is
             clear
             from
             the
             sixth
             assertion
             ,
             that
             the
             Air
             I
             G
             ,
             presseth
             down
             with
             952
             ;
             therefore
             it
             must
             press
             up
             with
             as
             much
             ,
             seing
             according
             to
             the
             sixth
             Theorem
             ,
             the
             Pressure
             of
             a
             Fluid
             is
             on
             every
             side
             .
             Eleventhly
             ,
             that
             when
             there
             is
             only
             eight
             foot
             of
             VVater
             and
             a
             half
             in
             the
             Tub
             ,
             namely
             between
             E
             and
             N
             ;
             I
             find
             only
             476
             pound
             of
             the
             Air
             L
             M.
             Because
             in
             this
             case
             ,
             the
             Air
             N
             G
             counterpoiseth
             1428
             pound
             of
             it
             .
             For
             if
             the
             said
             Air
             ,
             burden
             the
             Water
             N
             E
             ,
             with
             1428
             pound
             ,
             as
             is
             clear
             from
             the
             seventh
             assertion
             ,
             it
             must
             likewise
             press
             up
             the
             Tub
             with
             as
             much
             ,
             and
             so
             counterpoise
             as
             much
             of
             the
             Air
             L
             M.
             Twelfthly
             ,
             that
             when
             there
             is
             nothing
             within
             the
             Pipe
             but
             Air
             ,
             the
             whole
             weight
             of
             the
             Air
             L
             M
             becomes
             insensible
             to
             me
             .
             The
             reason
             is
             evident
             ,
             because
             it
             is
             wholly
             counterpoised
             by
             the
             Air
             within
             the
             Pipe.
             I
             affirm
             thirteenthly
             ,
             that
             
             the
             VVater
             E
             G
             ,
             is
             in
             equilibrio
             with
             the
             Water
             A
             B
             :
             that
             's
             to
             say
             1904
             pound
             ,
             is
             in
             equilibrio
             with
             476
             pound
             .
             I
             prove
             it
             evidently
             ,
             by
             the
             first
             medium
             ;
             all
             the
             parts
             of
             an
             Horizontal
             surface
             ,
             are
             equally
             prest
             ;
             therefore
             the
             part
             A
             ,
             sustains
             no
             more
             burden
             ,
             then
             the
             part
             E
             ,
             therefore
             A
             B
             ,
             is
             as
             heavy
             as
             E
             G
             ,
             and
             consequently
             ,
             the
             Air
             C
             D
             ,
             must
             be
             as
             heavy
             ,
             as
             the
             Air
             F
             H.
             Lest
             this
             proposition
             may
             seem
             to
             contradict
             what
             is
             already
             said
             ,
             I
             must
             distinguish
             a
             twofold
             Ballance
             ,
             according
             to
             the
             third
             Theorem
             ,
             one
             Natural
             ,
             another
             Artificial
             .
             In
             the
             
               Artificial
               Ballance
            
             ,
             where
             magnitudes
             do
             weigh
             according
             to
             all
             their
             dimensions
             ,
             
               viz.
               Longitude
               ,
               Latitude
            
             ,
             and
             Profundity
             ,
             the
             Water
             A
             B
             ,
             and
             the
             Water
             E
             G
             ,
             are
             not
             in
             equilibrio
             together
             ,
             seing
             the
             one
             is
             1428
             pound
             heavier
             than
             the
             other
             .
             But
             in
             the
             Ballance
             of
             Nature
             ,
             such
             as
             these
             Pipes
             are
             ,
             all
             the
             four
             makes
             an
             equipondium
             together
             ;
             because
             they
             do
             not
             weigh
             here
             ,
             according
             to
             their
             thickness
             ,
             but
             only
             according
             to
             their
             altitude
             .
             Therefore
             seing
             A
             B
             is
             as
             high
             as
             E
             G
             ,
             and
             seing
             C
             D
             is
             as
             high
             as
             F
             H
             ,
             they
             must
             all
             be
             of
             the
             same
             weight
             .
          
           
             From
             the
             first
             assertion
             I
             infer
             ,
             that
             one
             and
             the
             same
             Fluid
             ,
             even
             in
             the
             Ballance
             of
             Nature
             ,
             may
             sometimes
             be
             in
             equilibrio
             with
             a
             lesser
             weight
             ,
             and
             sometimes
             with
             a
             greater
             ,
             because
             the
             Air
             C
             D
             ,
             that
             weighs
             really
             476
             pound
             ,
             is
             in
             equilibrio
             with
             the
             Water
             A
             B
             ,
             that
             weighs
             but
             168.
             
             This
             is
             ,
             when
             A
             B
             is
             supposed
             to
             be
             only
             12
             foot
             high
             .
             It
             's
             likewise
             in
             equilibrio
             with
             it
             ,
             when
             it
             s
             34
             foot
             high
             .
             But
             how
             can
             A
             B
             ,
             that
             's
             12
             foot
             high
             ,
             press
             A
             ,
             with
             as
             much
             weight
             ,
             as
             when
             it
             s
             34
             foot
             high
             ?
             I
             answer
             by
             a
             similitude
             ,
             when
             a
             Cylinder
             of
             Wood
             12
             foot
             high
             stands
             upon
             a
             Table
             ,
             it
             may
             burden
             it
             as
             much
             ,
             as
             if
             it
             were
             a
             Cylinder
             34
             foot
             high
             .
             For
             ,
             supposing
             it
             to
             be
             
             thrust
             in
             ,
             between
             it
             ,
             and
             
               v.
               g.
            
             the
             ceiling
             of
             the
             room
             above
             ,
             it
             must
             press
             down
             with
             more
             weight
             ,
             then
             if
             it
             were
             not
             thrust
             in
             .
             So
             ,
             this
             Cylinder
             of
             Water
             A
             B
             ,
             that
             's
             but
             12
             foot
             high
             ,
             being
             prest
             between
             the
             surface
             A
             ,
             and
             the
             top
             of
             the
             Tub
             within
             ,
             must
             burden
             A
             ,
             as
             much
             ,
             as
             if
             it
             were
             34
             foot
             high
             ;
             for
             being
             of
             this
             hight
             ,
             it
             only
             stands
             upon
             the
             surface
             ,
             without
             pressing
             up
             the
             top
             of
             the
             Tub.
             
          
           
             I
             infer
             from
             the
             second
             assertion
             ,
             that
             each
             Pillar
             in
             a
             Fluid
             hath
             a
             determinate
             weight
             .
             This
             is
             evident
             from
             the
             determinate
             weight
             of
             A
             B
             ,
             that
             weighs
             first
             168
             pound
             ,
             being
             12
             foot
             high
             ,
             and
             467
             pound
             ,
             being
             34
             foot
             high
             ,
             and
             so
             of
             the
             rest
             .
             I
             infer
             secondly
             ,
             that
             the
             thicker
             ,
             and
             grosser
             a
             Pillar
             of
             a
             Fluid
             be
             ,
             it
             is
             the
             heavier
             ,
             (
             even
             in
             the
             
               Artificial
               Ballance
            
             )
             and
             contrariwise
             ,
             the
             more
             slender
             and
             thinner
             it
             be
             ,
             it
             is
             the
             lighter
             .
             This
             is
             evident
             from
             the
             Water
             A
             B
             ,
             six
             inches
             thick
             ,
             that
             weighs
             476
             pound
             ,
             and
             from
             the
             Water
             E
             G
             ,
             12
             inches
             thick
             ,
             that
             weighs
             1904
             pound
             .
             So
             doth
             the
             Pillar
             of
             Air
             C
             D
             ,
             weigh
             less
             ,
             then
             the
             Pillar
             F
             H.
             Here
             is
             ground
             for
             knowing
             the
             certain
             and
             determinate
             weight
             of
             a
             Pillar
             ,
             in
             any
             sort
             of
             a
             Fluid
             whatsoever
             .
             As
             to
             Air
             ,
             its
             clear
             and
             evident
             ,
             that
             a
             four-square
             Pillar
             thereof
             ,
             12
             inches
             every
             way
             ,
             weighs
             1904.
             
             That
             's
             to
             say
             ,
             if
             it
             were
             possible
             ,
             to
             take
             the
             Pillar
             of
             Air
             F
             H
             ,
             in
             its
             whole
             length
             ,
             from
             the
             surface
             of
             the
             earth
             ,
             to
             the
             top
             of
             the
             Atmosphere
             ,
             and
             pour
             it
             into
             the
             Scale
             of
             a
             Ballance
             ,
             it
             would
             be
             exactly
             the
             weight
             of
             1904
             pound
             .
             Here
             is
             a
             secret
             :
             though
             that
             same
             Pillar
             of
             Air
             ,
             were
             no
             longer
             ,
             than
             6
             or
             10
             foot
             ,
             yet
             the
             Pressure
             of
             it
             ,
             upon
             the
             body
             ,
             it
             rests
             upon
             ,
             is
             equivalent
             to
             1904
             pound
             .
             If
             this
             be
             ,
             (
             you
             say
             )
             what
             is
             the
             weight
             of
             Air
             ,
             that
             rests
             upon
             this
             Table
             ,
             that
             's
             36
             inches
             
             square
             ?
             I
             answer
             ,
             it
             must
             be
             as
             heavy
             ,
             as
             a
             Pillar
             of
             Water
             34
             foot
             high
             ,
             and
             36
             inches
             thick
             ,
             which
             will
             ,
             by
             just
             reckoning
             ,
             amount
             to
             17136
             pound
             ,
             or
             to
             1071
             stone
             weight
             .
             It
             may
             be
             inquired
             next
             ,
             what
             's
             the
             weight
             of
             the
             Air
             ,
             that
             burdens
             the
             pavement
             of
             this
             parlour
             ,
             that
             's
             16
             foot
             square
             ?
             I
             answer
             487424
             pound
             .
             Because
             it
             is
             exactly
             the
             weight
             of
             a
             bulk
             of
             Water
             34
             foot
             high
             ,
             and
             16
             foot
             thick
             .
             'T
             is
             to
             be
             remembred
             ,
             that
             though
             the
             Pressure
             of
             it
             ,
             be
             so
             much
             ,
             yet
             being
             poured
             into
             the
             scale
             of
             a
             Ballance
             ,
             it
             will
             not
             weigh
             so
             much
             :
             for
             not
             only
             as
             much
             as
             fills
             the
             room
             must
             be
             taken
             ,
             but
             as
             much
             as
             passeth
             from
             the
             pavement
             to
             the
             top
             of
             the
             Atmosphere
             .
             According
             to
             this
             method
             't
             is
             easie
             to
             determine
             the
             weight
             of
             any
             Pillar
             of
             Air
             whatsoever
             ,
             provided
             a
             man
             but
             once
             know
             the
             thickness
             of
             it
             ,
             both
             the
             wayes
             ,
             
               e.
               g.
            
             there
             's
             a
             planum
             12
             inches
             long
             ,
             and
             six
             inches
             broad
             ,
             upon
             which
             rests
             a
             Pillar
             of
             Air.
             The
             weight
             of
             it
             then
             is
             ,
             just
             the
             burden
             of
             a
             magnitude
             of
             Water
             34
             foot
             in
             hight
             ,
             12
             inches
             in
             length
             ,
             and
             six
             inches
             in
             breadth
             .
          
           
             Though
             the
             weight
             of
             any
             Pillar
             of
             Air
             may
             be
             known
             ,
             by
             knowing
             only
             the
             dimensions
             of
             it
             ,
             in
             breadth
             and
             length
             ;
             yet
             the
             weight
             of
             a
             Pillar
             of
             Water
             cannot
             be
             known
             ,
             unless
             all
             the
             three
             common
             dimensions
             of
             it
             ,
             be
             first
             known
             .
             The
             reason
             is
             this
             ,
             the
             Pillars
             of
             Air
             ,
             are
             all
             of
             the
             same
             hight
             ,
             but
             the
             Pillars
             of
             Water
             in
             the
             Ocean
             ,
             are
             of
             different
             hights
             :
             therefore
             ,
             not
             only
             must
             they
             be
             known
             ,
             
               secundum
               longitudinem
               ,
               &
               latitudinem
            
             ,
             in
             length
             and
             breadth
             ,
             but
             
               secundum
               profunditatem
            
             ,
             that
             is
             ,
             according
             to
             deepness
             .
             'T
             is
             easie
             to
             know
             then
             ,
             what
             each
             particular
             Pillar
             weighs
             .
             First
             then
             ,
             try
             how
             much
             weight
             is
             in
             a
             cubical
             foot
             of
             Water
             ,
             and
             having
             found
             this
             to
             be
             
               v.
               g.
            
             56
             pound
             ,
             you
             may
             determine
             ,
             that
             a
             
             Pillar
             of
             Water
             34
             foot
             high
             ,
             and
             12
             inches
             thick
             ,
             weighs
             1904
             pound
             .
             A
             Pillar
             34
             foot
             high
             ,
             and
             six
             inches
             thick
             weighs
             476
             pound
             .
             Note
             ,
             that
             in
             a
             Cube
             of
             Water
             six
             inches
             thick
             ,
             there
             are
             216
             inches
             ,
             which
             weighs
             seven
             pound
             .
             In
             a
             Pillar
             12
             inches
             thick
             ,
             and
             20
             fathom
             ,
             or
             100
             foot
             high
             ,
             you
             will
             find
             5600
             pound
             weight
             .
             In
             one
             ,
             of
             the
             same
             thickness
             ,
             but
             200
             fathom
             high
             ,
             there
             are
             56000
             ,
             fifty
             six
             thousand
             pound
             weight
             .
             In
             a
             Pillar
             three
             foot
             square
             ,
             and
             20
             fathom
             deep
             ,
             there
             are
             50400
             ,
             fifty
             thousand
             ,
             and
             four
             hundred
             pound
             weight
             .
             Make
             it
             800
             fathom
             high
             with
             that
             thickness
             ,
             and
             it
             will
             weigh
             504000
             ,
             five
             hundred
             and
             four
             thousand
             pound
             .
             But
             ,
             if
             according
             to
             the
             Theorem
             25
             ,
             you
             consider
             the
             weight
             of
             the
             Air
             above
             ,
             it
             will
             weigh
             521136
             ,
             five
             hundred
             ,
             twenty
             and
             one
             thousand
             ,
             one
             hundred
             thirty
             and
             six
             pound
             .
             A
             Pillar
             12
             foot
             square
             ,
             and
             300
             fathom
             deep
             ,
             weighs
             12096000
             ,
             twelve
             million
             ,
             ninety
             and
             six
             thousand
             pound
             ,
             Lastly
             suppose
             there
             were
             a
             bulk
             of
             Water
             500
             fathom
             deep
             ,
             and
             500
             fathom
             thick
             ,
             such
             a
             magnitude
             would
             weigh
             8750000000
             ,
             eight
             thousand
             seven
             hundred
             ,
             and
             fifty
             million
             of
             pounds
             .
             But
             if
             the
             Pressure
             of
             the
             Air
             ,
             that
             rests
             upon
             a
             surface
             of
             Water
             500
             fathom
             in
             breadth
             and
             length
             ,
             be
             taken
             in
             ,
             that
             weighs
             119000000
             ,
             a
             hundred
             and
             nineteen
             million
             of
             pounds
             ,
             the
             total
             ,
             that
             the
             bottom
             of
             the
             sea
             sustains
             ,
             must
             be
             8940000000
             ,
             eight
             thousand
             ,
             nine
             hundred
             and
             fourty
             million
             of
             pounds
             ,
             or
             558750000
             five
             hundred
             fifty
             and
             eight
             million
             ,
             seven
             hundred
             ,
             and
             fifty
             thousand
             stone
             weight
             .
          
           
             I
             infer
             from
             the
             fifth
             assertion
             ,
             that
             the
             lightest
             of
             Fluids
             may
             be
             brought
             to
             an
             equilibrium
             with
             the
             heaviest
             .
             For
             though
             Mercury
             be
             14000
             times
             heavier
             than
             Air
             ,
             
             yet
             the
             part
             of
             the
             surface
             A
             ,
             is
             no
             more
             prest
             with
             the
             Mercury
             A
             B
             ,
             then
             the
             part
             C
             is
             prest
             with
             the
             Air
             C
             D.
             Secondly
             ,
             that
             29
             inches
             of
             Mercury
             ,
             are
             of
             the
             same
             weight
             with
             34
             foot
             of
             Water
             .
             Thirdly
             ,
             the
             heavier
             a
             Fluid
             be
             naturally
             ,
             it
             hath
             the
             less
             altitude
             in
             the
             
               Natural
               Ballance
            
             ;
             and
             contrariwise
             ,
             the
             lighter
             it
             be
             ,
             it
             hath
             the
             more
             altitude
             .
             This
             is
             clear
             from
             the
             Mercury
             ,
             that
             's
             29
             inches
             ,
             the
             Water
             that
             's
             34
             foot
             ,
             and
             the
             Air
             ,
             that
             's
             counted
             6867
             fathom
             .
          
           
             I
             infer
             from
             the
             sixth
             assertion
             ,
             that
             two
             Fluids
             of
             different
             gravities
             ,
             may
             make
             an
             equilibrium
             with
             a
             third
             of
             the
             same
             kind
             .
             Because
             the
             27
             foot
             of
             Air
             I
             G
             ,
             and
             the
             17
             foot
             of
             Water
             E
             K
             ,
             are
             in
             equilibrio
             with
             the
             Air
             F
             H.
             I
             infer
             secondly
             ,
             that
             17
             foot
             of
             Air
             ,
             may
             be
             as
             heavy
             as
             17
             foot
             of
             Water
             ,
             because
             the
             Air
             I
             G
             ,
             is
             exactly
             as
             heavy
             ,
             as
             the
             Water
             E
             K.
             I
             infer
             thirdly
             ,
             that
             the
             Bensil
             of
             a
             Fluid
             ,
             is
             a
             thing
             really
             distinct
             ,
             from
             the
             
               Natural
               weight
            
             of
             it
             :
             because
             the
             Pressure
             of
             the
             Air
             I
             G
             ,
             is
             952
             pound
             ;
             but
             the
             natural
             weight
             of
             it
             will
             not
             exceed
             ,
             if
             it
             were
             weighed
             in
             a
             Ballance
             ,
             two
             or
             three
             ounces
             .
             I
             infer
             fourthly
             ,
             that
             Air
             cannot
             suffer
             dilatation
             ,
             but
             it
             must
             lose
             of
             it's
             Pressure
             .
             Because
             the
             Air
             I
             G
             ,
             that
             ought
             to
             weigh
             1904
             pound
             ,
             weighs
             only
             952.
             
             For
             understanding
             this
             ,
             you
             must
             know
             ,
             that
             when
             a
             Pipe
             is
             about
             half
             full
             of
             Air
             ,
             and
             half
             full
             of
             Water
             ,
             and
             inverted
             ,
             so
             much
             of
             the
             Water
             falls
             out
             ,
             and
             consequently
             so
             many
             inches
             doth
             the
             Air
             above
             it
             ,
             expand
             it self
             .
             So
             to
             make
             this
             Pipe
             that
             's
             34
             foot
             high
             ,
             half
             full
             of
             Air
             and
             half
             full
             of
             Water
             ,
             you
             must
             pour
             in
             about
             19
             foot
             of
             Water
             ,
             and
             the
             15
             foot
             of
             Air
             that
             's
             in
             it
             besides
             ,
             will
             ,
             when
             the
             Pipe
             is
             inverted
             ,
             go
             up
             and
             expand
             it self
             to
             17
             foot
             ,
             two
             foot
             of
             Water
             falling
             out
             .
          
           
           
             I
             infer
             from
             the
             seventh
             assertion
             ,
             that
             when
             there
             are
             two
             Fluids
             of
             different
             gravities
             ,
             and
             weights
             counterpoising
             a
             third
             ,
             by
             what
             proportion
             the
             one
             grows
             lighter
             ,
             by
             that
             same
             proportion
             the
             other
             becomes
             heavier
             .
             For
             ,
             when
             the
             VVater
             E
             K
             ,
             that
             weighs
             952
             pound
             ,
             becomes
             E
             N
             ,
             that
             weighs
             476
             ,
             the
             Air
             above
             it
             ,
             that
             weighed
             952
             ,
             becomes
             now
             1428
             pound
             .
          
           
             I
             infer
             from
             the
             eighth
             ,
             that
             the
             pondus
             of
             a
             Fluid
             ,
             cannot
             be
             counterpoised
             ,
             by
             two
             distinct
             powers
             .
             Because
             the
             34
             foot
             of
             Water
             E
             G
             ,
             cannot
             be
             both
             sustained
             ,
             by
             the
             part
             of
             the
             surface
             of
             Air
             E
             ,
             and
             my
             hand
             .
             I
             infer
             from
             the
             ninth
             ,
             that
             the
             Pressure
             and
             weight
             of
             a
             Fluid
             ,
             may
             be
             found
             ,
             even
             in
             its
             own
             Element
             ,
             by
             sense
             .
             Because
             in
             poising
             of
             the
             Tub
             ,
             I
             find
             the
             weight
             of
             the
             Air
             L
             M.
             I
             infer
             secondly
             ,
             that
             the
             weight
             of
             a
             Fluid
             is
             only
             found
             in
             its
             own
             Element
             ,
             when
             there
             is
             not
             a
             potentia
             to
             counterpoise
             the
             pondus
             of
             it
             ,
             because
             I
             find
             only
             the
             weight
             of
             the
             Air
             L
             M
             ,
             because
             it
             wants
             a
             potentia
             to
             counterpoise
             it
             .
             I
             infer
             thirdly
             ,
             that
             it
             is
             very
             possible
             even
             in
             the
             
               Artificial
               Ballance
            
             ,
             to
             weigh
             a
             Fluid
             in
             its
             own
             Element
             ,
             and
             to
             know
             the
             precise
             weight
             of
             it
             ,
             to
             a
             grain
             .
             For
             this
             cause
             ,
             take
             a
             small
             chord
             ,
             and
             fasten
             therewith
             the
             top
             of
             the
             Pipe
             G
             ,
             to
             the
             Scale
             of
             a
             Ballance
             ,
             and
             the
             Lead
             or
             Stone
             that
             makes
             the
             counterpoise
             in
             the
             opposite
             Scale
             ,
             is
             the
             just
             weight
             of
             the
             Air
             L
             M.
             
          
           
           
           
             To
             put
             a
             close
             to
             this
             Experiment
             ,
             let
             us
             suppose
             the
             Pipe
             E
             G
             to
             be
             68
             foot
             high
             ,
             and
             void
             of
             Air.
             If
             then
             the
             orifice
             E
             be
             drowned
             among
             stagnant
             Water
             ,
             the
             Liquor
             of
             its
             own
             accord
             (
             as
             it
             were
             )
             will
             rise
             from
             E
             to
             K
             34
             foot
             ,
             the
             other
             half
             I
             G
             remaining
             empty
             .
             This
             evidently
             shews
             ,
             that
             the
             Pressure
             of
             the
             Air
             ,
             hath
             a
             
               Sphere
               of
               Activity
            
             ,
             beyond
             which
             it
             is
             not
             able
             to
             raise
             or
             press
             up
             a
             pillar
             of
             VVater
             .
             'T
             is
             folly
             then
             to
             think
             that
             Water
             may
             be
             conveyed
             over
             high
             places
             by
             the
             help
             of
             a
             
               Siphon
               ,
               v.
               g.
            
             from
             the
             one
             side
             of
             a
             Hill
             over
             the
             top
             ,
             to
             the
             other
             side
             .
             For
             ,
             if
             that
             hight
             exceed
             perpendicularly
             34
             foot
             ,
             no
             Art
             will
             do
             it
             .
             Yet
             contrariwise
             ,
             it
             is
             possible
             to
             transport
             Water
             ,
             by
             Pipes
             and
             Siphons
             ,
             not
             only
             34
             foot
             below
             the
             source
             ,
             but
             3400.
             
             Nay
             ,
             if
             there
             were
             a
             Siphon
             passing
             from
             the
             surface
             of
             the
             Earth
             to
             the
             Center
             ,
             and
             thence
             rising
             to
             the
             surface
             again
             ,
             it
             would
             convey
             Water
             from
             the
             one
             place
             to
             the
             other
             .
             For
             't
             is
             a
             certain
             and
             infallible
             rule
             in
             the
             Hydrostaticks
             ,
             that
             Water
             will
             rise
             as
             high
             in
             this
             place
             ,
             as
             the
             hight
             of
             the
             place
             is
             ,
             from
             whence
             it
             comes
             ,
             even
             though
             the
             windings
             and
             turnings
             of
             the
             Lead-Conduits
             under-ground
             were
             as
             a
             Labyrinth
             ,
             and
             though
             this
             place
             ,
             were
             not
             only
             1000
             ,
             but
             5000
             pace
             distant
             from
             the
             other
             .
             'T
             is
             to
             be
             observed
             ,
             that
             if
             the
             mouth
             of
             the
             Conduit
             
             here
             ,
             be
             exactly
             as
             high
             as
             the
             other
             end
             at
             the
             Fountain
             ,
             the
             Water
             stands
             still
             .
             And
             the
             greater
             the
             difference
             be
             ,
             the
             Water
             flows
             out
             with
             the
             greater
             force
             .
             By
             the
             help
             of
             such
             Conduits
             ,
             't
             is
             easie
             to
             convey
             Water
             to
             a
             City
             many
             miles
             .
             Such
             Pipes
             are
             ordinarily
             made
             of
             Lead
             .
             But
             for
             saving
             expence
             ,
             they
             may
             be
             made
             of
             Timber
             ,
             or
             Clay
             well
             burnt
             in
             an
             Oven
             .
          
        
      
       
         
         
           AN
           ACCOMPT
           OF
           Miscellany
           OBSERVATIONS
           ,
           Lately
           made
           ,
           by
           the
           Author
           of
           the
           foregoing
           EXPERIMENTS
           .
        
         
           
             OBSERVATION
             I.
             
          
           
             IN
             May
             1669
             ,
             there
             was
             need
             of
             a
             new
             Sink
             ,
             on
             the
             east
             side
             of
             Tranent
             ,
             for
             winning
             of
             Coals
             .
             But
             while
             the
             Coal-hewers
             were
             in
             digging
             down
             ,
             and
             had
             come
             the
             deepness
             of
             13
             or
             14
             fathom
             ,
             they
             were
             stopped
             from
             working
             by
             Damps
             ,
             or
             ill
             Air
             ,
             that
             flowed
             out
             plentifully
             from
             the
             sides
             of
             the
             sink
             ,
             wherein
             there
             were
             a
             great
             number
             of
             Cutters
             ,
             or
             rifts
             ,
             out
             of
             which
             that
             ill
             Air
             came
             .
             To
             try
             the
             nature
             and
             power
             of
             Damps
             ,
             I
             took
             a
             dog
             ,
             and
             fastned
             him
             in
             a
             bucket
             ,
             with
             a
             small
             roap
             ,
             that
             he
             might
             not
             leap
             over
             ,
             and
             when
             he
             had
             gone
             down
             7
             or
             8
             fathom
             ,
             he
             presently
             begins
             to
             howl
             ,
             and
             cry
             pitifully
             ,
             as
             if
             he
             had
             been
             
             beaten
             sore
             with
             a
             rod
             ,
             and
             a
             little
             after
             ,
             he
             begins
             to
             stagger
             ,
             and
             his
             feet
             failing
             him
             ,
             he
             falls
             down
             ,
             as
             one
             overtaken
             with
             the
             Epilepsy
             ,
             and
             in
             going
             down
             to
             the
             bottom
             ,
             his
             eyes
             turning
             in
             his
             head
             ,
             they
             appeared
             very
             shining
             and
             clear
             like
             two
             large
             bright
             Diamonds
             .
             Fearing
             ,
             that
             the
             Damp
             should
             have
             killed
             him
             out
             of
             hand
             ,
             he
             was
             instantly
             pulled
             up
             from
             the
             bottom
             ,
             where
             he
             had
             not
             tarried
             15
             seconds
             of
             time
             .
             And
             when
             the
             bucket
             had
             come
             to
             the
             mouth
             of
             the
             sink
             ,
             he
             was
             pulled
             out
             ,
             and
             laid
             upon
             the
             ground
             ,
             to
             get
             fresh
             Air.
             When
             he
             had
             lien
             a
             while
             as
             dead
             ,
             he
             begins
             at
             last
             to
             gape
             ,
             and
             gasp
             ,
             and
             makesome
             respirations
             ,
             as
             if
             he
             had
             been
             rather
             expiring
             ,
             than
             recovering
             .
             Next
             ,
             he
             began
             to
             stir
             and
             move
             his
             feet
             ,
             and
             after
             ,
             to
             raise
             himself
             upon
             his
             knees
             ,
             his
             head
             staggering
             and
             wavering
             from
             side
             to
             side
             .
             After
             a
             minut
             or
             two
             ,
             he
             was
             able
             to
             stand
             upon
             his
             feet
             ,
             but
             so
             weakly
             ,
             that
             he
             was
             not
             in
             capacity
             to
             walk
             or
             run
             .
             Yet
             at
             last
             ,
             being
             much
             refreshed
             ,
             he
             escaped
             from
             us
             ,
             and
             ran
             home
             ,
             but
             slowly
             .
             In
             the
             afternoon
             ,
             the
             same
             Experiment
             was
             repeated
             ,
             with
             another
             dog
             ,
             whose
             case
             was
             the
             same
             in
             all
             things
             .
             But
             after
             he
             was
             perfectly
             recovered
             ,
             for
             a
             further
             trial
             ,
             we
             let
             him
             down
             the
             second
             time
             ,
             and
             suffered
             him
             to
             tarry
             in
             the
             bottom
             of
             the
             sink
             ,
             about
             the
             space
             of
             three
             minuts
             :
             but
             when
             he
             was
             pulled
             up
             ,
             and
             taken
             out
             ,
             we
             found
             no
             symptomes
             of
             life
             in
             him
             ;
             and
             so
             after
             half
             an
             hour
             and
             more
             ,
             his
             body
             began
             to
             swell
             ,
             which
             ordinarily
             befalls
             such
             ,
             who
             are
             killed
             after
             this
             manner
             .
             After
             this
             ,
             we
             sent
             down
             in
             the
             Bucket
             ,
             a
             little
             Chicken
             ,
             which
             ,
             when
             it
             came
             near
             the
             Damp
             ,
             presently
             flapped
             with
             the
             wings
             ,
             and
             falling
             down
             ,
             turned
             over
             and
             over
             for
             a
             pretty
             while
             ,
             as
             if
             it
             had
             been
             taken
             with
             a
             vertigo
             ,
             or
             giddiness
             .
             But
             by
             drawing
             up
             the
             Bucket
             in
             haste
             ,
             and
             bringing
             the
             Bird
             to
             the
             fresh
             Air
             ,
             it
             recovered
             .
             In
             the
             
             evening
             ,
             we
             let
             down
             a
             
               lighted
               Candle
            
             ,
             but
             it
             was
             soon
             extinguished
             ,
             when
             it
             came
             near
             mid-sink
             ;
             for
             here
             ,
             rather
             than
             in
             the
             bottom
             ,
             was
             the
             strongest
             Damp.
             Lastly
             ,
             we
             let
             down
             by
             a
             chord
             ,
             a
             Brand-iron
             ,
             with
             burning
             Coals
             ,
             whose
             flame
             was
             soon
             put
             out
             ,
             and
             after
             a
             little
             while
             ,
             we
             perceived
             the
             red
             Coals
             to
             be
             extinguished
             by
             degrees
             ;
             yet
             not
             totally
             ,
             because
             ,
             as
             the
             Coal-hewers
             observed
             ,
             the
             power
             of
             the
             Damp
             was
             not
             so
             strong
             ,
             as
             before
             .
             These
             Damps
             then
             have
             their
             ebbings
             and
             flowings
             ,
             which
             seem
             to
             depend
             upon
             the
             weather
             ,
             or
             rather
             upon
             the
             situation
             of
             the
             winds
             ,
             and
             their
             force
             .
             For
             't
             is
             observed
             ,
             that
             a
             high
             South-west
             wind
             causeth
             ill
             Air
             in
             this
             place
             ;
             and
             that
             ,
             by
             reason
             of
             much
             wast
             ground
             ,
             that
             lies
             upon
             the
             South
             ,
             and
             South-west
             hand
             of
             this
             Sink
             ,
             whence
             are
             conveyed
             under
             ground
             by
             secret
             passages
             ,
             which
             are
             nothing
             else
             but
             so
             many
             rifts
             and
             openings
             ,
             commonly
             called
             by
             the
             
               Coal-hewers
               ,
               Cutters
            
             ,
             corrupted
             and
             rotten
             Air
             ,
             full
             of
             sulphurious
             stems
             .
             The
             reason
             why
             these
             passages
             are
             open
             ,
             and
             replenished
             with
             nothing
             ,
             but
             corrupted
             Air
             ,
             is
             this
             ,
             the
             Water
             ,
             that
             's
             ordinarily
             called
             the
             Blood
             of
             the
             Coal
             ,
             being
             withdrawn
             with
             subterraneous
             Gutters
             (
             commonly
             called
             Levels
             )
             that
             are
             digged
             ,
             and
             wrought
             under
             ground
             ,
             sometimes
             a
             very
             long
             way
             ,
             for
             drying
             of
             the
             Mines
             ,
             and
             the
             veins
             of
             the
             earth
             being
             now
             empty
             ,
             there
             succeeds
             Air
             ;
             which
             Air
             ,
             by
             process
             of
             time
             ,
             and
             long
             standing
             ,
             rots
             ,
             and
             contracts
             a
             sulphurious
             quality
             ,
             which
             causeth
             sudden
             death
             .
             Now
             ,
             when
             the
             wind
             is
             high
             ,
             and
             strong
             from
             the
             South
             or
             South-west
             ,
             that
             sulphurious
             Air
             is
             driven
             through
             the
             ground
             ,
             and
             coming
             to
             Sinks
             and
             Mines
             ,
             where
             men
             are
             working
             ,
             presently
             infects
             the
             place
             ,
             and
             hinders
             the
             work
             .
             'T
             is
             often
             observed
             ,
             that
             the
             wind
             and
             Air
             under
             ground
             ,
             keep
             a
             correspondence
             in
             their
             motion
             ,
             
             with
             the
             wind
             above
             ground
             :
             and
             therefore
             ,
             when
             the
             wind
             is
             in
             such
             a
             point
             above
             ,
             't
             is
             found
             ,
             that
             the
             motion
             of
             the
             Air
             below
             runs
             such
             a
             way
             ,
             and
             the
             contrary
             way
             ,
             when
             the
             wind
             above
             ground
             ,
             is
             in
             the
             opposite
             point
             .
             When
             there
             is
             a
             free
             passage
             between
             the
             bottom
             of
             the
             two
             Sinks
             ,
             you
             may
             observe
             the
             wind
             come
             down
             through
             the
             one
             ,
             and
             running
             alongst
             under
             the
             ground
             ,
             rise
             up
             thorow
             the
             other
             ,
             even
             as
             Water
             runs
             thorow
             a
             Siphon
             .
             For
             this
             cause
             ,
             when
             the
             Coal-hewers
             have
             done
             with
             such
             a
             Sink
             ,
             they
             do
             not
             use
             to
             stop
             it
             ,
             or
             close
             it
             up
             ,
             but
             leaves
             it
             standing
             open
             ,
             that
             the
             Air
             under
             ground
             may
             be
             kept
             under
             a
             perpetual
             motion
             and
             stirring
             ,
             which
             to
             them
             is
             a
             great
             advantage
             .
             'T
             is
             very
             strange
             to
             see
             sometimes
             ,
             how
             much
             Air
             ,
             and
             how
             fresh
             it
             will
             be
             ,
             even
             at
             a
             very
             great
             distance
             ,
             namely
             four
             or
             five
             hundred
             pace
             ,
             from
             the
             mouth
             of
             the
             Sink
             .
             This
             could
             never
             be
             ,
             unless
             there
             were
             a
             considerable
             Pressure
             and
             weight
             in
             it
             ,
             whereby
             it
             is
             driven
             forward
             ,
             thorow
             so
             many
             Labyrinths
             .
             And
             even
             in
             the
             utmost
             room
             ,
             where
             the
             Coal-hewers
             are
             working
             ,
             the
             Pressure
             is
             as
             great
             ,
             as
             it
             is
             above
             ground
             ,
             which
             is
             found
             by
             the
             
               Torricellian
               Experiment
            
             .
             In
             such
             a
             case
             ,
             the
             Air
             cannot
             press
             down
             thorow
             the
             Earth
             and
             Metalls
             ,
             therefore
             the
             Mercury
             must
             be
             suspended
             ,
             not
             by
             a
             Pillar
             from
             the
             Atmosphere
             ,
             but
             by
             the
             Bensil
             of
             it
             .
             Nay
             ,
             put
             the
             case
             ,
             that
             the
             whole
             Element
             of
             Air
             were
             destroyed
             ,
             and
             this
             remaining
             ,
             yet
             would
             it
             be
             able
             to
             support
             29
             inches
             .
             To
             shut
             up
             this
             discourse
             ,
             it
             is
             observed
             by
             the
             Coal-hewers
             ,
             that
             when
             there
             is
             ill
             Air
             in
             a
             Sink
             ,
             a
             man
             may
             perceive
             distinctly
             ,
             what
             is
             lying
             in
             the
             bottom
             ,
             so
             clear
             and
             transparent
             is
             the
             Air
             of
             it
             :
             but
             when
             the
             Damp
             is
             gone
             ,
             the
             Medium
             is
             not
             so
             clear
             .
             In
             temperat
             and
             cold
             weather
             ,
             the
             Damps
             are
             not
             so
             frequent
             .
             From
             this
             Sink
             ,
             in
             soft
             winds
             ,
             or
             in
             Northerly
             winds
             ,
             or
             when
             it
             blows
             from
             East
             or
             North-east
             ,
             the
             Damps
             are
             driven
             away
             .
          
        
         
           
           
             OBSERVATION
             II.
             
          
           
             JUpiter
             upon
             Wednesday
             night
             ,
             at
             eleven
             a
             clock
             ,
             being
             24
             of
             November
             ,
             1669
             ,
             had
             the
             following
             position
             with
             the
             stars
             of
             Gemini
             .
             He
             was
             so
             near
             to
             the
             Star
             C
             ,
             that
             to
             appearance
             ,
             the
             points
             of
             his
             rayes
             did
             touch
             it
             .
             This
             Star
             by
             looking
             upon
             the
             material
             Glob
             ,
             is
             fixed
             in
             the
             very
             Zodiack
             ,
             and
             in
             the
             13
             degree
             of
             Cancer
             ,
             and
             is
             the
             very
             navel
             of
             the
             following
             Twine
             .
             The
             Star
             A
             is
             Castor
             .
             The
             Star
             B
             is
             Pollux
             .
             The
             star
             D
             ,
             is
             fixed
             in
             the
             forefoot
             of
             the
             following
             Twine
             .
             From
             this
             place
             he
             moved
             ,
             with
             a
             retrograde
             motion
             ,
             till
             he
             came
             to
             the
             5
             of
             Cancer
             ,
             about
             the
             20
             of
             February
             ,
             1670
             ,
             and
             from
             that
             time
             became
             Direct
             in
             his
             motion
             ,
             and
             so
             upon
             the
             27
             of
             March
             ,
             1670
             at
             9
             a
             clock
             ,
             he
             was
             in
             a
             right
             line
             with
             
               Canis
               minor
            
             ,
             and
             the
             brightest
             Star
             in
             Auriga
             ,
             and
             was
             in
             a
             right
             line
             with
             the
             eastmost
             shoulder
             of
             Orion
             ,
             and
             Castor
             in
             Gemini
             ,
             or
             with
             that
             Star
             ,
             when
             South-west
             ,
             that
             's
             highest
             ,
             and
             West-most
             .
          
        
         
           
             OBSERVATION
             III.
             
          
           
             IT
             is
             written
             in
             the
             History
             of
             the
             
               Royal
               Society
            
             ,
             that
             such
             a
             member
             of
             it
             ,
             whose
             name
             I
             have
             forgotten
             ,
             hath
             found
             out
             ,
             among
             many
             other
             curious
             inventions
             ,
             this
             ,
             namely
             a
             way
             for
             knowing
             the
             motion
             of
             the
             Sun
             in
             seconds
             of
             time
             :
             but
             is
             not
             pleased
             to
             reveal
             the
             manner
             how
             .
             Because
             such
             a
             device
             may
             be
             usefull
             in
             Astronomy
             ,
             and
             likewise
             for
             adjusting
             the
             
               Pendulum
               Clock
            
             ,
             I
             shall
             therefore
             briefly
             shew
             ,
             the
             manner
             and
             way
             how
             such
             a
             thing
             may
             be
             done
             ,
             as
             I
             have
             tried
             it
             my self
             .
             I
             took
             an
             
               Optick
               Tub
            
             ,
             about
             12
             foot
             long
             ,
             only
             with
             two
             Convex-glasses
             
             in
             it
             ,
             and
             did
             so
             place
             it
             in
             a
             dark
             room
             ,
             by
             putting
             the
             one
             end
             ,
             in
             which
             was
             the
             Object-glass
             ,
             without
             the
             window
             ,
             and
             keeping
             the
             other
             within
             ,
             that
             I
             caused
             the
             beams
             of
             the
             Sun
             shine
             thorow
             it
             ,
             which
             were
             received
             upon
             a
             white
             wall
             four
             or
             five
             foot
             from
             the
             Tub.
             This
             image
             ,
             which
             was
             perfectly
             round
             ,
             and
             splendid
             ,
             did
             move
             alongst
             the
             wall
             very
             quickly
             ,
             so
             that
             in
             a
             minut
             of
             time
             ,
             it
             did
             advance
             seven
             inches
             and
             a
             half
             ,
             which
             will
             be
             the
             eight
             part
             of
             an
             inch
             in
             a
             second
             ,
             a
             motion
             very
             sensible
             .
             Now
             ,
             this
             beam
             that
             came
             thorow
             the
             Tub
             ,
             and
             lighted
             upon
             the
             wall
             ,
             would
             not
             have
             moved
             one
             inch
             in
             a
             minut
             ,
             if
             it
             had
             wanted
             the
             two
             Glasses
             ;
             for
             as
             they
             magnify
             ,
             and
             seem
             to
             bring
             nearer
             the
             Object
             ,
             so
             they
             quicken
             the
             motion
             of
             it
             .
             In
             a
             word
             ,
             by
             what
             proportion
             the
             Object
             is
             made
             more
             ,
             by
             that
             same
             proportion
             is
             the
             motion
             quickned
             .
             'T
             is
             to
             be
             observed
             ,
             that
             the
             longer
             the
             Tub
             be
             ,
             the
             motion
             is
             the
             swifter
             :
             for
             as
             the
             longest
             Tub
             doth
             ordinarily
             most
             magnify
             the
             object
             ;
             so
             doth
             it
             most
             quicken
             the
             motion
             .
             Next
             ,
             the
             farther
             distant
             the
             white
             wall
             is
             from
             the
             end
             of
             the
             Tub
             ,
             the
             larger
             is
             the
             image
             ;
             and
             contrariwise
             ,
             the
             nearer
             it
             be
             ,
             it
             is
             the
             less
             .
             Thirdly
             ,
             the
             farther
             the
             wall
             be
             from
             the
             end
             of
             the
             Tub
             ,
             the
             circumference
             of
             the
             image
             is
             the
             more
             confused
             ,
             and
             the
             nearer
             it
             be
             ,
             it
             is
             the
             more
             distinct
             .
             Fourthly
             ,
             the
             darker
             the
             room
             be
             ,
             it
             is
             so
             much
             the
             better
             .
             Lastly
             ,
             this
             trial
             may
             be
             made
             with
             ordinary
             Prospects
             ,
             of
             a
             foot
             ,
             two
             foot
             ,
             or
             three
             foot
             long
             ,
             which
             will
             really
             do
             the
             thing
             ,
             but
             not
             so
             sensibly
             ,
             unless
             the
             glasses
             be
             very
             good
             .
          
           
             As
             to
             the
             use
             of
             this
             device
             in
             Astronomy
             ,
             I
             shall
             not
             say
             much
             .
             But
             shall
             only
             mention
             what
             it
             may
             serve
             for
             in
             order
             to
             the
             Pendulum
             Clock
             .
             For
             this
             cause
             ,
             let
             a
             
             man
             choise
             a
             convenient
             room
             ,
             with
             a
             window
             to
             the
             South
             ,
             wherein
             this
             Tub
             may
             be
             so
             fixed
             ,
             that
             it
             may●ly
             just
             ,
             or
             very
             near
             to
             the
             true
             meridian
             ,
             and
             may
             move
             vertically
             upon
             an
             axil-tree
             ,
             because
             of
             the
             Suns
             declination
             every
             day
             .
             Then
             at
             a
             certain
             distance
             from
             the
             end
             of
             it
             ,
             fix
             and
             settle
             a
             large
             board
             of
             timber
             ,
             smooth
             ,
             and
             well
             plained
             ,
             and
             well
             whited
             ,
             for
             receiving
             the
             image
             .
             In
             the
             middle
             of
             this
             board
             ,
             draw
             a
             circle
             with
             Charcoal
             ,
             equal
             in
             diameter
             to
             the
             circle
             of
             the
             image
             .
             Now
             ,
             this
             being
             done
             ,
             you
             will
             find
             that
             assoon
             as
             the
             west
             side
             of
             the
             Sun
             ,
             begins
             to
             come
             near
             to
             the
             Meridian
             ,
             the
             image
             begins
             to
             appear
             upon
             the
             board
             ,
             like
             the
             segment
             of
             a
             circle
             ,
             and
             grows
             larger
             ,
             and
             larger
             ,
             till
             it
             become
             perfectly
             round
             .
             Now
             in
             the
             very
             instant
             of
             time
             ,
             wherein
             the
             image
             ,
             and
             the
             circle
             are
             united
             ,
             set
             the
             wheels
             of
             your
             Clock
             a
             going
             ,
             from
             the
             
               hour
               ,
               minut
            
             ,
             and
             second
             of
             XII
             .
             To
             morrow
             ,
             or
             3
             or
             4
             dayes
             after
             ,
             when
             you
             desire
             to
             make
             an
             examination
             ,
             wait
             on
             about
             12
             a
             clock
             ,
             when
             the
             Sun
             is
             coming
             to
             the
             Meridian
             ,
             and
             you
             will
             find
             what
             the
             difference
             is
             .
             If
             the
             Clock
             go
             slow
             ,
             observe
             ,
             assoon
             as
             the
             image
             is
             united
             with
             the
             circle
             (
             which
             you
             will
             perceive
             in
             a
             second
             of
             time
             )
             the
             variation
             ,
             that
             's
             to
             say
             ,
             how
             many
             seconds
             interveens
             between
             that
             second
             ,
             wherein
             the
             union
             fell
             ,
             and
             that
             second
             ,
             that
             closes
             XII
             hours
             in
             the
             Clock
             .
             If
             it
             go
             fast
             ,
             observe
             how
             many
             seconds
             passes
             from
             that
             second
             ,
             that
             ends
             XII
             hours
             ,
             and
             that
             wherein
             the
             image
             of
             the
             Sun
             is
             united
             with
             the
             circle
             ,
             which
             if
             you
             do
             ,
             you
             will
             know
             exactly
             ,
             what
             the
             difference
             is
             ,
             even
             to
             a
             second
             .
             But
             without
             this
             ,
             you
             will
             find
             great
             difficulty
             to
             know
             the
             variation
             in
             15
             or
             20
             seconds
             ,
             especially
             in
             a
             common
             Dial.
             But
             here
             ,
             you
             will
             see
             distinctly
             the
             image
             of
             the
             Sun
             move
             every
             second
             
             of
             time
             ,
             the
             eighth
             part
             ,
             or
             the
             sixth
             part
             ,
             or
             the
             fourth
             part
             of
             an
             inch
             ,
             according
             to
             the
             length
             of
             your
             Tub
             ,
             and
             goodness
             of
             your
             glasses
             .
             'T
             is
             to
             be
             observed
             ,
             that
             in
             adjusting
             the
             
               Pendulum
               Clock
            
             ,
             respect
             must
             be
             had
             to
             the
             table
             of
             Equation
             of
             dayes
             ,
             commonly
             known
             in
             Astronomy
             .
             For
             if
             this
             be
             not
             ,
             it
             is
             impossible
             to
             make
             it
             go
             right
             ,
             and
             that
             because
             all
             the
             natural
             dayes
             of
             the
             year
             ,
             are
             not
             equal
             among
             themselves
             :
             that
             's
             to
             say
             ,
             the
             time
             that
             's
             spent
             by
             the
             Suns
             motion
             from
             the
             Meridian
             this
             day
             ,
             to
             the
             same
             Meridian
             ,
             the
             next
             day
             ,
             is
             not
             equal
             ,
             but
             is
             more
             or
             less
             ,
             than
             the
             time
             spent
             betwixt
             Meridian
             and
             Meridian
             ,
             a
             third
             or
             fourth
             day
             after
             .
             For
             instance
             ,
             the
             Sun
             this
             day
             being
             11
             of
             Iuly
             ,
             comes
             sooner
             to
             the
             Meridian
             by
             three
             seconds
             of
             time
             ,
             than
             he
             came
             yesterday
             .
             Within
             9
             or
             10
             dayes
             ,
             (
             suppose
             the
             22
             of
             Iuly
             )
             he
             will
             be
             longer
             in
             coming
             to
             the
             Meridian
             by
             4
             seconds
             ,
             than
             upon
             the
             21.
             
             This
             difference
             I
             grant
             ,
             in
             short
             time
             is
             not
             sensible
             ,
             yet
             once
             in
             the
             year
             ,
             it
             will
             amount
             to
             more
             than
             half
             an
             hour
             .
             This
             inequality
             of
             dayes
             arises
             from
             two
             causes
             .
             First
             ,
             from
             the
             Suns
             eccentricity
             ,
             whereby
             he
             moves
             slowlier
             in
             one
             part
             of
             the
             Zodiack
             ,
             than
             in
             another
             :
             for
             in
             Summer
             when
             he
             is
             furthest
             from
             the
             Earth
             ,
             he
             goes
             slowlier
             back
             in
             the
             Ecliptick
             ,
             than
             in
             Winter
             ,
             when
             he
             is
             nearer
             to
             it
             .
             The
             second
             cause
             ,
             which
             is
             truly
             the
             far
             greater
             ,
             is
             this
             ,
             because
             in
             the
             diurnal
             motion
             of
             the
             Sun
             ,
             equal
             parts
             of
             the
             Aequator
             ,
             does
             not
             answer
             to
             equal
             parts
             of
             the
             Zodiack
             .
             Hence
             it
             followes
             ,
             that
             if
             the
             natural
             dayes
             be
             not
             equal
             among
             themselves
             ,
             the
             hours
             must
             be
             unequal
             also
             :
             but
             this
             is
             not
             considerable
             .
          
           
             By
             help
             of
             such
             a
             Tub
             placed
             in
             a
             dark
             room
             ,
             it
             is
             easie
             ,
             when
             the
             Sun
             is
             under
             Eclipse
             ,
             to
             enumerat
             distinctly
             
             the
             digits
             eclipsed
             .
             Likewise
             ,
             if
             you
             take
             out
             the
             object
             Glass
             ,
             and
             cover
             a
             hole
             in
             the
             window
             board
             with
             it
             ,
             you
             shall
             see
             distinctly
             upon
             a
             white
             wall
             ,
             the
             species
             and
             true
             representations
             of
             all
             objects
             without
             .
             And
             by
             comparing
             the
             quantity
             of
             the
             object
             without
             ,
             with
             the
             quantity
             of
             it
             within
             ,
             you
             may
             know
             the
             distance
             of
             it
             from
             the
             window
             ,
             though
             it
             were
             many
             miles
             .
             For
             as
             the
             one
             quantity
             ,
             is
             to
             the
             other
             ,
             so
             is
             the
             distance
             between
             the
             Glass
             and
             the
             object
             on
             the
             wall
             ,
             to
             the
             distance
             between
             the
             Glass
             and
             the
             object
             without
             .
          
           
             It
             may
             be
             inquired
             whether
             or
             not
             ,
             the
             retrograde
             ,
             as
             well
             as
             the
             
               diurnal
               motion
            
             of
             any
             of
             the
             Planets
             ,
             may
             be
             discerned
             ,
             in
             minuts
             or
             seconds
             ,
             by
             the
             help
             of
             a
             long
             Telescope
             ?
             In
             answer
             to
             this
             ,
             we
             must
             suppose
             the
             Planets
             only
             to
             have
             a
             retrograde
             motion
             ,
             and
             consequently
             to
             move
             slowly
             from
             West
             to
             East
             ,
             Saturn
             once
             in
             29
             years
             ,
             or
             30
             ,
             to
             run
             about
             the
             
               Zodiack
               ;
               Iupiter
            
             in
             12
             ,
             Mars
             in
             2
             years
             ,
             the
             Sun
             in
             one
             year
             ,
             Venus
             and
             Mercury
             in
             less
             time
             ,
             and
             lastly
             the
             Moon
             in
             a
             moneth
             .
             Now
             I
             say
             ,
             it
             is
             impossible
             by
             the
             longest
             Tub
             ,
             that
             the
             greatest
             Artist
             can
             make
             ,
             to
             discern
             the
             motion
             of
             the
             inferior
             Planets
             ,
             far
             less
             the
             motion
             of
             the
             superior
             ,
             either
             in
             Minuts
             or
             in
             Seconds
             ,
             and
             that
             by
             reason
             of
             the
             great
             ta●dity
             ,
             and
             slowness
             of
             the
             motion
             .
             Notwithstanding
             of
             this
             ,
             I
             am
             induced
             to
             think
             ,
             that
             the
             retrograde
             motion
             of
             the
             Moon
             might
             be
             discerned
             ,
             at
             least
             in
             Minuts
             .
             For
             evincing
             of
             this
             ,
             let
             us
             suppose
             which
             is
             true
             ,
             that
             the
             Sun
             runs
             from
             East
             to
             West
             half
             a
             degree
             in
             two
             Minuts
             of
             time
             ,
             seing
             in
             an
             hour
             he
             runs
             15
             degrees
             .
             Next
             ,
             that
             the
             Moon
             goes
             about
             the
             Zodiack
             in
             27
             dayes
             and
             7
             hours
             ,
             namely
             from
             that
             same
             point
             ,
             to
             that
             point
             again
             ,
             and
             consequently
             runs
             back
             every
             day
             13
             degrees
             and
             about
             
             10
             Minuts
             .
             By
             this
             account
             ,
             she
             must
             retrograde
             half
             a
             degree
             ,
             and
             about
             2
             minuts
             of
             a
             degree
             every
             hour
             .
             The
             Sun
             then
             runs
             half
             a
             degree
             in
             two
             Minuts
             ,
             and
             the
             Moon
             half
             a
             degree
             in
             60
             Minuts
             ;
             therefore
             the
             Moon
             must
             be
             30
             times
             slower
             in
             her
             retrograde
             motion
             ,
             than
             the
             Sun
             is
             in
             his
             diurnal
             motion
             .
             Let
             us
             suppose
             next
             ,
             as
             I
             observed
             with
             a
             Tub
             12
             foot
             long
             ,
             that
             the
             image
             of
             the
             Sun
             runs
             the
             eighth
             part
             of
             an
             inch
             every
             second
             ,
             and
             consequently
             ,
             seven
             inches
             and
             an
             half
             ,
             in
             a
             Minut
             :
             then
             must
             the
             image
             of
             the
             Moon
             with
             that
             same
             Telescope
             ,
             run
             the
             thirtieth
             part
             of
             seven
             inches
             and
             a
             half
             in
             a
             Minut
             ,
             seing
             she
             runs
             30
             times
             slowlier
             ;
             therefore
             in
             every
             Minut
             of
             time
             she
             must
             advance
             the
             fourth
             part
             of
             an
             inch
             ,
             which
             will
             be
             very
             sensible
             .
             Though
             we
             grant
             ,
             that
             the
             Moon
             hath
             no
             retrograde
             motion
             properly
             ,
             yet
             by
             comparing
             the
             diurnal
             Motion
             of
             the
             Moon
             ,
             that
             's
             slower
             ,
             to
             the
             diurnal
             motion
             of
             the
             Sun
             ,
             that
             's
             swifter
             ,
             we
             shall
             really
             find
             the
             thing
             it self
             .
             Therefore
             in
             the
             time
             of
             a
             
               Solar
               Eclipse
            
             ,
             this
             retrograde
             motion
             is
             conspicuous
             ,
             which
             by
             an
             ordinary
             Telescope
             may
             be
             discerned
             in
             Minuts
             .
             Assoon
             then
             as
             the
             East
             side
             of
             the
             Moon
             ,
             begins
             to
             enter
             upon
             the
             West
             side
             of
             the
             Sun
             (
             the
             greater
             the
             Eclipse
             be
             ,
             it
             is
             the
             better
             )
             observe
             ,
             and
             you
             will
             find
             the
             one
             image
             ,
             which
             will
             be
             black
             ,
             cover
             the
             other
             by
             degrees
             ,
             that
             's
             splendid
             ,
             and
             run
             in
             every
             minut
             of
             time
             ,
             the
             fourth
             part
             of
             an
             inch
             of
             the
             Suns
             diameter
             ,
             provided
             alwayes
             ,
             that
             the
             Sun
             run
             the
             eighth
             part
             of
             an
             inch
             in
             a
             second
             .
          
        
         
           
           
             OBSERVATION
             IV.
             
          
           
             UPon
             Tuesday
             the
             19.
             of
             Iuly
             1670
             ,
             the
             following
             Experiment
             was
             made
             .
             In
             the
             middle
             Marches
             between
             Scotland
             and
             England
             ,
             there
             is
             a
             long
             tract
             of
             Hills
             ,
             that
             run
             from
             Flowdon
             ,
             many
             miles
             South
             and
             South-west
             ,
             amongst
             the
             which
             ,
             the
             Mountain
             Cheviot
             is
             famous
             beyond
             ,
             and
             conspicuous
             above
             all
             the
             rest
             for
             altitude
             ,
             from
             whose
             top
             a
             man
             may
             discern
             with
             one
             turning
             of
             his
             eye
             ,
             the
             whole
             Sea-coast
             from
             New-castle
             to
             Berwick
             ,
             much
             of
             Northumberland
             ,
             and
             very
             many
             Leagues
             into
             the
             great
             
               German
               Ocean
            
             :
             the
             whole
             Mers
             and
             Teviotdale
             ,
             from
             the
             foot
             of
             Tweed
             ,
             to
             very
             near
             the
             head
             of
             it
             :
             Lauderdale
             ,
             and
             Lammer-moor
             ,
             and
             Pentland-hills
             above
             Edinburgh
             .
             The
             North
             side
             of
             this
             Mountain
             is
             pretty
             steep
             ,
             yet
             easie
             to
             climb
             ,
             either
             with
             men
             or
             horse
             .
             The
             top
             is
             spacious
             ,
             large
             and
             broad
             ,
             and
             all
             covered
             with
             a
             Flow-moss
             ,
             which
             runs
             very
             many
             miles
             South
             .
             When
             a
             man
             rides
             over
             it
             ,
             it
             rises
             and
             falls
             .
             'T
             is
             easie
             to
             thrust
             a
             Lance
             over
             the
             head
             in
             it
             .
             The
             sides
             of
             this
             Hill
             abounds
             with
             excellent
             Well-springs
             ,
             which
             are
             the
             original
             of
             several
             Torrents
             ,
             amongst
             the
             which
             Colledge-Water
             is
             famous
             ,
             upon
             which
             ,
             not
             a
             mile
             from
             the
             foot
             of
             this
             Mountain
             is
             White-hall
             .
             The
             adjacent
             Hills
             are
             for
             the
             most
             part
             green
             ,
             and
             excellent
             for
             the
             pasturage
             of
             Cattel
             .
             Not
             many
             years
             ago
             ,
             the
             whole
             Valleys
             near
             the
             foot
             of
             Cheviot
             ,
             were
             Forrests
             abounding
             with
             Wild-Deer
             .
          
           
             Upon
             the
             highest
             part
             of
             this
             Mountain
             was
             erected
             the
             
               Torricellian
               Experiment
            
             for
             weighing
             of
             the
             Air
             ,
             where
             we
             found
             the
             altitude
             of
             the
             
               Mercurial
               Cylinder
            
             27
             inches
             and
             an
             half
             .
             The
             Air
             was
             dry
             and
             clear
             ,
             and
             no
             wind
             .
             In
             our
             Valley-Countreys
             ,
             near
             to
             the
             Sea-Coast
             ,
             in
             such
             
             Weather
             ,
             we
             find
             the
             altitude
             29
             inches
             and
             an
             half
             .
             When
             this
             difference
             was
             found
             ,
             care
             was
             taken
             to
             seal
             up
             closly
             with
             Bee-wax
             ,
             mixed
             with
             Turpentine
             ,
             the
             orifice
             of
             the
             Vessel
             ,
             that
             contained
             the
             stagnant
             Mercury
             ,
             and
             thorow
             which
             the
             end
             of
             the
             Pipe
             went
             down
             .
             This
             being
             done
             with
             as
             great
             exactness
             as
             could
             be
             ,
             it
             was
             carried
             to
             the
             foot
             of
             the
             Mountain
             in
             a
             Frame
             of
             Wood
             ,
             made
             on
             purpose
             ,
             and
             there
             opening
             the
             mouth
             of
             the
             Vessel
             ,
             we
             found
             the
             Mercury
             to
             rise
             an
             inch
             and
             a
             quarter
             higher
             than
             it
             was
             .
             The
             reason
             of
             this
             strange
             Phenomenon
             must
             be
             this
             ,
             namely
             a
             greater
             Pressure
             of
             the
             Air
             at
             the
             foot
             of
             the
             Hill
             ,
             than
             upon
             the
             top
             :
             even
             as
             there
             is
             a
             greater
             Pressure
             of
             Water
             in
             a
             surface
             40
             fathom
             deep
             ,
             than
             in
             a
             surface
             20
             fathom
             deep
             .
             'T
             is
             not
             to
             be
             doubted
             .
             but
             if
             the
             root
             of
             the
             Mountain
             had
             been
             as
             low
             as
             the
             Sea
             Coast
             ,
             or
             as
             the
             surface
             of
             Tweed
             at
             Kelso
             ,
             the
             
               Mercurial
               Cylinder
            
             would
             have
             been
             higher
             .
             This
             way
             of
             observing
             ,
             seems
             to
             be
             better
             than
             the
             common
             :
             for
             while
             the
             Baroscope
             is
             carried
             up
             and
             down
             the
             Hill
             ,
             without
             stopping
             the
             orifice
             of
             the
             Vessel
             ,
             that
             contains
             the
             stagnant
             Mercury
             ,
             the
             Cylinder
             makes
             such
             reciprocations
             ,
             by
             the
             agitation
             of
             a
             mans
             body
             ,
             that
             sometimes
             abundance
             of
             Air
             is
             seen
             to
             ascend
             up
             thorow
             the
             Pipe
             ,
             which
             in
             effect
             makes
             the
             Cylinder
             shorter
             than
             it
             ought
             to
             be
             .
             But
             if
             so
             be
             ,
             the
             end
             of
             the
             Pipe
             be
             immerged
             among
             Quick-silver
             ,
             contained
             in
             a
             Glass
             with
             a
             narrow
             orifice
             ,
             so
             that
             it
             may
             be
             stopped
             compleatly
             ,
             you
             will
             find
             no
             reciprocations
             at
             all
             .
             And
             to
             make
             all
             things
             the
             more
             sure
             ,
             the
             Glass
             may
             be
             filled
             up
             either
             with
             Mercury
             ,
             or
             with
             Water
             above
             the
             Mercury
             ;
             by
             which
             means
             the
             Cylinder
             in
             the
             down-coming
             ,
             or
             in
             the
             up-going
             shall
             remain
             immoveable
             .
             Besides
             the
             stopping
             of
             the
             orifice
             of
             the
             said
             Glass
             ,
             you
             may
             have
             a
             wider
             Vessel
             ,
             
             that
             may
             receive
             the
             same
             Glass
             into
             it
             ,
             and
             it
             being
             full
             of
             Water
             ,
             may
             so
             cover
             the
             sealed
             orifice
             ,
             that
             there
             shall
             be
             no
             hazard
             of
             any
             Air
             coming
             in
             .
             Or
             this
             Experiment
             may
             be
             first
             tried
             at
             the
             root
             of
             the
             Hill
             ,
             and
             having
             stopped
             compleatly
             the
             mouth
             of
             the
             Vessel
             ,
             the
             whole
             Engine
             may
             be
             carried
             up
             to
             the
             top
             ,
             where
             you
             will
             find
             the
             Mercury
             subside
             and
             fall
             down
             so
             much
             ;
             namely
             after
             the
             said
             orifice
             is
             opened
             :
             for
             as
             the
             stopping
             of
             the
             orifice
             at
             the
             root
             of
             the
             Hill
             ,
             is
             the
             cause
             ,
             why
             that
             same
             degree
             of
             Pressure
             remains
             in
             the
             stagnant
             Liquor
             ;
             so
             the
             opening
             of
             it
             upon
             the
             top
             of
             the
             Hill
             ,
             is
             the
             cause
             why
             it
             becomes
             less
             .
          
           
             This
             Experiment
             lets
             us
             see
             ,
             that
             the
             Pressure
             of
             the
             Air
             seems
             to
             be
             as
             the
             Pressure
             of
             the
             Water
             ,
             namely
             the
             further
             down
             the
             greater
             ;
             and
             the
             further
             up
             the
             less
             :
             and
             therefore
             ,
             as
             by
             coming
             up
             to
             the
             top
             of
             the
             Water
             ,
             there
             is
             no
             more
             Pressure
             ,
             so
             by
             coming
             up
             to
             the
             top
             of
             the
             Air
             ,
             there
             is
             no
             more
             weight
             in
             it
             ;
             which
             in
             effect
             sayes
             ,
             that
             the
             Air
             hath
             a
             determinat
             hight
             ,
             as
             the
             Water
             hath
             .
             From
             this
             Experiment
             we
             cannot
             learn
             the
             determinat
             hight
             of
             the
             Air
             ,
             because
             the
             definit
             hight
             of
             the
             Mountain
             is
             not
             known
             .
             I
             know
             there
             are
             some
             ,
             who
             think
             that
             the
             Air
             is
             indefinitly
             extended
             ,
             as
             if
             forsooth
             ,
             the
             Firmament
             of
             fixed
             Stars
             were
             the
             limits
             of
             it
             ,
             but
             I
             suppose
             it
             is
             hard
             to
             make
             it
             out
             .
          
        
         
           
             OBSERVATION
             V.
             
          
           
             JUne
             5.
             1670.
             
             I
             observed
             the
             Sun
             within
             3
             minuts
             of
             setting
             ,
             to
             have
             a
             perfect
             
               oval
               figure
            
             ,
             the
             two
             ends
             lying
             level
             with
             the
             Horizon
             .
             His
             colour
             was
             not
             red
             as
             ordinarily
             ,
             but
             bright
             and
             clear
             ,
             as
             if
             he
             had
             been
             in
             the
             
             Meridian
             :
             neither
             was
             the
             Sky
             red
             ,
             but
             clear
             also
             .
             And
             by
             the
             help
             of
             the
             
               Pendulum
               Clock
            
             ,
             I
             have
             observed
             his
             body
             to
             be
             longer
             in
             setting
             than
             it
             ought
             ,
             by
             eight
             minuts
             ,
             and
             sometimes
             by
             ten
             ,
             and
             his
             Diameter
             longer
             in
             going
             out
             of
             sight
             than
             it
             ought
             ,
             by
             two
             ,
             and
             sometimes
             by
             three
             minuts
             .
             The
             reason
             of
             these
             Phenomena
             ,
             must
             be
             the
             Refraction
             unquestionably
             .
          
        
         
           
             OBSERVATION
             VI.
             
          
           
             UPon
             Saturday
             evening
             the
             30
             of
             Iuly
             1670
             ,
             and
             the
             night
             following
             ,
             till
             about
             two
             a
             Clock
             in
             the
             Sabbath
             morning
             ,
             there
             fell
             out
             a
             considerable
             rain
             ,
             with
             great
             thunder
             ,
             and
             many
             lightnings
             .
             About
             Sun-set
             ,
             the
             convocation
             of
             black
             clouds
             appeared
             first
             towards
             the
             Horizon
             in
             the
             South-west
             ,
             with
             several
             lightnings
             ;
             and
             the
             wind
             blowing
             from
             that
             point
             ,
             carried
             the
             clouds
             and
             rain
             over
             Mid
             and
             East-Lothian
             ,
             towards
             the
             Firth
             and
             Sea-coast
             .
             About
             9
             a
             clock
             ,
             the
             whole
             Heavens
             almost
             were
             covered
             with
             dark
             clouds
             ,
             yet
             the
             rain
             was
             not
             very
             great
             ,
             neither
             were
             the
             
               thunder
               claps
            
             frequent
             ,
             but
             every
             fifth
             or
             
               sixth
               second
            
             of
             time
             ,
             a
             large
             and
             great
             lightning
             brake
             out
             .
             But
             before
             the
             
               thunder
               crack
            
             was
             heard
             ,
             which
             happened
             every
             fourth
             or
             fifth
             minut
             ,
             the
             lightning
             was
             so
             terrible
             for
             greatness
             ,
             and
             brightness
             ,
             that
             it
             might
             have
             bred
             astonishment
             .
             And
             because
             the
             night
             was
             very
             dark
             ,
             and
             the
             lightning
             very
             splendid
             ,
             a
             man
             might
             have
             perceived
             houses
             and
             co●n-fields
             at
             a
             great
             distance
             .
             And
             if
             any
             had
             resolved
             to
             catch
             it
             ,
             in
             the
             breaking
             out
             ,
             it
             did
             so
             dazle
             the
             eyes
             ,
             that
             for
             half
             a
             minut
             ,
             he
             was
             not
             able
             to
             see
             any
             thing
             about
             him
             .
          
           
             Sometimes
             the
             lightning
             that
             went
             before
             the
             thunder
             ,
             
             brake
             forth
             from
             the
             clouds
             ,
             like
             a
             long
             spout
             of
             fire
             ,
             or
             rather
             like
             a
             long
             flame
             raised
             high
             ,
             with
             a
             Smiths
             Bellows
             ,
             but
             did
             not
             continue
             long
             in
             sight
             .
             Such
             an
             one
             above
             the
             Firth
             was
             seen
             to
             spout
             downward
             upon
             the
             Sea.
             Sometimes
             there
             appeared
             from
             the
             one
             end
             of
             the
             cloud
             to
             the
             other
             ,
             an
             hiatus
             ,
             or
             wide
             opening
             ,
             all
             full
             of
             fire
             ,
             in
             form
             of
             a
             long
             furrow
             ,
             or
             branch
             of
             a
             River
             ,
             not
             straight
             ,
             but
             crooked
             .
             I
             suppose
             the
             breadth
             of
             it
             ,
             in
             it self
             ,
             would
             have
             been
             twenty
             pace
             and
             more
             ,
             and
             the
             length
             of
             it
             five
             or
             six
             hundred
             pace
             :
             the
             duration
             of
             it
             ,
             would
             have
             been
             about
             a
             second
             of
             time
             .
             Sometimes
             a
             man
             might
             have
             perceived
             the
             nether
             side
             of
             the
             cloud
             ,
             before
             the
             crack
             came
             ,
             all
             speckled
             with
             streams
             of
             fire
             ,
             here
             and
             there
             ,
             like
             the
             side
             of
             an
             Hill
             ,
             where
             Moor-burn
             is
             ,
             which
             brake
             forth
             into
             a
             lightning
             .
             But
             there
             was
             one
             ,
             after
             which
             followed
             a
             terrible
             thunder
             crack
             ,
             which
             far
             exceeded
             all
             the
             rest
             ,
             for
             quantity
             and
             splendor
             .
             It
             brake
             out
             from
             the
             cloud
             ,
             being
             shot
             from
             North
             to
             South
             ,
             in
             form
             of
             fire
             from
             a
             great
             Cannon
             ,
             but
             in
             so
             great
             quantity
             ,
             as
             if
             a
             Gun
             ten
             foot
             wide
             ,
             with
             500
             pound
             weight
             of
             Powder
             in
             it
             ,
             had
             been
             fired
             .
             And
             surely
             the
             lightning
             behoved
             to
             be
             far
             greater
             in
             it self
             ,
             seeing
             it
             appeared
             so
             great
             ,
             at
             so
             great
             a
             distance
             .
             It
             did
             not
             evanish
             in
             an
             instant
             ,
             like
             the
             fire
             of
             a
             Gun
             ,
             but
             continued
             about
             a
             second
             and
             an
             half
             ;
             by
             reason
             (
             it
             seems
             )
             that
             it
             could
             not
             break
             out
             all
             at
             once
             .
             This
             did
             so
             dazle
             the
             sight
             ,
             that
             for
             half
             a
             minut
             almost
             ,
             nothing
             was
             seen
             ,
             but
             like
             a
             white
             mist
             flying
             before
             the
             eyes
             .
             The
             whole
             Countrey
             about
             was
             seen
             distinctly
             .
          
           
             All
             these
             great
             lightnings
             were
             seen
             a
             considerable
             time
             ,
             before
             the
             crack
             was
             heard
             .
             Sometimes
             30
             seconds
             numbered
             by
             the
             
               Pendulum
               Clock
            
             interveened
             ,
             namely
             when
             the
             thunder
             was
             at
             a
             distance
             ,
             about
             7
             or
             8
             miles
             .
             Sometimes
             
             15
             or
             16
             only
             interveened
             .
             But
             when
             the
             thunder
             was
             just
             above
             our
             head
             ,
             no
             moe
             passed
             ,
             than
             7
             or
             8
             ,
             which
             seems
             to
             demonstrat
             ,
             that
             these
             thick
             black
             clouds
             ,
             out
             of
             which
             the
             thunder
             breaks
             ,
             are
             not
             a
             Scottish
             mile
             from
             the
             earth
             ,
             when
             they
             are
             directly
             above
             us
             .
          
           
             'T
             is
             observable
             ,
             that
             in
             all
             lightnings
             ,
             and
             thunderings
             ,
             there
             is
             no
             smoke
             to
             be
             seen
             ,
             which
             seems
             to
             evince
             ,
             that
             the
             matter
             whereof
             they
             are
             generated
             ,
             must
             be
             most
             pure
             ,
             and
             subtil
             .
             Who
             knows
             ,
             but
             this
             Countrey
             ,
             that
             abounds
             with
             Coal
             ,
             may
             occasion
             more
             thunder
             and
             lightnings
             ,
             than
             other
             places
             ,
             namely
             by
             sending
             up
             sulphurious
             exhalations
             to
             the
             middle
             region
             of
             the
             Air
             ,
             wherewith
             the
             Coal-mines
             abound
             .
          
        
         
           
             OBSERVATION
             VII
             .
          
           
             THis
             is
             a
             method
             for
             finding
             out
             the
             true
             South
             and
             North
             Points
             ,
             which
             are
             in
             effect
             very
             difficult
             to
             know
             .
             Take
             therefore
             four
             pieces
             of
             Timber
             ,
             each
             one
             of
             them
             five
             foot
             long
             ,
             and
             about
             six
             inches
             thick
             ,
             square-wise
             .
             Sharpen
             their
             ends
             ,
             and
             fix
             them
             so
             in
             the
             ground
             ,
             that
             they
             may
             stand
             Perpendicular
             ,
             and
             as
             near
             to
             South
             and
             North
             ,
             by
             a
             
               Magnetick
               Needle
            
             ,
             as
             may
             be
             .
             The
             place
             would
             be
             free
             of
             Trees
             ,
             or
             of
             any
             such
             impediment
             ,
             that
             it
             may
             have
             a
             free
             prospect
             of
             the
             Heavens
             .
             As
             for
             their
             distance
             one
             from
             another
             ,
             let
             the
             two
             North-most
             ,
             and
             the
             South-most
             be
             two
             foot
             asunder
             :
             let
             the
             two
             East-most
             ,
             and
             two
             West-most
             ,
             be
             but
             one
             foot
             ,
             making
             as
             they
             stand
             ,
             an
             
               oblong
               quadrangle
            
             .
             For
             keeping
             them
             equidistant
             above
             ,
             as
             well
             as
             below
             ,
             take
             four
             bars
             of
             Wood
             ,
             about
             three
             inches
             broad
             ,
             and
             one
             inch
             thick
             ,
             and
             nail
             them
             round
             about
             upon
             the
             four
             sides
             ,
             on
             each
             side
             one
             ,
             so
             that
             
             being
             nailed
             on
             Horizontally
             ,
             they
             may
             make
             
               right
               angles
            
             ,
             with
             the
             tops
             of
             the
             standards
             above
             .
             There
             are
             then
             for
             distinctions
             cause
             ,
             the
             North-bar
             ,
             and
             the
             South-bar
             ,
             that
             runs
             East
             and
             West
             ,
             and
             the
             East-bar
             ,
             and
             the
             West-bar
             ,
             that
             runs
             South
             and
             North
             ,
             There
             is
             here
             no
             difficulty
             in
             the
             thing
             it self
             ,
             but
             only
             in
             the
             fancy
             to
             conceive
             it
             .
             Besides
             these
             four
             ,
             there
             must
             be
             other
             four
             of
             the
             same
             form
             and
             fashion
             ,
             nailed
             on
             ●arder
             down
             about
             the
             middle
             of
             the
             four
             standards
             .
             Take
             next
             some
             small
             Brass
             Wyre
             strings
             ,
             such
             as
             are
             used
             in
             Virginals
             ,
             and
             fix
             one
             from
             the
             middle
             of
             the
             South-bar
             ,
             that
             's
             upmost
             ,
             to
             the
             middle
             of
             the
             South-bar
             just
             under
             it
             .
             Fix
             it
             so
             ,
             that
             it
             may
             be
             exactly
             Perpendicular
             ,
             which
             may
             be
             done
             ,
             with
             a
             great
             weight
             of
             Lead
             .
             Take
             a
             second
             Wyrestring
             ,
             and
             hang
             it
             plumb
             from
             the
             West
             end
             of
             the
             North-bar
             ,
             and
             another
             from
             the
             East
             end
             of
             the
             same
             Bar
             ,
             I
             mean
             the
             Bar
             that
             's
             nearest
             to
             the
             top
             .
             These
             three
             strings
             so
             fixed
             ,
             will
             go
             near
             to
             make
             an
             
               equilateral
               triangle
            
             .
          
           
             Now
             because
             the
             device
             is
             for
             finding
             out
             the
             Meridian
             by
             the
             Stars
             in
             the
             night
             time
             ,
             not
             by
             any
             indifferently
             ,
             but
             by
             these
             that
             are
             nearest
             to
             the
             Pole
             ,
             therefore
             observe
             in
             Iuly
             and
             August
             ,
             when
             the
             Guard-stars
             in
             the
             evening
             begin
             to
             come
             down
             towards
             the
             West
             ,
             and
             keeping
             closs
             one
             eye
             ,
             bring
             the
             other
             somewhat
             near
             to
             the
             South-most
             string
             ,
             and
             order
             your
             sight
             so
             ,
             that
             this
             string
             ,
             and
             the
             West-most
             string
             upon
             the
             North
             side
             ,
             may
             catch
             the
             foremost
             Guard-star
             in
             the
             down-coming
             ,
             when
             it
             is
             furthest
             West
             ,
             and
             there
             fix
             it
             .
             When
             the
             same
             Star
             is
             turning
             up
             towards
             the
             East
             ,
             catch
             it
             by
             the
             South-most
             string
             ,
             and
             the
             East-most
             string
             on
             the
             North
             side
             ,
             and
             your
             work
             is
             done
             ,
             if
             so
             be
             ,
             you
             divide
             exactly
             ,
             between
             the
             East-most
             and
             West-most
             ,
             and
             there
             hang
             a
             fourth
             string
             ,
             which
             
             with
             the
             string
             upon
             the
             South-side
             ,
             gives
             you
             the
             true
             South
             and
             North.
             For
             better
             understanding
             ,
             note
             first
             ,
             that
             ,
             when
             the
             Guard-stars
             are
             coming
             down
             ,
             or
             going
             up
             ,
             the
             Altitude
             varies
             quickly
             ,
             but
             the
             Azimuth
             ,
             or
             motion
             from
             East
             to
             West
             ,
             will
             not
             vary
             sometimes
             sensibly
             in
             two
             hours
             almost
             ,
             which
             is
             a
             great
             advantage
             in
             this
             case
             .
             But
             when
             you
             find
             out
             the
             Meridian
             with
             a
             Plain
             ,
             and
             a
             Perpendicular
             Stilus
             ,
             by
             the
             shadow
             of
             the
             Sun
             ,
             if
             it
             be
             not
             when
             he
             is
             about
             East
             and
             West
             ,
             the
             Azimuth
             alters
             mo●e
             than
             the
             Altitude
             ,
             wh●ch
             is
             a
             great
             disadvantage
             .
             Now
             its
             certain
             ,
             the
             slower
             the
             motion
             be
             from
             East
             to
             West
             of
             any
             Star
             ,
             it
             is
             the
             easier
             to
             observe
             ,
             and
             it
             is
             the
             more
             sure
             way
             .
             Note
             secondly
             ,
             that
             special
             care
             must
             be
             had
             ,
             to
             cause
             the
             strings
             hang
             Perpendicular
             .
             Note
             thirdly
             ,
             that
             before
             you
             begin
             your
             Observations
             ,
             the
             South-most
             string
             must
             be
             made
             immoveable
             ,
             but
             the
             East-most
             ,
             and
             West-most
             ,
             on
             the
             other
             side
             ,
             must
             not
             be
             so
             ,
             because
             as
             the
             Stars
             in
             going
             about
             move
             from
             East
             to
             West
             ,
             so
             must
             the
             said
             two
             strings
             be
             left
             at
             liberty
             ,
             to
             move
             a
             little
             hither
             and
             thither
             ,
             till
             the
             Observations
             be
             ended
             .
             Note
             fourthly
             ,
             that
             assoon
             as
             you
             perceive
             sensibly
             ,
             the
             foremost
             Guard-star
             to
             decline
             towards
             the
             West
             ,
             then
             you
             must
             begin
             to
             observe
             ,
             which
             is
             nothing
             else
             ,
             but
             to
             fix
             your
             eye
             so
             ,
             that
             the
             South-most
             and
             West-most
             string
             ,
             may
             cover
             the
             said
             Star.
             And
             because
             in
             coming
             down
             ,
             it
             goes
             West
             ,
             therefore
             ,
             let
             the
             West-most
             string
             move
             towards
             the
             left
             hand
             by
             degrees
             ,
             following
             the
             Star
             to
             its
             utmost
             ,
             till
             it
             be
             covered
             by
             them
             both
             .
             Follow
             the
             same
             method
             ,
             in
             observing
             the
             same
             Star
             in
             going
             up
             towards
             the
             East
             .
             Note
             fifthly
             ,
             that
             when
             you
             make
             the
             two
             strings
             cover
             the
             Star
             ,
             that
             which
             is
             nearest
             to
             the
             eye
             ,
             will
             appear
             transparent
             ,
             and
             of
             a
             larger
             size
             ,
             so
             that
             you
             may
             perceive
             distinctly
             
             thorow
             it
             ,
             not
             only
             the
             Star
             it self
             ,
             but
             the
             other●string
             also
             ,
             which
             is
             a
             great
             advantage
             .
             This
             is
             evident
             to
             any
             ,
             who
             holds
             a
             bended
             silk
             threed
             between
             their
             eye
             and
             a
             Star
             in
             the
             night
             time
             ;
             for
             when
             you
             direct
             your
             sight
             to
             the
             Star
             ,
             the
             string
             appears
             like
             the
             small
             string
             of
             a
             Virginal
             when
             it
             trembles
             .
             Note
             sixthly
             ,
             that
             in
             observing
             in
             a
             dark
             night
             ,
             you
             must
             have
             a
             Cut-throat
             ,
             that
             by
             the
             light
             of
             the
             candle
             you
             may
             perceive
             the
             strings
             .
             Some
             other
             things
             might
             be
             noted
             ,
             but
             you
             will
             find
             them
             better
             by
             experience
             ,
             than
             they
             can
             be
             exprest
             here
             .
          
           
             I
             named
             Iuly
             and
             August
             in
             the
             evening
             for
             observing
             the
             Guard-stars
             ,
             when
             they
             are
             West-most
             ,
             but
             there
             are
             several
             other
             seasons
             ,
             when
             this
             may
             be
             done
             as
             conveniently
             .
             They
             are
             East-most
             in
             the
             latter
             end
             of
             October
             ,
             and
             beginning
             of
             November
             about
             5
             or
             6
             a
             clock
             in
             the
             morning
             .
             If
             a
             man
             were
             desirous
             to
             make
             this
             observation
             quickly
             ,
             I
             suppose
             he
             might
             in
             the
             end
             of
             October
             ,
             find
             the
             said
             stars
             West-most
             in
             the
             evening
             ,
             and
             East-most
             the
             next
             morning
             .
             Besides
             the
             Guard-stars
             ,
             a
             man
             may
             make
             use
             of
             the
             Polar-star
             ;
             for
             as
             it
             goes
             higher
             ,
             and
             lower
             than
             the
             true
             Pole
             ,
             by
             2
             degrees
             and
             26
             minuts
             ,
             so
             it
             goes
             as
             much
             to
             the
             East
             ,
             and
             as
             much
             to
             the
             West
             ,
             once
             in
             24
             hours
             .
             In
             the
             end
             of
             Iuly
             ,
             you
             will
             find
             the
             Polar-star
             East-most
             ,
             about
             9
             a
             clock
             at
             night
             ,
             and
             in
             the
             end
             of
             Ianuary
             West-most
             at
             9
             a
             clock
             .
             Note
             ,
             that
             every
             month
             ,
             the
             fixed
             stars
             come
             sooner
             to
             the
             same
             place
             by
             two
             hours
             :
             therefore
             in
             the
             end
             of
             August
             the
             Polar-star
             must
             be
             West
             ,
             at
             7
             a
             clock
             at
             night
             ,
             and
             East
             at
             7
             a
             clock
             in
             the
             morning
             .
             When
             the
             Meridian
             is
             found
             out
             after
             this
             manner
             ,
             there
             is
             no
             Star
             or
             Planet
             can
             pass
             it
             ,
             but
             you
             may
             know
             exactly
             when
             ,
             be
             it
             never
             so
             high
             ,
             or
             never
             so
             low
             .
             For
             there
             is
             nothing
             to
             be
             done
             ,
             but
             to
             wait
             ,
             till
             the
             South-most
             and
             North-most
             
             most
             string
             cover
             the
             body
             of
             the
             Star.
             If
             it
             be
             the
             Sun
             ,
             hold
             up
             a
             white
             Paper
             ,
             behind
             the
             two
             strings
             ,
             and
             when
             their
             shadows
             do
             co-incide
             ,
             and
             are
             united
             ,
             then
             is
             his
             Center
             in
             the
             Meridian
             .
             I●
             the
             Sun
             do
             not
             shine
             clear
             ,
             as
             when
             he
             is
             under
             mist
             ,
             or
             a
             thin
             cloud
             ,
             you
             may
             exactly
             take
             him
             up
             in
             the
             Meridian
             ,
             with
             the
             two
             strings
             .
             This
             Frame
             will
             serve
             as
             well
             ,
             to
             know
             when
             any
             of
             the
             North
             Stars
             comes
             South
             ,
             or
             North
             ,
             and
             consequently
             when
             they
             are
             highest
             ,
             and
             when
             they
             are
             lowest
             :
             for
             being
             fixed
             in
             an
             open
             place
             of
             the
             Orchard
             ,
             there
             's
             no
             
               Celestial
               Body
            
             can
             pass
             the
             Meridian
             ,
             either
             on
             the
             one
             side
             ,
             or
             the
             other
             ,
             but
             it
             may
             be
             catched
             ,
             what
             ever
             the
             Altitude
             be
             ,
             and
             that
             most
             easily
             .
          
        
         
           
             OBSERVATION
             VIII
             .
          
           
             THere
             hath
             been
             much
             inquiry
             made
             by
             some
             anent
             the
             reason
             ,
             why
             the
             dead
             body
             of
             a
             man
             or
             beast
             ,
             riseth
             from
             the
             ground
             of
             a
             Water
             ,
             after
             it
             hath
             been
             there
             three
             or
             four
             days
             .
             But
             though
             many
             have
             endeavoured
             to
             solve
             the
             question
             ,
             yet
             the
             difficulty
             remains
             ;
             and
             in
             effect
             it
             cannot
             be
             answered
             ,
             without
             the
             knowledge
             of
             the
             foregoing
             Doctrine
             ,
             anent
             the
             nature
             of
             fluid
             Bodies
             .
             To
             find
             out
             the
             reason
             then
             of
             this
             Phenomenon
             ,
             consider
             ,
             that
             all
             Bodies
             ,
             are
             either
             naturally
             heavier
             then
             Water
             ,
             as
             Stone
             and
             Lead
             ,
             or
             naturally
             lighter
             ,
             as
             Wood
             and
             Timber
             .
             If
             they
             be
             heavier
             ,
             they
             sink
             :
             if
             they
             be
             lighter
             ,
             they
             swim
             .
             Now
             I
             say
             ,
             a
             mans
             body
             immediatly
             after
             he
             is
             drowned
             ,
             his
             belly
             being
             full
             of
             Water
             ,
             must
             go
             to
             the
             ground
             ,
             because
             in
             this
             case
             ,
             it
             will
             be
             found
             specifically
             or
             naturally
             heavier
             then
             Water
             .
             That
             's
             to
             say
             ,
             a
             mans
             body
             ,
             will
             be
             heavier
             ,
             than
             as
             much
             Water
             ,
             as
             is
             
             the
             bulk
             of
             a
             mans
             body
             .
             For
             pleasing
             the
             fancy
             ,
             imagine
             a
             Statue
             to
             be
             composed
             of
             Water
             ,
             with
             all
             the
             true
             dimensions
             of
             the
             person
             that
             's
             dead
             ,
             so
             that
             the
             one
             shall
             answer
             most
             exactly
             to
             all
             the
             dimensions
             of
             the
             other
             .
             In
             this
             case
             ,
             if
             you
             counterpoise
             them
             in
             a
             Ballance
             ,
             the
             real
             body
             ,
             that
             's
             made
             up
             of
             flesh
             ,
             blood
             ,
             and
             bones
             ,
             shall
             weigh
             down
             the
             other
             .
             But
             after
             this
             dead
             body
             hath
             lien
             a
             short
             time
             among
             the
             Water
             ,
             it
             presently
             begins
             to
             swell
             ,
             which
             is
             caused
             by
             the
             fermentation
             of
             the
             humors
             of
             the
             blood
             ,
             which
             goeth
             before
             putrefaction
             ,
             and
             after
             three
             or
             four
             dayes
             swells
             so
             great
             ,
             that
             in
             effect
             ,
             it
             becomes
             naturally
             lighter
             than
             Water
             ,
             and
             therefore
             riseth
             .
             That
             is
             to
             say
             ,
             take
             that
             body
             ,
             that
             is
             now
             swelled
             ,
             and
             as
             much
             bulk
             of
             Water
             ,
             as
             will
             be
             the
             precise
             quantity
             of
             it
             ,
             and
             having
             counterpoised
             them
             in
             a
             Ballance
             ,
             you
             will
             find
             the
             Water
             heavier
             than
             the
             body
             .
          
        
         
           
             OBSERVATION
             IX
             .
          
           
             UPon
             Thursday
             the
             25
             of
             August
             1670
             ,
             the
             following
             Experiment
             was
             made
             in
             a
             new
             Coal-sink
             ,
             on
             the
             West
             side
             of
             Tranent
             .
             When
             the
             Coal-hewers
             had
             digged
             down
             about
             6
             or
             7
             fathom
             ,
             they
             were
             interrupted
             sometimes
             with
             
               ill
               Air
            
             :
             therefore
             to
             know
             the
             power
             and
             force
             of
             the
             Damp
             ,
             we
             let
             down
             within
             the
             Bucket
             a
             Dog.
             When
             he
             had
             gone
             down
             about
             4
             fathom
             ,
             or
             middle
             Sink
             ,
             we
             found
             little
             or
             no
             alteration
             in
             him
             ,
             save
             only
             that
             he
             opened
             his
             mouth
             ,
             and
             had
             some
             difficulty
             in
             breathing
             ,
             which
             we
             perceived
             evidently
             :
             for
             no
             sooner
             he
             was
             pulled
             up
             to
             the
             top
             ,
             where
             the
             
               good
               Air
            
             was
             ,
             but
             he
             left
             off
             his
             gaping
             .
             We
             let
             him
             down
             next
             to
             the
             bottom
             ,
             where
             he
             tarried
             a
             pretty
             while
             ,
             but
             no
             more
             change
             we
             found
             in
             
             him
             than
             before
             .
             After
             this
             we
             let
             down
             a
             great
             quantity
             of
             Whins
             ,
             well
             kindled
             with
             a
             bold
             flame
             ,
             but
             they
             no
             sooner
             came
             to
             the
             middle
             of
             the
             sink
             ,
             but
             the
             flame
             was
             in
             an
             instant
             extinguished
             :
             and
             no
             sooner
             was
             the
             Bucket
             pulled
             up
             ,
             but
             they
             took
             fire
             again
             .
             This
             was
             5
             or
             6
             times
             tried
             ,
             with
             the
             same
             success
             .
             If
             we
             compare
             this
             Observation
             with
             the
             first
             ,
             we
             will
             find
             ,
             that
             all
             Damps
             are
             not
             of
             the
             same
             power
             and
             force
             ;
             but
             that
             some
             are
             stronger
             ,
             and
             kills
             men
             and
             beasts
             in
             an
             instant
             :
             and
             that
             others
             are
             less
             efficacious
             ,
             and
             more
             feeble
             ,
             and
             doth
             not
             so
             much
             hurt
             ,
             and
             that
             men
             may
             hazard
             to
             go
             down
             into
             a
             Sink
             ,
             where
             
               ill
               Air
            
             is
             ,
             even
             though
             fire
             be
             sometimes
             extinguished
             .
             We
             see
             next
             ,
             that
             these
             Damps
             doth
             not
             alwayes
             infect
             the
             whole
             Air
             of
             a
             Coal-pit
             ,
             but
             only
             a
             certain
             quantity
             :
             for
             sometimes
             it
             is
             found
             in
             the
             bottom
             ,
             sometimes
             in
             the
             middle
             .
             And
             we
             see
             lastly
             ,
             that
             they
             are
             not
             alwayes
             of
             long
             continuance
             :
             for
             it
             is
             found
             ,
             that
             though
             the
             Air
             be
             ill
             in
             the
             morning
             ,
             yet
             it
             may
             be
             good
             ere
             night
             ;
             and
             totally
             evanished
             ere
             the
             next
             day
             .
             We
             may
             add
             ,
             as
             was
             noted
             in
             the
             first
             Observation
             ,
             that
             these
             Damps
             depend
             much
             upon
             the
             scituation
             of
             the
             winds
             ,
             seing
             in
             strong
             Southerly
             winds
             ,
             they
             are
             frequently
             in
             these
             places
             .
          
        
         
           
             OBSERVATION
             X.
             
          
           
             OF
             these
             many
             excellent
             devices
             ,
             that
             have
             been
             found
             out
             of
             late
             ,
             the
             Air-pump
             is
             one
             ,
             first
             invented
             in
             Germany
             ,
             and
             afterwards
             much
             perfected
             in
             England
             by
             that
             Honourable
             Person
             Mr
             Boyl
             ,
             who
             for
             his
             pains
             ,
             and
             industry
             in
             making
             Experiments
             therewith
             ,
             deserves
             the
             thanks
             of
             all
             learned
             persons
             .
             Several
             trials
             hath
             been
             made
             of
             late
             by
             it
             ,
             some
             whereof
             ,
             are
             as
             follows
             .
             I
             took
             a
             slender
             
             Glass-tub
             about
             40
             inches
             long
             ,
             closs
             above
             ,
             and
             open
             below
             ,
             and
             filled
             it
             with
             VVater
             .
             I
             next
             inverted
             it
             ,
             and
             set
             the
             orifice
             of
             it
             ,
             just
             upon
             the
             mouth
             of
             the
             Brass-pipe
             ,
             that
             bends
             upward
             thorow
             the
             board
             ,
             whereon
             the
             Receiver
             useth
             to
             stand
             ,
             and
             cemented
             them
             together
             .
             At
             the
             first
             exsuction
             ,
             the
             whole
             VVater
             in
             the
             Pipe
             fell
             down
             ,
             and
             ran
             thorow
             the
             Brass-conduit
             to
             the
             Pump
             .
             Having
             for
             a
             short
             while
             stopped
             the
             passage
             ,
             and
             thrust
             down
             the
             Sucker
             ,
             I
             next
             opened
             it
             again
             ,
             and
             the
             Pump
             being
             full
             of
             VVater
             ,
             it
             was
             driven
             with
             a
             considerable
             force
             up
             thorow
             the
             Pipe
             ;
             yet
             was
             it
             not
             compleatly
             fill'd
             as
             before
             ,
             by
             reason
             of
             some
             Air
             ,
             that
             I
             saw
             in
             the
             top
             .
             After
             this
             was
             done
             ,
             with
             pleasure
             five
             or
             six
             times
             ,
             I
             opened
             the
             Stop-cock
             more
             quickly
             ,
             than
             I
             had
             used
             ,
             but
             the
             VVater
             ,
             by
             this
             means
             ,
             was
             so
             furiously
             driven
             up
             thorow
             the
             Tub
             ,
             that
             in
             effect
             ,
             it
             broke
             the
             end
             of
             it
             ,
             that
             was
             
               Hermetically
               sealed
            
             ;
             and
             the
             piece
             that
             flew
             off
             ,
             did
             hit
             the
             seiling
             so
             smartly
             ,
             that
             it
             rebounded
             a
             very
             far
             way
             .
             From
             this
             we
             see
             the
             reason
             ,
             why
             VVater
             falls
             not
             down
             from
             Vessels
             that
             have
             narrow
             necks
             ,
             though
             they
             be
             inverted
             ,
             because
             it
             's
             kept
             in
             by
             the
             force
             and
             power
             of
             the
             environing
             Air.
             'T
             is
             observable
             ,
             that
             though
             this
             Pipe
             had
             been
             30
             foot
             high
             ,
             yet
             the
             whole
             VVater
             in
             it
             would
             have
             subsided
             ,
             and
             fallen
             down
             ,
             with
             one
             exsuction
             .
          
           
             The
             next
             trial
             was
             with
             the
             help
             of
             a
             small
             Receiver
             ,
             which
             in
             effect
             was
             a
             real
             Cupping-glass
             .
             This
             had
             a
             hole
             made
             in
             the
             bottom
             of
             it
             ,
             and
             was
             cemented
             to
             the
             Brass-plate
             ,
             and
             the
             mouth
             of
             it
             looking
             upward
             ,
             had
             a
             lid
             for
             covering
             of
             it
             .
             I
             took
             next
             the
             lately
             mentioned
             Glass-pipe
             ,
             and
             filled
             it
             with
             good
             Brandy
             ,
             and
             having
             drowned
             the
             end
             of
             it
             among
             stagnant
             Brandy
             ,
             I
             set
             the
             Vessel
             wherein
             it
             was
             within
             the
             Receiver
             ,
             the
             Pipe
             coming
             up
             thorow
             
             the
             lid
             ,
             and
             having
             cemented
             it
             closly
             ,
             I
             made
             the
             first
             exsuction
             ,
             and
             found
             no
             descent
             of
             the
             Liquor
             from
             the
             top
             of
             the
             Tub.
             At
             the
             second
             ,
             it
             fell
             down
             about
             an
             inch
             .
             At
             the
             third
             ,
             it
             fell
             down
             four
             or
             five
             .
             But
             here
             appeared
             a
             great
             multitude
             of
             small
             Bubbles
             of
             Air
             ,
             like
             broken
             VVater
             ,
             near
             the
             top
             of
             the
             Pipe
             within
             .
             And
             besides
             this
             Phenomenon
             ,
             there
             ascended
             from
             the
             stagnant
             Liquor
             up
             thorow
             the
             Pipe
             ,
             an
             infinit
             number
             of
             small
             Bubbles
             ,
             no
             bigger
             than
             Pin-heads
             ,
             for
             a
             very
             large
             time
             .
             VVith
             a
             fourth
             exsuction
             ,
             it
             fell
             down
             within
             two
             or
             three
             inches
             of
             the
             
               stagnant
               Brandy
            
             .
             And
             thinking
             to
             make
             the
             one
             level
             with
             the
             other
             ,
             I
             made
             a
             fifth
             ;
             but
             here
             appeared
             a
             strang
             effect
             ,
             namely
             ,
             not
             only
             the
             whole
             Brandy
             in
             the
             Pipe
             subsided
             ,
             and
             was
             mingled
             with
             the
             
               stagnant
               Brandy
            
             ,
             but
             at
             this
             exsuction
             ,
             there
             came
             a
             great
             quantity
             of
             Air
             from
             the
             mouth
             of
             the
             Pipe
             ,
             and
             rose
             up
             thorow
             the
             
               stagnant
               Liquor
            
             in
             Bubbles
             .
             Having
             made
             another
             exsuction
             ,
             there
             came
             yet
             more
             Air
             out
             ,
             and
             so
             copiously
             ,
             that
             I
             thought
             there
             had
             been
             some
             leak
             in
             the
             Tub
             ,
             through
             which
             the
             outward
             Air
             had
             entered
             ;
             but
             knowing
             the
             contrary
             ,
             I
             continued
             Pumping
             a
             very
             long
             time
             ,
             till
             I
             found
             less
             and
             less
             come
             out
             ,
             and
             at
             length
             ,
             after
             near
             30
             exsuctions
             it
             ceased
             .
             This
             Air
             to
             appearance
             ,
             was
             so
             much
             as
             might
             have
             filled
             twenty
             Tubs
             ,
             every
             one
             of
             them
             as
             large
             ,
             as
             the
             Tub
             it
             came
             out
             of
             .
             And
             surely
             all
             of
             it
             came
             out
             from
             among
             the
             small
             quantity
             of
             Brandy
             that
             filled
             the
             Pipe
             ,
             and
             that
             environed
             the
             mouth
             of
             it
             ,
             I
             mean
             the
             
               stagnant
               Brandy
            
             ,
             both
             which
             would
             not
             have
             been
             eight
             spoonful
             .
             After
             this
             I
             opened
             the
             Stop-cock
             leasurely
             to
             let
             in
             the
             Air
             to
             the
             Receiver
             ;
             then
             did
             the
             Brandy
             climb
             up
             the
             Pipe
             slowly
             ,
             till
             it
             came
             near
             to
             the
             top
             ,
             and
             there
             made
             some
             little
             halt
             ,
             by
             reason
             of
             half
             an
             inch
             of
             Air
             that
             appeared
             
             there
             .
             But
             more
             and
             more
             Air
             coming
             into
             the
             Receiver
             ,
             that
             half
             inch
             in
             the
             top
             of
             the
             Pipe
             ,
             did
             so
             diminish
             ,
             that
             it
             appeared
             no
             bigger
             than
             the
             point
             of
             a
             Pin
             ,
             and
             was
             scarcely
             discernable
             to
             the
             eyes
             .
             What
             a
             strange
             and
             wonderful
             faculty
             of
             dilatation
             and
             contraction
             must
             be
             in
             the
             Air
             ,
             seing
             that
             which
             presently
             had
             filled
             the
             whole
             Tub
             ,
             that
             was
             40
             inches
             long
             ,
             and
             the
             sixth
             p●rt
             of
             an
             inch
             wide
             ,
             was
             contracted
             to
             as
             little
             room
             ,
             as
             the
             point
             of
             a
             Needle
             .
             And
             by
             making
             some
             new
             exsuctions
             ▪
             that
             small
             Atome
             of
             Air
             did
             so
             dilate
             it self
             again
             ,
             that
             ●t
             filled
             the
             same
             Tub
             ,
             and
             not
             only
             that
             ,
             but
             ,
             as
             formerly
             ,
             it
             bubbled
             out
             from
             the
             mouth
             of
             the
             Pipe
             several
             times
             .
          
           
             'T
             is
             to
             be
             observed
             ,
             that
             though
             at
             the
             first
             falling
             down
             of
             the
             Brandy
             ,
             it
             appeared
             like
             broken
             Water
             ,
             near
             the
             top
             of
             the
             Pipe
             within
             ,
             yet
             no
             such
             thing
             was
             seen
             the
             second
             time
             it
             fell
             down
             ;
             the
             reason
             is
             ,
             because
             by
             the
             first
             exsuctions
             ,
             it
             was
             well
             exhausted
             of
             its
             
               aërial
               particles
            
             .
             Once
             or
             twice
             I
             found
             ,
             after
             the
             Brandy
             within
             the
             Pipe
             was
             well
             freed
             of
             Air
             ,
             that
             no
             exsuctions
             could
             make
             it
             move
             from
             the
             top
             of
             the
             Tub
             ;
             and
             observed
             a
             round
             Bubble
             of
             Air
             to
             march
             up
             ,
             which
             when
             once
             it
             came
             to
             the
             top
             ,
             did
             separate
             the
             one
             from
             the
             other
             .
             If
             this
             hold
             good
             ,
             it
             seems
             to
             prove
             ,
             that
             neither
             Mercury
             ,
             nor
             any
             other
             Liquor
             would
             fall
             down
             in
             Pipes
             ,
             unless
             there
             were
             Air
             lurking
             amongst
             the
             parts
             to
             fill
             up
             the
             deserted
             space
             .
          
           
             From
             this
             Experiment
             we
             learn
             ,
             that
             no
             person
             can
             well
             apprehend
             or
             conceive
             ,
             how
             far
             ,
             and
             to
             what
             bounds
             the
             smallest
             part
             of
             Air
             is
             able
             to
             expand
             it self
             .
             And
             it
             proves
             evidently
             ,
             that
             when
             the
             Receiver
             is
             as
             much
             emptied
             as
             it
             can
             be
             ,
             by
             the
             Art
             of
             man
             ,
             yet
             it
             is
             full
             of
             Air
             compleatly
             .
          
           
           
             The
             third
             trial
             was
             after
             this
             manner
             :
             I
             set
             within
             the
             Receiver
             a
             little
             Glass
             half
             full
             of
             Brandy
             ,
             and
             the
             lid
             being
             cemented
             on
             ,
             I
             began
             to
             pump
             ,
             but
             there
             appeared
             no
             alteration
             at
             the
             first
             exsuction
             .
             At
             the
             second
             ,
             I
             perceived
             a
             great
             company
             of
             very
             small
             Bubbles
             ,
             that
             for
             a
             long
             time
             ascended
             from
             the
             body
             of
             it
             ,
             and
             came
             to
             the
             surface
             .
             At
             the
             third
             ,
             they
             were
             so
             frequent
             ,
             and
             great
             ,
             that
             the
             Brandy
             appeared
             to
             seeth
             and
             boil
             ,
             and
             by
             reason
             of
             the
             great
             ebullitions
             ,
             much
             of
             it
             ran
             over
             the
             lips
             of
             the
             Glass
             ,
             and
             fell
             into
             the
             bottom
             of
             the
             Receiver
             .
             This
             boiling
             continued
             for
             the
             space
             of
             7
             or
             8
             exsuctions
             ,
             and
             by
             process
             of
             time
             ,
             the
             Bubbles
             grew
             fewer
             and
             fewer
             ,
             and
             when
             about
             30
             or
             40
             exsuctions
             were
             made
             ,
             no
             more
             appeared
             .
             With
             this
             same
             sort
             of
             Brandy
             ,
             I
             filled
             the
             fore-named
             Pipe
             ,
             and
             set
             it
             within
             the
             Receiver
             ,
             the
             mouth
             of
             the
             Tub
             being
             guarded
             with
             the
             same
             sort
             of
             Liquor
             .
             When
             it
             began
             to
             subside
             ,
             there
             appeared
             no
             Bubbles
             near
             the
             top
             as
             before
             :
             the
             reason
             seems
             to
             be
             ,
             because
             the
             Brandy
             was
             well
             exhausted
             from
             its
             
               aërial
               particles
            
             .
             For
             a
             fourth
             trial
             ,
             I
             filled
             the
             same
             Tub
             with
             Ale
             ,
             that
             was
             only
             5
             or
             6
             dayes
             old
             ,
             and
             drowning
             the
             end
             of
             it
             among
             stagnant
             Ale
             of
             the
             same
             kind
             ,
             I
             began
             to
             Pump
             ,
             and
             found
             ,
             that
             assoon
             as
             the
             Liquor
             began
             to
             subside
             ,
             from
             the
             top
             of
             the
             Pipe
             ,
             the
             whole
             Ale
             within
             the
             Pipe
             ,
             almost
             turned
             into
             Air
             ,
             and
             Froth
             ,
             and
             so
             many
             large
             Bubbles
             came
             up
             from
             the
             stagnant
             Liquor
             that
             I
             thought
             the
             whole
             was
             converted
             into
             Air.
             It
             was
             most
             pleasant
             to
             behold
             their
             several
             forms
             and
             shapes
             ,
             their
             order
             and
             motion
             .
             This
             same
             Tub
             being
             filled
             with
             
               sweet
               milk
            
             ,
             I
             found
             very
             few
             Bubbles
             in
             it
             ,
             when
             by
             the
             exsuctions
             ,
             it
             began
             to
             subside
             .
             I
             likewise
             took
             a
             little
             Glass-viol
             ,
             and
             fill'd
             the
             half
             of
             it
             full
             with
             common
             Ale
             ,
             and
             set
             it
             within
             the
             Receiver
             .
             At
             the
             first
             exsuction
             ,
             
             Bubbles
             of
             Air
             began
             to
             rise
             out
             of
             it
             .
             At
             the
             second
             and
             third
             ,
             they
             did
             so
             multiply
             ,
             that
             they
             fill'd
             the
             other
             half
             of
             the
             Glass
             ,
             and
             ran
             over
             ,
             as
             a
             Pot
             doth
             when
             it
             boileth
             .
             And
             before
             I
             could
             exhaust
             all
             the
             Air
             out
             of
             it
             ,
             moe
             than
             20
             exsuctions
             passed
             .
          
           
             For
             a
             fifth
             trial
             ,
             I
             filled
             the
             often
             mentioned
             Pipe
             with
             Fountain-water
             ,
             and
             when
             it
             began
             to
             subside
             by
             Pumping
             ,
             I
             found
             it
             leave
             much
             Air
             behind
             it
             .
             But
             all
             the
             exsuctions
             I
             made
             ,
             could
             not
             make
             the
             Water
             of
             the
             Pipe
             go
             so
             low
             ,
             as
             the
             stagnant
             Water
             ,
             by
             which
             impediment
             ,
             I
             could
             Pump
             no
             Air
             out
             of
             the
             Pipe
             ,
             as
             I
             did
             ,
             while
             I
             made
             use
             of
             Brandy
             .
             This
             tell
             us
             ,
             that
             either
             there
             is
             not
             so
             much
             Air
             lurking
             among
             Water
             ,
             as
             among
             Brandy
             ,
             or
             that
             the
             Air
             among
             this
             ,
             hath
             a
             more
             expansive
             faculty
             in
             it
             ,
             than
             the
             Air
             that
             lurks
             among
             Water
             .
             If
             any
             think
             ,
             that
             it
             is
             not
             true
             and
             real
             Air
             ,
             which
             comes
             from
             the
             Brandy
             ,
             but
             rather
             the
             Spirits
             of
             it
             ,
             which
             evaporats
             .
             I
             answer
             ,
             if
             a
             man
             tast
             this
             Brandy
             that
             's
             exhausted
             of
             its
             
               aërial
               particles
            
             ,
             he
             will
             find
             it
             as
             strong
             ,
             as
             before
             ,
             which
             could
             not
             be
             ,
             if
             the
             Spirits
             were
             gone
             ,
          
           
             For
             a
             sixth
             trial
             ,
             I
             took
             a
             Frog
             and
             inclosed
             her
             within
             the
             Receiver
             .
             But
             all
             the
             exsuctions
             I
             was
             able
             to
             make
             ,
             could
             not
             so
             much
             as
             trouble
             her
             .
             Only
             ,
             when
             the
             Receiver
             was
             exhausted
             ,
             I
             perceived
             her
             sides
             to
             swell
             very
             big
             ,
             and
             when
             the
             Stop-cock
             was
             turned
             ,
             to
             let
             in
             the
             Air
             again
             ,
             her
             sides
             clapped
             closs
             together
             .
             I
             observed
             likewise
             ,
             when
             the
             Air
             was
             pretty
             well
             Pumped
             out
             ,
             that
             the
             Frog
             had
             no
             respirations
             ,
             or
             if
             there
             were
             any
             ,
             they
             were
             very
             insensible
             .
             The
             next
             day
             ,
             after
             she
             had
             been
             prisoner
             in
             the
             Receiver
             24
             hours
             ,
             I
             began
             again
             to
             Pump
             ,
             and
             after
             several
             exsuctions
             ,
             her
             sides
             swell'd
             pretty
             great
             ,
             and
             I
             perceived
             her
             open
             her
             mouth
             wide
             ,
             and
             somewhat
             like
             a
             
             Bag
             endeavouring
             to
             come
             out
             ,
             which
             surely
             hath
             been
             some
             of
             her
             noble
             parts
             ,
             striving
             to
             dilate
             themselves
             ,
             the
             body
             being
             freed
             of
             all
             Pressure
             from
             the
             ambient
             Air.
             
          
        
         
           
             OBSERVATION
             XI
             .
          
           
             TAke
             a
             slender
             chord
             ,
             about
             4
             or
             5
             yards
             in
             length
             ,
             and
             fasten
             the
             middle
             of
             it
             to
             the
             seiling
             of
             a
             Room
             with
             a
             nail
             ,
             so
             that
             the
             two
             ends
             of
             it
             may
             hang
             down
             equally
             .
             Take
             next
             a
             piece
             of
             Wood
             ,
             two
             or
             three
             foot
             long
             ,
             two
             inches
             broad
             ,
             and
             one
             inch
             thick
             ,
             and
             boring
             an
             hole
             in
             each
             end
             of
             it
             ,
             put
             through
             the
             two
             ends
             of
             the
             chord
             ,
             and
             fasten
             them
             with
             knots
             ;
             but
             so
             ,
             that
             the
             piece
             of
             Wood
             may
             ly
             Horizontal
             ,
             and
             be
             in
             a
             manner
             a
             Pendulum
             to
             swing
             from
             the
             one
             end
             of
             the
             Chamber
             to
             the
             other
             .
             Take
             next
             a
             Bullet
             of
             Lead
             or
             Iron
             ,
             about
             20
             or
             24
             ounces
             ,
             and
             lay
             it
             upon
             the
             said
             piece
             of
             Wood
             :
             but
             because
             it
             cannot
             well
             ly
             ,
             without
             falling
             off
             ,
             therefore
             nail
             upon
             the
             ends
             ,
             and
             the
             sides
             of
             the
             Timber
             ,
             four
             pieces
             of
             Sticks
             ,
             on
             each
             end
             one
             ,
             and
             on
             each
             side
             one
             ,
             as
             Ledgets
             ,
             for
             keeping
             the
             Bullet
             from
             falling
             off
             .
             All
             things
             being
             thus
             ordered
             ,
             draw
             up
             the
             piece
             of
             Wood
             towards
             the
             one
             side
             of
             the
             Room
             ,
             by
             which
             means
             losing
             its
             horizontal
             position
             ,
             it
             will
             ly
             declining-wise
             ,
             like
             the
             roof
             of
             an
             house
             .
             In
             this
             position
             ,
             lay
             the
             Iron
             Bullet
             in
             the
             upmost
             end
             of
             it
             ,
             and
             then
             let
             them
             both
             pass
             from
             your
             fingers
             ,
             the
             one
             end
             of
             the
             Wood
             going
             foremost
             ,
             and
             you
             will
             find
             it
             swing
             towards
             the
             other
             side
             of
             the
             house
             ,
             and
             return
             again
             ,
             as
             a
             Pendulum
             .
             This
             motion
             ,
             if
             the
             Wood
             be
             well
             guided
             in
             its
             vibrations
             ,
             will
             last
             perpetually
             ,
             because
             in
             its
             moving
             down
             ,
             the
             Bullet
             is
             hurled
             from
             the
             one
             end
             of
             the
             Wood
             ,
             to
             the
             other
             ,
             and
             hits
             it
             so
             smartly
             ,
             that
             it
             begets
             in
             it
             ,
             
             an
             impulse
             ,
             whereby
             it
             is
             carried
             farder
             up
             ,
             than
             it
             would
             be
             ,
             without
             it
             .
             By
             this
             means
             ,
             the
             vibrations
             get
             not
             liberty
             to
             diminish
             ,
             but
             all
             of
             them
             are
             kept
             of
             the
             same
             length
             .
             In
             the
             second
             vibration
             ,
             the
             same
             Bullet
             is
             hurled
             back
             again
             to
             the
             other
             end
             ,
             and
             hiting
             it
             with
             all
             its
             weight
             ,
             creats
             a
             second
             impulse
             ,
             wherewith
             the
             Wood
             is
             carried
             ,
             as
             far
             up
             as
             the
             point
             it
             was
             first
             demitted
             from
             .
          
           
             Though
             this
             may
             seem
             a
             pretty
             device
             to
             please
             the
             fancy
             ,
             that
             's
             many
             times
             deceived
             ,
             while
             things
             are
             presented
             to
             it
             ,
             by
             way
             of
             speculation
             ,
             yet
             upon
             tryal
             and
             experience
             ,
             there
             will
             be
             found
             ,
             an
             unspeakeable
             difficulty
             :
             and
             it
             's
             such
             an
             one
             ,
             that
             a
             man
             would
             not
             readily
             think
             upon
             .
             I
             said
             ,
             that
             when
             the
             Wood
             was
             let
             go
             ,
             and
             was
             in
             passing
             down
             ,
             the
             Bullet
             in
             it
             ,
             would
             hurl
             down
             ,
             and
             hit
             the
             oppsite
             end
             ,
             and
             beget
             an
             impulse
             ;
             but
             there
             is
             no
             such
             thing
             ,
             for
             verily
             ,
             though
             the
             Bullet
             be
             laid
             upon
             a
             very
             declining
             plain
             Board
             ,
             whereupon
             no
             man
             could
             imagine
             a
             round
             body
             could
             ly
             ,
             yet
             all
             the
             time
             the
             Board
             is
             in
             swinging
             ,
             from
             the
             one
             side
             of
             the
             Chamber
             ,
             to
             the
             other
             ,
             and
             consequently
             ,
             sometimes
             under
             an
             horizontal
             ,
             and
             somtimes
             under
             an
             declining
             position
             ,
             the
             Bullet
             lies
             dead
             in
             the
             place
             ,
             where
             you
             first
             placed
             it
             .
             This
             Observation
             is
             not
             so
             much
             for
             a
             perpetual
             motion
             ,
             as
             for
             finding
             out
             the
             reason
             of
             this
             pretty
             Phenomenon
             ,
             namely
             ,
             what
             's
             the
             cause
             ,
             why
             the
             Bullet
             ,
             that
             cannot
             ly
             upon
             a
             reclining
             Board
             ,
             while
             it
             's
             without
             motion
             ,
             shall
             now
             ly
             upon
             it
             ,
             while
             it
             's
             under
             motion
             ?
             What
             is
             more
             difficult
             ,
             and
             nice
             ,
             to
             ly
             upon
             any
             thing
             ,
             that
             declines
             from
             a
             levell
             ,
             than
             Quick-silver
             ;
             yet
             lay
             never
             so
             much
             of
             it
             upon
             this
             Board
             ,
             while
             it
             is
             swinging
             ,
             it
             shall
             ly
             dead
             ,
             and
             without
             motion
             .
             But
             no
             sooner
             you
             stop
             the
             motion
             of
             the
             wood
             ,
             
             but
             assoon
             ,
             the
             Bullet
             ,
             or
             the
             Quick-silver
             ,
             is
             hurled
             ,
             either
             this
             way
             ,
             or
             that
             way
             .
          
        
         
           
             OBSERVATON
             XII
             .
          
           
             I
             Find
             it
             mentioned
             by
             some
             learned
             persons
             ,
             that
             when
             a
             Ship
             is
             under
             Sail
             ,
             if
             a
             stone
             be
             demitted
             from
             the
             top
             of
             the
             Mast
             ,
             it
             will
             move
             down
             in
             a
             line
             parallel
             with
             it
             ,
             and
             fall
             at
             the
             root
             .
             Some
             might
             think
             ,
             it
             ought
             not
             to
             fall
             directly
             above
             the
             place
             it
             hang
             over
             ,
             but
             rather
             some
             distance
             behind
             ,
             seing
             the
             Ship
             hath
             advanced
             so
             much
             bounds
             ,
             in
             the
             time
             ,
             wherein
             the
             stone
             is
             coming
             down
             .
             Likewise
             ,
             while
             a
             Ship
             is
             under
             Sail
             ,
             let
             a
             man
             throw
             up
             a
             stone
             never
             so
             high
             ,
             and
             never
             so
             perpendicular
             ,
             as
             to
             his
             apprehension
             ,
             yet
             it
             will
             fall
             down
             directly
             upon
             his
             head
             again
             ,
             notwithstanding
             that
             the
             Ship
             hath
             run
             (
             perhaps
             )
             her
             own
             length
             in
             the
             time
             ,
             while
             the
             stone
             was
             ascending
             and
             descending
             .
             This
             experiment
             I
             find
             to
             hold
             true
             ,
             which
             may
             be
             easily
             tryed
             ,
             especially
             when
             a
             man
             is
             carried
             in
             a
             Boat
             upon
             smooth
             Water
             ,
             drawn
             by
             a
             horse
             ,
             as
             is
             done
             in
             some
             places
             abroad
             .
             Let
             him
             therefore
             throw
             up
             a
             little
             Stone
             ,
             or
             any
             heavy
             Body
             ,
             and
             he
             will
             find
             it
             descend
             just
             upon
             his
             head
             ,
             notwithstanding
             that
             the
             Horse
             that
             draggs
             the
             Boat
             ,
             be
             under
             a
             gallop
             ,
             and
             by
             this
             means
             hath
             advanced
             ten
             or
             twelve
             paces
             in
             the
             time
             .
             Or
             while
             the
             Boat
             is
             thus
             running
             ,
             let
             a
             man
             throw
             a
             stone
             towards
             the
             brink
             of
             the
             VVater
             ;
             in
             this
             case
             he
             shall
             not
             hit
             the
             place
             he
             aimed
             at
             ,
             but
             some
             other
             place
             more
             forward
             .
             This
             lets
             us
             see
             ,
             that
             when
             a
             Gun
             is
             fired
             in
             a
             Ship
             under
             Sail
             ,
             the
             Bullet
             cannot
             hit
             the
             place
             it
             was
             directed
             to
             .
             Neither
             can
             a
             man
             riding
             with
             a
             full
             Career
             ,
             and
             shooting
             a
             Pistol
             ,
             hit
             the
             person
             he
             aims
             at
             ,
             but
             must
             surely
             miss
             
             him
             ,
             notwithstanding
             ,
             that
             though
             in
             the
             very
             instant
             of
             time
             wherein
             he
             fires
             ,
             the
             mouth
             of
             the
             Pistol
             was
             most
             justly
             directed
             .
             For
             remedy
             whereof
             ,
             allowance
             must
             be
             granted
             in
             the
             aiming
             at
             the
             mark
             .
          
           
             VVhile
             a
             man
             throws
             up
             a
             stone
             in
             a
             Ship
             under
             Sail
             ,
             it
             must
             receive
             two
             distinct
             impulses
             ,
             one
             from
             the
             hand
             ,
             whereby
             it
             is
             carried
             upward
             ,
             the
             other
             from
             the
             Ship
             ,
             whereby
             it
             is
             carried
             forward
             .
             By
             this
             means
             ,
             the
             stone
             in
             going
             up
             ,
             and
             coming
             down
             ,
             cannot
             describe
             a
             perpendicular
             ,
             but
             a
             crooked
             Line
             ,
             either
             a
             Parabola
             ,
             or
             a
             Line
             very
             like
             unto
             it
             .
             Neither
             can
             it
             describe
             a
             perpendicular
             Line
             ,
             in
             coming
             down
             from
             the
             top
             of
             the
             Mast
             ,
             though
             in
             appearance
             it
             seem
             to
             do
             so
             ,
             but
             a
             crooked
             one
             ,
             which
             in
             effect
             must
             be
             the
             half
             of
             that
             ,
             which
             it
             describes
             in
             going
             up
             ,
             and
             coming
             down
             .
             For
             this
             same
             cause
             a
             stone
             thrown
             horizontally
             ,
             or
             towards
             the
             brink
             of
             the
             VVater
             ,
             must
             describe
             a
             crooked
             Line
             also
             .
             And
             a
             
               Pistol
               Bullet
            
             shot
             ,
             while
             a
             man
             is
             riding
             at
             a
             full
             Carreer
             ,
             must
             describe
             a
             Line
             of
             the
             same
             kind
             .
             Note
             ,
             that
             a
             man
             walking
             from
             the
             Stern
             of
             a
             Ship
             to
             the
             Head
             ,
             walks
             a
             longer
             way
             ,
             than
             in
             walking
             from
             the
             Head
             to
             the
             Stern
             .
             Secondly
             ,
             a
             man
             may
             walk
             from
             the
             Head
             to
             the
             Stern
             ,
             and
             yet
             not
             change
             his
             place
             .
             'T
             is
             observable
             ,
             that
             a
             man
             
               under
               board
            
             ,
             will
             not
             perceive
             whether
             the
             Ship
             be
             sailing
             ,
             or
             not
             ,
             and
             cannot
             know
             when
             her
             Head
             goes
             about
             .
             And
             it
             is
             strange
             ,
             that
             when
             a
             man
             is
             inclosed
             in
             a
             Hogs-head
             ,
             though
             he
             have
             light
             with
             him
             ,
             yet
             let
             him
             be
             never
             so
             oft
             whirled
             about
             ,
             he
             shall
             not
             know
             ,
             whether
             he
             be
             going
             about
             ,
             or
             not
             .
          
        
         
           
           
             OBSERVATION
             XIII
             .
          
           
             I
             Found
             in
             a
             
               Philosophical
               transaction
            
             lately
             Printed
             ,
             that
             Decemb.
             13.
             1669
             ,
             one
             
               Doctor
               Beal
            
             found
             the
             Mercury
             in
             the
             Baroscope
             ,
             never
             to
             be
             so
             high
             ,
             as
             it
             was
             then
             .
             That
             same
             very
             day
             ,
             I
             found
             the
             hight
             of
             it
             29
             inches
             ,
             and
             nine
             ten
             parts
             ,
             which
             I
             never
             observed
             before
             .
             And
             though
             the
             day
             here
             was
             dark
             ,
             and
             the
             Heavens
             covered
             with
             Clouds
             ,
             yet
             no
             rain
             for
             many
             dayes
             followed
             ,
             but
             much
             dryness
             ,
             and
             fair
             weather
             .
             On
             Saturday
             night
             ,
             March
             26
             ,
             1670
             ,
             I
             found
             the
             altitude
             no
             more
             than
             27
             ,
             and
             nine
             ten
             parts
             .
             This
             night
             was
             exceeding
             windy
             ,
             with
             a
             great
             rain
             .
             On
             February
             1
             ,
             1671.
             
             I
             found
             the
             altitude
             30
             inches
             ,
             and
             the
             Heavens
             most
             clear
             .
             But
             in
             the
             most
             part
             of
             May
             following
             ,
             I
             have
             found
             the
             hight
             but
             27
             inches
             ,
             and
             five
             ten
             parts
             ,
             in
             which
             time
             there
             was
             abundance
             of
             rain
             .
          
        
         
           
             OBSERVATION
             XIV
             .
          
           
             NOvember
             7.
             1670.
             
             I
             made
             exact
             trial
             ,
             with
             the
             
               Magnetick
               Needle
            
             for
             knowing
             the
             variation
             ,
             and
             I
             found
             it
             vary
             from
             the
             North
             ,
             three
             degrees
             and
             a
             half
             ,
             towards
             the
             West
             .
             Hevelius
             writes
             from
             Dantzick
             to
             the
             
               Royal
               Society
            
             at
             
               London
               ,
               Iuly
            
             5.
             1670
             ,
             that
             it
             varies
             with
             him
             seven
             degrees
             twenty
             minuts
             ,
             west
             .
          
        
         
           
             OBSERVATION
             XV.
             
          
           
             DEcember
             .
             17.
             1669
             ,
             I
             observed
             with
             a
             large
             Quadrant
             ,
             half
             9
             a
             clock
             at
             night
             ,
             the
             formost
             Guard-star
             ,
             when
             it
             was
             in
             the
             Meridian
             ,
             and
             lowest
             ,
             to
             have
             41
             degrees
             
             22
             minuts
             of
             altitude
             .
             And
             on
             Ianuary
             7.
             1670
             at
             7
             a
             clock
             in
             the
             morning
             ,
             I
             found
             it
             ,
             when
             it
             was
             in
             the
             Meridian
             ,
             and
             highest
             ,
             to
             have
             70
             degrees
             ,
             27
             minuts
             .
             Hence
             I
             conclude
             the
             
               elevation
               of
               the
               Pole
            
             here
             to
             be
             55
             degrees
             ,
             54
             minuts
             ,
             30
             seconds
             :
             and
             consequently
             as
             much
             at
             Edinburgh
             ;
             because
             both
             the
             places
             are
             upon
             one
             and
             the
             same
             Parallel
             .
          
        
         
           
             OBSERVATION
             XVI
             .
          
           
             FOr
             finding
             the
             true
             Meridian
             ,
             follow
             this
             method
             .
             In
             some
             convenient
             place
             fix
             two
             Wyre
             strings
             with
             weights
             at
             them
             ,
             that
             they
             may
             hang
             perpendicular
             .
             Then
             in
             the
             night
             time
             ,
             observe
             ,
             when
             the
             
               fourth
               star
               of
               the
               Plough
            
             begins
             to
             come
             near
             to
             the
             lowest
             part
             of
             the
             Meridian
             ,
             at
             which
             time
             you
             will
             find
             the
             
               Polar
               star
            
             highest
             .
             Then
             ,
             so
             order
             the
             two
             strings
             ,
             by
             moving
             them
             hither
             ,
             and
             thither
             ,
             till
             both
             of
             them
             cover
             both
             the
             said
             Stars
             ,
             then
             shall
             they
             in
             that
             position
             give
             you
             the
             true
             South
             and
             North.
             This
             observation
             is
             the
             product
             of
             the
             seventh
             .
          
        
         
           
             OBSERVATION
             XVII
             .
          
           
             THere
             fell
             out
             in
             Mid
             and
             East-Lothian
             ,
             on
             
               Thursday
               May
            
             11
             ,
             1671
             ,
             in
             the
             afternoon
             ,
             a
             considerable
             shour
             of
             hail
             ,
             with
             thunder
             and
             rain
             .
             It
             came
             from
             the
             South-west
             ,
             with
             a
             great
             blast
             of
             wind
             ,
             and
             ran
             alongs
             from
             Picts-land-hills
             North-east
             ,
             towards
             the
             Sea
             coast
             .
             The
             hail
             were
             big
             in
             several
             places
             ,
             as
             
               Musquet
               Ball
            
             ,
             and
             many
             of
             them
             rather
             oval
             than
             round
             .
             Some
             persons
             suffered
             great
             loss
             of
             their
             
               young
               Pease
            
             ;
             others
             of
             their
             
               Glass
               Windows
            
             .
             Eight
             or
             ten
             days
             before
             ,
             there
             was
             a
             considerable
             heat
             ,
             
             and
             dry
             VVeather
             .
             For
             20
             dayes
             after
             ,
             cold
             Easterly
             winds
             ,
             with
             rain
             every
             day
             ,
             but
             especially
             ,
             in
             the
             end
             of
             the
             Moneth
             ,
             extraordinary
             rain
             and
             mist.
             This
             is
             so
             much
             the
             more
             to
             be
             observed
             ,
             because
             in
             this
             Countrey
             ,
             seldom
             such
             extraordinary
             hail
             falls
             out
             .
             This
             year
             the
             Agues
             and
             
               Trembling
               Fevers
            
             have
             been
             most
             frequent
             ,
             and
             to
             many
             deadly
             .
          
        
         
           
             OBSERVATION
             XVIII
             .
          
           
             I
             Did
             hear
             lately
             of
             a
             curious
             Experiment
             in
             Germany
             ,
             made
             by
             a
             Person
             of
             note
             ,
             which
             I
             shall
             briefly
             in
             this
             Observation
             ,
             let
             the
             Reader
             understand
             .
             And
             though
             I
             have
             heard
             since
             ,
             that
             it
             is
             now
             published
             in
             Print
             ,
             yet
             I
             hope
             it
             will
             not
             be
             impertinent
             to
             mention
             it
             here
             ,
             especially
             for
             their
             cause
             ,
             who
             cannot
             conveniently
             come
             to
             the
             knowledge
             of
             such
             things
             .
             And
             for
             this
             reason
             also
             ,
             that
             I
             may
             explicat
             the
             Phenomena
             thereof
             ,
             from
             the
             foregoing
             doctrine
             ,
             and
             demonstrat
             particularly
             the
             true
             cause
             of
             that
             admirable
             effect
             ,
             that
             's
             seen
             in
             it
             ,
             which
             I
             desiderat
             in
             the
             publisher
             .
             The
             Auctor
             then
             takes
             two
             Vessels
             of
             Brass
             ,
             each
             one
             of
             them
             in
             form
             of
             half
             a
             sphere
             ,
             of
             a
             pretty
             large
             size
             .
             Nothing
             can
             more
             fitly
             represent
             them
             for
             form
             and
             quantity
             ,
             than
             two
             Bee-skeps
             .
             Only
             ,
             each
             of
             them
             ,
             hath
             a
             strong
             Ring
             of
             Brass
             upon
             the
             Center
             without
             :
             and
             they
             are
             so
             contrived
             by
             the
             Artist
             ,
             that
             their
             orifices
             agree
             most
             exactly
             ,
             so
             that
             when
             they
             are
             united
             ,
             they
             represent
             an
             intire
             Sphere
             almost
             .
             In
             one
             of
             the
             sides
             ,
             there
             's
             a
             hole
             ,
             and
             a
             
               Brass
               Spigot
            
             in
             it
             ,
             through
             which
             the
             whole
             Air
             within
             ,
             is
             exsucted
             ,
             and
             drawn
             out
             ,
             namely
             by
             the
             help
             of
             the
             Air-pump
             .
             And
             ,
             when
             by
             several
             exsuctions
             the
             Vessels
             are
             made
             empty
             ,
             the
             Stop-cock
             is
             turned
             
             about
             ,
             by
             which
             means
             ,
             no
             Air
             can
             come
             in
             .
             And
             ,
             they
             remaining
             empty
             ,
             are
             taken
             from
             the
             Pump
             ,
             and
             do
             cleave
             so
             fast
             together
             ,
             that
             though
             a
             number
             of
             
               lusty
               fellows
            
             ,
             12
             on
             each
             side
             ,
             do
             pull
             vigorously
             ,
             by
             help
             of
             ropes
             fastned
             to
             the
             Rings
             ,
             yet
             are
             they
             not
             able
             to
             pull
             them
             asunder
             .
             And
             because
             this
             will
             not
             do
             it
             ,
             he
             yokes
             in
             12
             
               Coach
               Horses
            
             ,
             six
             on
             every
             side
             ,
             yet
             are
             they
             not
             sufficient
             ,
             though
             they
             pull
             contrariwise
             to
             other
             ,
             to
             make
             a
             separation
             .
             But
             to
             let
             the
             Spectators
             see
             ,
             that
             they
             may
             be
             pulled
             asunder
             ,
             he
             yokes
             in
             9
             or
             10
             on
             every
             side
             ,
             and
             then
             after
             much
             whipping
             ,
             and
             sweating
             ,
             they
             pull
             the
             one
             from
             the
             other
             .
          
           
             The
             cause
             of
             this
             admirable
             effect
             ,
             is
             not
             the
             fear
             of
             vacuity
             ,
             as
             some
             do
             fancy
             ,
             for
             if
             that
             were
             ,
             all
             the
             Horses
             in
             Germany
             would
             not
             pull
             them
             asunder
             ,
             no
             not
             the
             strength
             of
             Angels
             .
             It
             must
             then
             be
             some
             extrinsick
             weight
             and
             force
             ,
             that
             keeps
             them
             together
             ,
             which
             can
             be
             nothing
             else
             ,
             but
             the
             weight
             of
             the
             
               invironing
               Air.
            
             Because
             ,
             no
             sooner
             a
             force
             is
             applied
             ,
             that
             's
             more
             powerful
             ,
             than
             the
             weight
             of
             the
             Air
             ,
             but
             assoon
             they
             come
             asunder
             .
             And
             so
             neither
             six
             men
             ,
             nor
             six
             horses
             on
             each
             side
             are
             able
             to
             do
             it
             :
             but
             nine
             or
             ten
             on
             each
             side
             makes
             a
             separation
             .
             For
             understanding
             the
             true
             cause
             of
             this
             Phenomenon
             ,
             we
             must
             consider
             that
             the
             Vessels
             are
             18
             inches
             in
             diameter
             .
             I●
             this
             be
             ,
             then
             according
             to
             the
             last
             Experiment
             ,
             there
             are
             two
             Pillars
             of
             Air
             ,
             each
             one
             of
             them
             as
             heavy
             as
             a
             Pillar
             of
             Mercury
             18
             inches
             thick
             ,
             and
             29
             inches
             long
             ,
             by
             which
             they
             are
             united
             .
             Or
             ,
             each
             Pillar
             of
             Air
             ,
             is
             as
             heavy
             ,
             as
             a
             Pillar
             0●
             Water
             34
             foot
             high
             ,
             and
             18
             inches
             in
             diameter
             .
             For
             finding
             the
             weight
             of
             it
             in
             pounds
             ,
             and
             consequently
             ,
             the
             weight
             of
             each
             Pillar
             of
             Air
             ,
             by
             which
             the
             two
             Vessels
             are
             united
             ,
             follow
             this
             method
             ▪
             First
             ,
             multiply
             9
             the
             semi-diameter
             
             of
             the
             Pillar
             ,
             by
             54
             the
             circumference
             ,
             and
             this
             gives
             you
             486
             ,
             the
             half
             whereof
             is
             the
             bounds
             of
             the
             Area
             ,
             namely
             243.
             
             And
             because
             34
             foot
             contains
             408
             inches
             ,
             I
             multiply
             408
             by
             243
             ,
             the
             product
             whereof
             is
             99144
             ;
             so
             many
             square
             inches
             are
             in
             a
             Pillar
             of
             Water
             34
             foot
             high
             ,
             and
             18
             inches
             thick
             .
             Now
             seing
             there
             are
             1728
             inches
             in
             a
             
               cubical
               foot
            
             ,
             I
             divide
             the
             number
             99144
             ,
             by
             this
             number
             ,
             and
             I
             find
             57
             square
             foot
             of
             Water
             ,
             and
             more
             .
             And
             because
             every
             square
             foot
             weighs
             56
             pound
             Trois
             ,
             I
             multiply
             56
             by
             the
             number
             57
             ,
             and
             the
             product
             is
             3192
             pound
             ,
             which
             is
             the
             just
             weight
             of
             a
             Pillar
             of
             Water
             34
             foot
             high
             ,
             and
             18
             inches
             in
             diameter
             ,
             and
             which
             is
             the
             just
             weight
             also
             of
             each
             Pillar
             of
             Air
             ,
             by
             which
             the
             two
             Vessels
             are
             kept
             together
             ,
             which
             will
             be
             more
             weight
             than
             
               seven
               Hogs-heads
               full
               of
               Water
            
             .
             This
             is
             easily
             known
             ;
             for
             seing
             a
             quart
             of
             our
             measure
             weighs
             seven
             pound
             ,
             (
             or
             to
             speak
             strictly
             six
             pound
             fourteen
             ounces
             ,
             seing
             the
             Standard-jug
             of
             Striviling
             contains
             three
             pound
             seven
             ounces
             of
             Water
             )
             a
             gallon
             must
             weigh
             28
             pound
             :
             but
             16
             times
             28
             ,
             is
             448.
             
             A
             Puncheon
             then
             full
             of
             Water
             ,
             weighs
             448
             pound
             .
             If
             then
             you
             divide
             3192
             by
             448
             ,
             you
             will
             find
             more
             than
             7.
             
             The
             9
             horses
             then
             upon
             this
             side
             have
             3192
             pound
             weight
             to
             draw
             ,
             or
             199
             stone
             ,
             or
             the
             weight
             of
             
               seven
               Hogs-heads
               full
               of
               Water
            
             .
             The
             other
             9
             horses
             upon
             the
             other
             side
             ,
             have
             as
             much
             to
             pull
             .
             'T
             is
             no
             wonder
             then
             to
             see
             so
             much
             difficulty
             and
             pains
             to
             make
             a
             separation
             .
             It
             is
             observed
             ,
             that
             before
             the
             Air
             be
             exsucted
             and
             drawn
             out
             of
             the
             two
             Vessels
             ,
             one
             man
             is
             able
             to
             pull
             them
             asunder
             with
             his
             hands
             only
             .
             Nay
             ,
             which
             is
             more
             ,
             if
             he
             but
             blow
             into
             them
             ,
             as
             a
             man
             doth
             into
             a
             Bladder
             ,
             he
             will
             separat
             them
             .
             The
             reason
             is
             ,
             because
             the
             Air
             within
             ,
             is
             of
             as
             great
             force
             ,
             as
             the
             Air
             without
             .
             'T
             is
             observable
             next
             ,
             that
             the
             larger
             the
             Vessels
             be
             
             in
             diameter
             ,
             the
             more
             strength
             is
             required
             to
             pull
             the
             one
             from
             the
             other
             .
             Upon
             supposition
             then
             ,
             they
             were
             4
             foot
             wide
             ,
             I
             verily
             believe
             30
             yoke
             of
             oxen
             ,
             upon
             every
             side
             ,
             would
             hardly
             disjoyn
             them
             ;
             because
             the
             weight
             of
             each
             Pillar
             of
             Air
             ,
             would
             be
             no
             less
             ,
             than
             22844
             pound
             ,
             which
             would
             take
             63
             strong
             horses
             to
             overcome
             the
             force
             of
             it
             .
             To
             pull
             the
             one
             Vessel
             therefore
             from
             the
             other
             ,
             there
             must
             be
             126
             horses
             ,
             that
             is
             ,
             63
             on
             every
             side
             .
          
        
         
           
             OBSERVATION
             XIX
             .
          
           
             THough
             this
             Observation
             may
             seem
             useless
             ,
             because
             the
             Proposals
             ,
             that
             are
             mentioned
             in
             it
             ,
             cannot
             be
             made
             out
             ,
             and
             brought
             to
             pass
             ,
             the
             Author
             having
             died
             ,
             before
             he
             had
             encouragment
             to
             prosecute
             them
             :
             yet
             for
             these
             following
             reasons
             ,
             I
             have
             adventured
             to
             insert
             it
             here
             .
             First
             ,
             that
             others
             ,
             may
             either
             be
             minded
             to
             find
             out
             (
             if
             possible
             )
             his
             inventions
             ,
             or
             set
             a
             work
             to
             find
             out
             somethings
             ,
             that
             may
             be
             as
             useful
             .
             Next
             ,
             because
             ,
             he
             was
             one
             of
             this
             same
             Nation
             ,
             and
             a
             great
             Master
             of
             the
             Mathematicks
             ,
             not
             only
             in
             the
             Speculative
             ,
             but
             in
             the
             Practical
             part
             chiefly
             ,
             and
             admirable
             for
             invention
             .
             And
             for
             this
             cause
             principally
             I
             have
             presumed
             to
             mention
             his
             designs
             ,
             and
             proposals
             ,
             which
             were
             found
             among
             his
             Notes
             ,
             after
             his
             death
             ,
             which
             are
             here
             insert
             ,
             as
             they
             were
             written
             with
             his
             own
             hand
             ,
             and
             offered
             to
             the
             publick
             ,
             not
             only
             at
             home
             ,
             but
             abroad
             to
             strangers
             .
             There
             have
             been
             men
             in
             all
             ages
             famous
             ,
             for
             some
             one
             Art
             and
             Science
             beyond
             others
             ,
             as
             Apelles
             for
             Painting
             ,
             Hippocrates
             for
             Medicine
             ,
             Demosthenes
             for
             Oratry
             ,
             but
             who
             have
             been
             more
             famous
             in
             their
             time
             than
             some
             persons
             for
             their
             profound
             knowledge
             in
             
               Astronomy
               ,
               Geometry
            
             ,
             and
             the
             other
             parts
             of
             the
             Mathematicks
             .
             What
             
             an
             admirable
             person
             was
             Archimedes
             for
             his
             divine
             knowledge
             ,
             both
             in
             the
             Speculative
             ,
             and
             Practical
             part
             .
             Yet
             ,
             it
             was
             not
             his
             speculations
             simply
             ,
             though
             excellent
             ,
             that
             did
             so
             much
             commend
             him
             ,
             as
             his
             Inventions
             ,
             and
             admirable
             Engines
             for
             peace
             and
             war
             ,
             as
             is
             clear
             from
             the
             
               Romane
               Histories
            
             ,
             and
             others
             .
             I
             confess
             the
             Students
             of
             these
             Arts
             ,
             are
             not
             so
             much
             in
             request
             now
             ,
             at
             least
             amongst
             some
             ,
             and
             that
             knowledge
             is
             not
             so
             much
             esteemed
             ;
             and
             the
             reason
             may
             be
             ;
             because
             some
             who
             profess
             themselves
             
               great
               Masters
            
             ,
             study
             nothing
             but
             the
             pure
             speculations
             ,
             which
             sometimes
             are
             to
             small
             purpose
             ,
             others
             before
             knowing
             the
             same
             ,
             unless
             for
             perfecting
             of
             the
             mind
             ,
             and
             giving
             to
             a
             man
             some
             private
             satisfaction
             .
             But
             such
             things
             will
             never
             commend
             a
             man
             so
             much
             as
             the
             practical
             part
             ,
             and
             new
             Invention
             will
             do
             .
             'T
             is
             surely
             a
             small
             business
             for
             one
             to
             do
             nothing
             ,
             but
             to
             nibble
             at
             some
             petty
             Demonstration
             .
             But
             when
             such
             speculations
             are
             joyned
             with
             invention
             and
             practice
             ,
             for
             the
             profit
             ,
             and
             use
             of
             men
             ,
             among
             whom
             they
             live
             ,
             then
             are
             they
             far
             more
             to
             be
             commended
             .
             And
             if
             this
             be
             not
             ,
             such
             knowledge
             is
             of
             small
             advantage
             to
             themselves
             or
             others
             .
             Many
             of
             the
             Ancient
             ,
             and
             late
             Astronomers
             have
             been
             ,
             and
             are
             famous
             for
             practice
             ,
             as
             witness
             the
             indefatigable
             pains
             they
             have
             been
             at
             in
             making
             their
             Observations
             .
             What
             hath
             so
             highly
             commended
             Merchiston
             over
             all
             Europe
             ,
             as
             his
             inventions
             ,
             especially
             his
             Logarithmes
             ?
             And
             if
             all
             be
             true
             ,
             that
             's
             reported
             (
             which
             I
             am
             apt
             to
             believe
             )
             he
             might
             have
             been
             more
             renowned
             ,
             for
             his
             many
             excellent
             Engines
             ,
             which
             though
             useful
             ,
             yet
             because
             hurtful
             to
             mankind
             ,
             he
             buried
             with
             himself
             .
             I
             am
             confident
             ,
             if
             the
             Author
             of
             these
             proposals
             had
             had
             time
             to
             have
             prosecuted
             them
             ,
             he
             would
             have
             been
             celebrated
             in
             the
             Catalogue
             of
             the
             most
             famous
             Mathematicians
             of
             his
             time
             .
             But
             leaving
             this
             ,
             I
             
             shall
             give
             you
             them
             in
             his
             own
             words
             :
             but
             first
             his
             Apology
             .
          
           
             These
             bold
             proposals
             will
             need
             perhaps
             an
             apology
             to
             such
             ,
             to
             whom
             the
             causes
             ,
             and
             circumstances
             are
             unknown
             .
             Let
             it
             suffice
             ,
             that
             the
             Proposer
             finding
             himself
             between
             two
             extreams
             ,
             either
             to
             leave
             unprosecuted
             this
             affair
             ,
             for
             fear
             of
             being
             mistaken
             by
             some
             ,
             as
             impudent
             ,
             or
             to
             commit
             himself
             openly
             to
             the
             charitable
             judgement
             of
             others
             ,
             who
             will
             suspend
             their
             censure
             ,
             till
             they
             have
             seen
             what
             his
             endeavours
             will
             produce
             .
             He
             hath
             rather
             chosen
             this
             last
             ,
             especially
             considering
             ,
             that
             his
             silence
             could
             not
             answer
             to
             his
             duty
             ,
             which
             he
             owes
             to
             his
             Countreys
             service
             ,
             seing
             the
             following
             Engines
             may
             be
             so
             useful
             to
             it
             .
             A
             deduction
             of
             the
             fabrick
             ,
             causes
             ,
             and
             occasions
             of
             these
             
               new
               Engines
            
             ,
             that
             set
             the
             Inventer
             a-work
             ,
             would
             take
             a
             long
             time
             to
             discourse
             upon
             .
             This
             Paper
             therefore
             is
             only
             destined
             for
             a
             short
             information
             of
             their
             use
             ,
             the
             rest
             ,
             which
             could
             not
             here
             be
             insert
             without
             impertinency
             ,
             may
             be
             supplied
             afterwards
             (
             if
             need
             be
             )
             either
             by
             a
             discourse
             ,
             or
             by
             a
             particular
             demonstration
             .
             The
             Proposer
             then
             is
             of
             opinion
             ,
             (
             if
             self-love
             of
             his
             own
             Inventions
             do
             not
             blind
             his
             Judgement
             )
             that
             these
             paradoxes
             may
             be
             truly
             affirmed
             .
          
           
             That
             if
             it
             shall
             please
             His
             Majesty
             to
             arm
             with
             these
             new
             Arms
             ,
             and
             Engines
             ,
             500
             Foot
             ,
             or
             fewer
             ,
             this
             small
             number
             shall
             be
             Masters
             of
             the
             Fields
             in
             
               France
               ,
               Germany
               ,
               Spain
            
             ,
             or
             where
             else
             it
             shall
             please
             His
             Majesty
             ,
             however
             encountered
             by
             the
             most
             powerful
             Army
             of
             Horse
             or
             Foot
             ,
             armed
             with
             ordinary
             Arms
             ,
             of
             Pistol
             ,
             Carabine
             ,
             Pike
             ,
             Musquet
             ,
             which
             Europe
             can
             bring
             to
             the
             Fields
             .
          
           
             The
             cause
             of
             this
             admirable
             effect
             ,
             is
             in
             the
             quality
             of
             these
             new
             Arms
             ,
             by
             which
             ,
             the
             whole
             Horsemen
             and
             Footmen
             of
             the
             enemy
             are
             rendred
             useless
             ,
             and
             unservicable
             ;
             
             neither
             can
             they
             do
             any
             offence
             to
             these
             ,
             who
             are
             so
             armed
             .
          
           
             The
             Musquetteers
             ,
             who
             can
             only
             serve
             against
             these
             Machins
             ,
             shall
             be
             put
             to
             such
             disadvantage
             ,
             as
             it
             is
             impossible
             they
             can
             stand
             ,
             the
             least
             time
             ,
             in
             the
             common
             way
             of
             service
             with
             the
             Musquet
             ,
             it
             not
             being
             able
             to
             make
             one
             shot
             for
             twenty
             ,
             which
             shall
             be
             made
             from
             these
             new
             Engines
             .
          
           
             These
             
               new
               Arms
            
             ,
             have
             this
             advantage
             likewise
             ,
             that
             these
             who
             are
             so
             armed
             ,
             can
             by
             no
             force
             of
             Horse
             or
             Foot
             be
             broken
             ,
             or
             put
             to
             disorder
             .
             The
             Souldiers
             are
             also
             by
             them
             put
             to
             a
             necessity
             of
             keeping
             together
             ,
             and
             fighting
             ,
             and
             by
             them
             ,
             they
             are
             so
             Baricado'd
             ,
             and
             strongly
             defended
             ,
             that
             if
             they
             leave
             them
             not
             ,
             they
             cannot
             be
             exposed
             to
             danger
             .
             This
             contributes
             much
             to
             good
             Discipline
             ,
             when
             the
             Souldiers
             shall
             by
             necessity
             be
             tied
             to
             his
             duty
             ,
             and
             fear
             ,
             which
             otherwise
             makes
             him
             run
             away
             ,
             shall
             here
             for
             his
             safety
             make
             him
             stand
             .
          
           
             These
             
               new
               Arms
            
             are
             useful
             ,
             as
             well
             in
             Marching
             ,
             as
             in
             Combating
             ,
             for
             with
             them
             ,
             we
             may
             march
             securely
             two
             in
             front
             ,
             through
             the
             straitest
             passages
             ,
             and
             be
             able
             to
             force
             with
             them
             any
             advantage
             a
             strait
             passage
             can
             give
             to
             an
             enemy
             .
             Besides
             ,
             for
             a
             long
             hasty
             march
             ,
             where
             Victuals
             cannot
             be
             well
             carried
             ,
             the
             Souldiers
             are
             able
             with
             these
             Arms
             to
             carry
             their
             own
             provision
             for
             eight
             dayes
             ,
             with
             more
             facility
             ,
             then
             they
             can
             now
             carry
             one
             dayes
             provision
             .
          
           
             To
             lodge
             in
             the
             open
             fields
             ,
             these
             Arms
             shall
             need
             no
             Intrenching
             ,
             for
             they
             sufficiently
             both
             Arm
             and
             Baricade
             the
             Souldiers
             .
          
           
             And
             as
             they
             are
             useful
             in
             Service
             ,
             so
             are
             they
             a
             great
             deal
             cheaper
             than
             the
             ordinary
             Arms.
             For
             although
             with
             5
             thousand
             men
             so
             armed
             ,
             the
             service
             of
             100000
             armed
             with
             common
             Arms
             may
             be
             done
             ,
             yet
             the
             whole
             price
             of
             
             them
             will
             not
             amount
             to
             that
             which
             will
             be
             required
             for
             arming
             20500
             Corrassiers
             ,
             as
             may
             be
             particularly
             deduced
             ,
             from
             the
             particular
             prices
             of
             the
             Arms
             ,
             and
             Engines
             fitted
             for
             the
             service
             of
             5000
             men
             .
             The
             Proposet
             doth
             offer
             to
             shew
             ,
             that
             these
             Arms
             will
             not
             surmount
             40000
             pound
             Sterling
             .
             The
             Artillery
             will
             amount
             to
             4500
             ,
             and
             the
             payments
             of
             this
             number
             of
             men
             so
             armed
             ,
             yearly
             to
             70000
             pound
             .
             Yet
             all
             these
             are
             taken
             in
             so
             large
             a
             latitude
             of
             reckoning
             ,
             as
             the
             sum
             of
             
               Arms
               ,
               Artillery
            
             ,
             and
             payments
             ,
             will
             not
             be
             much
             above
             130000
             pound
             Sterling
             .
          
           
             The
             Arms
             from
             which
             this
             effect
             is
             promised
             ,
             are
             
               new
               Engines
            
             ,
             with
             which
             one
             man
             is
             able
             to
             do
             the
             service
             of
             a
             great
             many
             Musquetteers
             .
             And
             those
             are
             of
             two
             sorts
             ,
             either
             to
             be
             used
             upon
             a
             small
             Wagon
             for
             Footmen
             ,
             or
             on
             a
             greater
             for
             a
             Horse
             ,
             with
             either
             of
             which
             ,
             one
             hand
             is
             able
             to
             make
             the
             fire
             of
             100
             Musquetteers
             ,
             and
             so
             much
             better
             ,
             by
             how
             much
             it
             is
             more
             regularly
             ,
             and
             fitly
             done
             for
             execution
             and
             offence
             .
             The
             new
             Cannon
             shall
             have
             the
             like
             advantage
             above
             the
             old
             ,
             both
             for
             easie
             carriage
             ,
             being
             lighter
             ,
             and
             for
             greater
             execution
             ,
             shooting
             six
             ,
             nine
             ,
             or
             twelve
             Bullets
             for
             one
             .
             These
             Arms
             give
             not
             only
             this
             advantage
             at
             Land
             in
             the
             field
             ,
             but
             also
             in
             Ships
             ,
             and
             places
             of
             defence
             .
          
           
             These
             nine
             following
             propositions
             he
             likewise
             offered
             to
             make
             good
             ,
          
           
             First
             ,
             With
             one
             shot
             of
             Cannon
             ,
             to
             do
             the
             execution
             of
             five
             shot
             of
             the
             same
             Cannon
             ,
             in
             the
             common
             way
             of
             Battery
             .
          
           
             Secondly
             ,
             to
             disable
             any
             Ship
             or
             Galley
             with
             one
             shot
             of
             Cannon
             .
          
           
             Thirdly
             ,
             to
             fire
             any
             combustible
             matter
             with
             the
             shot
             of
             a
             Cannon
             .
          
           
           
             Fourthly
             ,
             to
             make
             an
             Machin
             or
             Engine
             for
             transporting
             an
             Army
             ,
             which
             may
             be
             carried
             without
             the
             incommodity
             thereof
             .
          
           
             Fifthly
             ,
             to
             make
             a
             flotting
             Fortress
             for
             defence
             of
             Rivers
             ,
             and
             prohibition
             of
             Passages
             .
          
           
             Sixthly
             ,
             to
             make
             a
             Mortar
             that
             hath
             a
             
               directory
               Stell
            
             upon
             the
             Carriage
             .
          
           
             Seventhly
             ,
             to
             make
             Petards
             of
             divers
             forms
             ,
             that
             shall
             be
             able
             to
             do
             twice
             as
             much
             execution
             ,
             as
             those
             that
             contain
             as
             much
             Powder
             .
          
           
             Eighthly
             ,
             to
             make
             small
             Petards
             of
             great
             effect
             .
          
           
             Lastly
             ,
             to
             make
             Bridges
             ,
             and
             
               Scaling
               Ladders
            
             of
             easie
             Carriage
             .
          
        
         
           
             OBSERVATION
             XX
             :
          
           
             THese
             Observations
             being
             Miscellany
             ,
             require
             not
             a
             formal
             connexion
             between
             themselves
             ,
             and
             therefore
             't
             is
             no
             matter
             what
             method
             I
             keep
             in
             setting
             them
             down
             .
             And
             though
             this
             may
             seem
             not
             so
             pertinent
             ,
             as
             others
             ,
             yet
             because
             the
             design
             of
             it
             is
             only
             Philosophical
             ,
             and
             for
             advancing
             the
             Historical
             part
             of
             Learning
             in
             order
             to
             Spirits
             ,
             upon
             which
             the
             Scientifical
             part
             doth
             so
             much
             depend
             ,
             I
             have
             presumed
             to
             insert
             it
             here
             ,
             considering
             also
             that
             there
             are
             some
             ,
             who
             have
             adventured
             to
             deny
             their
             existence
             .
             and
             being
             ;
             which
             from
             such
             a
             History
             as
             this
             ,
             may
             be
             more
             than
             probably
             evicted
             .
             I
             find
             likewise
             ,
             that
             several
             Writers
             have
             remarked
             such
             strange
             accidents
             ,
             and
             have
             transmitted
             them
             to
             posterity
             ,
             which
             may
             serve
             for
             good
             use
             .
             The
             subject-matter
             then
             of
             this
             Observation
             ,
             is
             a
             true
             and
             short
             account
             of
             a
             remarkable
             trial
             ,
             wherewith
             the
             Family
             of
             one
             
               Gilbert
               Compbel
            
             ,
             by
             Profession
             a
             Weaver
             
             in
             the
             old
             Paroch
             of
             Glenl●●e
             in
             Galloway
             ,
             was
             exercised
             .
             Though
             the
             matter
             be
             well
             known
             to
             several
             persons
             at
             that
             time
             ,
             and
             since
             too
             ;
             yet
             there
             are
             others
             ,
             eighteen
             years
             interveening
             ,
             to
             whom
             (
             perhaps
             )
             such
             a
             relation
             will
             not
             be
             unacceptable
             ,
             who
             have
             either
             not
             as
             yet
             heard
             of
             it
             ,
             or
             at
             least
             ,
             have
             not
             gotten
             the
             true
             information
             ,
             which
             is
             here
             set
             down
             ,
             as
             it
             was
             Written
             ,
             at
             the
             desire
             of
             a
             special
             Friend
             ,
             by
             Gilbert
             Campbel's
             own
             Son
             ,
             who
             knew
             exactly
             the
             matter
             ,
             and
             all
             the
             circumstances
             ,
             whose
             words
             are
             as
             follows
             .
          
           
             It
             happened
             in
             October
             1654
             ,
             that
             after
             one
             
               Alexander
               Agnew
            
             ,
             a
             bold
             and
             sturdy
             Beggar
             ,
             who
             afterwards
             was
             hanged
             at
             Dumfreis
             for
             blasphemy
             ,
             had
             threatned
             hurt
             to
             the
             Family
             ,
             because
             he
             had
             not
             gotten
             such
             an
             alms
             as
             he
             required
             :
             the
             said
             Gilbert
             was
             oftentimes
             hindered
             in
             the
             exercise
             of
             his
             Calling
             ,
             all
             his
             Working-Instruments
             being
             some
             of
             them
             broken
             ,
             some
             of
             them
             cutted
             ,
             and
             yet
             could
             not
             know
             by
             what
             means
             this
             hurt
             was
             done
             ;
             which
             piece
             of
             trouble
             did
             continue
             ,
             till
             about
             the
             middle
             of
             November
             ,
             at
             which
             time
             the
             Devil
             came
             with
             new
             and
             extraordinary
             assaults
             ,
             by
             throwing
             of
             Stones
             in
             at
             Doors
             and
             Windows
             ,
             and
             down
             thorow
             the
             Chimney-head
             ,
             which
             were
             of
             great
             quantity
             ,
             and
             thrown
             with
             great
             force
             ,
             yet
             by
             Gods
             good
             providence
             ,
             there
             was
             not
             one
             person
             of
             the
             Family
             hurt
             ,
             or
             suffered
             damage
             thereby
             .
             This
             piece
             of
             new
             and
             sore
             trouble
             ,
             did
             necessitat
             Mr.
             Campbel
             to
             reveal
             that
             to
             the
             Minister
             of
             the
             Paroch
             ,
             and
             to
             some
             other
             Neighbours
             and
             Friends
             ,
             which
             hitherto
             he
             had
             endured
             secretly
             .
             Yet
             notwithstanding
             of
             this
             ,
             his
             trouble
             was
             enlarged
             ;
             for
             not
             long
             after
             ,
             he
             found
             oftentimes
             his
             Warp
             and
             Threeds
             cut
             ,
             as
             with
             a
             pair
             of
             Sizzers
             ,
             and
             the
             Reed
             broken
             :
             and
             not
             only
             this
             ,
             but
             their
             apparel
             cut
             after
             
             the
             same
             manner
             ,
             even
             while
             they
             were
             wearing
             them
             ,
             their
             Coats
             ,
             Bonnets
             ,
             Hose
             ,
             Shooes
             ,
             but
             could
             not
             discern
             how
             ,
             or
             by
             what
             mean.
             Only
             it
             pleased
             God
             to
             preserve
             their
             persons
             ,
             that
             the
             least
             harm
             was
             not
             done
             .
             Yet
             ,
             in
             the
             night
             time
             ,
             they
             wanted
             liberty
             to
             sleep
             ,
             something
             coming
             ,
             and
             pulling
             their
             Bed-cloaths
             and
             Linnings
             off
             them
             ,
             and
             leaving
             their
             bodies
             naked
             .
             Next
             ,
             their
             Chests
             ,
             and
             Trunks
             were
             opened
             ,
             and
             all
             things
             in
             them
             strawed
             here
             and
             there
             .
             Likewise
             ,
             the
             parts
             of
             the
             Working
             Instruments
             ,
             that
             had
             escaped
             ,
             were
             carried
             away
             ,
             and
             hid
             in
             holes
             and
             bores
             of
             the
             house
             ,
             where
             hardly
             they
             could
             be
             found
             again
             .
             Nay
             ,
             what-ever
             piece
             of
             Cloath
             ,
             or
             Houshold-stuff
             ,
             was
             in
             any
             part
             of
             the
             house
             ,
             it
             was
             carried
             away
             ,
             and
             so
             cut
             and
             abused
             ,
             that
             the
             Good-man
             was
             necessitated
             with
             all
             haste
             and
             speed
             ,
             to
             remove
             ,
             and
             to
             transport
             the
             rest
             to
             a
             Neighbours
             house
             ,
             and
             he
             himself
             compelled
             to
             quite
             the
             exercise
             of
             his
             Calling
             ,
             whereby
             only
             he
             maintained
             his
             Family
             .
             Yet
             ,
             he
             resolved
             to
             remain
             in
             the
             house
             for
             a
             season
             .
             During
             which
             time
             ,
             some
             persons
             about
             ,
             not
             very
             judicious
             ,
             counselled
             him
             to
             send
             his
             children
             out
             of
             the
             Family
             ,
             here
             and
             there
             ,
             to
             try
             whom
             the
             trouble
             did
             most
             follow
             ,
             assuring
             him
             ,
             that
             this
             trouble
             was
             not
             against
             all
             the
             Family
             ,
             but
             against
             some
             one
             person
             ,
             or
             other
             in
             it
             ,
             whom
             he
             too
             willingly
             obeyed
             .
             Yet
             ,
             for
             the
             space
             of
             four
             or
             five
             dayes
             after
             ,
             there
             were
             no
             remarkable
             assaults
             ,
             as
             before
             .
             The
             Minister
             hearing
             thereof
             ,
             shewed
             him
             the
             evil
             of
             such
             a
             course
             ,
             and
             assured
             him
             ,
             that
             if
             he
             repented
             not
             ,
             and
             called
             back
             his
             children
             ,
             he
             might
             not
             expect
             that
             his
             trouble
             would
             end
             in
             a
             right
             way
             .
             The
             children
             that
             were
             nigh
             by
             ,
             being
             called
             home
             ,
             no
             trouble
             followed
             ,
             till
             one
             of
             his
             sons
             ,
             called
             Thomas
             ,
             that
             was
             farrest
             off
             ,
             came
             home
             .
             Then
             did
             the
             Devil
             begin
             afresh
             ;
             
             for
             upon
             the
             
               Lords
               Day
            
             following
             ,
             in
             the
             afternoon
             ,
             the
             house
             was
             set
             on
             fire
             ,
             but
             by
             his
             providence
             ,
             and
             the
             help
             of
             some
             people
             ,
             going
             home
             from
             Sermon
             ,
             the
             fire
             was
             extinguished
             ,
             and
             the
             house
             saved
             ,
             not
             much
             loss
             being
             done
             .
             And
             the
             Monday
             after
             ,
             being
             spent
             in
             privat
             Prayer
             and
             Fasting
             ,
             the
             house
             was
             again
             set
             on
             fire
             upon
             the
             Tuesday
             about
             nine
             a
             Clock
             in
             the
             morning
             ,
             yet
             by
             providence
             ,
             and
             the
             help
             of
             Neighbours
             ,
             it
             was
             saved
             ,
             before
             any
             harm
             was
             done
             .
          
           
             Mr.
             Campbel
             ,
             being
             thus
             wearied
             ,
             and
             vexed
             ,
             both
             in
             the
             day
             ,
             and
             in
             the
             night
             time
             ,
             went
             to
             the
             Minister
             ,
             desiring
             him
             ,
             to
             let
             his
             son
             Thomas
             abide
             with
             him
             for
             a
             time
             ,
             who
             condescended
             ,
             but
             withal
             assured
             him
             ,
             that
             he
             would
             find
             himself
             deceived
             ,
             and
             so
             it
             came
             to
             pass
             :
             for
             ,
             notwithstanding
             that
             the
             child
             was
             without
             the
             family
             ,
             yet
             were
             they
             ,
             that
             remained
             in
             it
             ,
             fore
             troubled
             both
             in
             the
             day
             time
             ,
             and
             in
             the
             night
             season
             ,
             so
             that
             they
             were
             forced
             to
             wake
             till
             mid-night
             ,
             and
             sometimes
             all
             the
             night
             over
             .
             During
             which
             time
             ,
             the
             persons
             within
             the
             Family
             ,
             suffered
             many
             losses
             ,
             as
             the
             cutting
             of
             their
             Cloaths
             ,
             the
             throwing
             of
             Peits
             ,
             the
             pulling
             down
             of
             Tu●ff
             ,
             and
             Feal
             from
             the
             Roof
             ,
             and
             Walls
             of
             the
             House
             ,
             and
             the
             stealing
             of
             their
             Apparel
             ,
             and
             the
             pricking
             of
             their
             flesh
             and
             skin
             with
             Pins
             .
             The
             Presbytery
             having
             conveened
             at
             the
             place
             ,
             for
             a
             solemn
             Humiliation
             ,
             perswaded
             
               Gilbert
               Campbel
            
             to
             call
             back
             his
             Son
             Thomas
             ,
             notwithstanding
             of
             whatsoever
             hazard
             might
             follow
             .
             The
             Boy
             returning
             home
             ,
             affirmed
             that
             he
             heard
             a
             voice
             speak
             to
             him
             ,
             forbidding
             him
             to
             enter
             within
             the
             house
             ,
             or
             into
             any
             other
             place
             where
             his
             Fathers
             Calling
             was
             exercised
             .
             Yet
             he
             entered
             ,
             but
             was
             sore
             abused
             ,
             till
             he
             was
             forced
             to
             return
             to
             the
             Ministers
             house
             again
             .
          
           
             Upon
             Monday
             
               the
               12
               of
            
             February
             ,
             
               the
               rest
               of
               the
               Family
               
               began
               to
               hear
               a
               voice
               speak
               to
               them
               ,
               but
               could
               not
               well
               know
               from
               whence
               it
               came
               .
               Yet
               ,
               from
               evening
               till
               midnight
               ,
               too
               much
               vain
               discourse
               was
               kept
               up
               with
               the
            
             Devil
             ,
             
               and
               many
               idle
               and
               impertinent
               questions
               proposed
               ,
               without
               that
               due
               fear
               of
            
             God
             ,
             
               that
               should
               have
               been
               upon
               their
               Spirits
               ,
               under
               so
               rare
               and
               extraordinary
               a
               trial
               .
               The
            
             Minister
             
               hearing
               of
               this
               ,
               went
               to
               the
               house
               upon
               the
            
             Tuesday
             ,
             
               being
               accompanied
               with
               some
               Gentle-men
               ,
               who
               after
               Prayer
               was
               ended
               ,
               heard
               a
               voice
               speaking
               out
               of
               the
               ground
               ,
               from
               under
               a
               bed
               ,
               in
               the
               proper
               Countrey
               Dialect
               ,
               saying
               ,
            
             Would
             ye
             know
             the
             Witches
             of
             Glenluce
             ?
             I
             will
             tell
             you
             them
             ;
             
               and
               so
               related
               four
               or
               five
               persons
               names
               ,
               that
               went
               under
               an
               evil
               report
               .
               The
               said
            
             Gilbert
             
               informed
               the
               company
            
             ,
             That
             one
             of
             them
             was
             dead
             long
             ago
             .
             The
             Devil
             
               answered
               ,
               and
               said
            
             ,
             It
             is
             true
             ,
             she
             is
             dead
             long
             ago
             ,
             yet
             her
             spirit
             is
             living
             with
             us
             in
             the
             world
             .
             
               The
               Minister
               replied
               ,
               saying
               ,
               (
               though
               it
               was
               not
               convenient
               to
               speak
               to
               such
               a
               person
               )
            
             The
             Lord
             rebuke
             thee
             Satan
             ,
             and
             put
             thee
             to
             silence
             ;
             we
             are
             not
             to
             receive
             any
             information
             from
             thee
             ,
             whatsoever
             fame
             any
             persons
             go
             under
             .
             Thou
             art
             but
             seeking
             to
             seduce
             this
             Family
             :
             for
             Satans
             Kingdom
             is
             not
             divided
             against
             it self
             .
             
               After
               which
               all
               went
               to
               Prayer
               again
               ,
               which
               being
               ended
               (
               for
               during
               the
               time
               of
               Prayer
               no
               trouble
               was
               made
               )
               the
            
             Devil
             
               with
               many
               threatnings
               boasted
               and
               terrified
               the
               Lad
            
             Thomas
             ,
             
               who
               had
               come
               back
               that
               day
               with
               the
            
             Minister
             ,
             that
             if
             he
             did
             not
             depart
             out
             of
             the
             house
             ,
             he
             would
             set
             all
             on
             fire
             .
             The
             Minister
             
               answered
               ,
               and
               said
            
             ,
             The
             Lord
             will
             preserve
             the
             House
             ,
             and
             the
             Boy
             too
             ,
             seing
             he
             is
             one
             of
             the
             Family
             ,
             and
             hath
             Gods
             warrand
             to
             tarry
             in
             it
             .
             The
             Devil
             answered
             ,
             He
             shall
             not
             get
             liberty
             to
             stay
             :
             he
             was
             once
             put
             out
             already
             ,
             and
             shall
             not
             abide
             here
             ,
             though
             I
             should
             pursue
             him
             to
             the
             end
             of
             the
             world
             .
             The
             Minister
             replied
             ,
             The
             
             Lord
             will
             stop
             thy
             malice
             against
             him
             .
             
               And
               then
               they
               all
               prayed
               again
               ,
               which
               being
               ended
               ,
               the
            
             Devil
             said
             ,
             Give
             me
             a
             Spade
             and
             a
             Shovel
             ,
             and
             depart
             from
             the
             house
             for
             seven
             dayes
             ,
             and
             I
             shall
             make
             a
             grave
             ,
             and
             ly
             down
             in
             it
             ,
             and
             shall
             trouble
             you
             no
             more
             .
             The
             Good-man
             answered
             ,
             Not
             so
             much
             as
             a
             Straw
             shall
             be
             given
             thee
             ,
             through
             Gods
             assistance
             ,
             even
             though
             that
             would
             do
             it
             .
             The
             Minister
             
               also
               added
            
             ,
             God
             shall
             remove
             thee
             in
             due
             time
             .
             The
             Devil
             answered
             ,
             I
             will
             not
             remove
             for
             you
             ,
             I
             have
             my
             Commission
             from
             Christ
             to
             tarry
             ,
             and
             vex
             this
             Family
             .
             The
             Minister
             answered
             ,
             A
             permission
             thou
             hast
             indeed
             ,
             but
             God
             will
             stop
             it
             in
             due
             time
             .
             The
             Devil
             replied
             ,
             I
             have
             (
             Mes.
             Iohn
             )
             a
             Commission
             ,
             that
             (
             perhaps
             )
             will
             last
             longer
             than
             your
             own
             .
             
               After
               which
               ,
               the
            
             Minister
             
               and
               the
            
             Gentlemen
             
               arose
               ,
               and
               went
               to
               the
               place
               where
               the
               voice
               seemed
               to
               come
               from
               ,
               to
               try
               if
               they
               could
               find
               any
               thing
               .
               And
               after
               diligent
               search
               ,
               nothing
               being
               found
               ,
               the
            
             Gentlemen
             
               began
               to
               say
            
             ,
             We
             think
             this
             voice
             speaks
             out
             of
             the
             children
             ,
             
               for
               some
               of
               them
               were
               in
               their
               beds
               .
               The
            
             Devil
             answered
             ,
             You
             lie
             ,
             God
             shall
             judge
             you
             for
             your
             lying
             ,
             and
             I
             and
             my
             Father
             will
             come
             and
             fetch
             you
             to
             hell
             ,
             with
             
               Warlock-theeves
               ;
               and
               so
               the
            
             Devil
             
               discharged
               the
            
             Gentlemen
             
               to
               speak
               any
               ,
               saying
            
             ,
             Let
             him
             speak
             that
             hath
             a
             Commission
             (
             
               meaning
               the
            
             Minister
             )
             for
             he
             is
             the
             Servant
             of
             God.
             The
             Gentlemen
             
               returning
               back
               with
               the
            
             Minister
             ,
             
               they
               sat
               down
               near
               to
               the
               place
               whence
               the
               voice
               seemed
               to
               come
               from
               ,
               and
               he
               opening
               his
               mouth
               ,
               spake
               to
               them
               ,
               after
               this
               manner
               .
            
             The
             Lord
             will
             rebuke
             this
             Spirit
             ,
             in
             his
             own
             time
             ,
             and
             cast
             it
             out
             .
             The
             Devil
             
               answering
               ,
               said
            
             ,
             It
             is
             written
             in
             the
             9
             of
             Mark
             ,
             the
             Disciples
             could
             not
             cast
             him
             out
             .
             The
             Minister
             replied
             ,
             What
             the
             Disciples
             could
             not
             do
             ,
             yet
             the
             Lord
             having
             hightned
             the
             Parents
             faith
             ,
             for
             his
             own
             glory
             did
             cast
             him
             out
             ,
             and
             so
             shall
             
             he
             thee
             .
             The
             Devil
             replied
             ,
             It
             is
             written
             in
             the
             4
             of
             Luke
             ,
             And
             he
             departed
             ,
             and
             left
             him
             for
             a
             season
             .
             The
             Minister
             said
             ,
             The
             Lord
             in
             the
             dayes
             of
             his
             humiliation
             ,
             not
             only
             got
             the
             victory
             over
             Satan
             ,
             in
             that
             assault
             in
             the
             wilderness
             ,
             but
             when
             he
             came
             again
             ,
             his
             success
             was
             no
             better
             ,
             for
             it
             is
             written
             ,
             Joh.
             14.
             
             Behold
             the
             Prince
             of
             this
             world
             cometh
             ,
             and
             hath
             nothing
             in
             me
             ;
             and
             being
             now
             in
             glory
             ,
             he
             will
             fulfill
             his
             promise
             ,
             and
             God
             shall
             bruise
             Satan
             under
             your
             feet
             shortly
             ,
             
               Rom.
               16.
               
               The
            
             Devil
             answered
             ,
             It
             is
             written
             ,
             
               Mat.
               25.
            
             
             There
             were
             ten
             Virgins
             ,
             five
             wise
             ,
             and
             five
             foolish
             ;
             and
             the
             Bridegroom
             came
             :
             The
             foolish
             Virgins
             had
             no
             Oyl
             in
             their
             Lamps
             ,
             and
             they
             went
             unto
             the
             wise
             to
             seek
             Oyl
             ;
             and
             the
             wise
             said
             ,
             Go
             and
             buy
             for
             your selves
             :
             and
             while
             they
             went
             ,
             the
             Bridegroom
             came
             ,
             and
             entered
             in
             ,
             and
             the
             door
             was
             shut
             ,
             and
             the
             foolish
             Virgins
             were
             sent
             to
             hells
             fire
             .
             The
             Minister
             answered
             ,
             The
             Lord
             knows
             the
             sincerity
             of
             his
             servants
             ,
             and
             though
             there
             be
             sin
             and
             folly
             in
             us
             here
             ,
             yet
             there
             is
             a
             fountain
             opened
             to
             the
             house
             of
             David
             for
             sin
             and
             for
             uncleanness
             ,
             and
             when
             he
             hath
             washed
             us
             there
             ,
             and
             pardoned
             all
             our
             sins
             ,
             for
             his
             Names
             sake
             ,
             he
             will
             cast
             the
             unclean
             spirit
             out
             of
             the
             land
             .
             The
             Devil
             
               answered
               and
               said
            
             ,
             That
             place
             of
             Scripture
             is
             written
             in
             the
             13
             of
             Zechariah
             ,
             In
             that
             day
             I
             will
             cause
             the
             Prophets
             ,
             and
             the
             unclean
             spirit
             ,
             pass
             out
             of
             the
             land
             ;
             but
             afterwards
             it
             is
             written
             ,
             I
             will
             smite
             the
             Shepherd
             ,
             and
             the
             Sheep
             shall
             be
             scattered
             .
             The
             Minister
             
               answered
               and
               said
            
             ,
             Well
             are
             we
             ,
             that
             our
             blessed
             Shepherd
             was
             smitten
             ,
             and
             thereby
             hath
             bruised
             thy
             head
             ;
             and
             albeit
             in
             the
             hour
             of
             his
             sufferings
             ,
             his
             Disciples
             forsook
             him
             ,
             Mat.
             26.
             yet
             now
             having
             ascended
             on
             high
             ,
             he
             sits
             in
             glory
             ,
             and
             is
             preserving
             ,
             gathering
             in
             ,
             and
             turning
             his
             hand
             upon
             his
             little
             ones
             ,
             and
             will
             save
             his
             poor
             ones
             in
             this
             Family
             from
             thy
             malice
             .
             The
             Minister
             
               returning
               back
               a
               little
               ,
               and
               standing
               upon
               the
               floor
               ,
               
               the
            
             Devil
             said
             ,
             I
             knew
             not
             these
             Scriptures
             ,
             till
             my
             Father
             taught
             me
             them
             .
             I
             am
             an
             evil
             Spirit
             ,
             and
             Satan
             is
             my
             Father
             ,
             and
             I
             am
             come
             to
             vex
             this
             house
             ;
             
               and
               presently
               there
               appeared
               a
               naked
               hand
               ,
               and
               an
               arm
               ,
               from
               the
               elbow
               down
               ,
               beating
               upon
               the
               floor
               ,
               till
               the
               house
               did
               shake
               again
               ;
               and
               also
               the
            
             Devil
             
               uttered
               a
               most
               fearful
               and
               loud
               cry
               ,
               saying
               ,
            
             Come
             up
             Father
             ,
             come
             up
             :
             I
             will
             send
             my
             father
             among
             you
             .
             See
             ,
             there
             he
             is
             behind
             your
             backs
             .
             The
             Minister
             said
             ,
             I
             saw
             indeed
             an
             hand
             ,
             and
             an
             arm
             ,
             when
             the
             stroak
             was
             given
             ,
             and
             heard
             .
             The
             Devil
             
               said
               to
               him
            
             ,
             Saw
             you
             that
             ?
             It
             was
             not
             my
             hand
             ,
             it
             was
             my
             fathers
             ;
             my
             hand
             is
             more
             bl●ck
             in
             the
             loof
             .
             Would
             you
             see
             me
             ?
             Put
             out
             the
             candle
             then
             ,
             and
             I
             shall
             come
             butt
             the
             house
             among
             you
             like
             fire-balls
             .
             
               After
               which
               all
               went
               to
               Prayer
               ,
               during
               which
               time
               ,
               it
               did
               no
               harm
               ,
               neither
               at
               any
               other
               time
               when
            
             God
             
               was
               worshipped
               .
               When
               Prayer
               was
               ended
               ,
               the
            
             Devil
             
               answered
               and
               said
               ,
               Mes
               John
               ,
            
             if
             the
             Good-mans
             sons
             prayers
             at
             the
             Colledge
             of
             Glasgow
             ,
             did
             not
             prevail
             more
             with
             God
             ,
             than
             yours
             ,
             my
             father
             and
             I
             had
             wrought
             a
             mischief
             here
             ere
             now
             .
             
               To
               which
               one
               of
               the
               Gentlemen
               replied
               ,
               though
               a
               check
               had
               been
               given
               him
               before
               ,
            
             Well
             well
             ,
             I
             see
             you
             confess
             there
             is
             a
             God
             ,
             and
             that
             prayer
             prevails
             with
             him
             ,
             and
             therefore
             we
             must
             pray
             to
             God
             ,
             and
             will
             commit
             the
             event
             to
             him
             .
             
               To
               which
               the
            
             Devil
             replied
             ,
             Yea
             Sir
             ,
             you
             speak
             of
             prayer
             ,
             with
             your
             broad
             lipped
             Hat
             
               (
               for
               the
               Gentleman
               had
               lately
               gotten
               a
               new
               Hat
               in
               the
               fashion
               with
               broad
               lips
               )
            
             I
             'le
             bring
             a
             pair
             of
             Shears
             from
             my
             father
             ,
             that
             shall
             clip
             the
             lips
             of
             it
             a
             little
             .
          
           
             The
             night
             now
             being
             far
             spent
             ,
             it
             was
             thought
             fit
             every
             one
             should
             withdraw
             to
             his
             own
             home
             .
             Then
             did
             the
             Devil
             cry
             out
             fearfully
             ,
             
               Let
               not
               the
               Minister
               go
               home
               ,
               I
               shall
               burn
               the
               house
               if
               he
               go
            
             ;
             and
             many
             other
             wayes
             did
             he
             
             threaten
             .
             And
             after
             the
             Minister
             was
             gone
             forth
             ,
             the
             Good-man
             being
             instant
             with
             him
             to
             tarry
             ,
             whereupon
             he
             returned
             ,
             all
             the
             rest
             of
             the
             company
             going
             home
             .
             Then
             said
             the
             Devil
             to
             the
             
               Minister
               ,
               You
               have
               done
               my
               bidding
               .
               Not
               thine
               ,
            
             answered
             he
             ,
             
               but
               in
               obedience
               to
               God
               ,
               have
               I
               returned
               to
               bear
               this
               man
               company
               ,
               whom
               thou
               dost
               afflict
               .
            
             Then
             did
             the
             Minister
             call
             upon
             the
             Name
             of
             God
             ,
             and
             when
             Prayer
             was
             ended
             ,
             he
             discharged
             Mr.
             Campbel
             ,
             and
             all
             the
             persons
             of
             the
             Family
             ,
             from
             opening
             their
             mouth
             ,
             in
             one
             word
             to
             the
             
               evil
               spirit
            
             ,
             and
             when
             it
             spake
             ,
             that
             they
             should
             only
             kneel
             down
             ,
             and
             speak
             to
             God.
             The
             Devil
             then
             roared
             mightily
             ,
             and
             cryed
             out
             ,
             
               What
               ?
               Will
               ye
               not
               speak
               to
               me
               ?
               I
               shall
               burn
               the
               house
               ,
               I
               shall
               strike
               the
               bairns
               ,
               and
               do
               all
               manner
               of
               mischief
               .
            
             But
             after
             that
             time
             ,
             no
             answer
             was
             made
             to
             it
             ,
             and
             so
             for
             a
             long
             time
             no
             speech
             was
             heard
             .
             After
             this
             ,
             the
             said
             Gilbert
             suffered
             much
             loss
             ,
             and
             had
             many
             sad
             nights
             ,
             not
             two
             nights
             in
             one
             week
             free
             ;
             and
             thus
             it
             continued
             till
             April
             .
             From
             April
             to
             Iuly
             ,
             he
             had
             some
             respite
             ,
             and
             ease
             .
             But
             after
             ,
             he
             was
             molested
             with
             new
             assaults
             :
             and
             even
             their
             Victuals
             were
             so
             abused
             ,
             that
             the
             Family
             was
             in
             hazard
             of
             starving
             ;
             and
             that
             which
             they
             did
             eat
             ,
             gave
             them
             not
             the
             ordinary
             satisfaction
             they
             were
             wont
             to
             find
             .
          
           
             In
             this
             sore
             and
             sad
             affliction
             ,
             Mr.
             Campbel
             resolved
             to
             make
             his
             address
             to
             the
             Synod
             of
             Presbyters
             ,
             for
             advice
             and
             counsel
             what
             to
             do
             ,
             which
             was
             appointed
             to
             conveen
             in
             October
             1655
             ,
             namely
             whether
             to
             forsake
             the
             house
             and
             place
             ,
             or
             not
             ?
             The
             Synod
             by
             their
             Committee
             ,
             appointed
             to
             meet
             at
             Glenluce
             in
             Feb.
             1656
             ,
             thought
             fit
             ,
             that
             a
             solemn
             Humiliation
             should
             be
             kept
             thorow
             all
             the
             bounds
             of
             the
             Synod
             ,
             and
             amongst
             other
             causes
             ,
             to
             request
             God
             in
             behalf
             of
             that
             poor
             afflicted
             Family
             ,
             which
             being
             carefully
             
             done
             ,
             the
             event
             was
             ,
             through
             the
             Prayers
             of
             his
             People
             ,
             that
             his
             trouble
             grew
             less
             till
             April
             ,
             and
             from
             April
             to
             August
             ,
             he
             was
             altogether
             free
             .
             About
             which
             time
             ,
             the
             Devil
             began
             with
             new
             assaults
             ,
             and
             taking
             the
             ready
             meat
             that
             was
             in
             the
             house
             ,
             did
             sometimes
             hide
             it
             in
             holes
             by
             the
             door-posts
             ,
             and
             at
             other
             times
             did
             hide
             it
             under
             the
             beds
             ,
             and
             sometimes
             among
             the
             Bed-cloaths
             ,
             and
             under
             the
             Linnings
             ;
             and
             at
             last
             ,
             did
             carry
             it
             quite
             away
             ,
             till
             nothing
             was
             left
             there
             ,
             save
             Bread
             and
             Water
             to
             live
             by
             .
             After
             this
             ,
             he
             exercised
             his
             malice
             and
             cruelty
             against
             all
             the
             persons
             of
             the
             Family
             ,
             in
             wearying
             them
             in
             the
             night
             time
             ,
             with
             stirring
             and
             moving
             thorow
             the
             house
             ,
             so
             that
             they
             had
             no
             rest
             for
             noise
             ,
             which
             continued
             all
             the
             moneth
             of
             August
             after
             this
             manner
             .
             After
             which
             time
             ,
             the
             Devil
             grew
             yet
             worse
             ,
             and
             began
             with
             terrible
             roarings
             ,
             and
             terrifying
             voices
             ,
             so
             that
             no
             person
             could
             sleep
             in
             the
             house
             ,
             in
             the
             night
             time
             ,
             and
             sometimes
             did
             vex
             them
             with
             casting
             of
             stones
             ,
             striking
             them
             with
             staves
             on
             their
             beds
             in
             the
             night
             time
             :
             and
             upon
             the
             18
             of
             September
             ,
             about
             mid-night
             ,
             he
             cried
             out
             with
             a
             loud
             voice
             ,
             
               I
               shall
               burn
               the
               house
            
             ;
             and
             about
             three
             or
             four
             nights
             after
             ,
             he
             set
             one
             of
             the
             beds
             on
             fire
             ;
             which
             was
             soon
             extinguished
             ,
             without
             any
             prejudice
             ,
             except
             the
             bed
             it self
             :
             and
             so
             he
             continued
             to
             vex
             them
             .
          
        
         
           
           
             OBSERVATION
             XXI
             .
          
           
             I
             Need
             not
             make
             any
             apology
             for
             inserting
             this
             Observation
             ,
             even
             though
             it
             be
             well
             known
             upon
             the
             matter
             in
             this
             place
             .
             But
             because
             the
             thing
             is
             extraordinary
             ,
             and
             that
             there
             are
             many
             who
             have
             not
             so
             much
             as
             heard
             of
             it
             ,
             I
             have
             therefore
             presumed
             to
             mention
             it
             here
             .
             The
             matter
             is
             shortly
             this
             .
             There
             's
             a
             certain
             Woman
             ,
             named
             
               Mistri●
               Low
            
             ,
             who
             had
             a
             real
             and
             true
             Horn
             ,
             growing
             upon
             the
             right
             side
             of
             her
             Head
             ,
             three
             inches
             above
             her
             righ
             〈◊〉
             .
             The
             length
             of
             it
             is
             eleven
             inches
             ,
             and
             two
             inches
             about
             .
             The
             form
             is
             crooked
             spirally
             .
             It
             is
             convex
             on
             the
             outer
             side
             ,
             and
             somewhat
             guttered
             in
             the
             inner
             side
             .
             It
             is
             hard
             and
             solid
             ,
             and
             all
             very
             near
             of
             the
             same
             greatness
             .
             It
             is
             not
             hollow
             within
             ,
             as
             horns
             are
             ordinarily
             ,
             but
             full
             ,
             yet
             it
             seems
             to
             be
             spongious
             as
             a
             Cane
             is
             .
             It
             was
             seven
             years
             in
             growing
             ,
             and
             was
             cut
             off
             in
             May
             1671
             ,
             by
             
               Mr.
               Temple
            
             ,
             an
             expert
             Chirurgeon
             here
             at
             Edinburgh
             .
          
        
         
           
             OBSERVATION
             XXII
             .
          
           
             THis
             Observation
             is
             for
             finding
             the
             
               Primum
               vivens
            
             in
             Animals
             .
             Albeit
             I
             doubt
             not
             but
             the
             
               red
               Spirit
            
             ,
             or
             Blood
             ,
             in
             most
             
               Terrestrial
               Animals
            
             ,
             is
             the
             first
             product
             of
             the
             
               Primigenial
               juice
            
             ,
             and
             therefore
             not
             improperly
             named
             the
             true
             
               Callidum
               Innatum
            
             of
             these
             Creatures
             ,
             by
             the
             Noble
             and
             Ingenious
             Harvey
             ,
             in
             his
             Book
             
               de
               Generatione
            
             .
             Neither
             do
             I
             scruple
             to
             yeeld
             ,
             that
             the
             Heart
             ,
             and
             appendent
             Vessels
             ,
             are
             the
             first
             formed
             ,
             and
             perfected
             parts
             in
             the
             hotter
             kind
             of
             Animals
             :
             yet
             I
             am
             confident
             to
             affirm
             ,
             that
             in
             many
             of
             the
             colder
             ,
             and
             moifter
             kinds
             of
             Aquaticks
             ,
             if
             not
             in
             all
             ,
             neither
             the
             redness
             and
             heat
             of
             the
             
             
               Vital
               Spirits
            
             ,
             nor
             the
             formation
             of
             the
             
               Heart
               ,
               Liver
            
             ,
             &c.
             are
             previously
             requisite
             ,
             to
             the
             structure
             and
             existence
             of
             the
             other
             parts
             ;
             seing
             the
             light
             of
             life
             ,
             which
             at
             first
             inhabited
             the
             clear
             and
             Cristalin
             radical
             moisture
             ,
             before
             the
             formation
             of
             any
             particular
             part
             ,
             doth
             alwayes
             move
             in
             every
             living
             creature
             ,
             according
             to
             their
             particular
             exigency
             ,
             without
             any
             absolute
             dependency
             upon
             any
             one
             part
             ,
             or
             member
             (
             excepting
             singular
             conditions
             ,
             wherein
             they
             may
             be
             stated
             )
             as
             to
             its
             substance
             ,
             light
             ,
             and
             motion
             :
             there
             being
             in
             some
             Animals
             a
             simple
             undulation
             ,
             in
             others
             a
             slow
             creeping
             ,
             but
             in
             the
             more
             perfect
             ,
             an
             impetuous
             running
             ,
             or
             rather
             flying
             of
             the
             
               Vital
               Spirits
            
             ,
             necessarily
             required
             for
             illumination
             and
             vivification
             of
             the
             whole
             .
          
           
             For
             confirmation
             ,
             I
             shall
             give
             you
             this
             singular
             Experiment
             .
             About
             the
             middle
             of
             March
             ,
             the
             sperm
             of
             Frogs
             (
             according
             to
             the
             number
             of
             
               Prolifick
               Eggs
            
             therein
             contained
             )
             sends
             forth
             a
             multitude
             of
             small
             round
             Creatures
             ,
             covered
             with
             a
             black
             ,
             and
             moveable
             Frock
             ,
             which
             about
             the
             end
             of
             March
             ,
             and
             beginning
             of
             April
             ,
             by
             the
             Gyrations
             of
             a
             Tail
             behind
             ,
             like
             a
             Rudder
             ,
             do
             slowly
             move
             their
             bodies
             in
             the
             Water
             .
             At
             this
             time
             having
             opened
             severals
             of
             them
             ,
             I
             found
             nothing
             (
             apparent
             to
             the
             naked
             eye
             )
             but
             a
             clear
             thin
             Membran
             ,
             under
             the
             fore-named
             black
             Frock
             ,
             within
             which
             were
             contained
             a
             clear
             Water
             ,
             and
             some
             small
             Fibres
             like
             Intestines
             ,
             and
             in
             the
             fore-part
             a
             small
             orifice
             like
             a
             mouth
             .
             About
             the
             middle
             of
             April
             ,
             its
             motion
             is
             more
             vigorous
             ,
             and
             the
             Tripes
             within
             are
             most
             evident
             ,
             lying
             in
             a
             very
             fine
             circular
             order
             ,
             but
             as
             yet
             ,
             there
             is
             no
             Vestige
             of
             
               Heart
               ,
               Blood
            
             ,
             or
             Liver
             ,
             &c.
             
             About
             the
             middle
             of
             May
             ,
             the
             feet
             formed
             like
             small
             threeds
             ,
             appear
             thorow
             the
             black
             Coat
             :
             within
             the
             Breast
             ,
             the
             Heart
             is
             then
             visible
             ,
             of
             a
             white
             and
             Fibrous
             substance
             ,
             the
             Liver
             
             is
             white
             ,
             and
             the
             Gall
             therein
             easily
             discerned
             .
             But
             (
             which
             is
             the
             head
             of
             this
             Experiment
             )
             the
             Vital
             Spirit
             ,
             in
             form
             of
             a
             clear
             and
             pure
             Water
             ,
             is
             manifestly
             received
             by
             the
             Nervous
             Heart
             ,
             and
             by
             the
             contraction
             thereof
             transmitted
             to
             all
             the
             Body
             ,
             thorow
             white
             transparent
             Vessels
             ,
             which
             being
             full
             of
             this
             Liquor
             ,
             do
             represent
             the
             Lymphatick
             ,
             rather
             than
             the
             
               Sanguiferous
               Veins
            
             .
             Last
             of
             all
             do
             the
             
               Pneumatick
               Vesicles
            
             (
             which
             in
             this
             Amphibium
             supply
             the
             place
             of
             the
             Lungs
             )
             arise
             in
             the
             Breast
             ,
             after
             whose
             production
             ,
             the
             Lympid
             and
             Crystalin
             Liquor
             ,
             while
             the
             Heart
             is
             turgid
             therewith
             ,
             seems
             to
             be
             red
             and
             fiery
             ,
             but
             in
             the
             other
             Vessels
             ,
             it
             is
             of
             a
             faint
             pale
             colour
             ,
             untill
             (
             about
             ,
             or
             near
             the
             end
             of
             Iune
             )
             the
             Frock
             being
             cast
             off
             ,
             and
             a
             perfect
             Frog
             formed
             ,
             the
             whole
             Vessels
             are
             full
             of
             Blood
             ,
             or
             a
             red
             substance
             very
             thin
             ,
             and
             clear
             :
             the
             Liver
             ,
             and
             
               Pneumatick
               Vesicles
            
             ,
             &c.
             become
             red
             ,
             and
             Rosy
             ;
             so
             that
             the
             Blood
             in
             this
             Amphibium
             (
             which
             in
             the
             more
             perfect
             Animals
             is
             first
             compleat
             )
             seems
             to
             be
             the
             last
             part
             in
             attaining
             its
             perfection
             .
          
           
             That
             Salmonds
             ,
             and
             great
             Trouts
             have
             an
             aqueous
             liquor
             which
             runs
             thorow
             their
             Arteries
             ,
             and
             Veins
             ,
             before
             their
             Blood
             attain
             the
             true
             consistency
             ,
             and
             saturat
             tincture
             I
             am
             certain
             :
             whether
             it
             hold
             in
             many
             others
             ,
             I
             suspect
             ,
             but
             dar
             not
             affirm
             .
             Hence
             it
             may
             be
             (
             if
             mens
             observations
             ,
             were
             frequent
             in
             all
             kind
             of
             
               Anatomical
               inspections
            
             ,
             in
             several
             Embryo's
             of
             every
             species
             )
             it
             would
             be
             found
             evident
             ,
             that
             the
             Blood
             in
             all
             these
             ,
             called
             
               〈◊〉
               〈◊〉
               〈◊〉
               〈◊〉
               〈◊〉
            
             hath
             its
             immediat
             original
             from
             a
             simple
             homogeneous
             ,
             and
             uniform
             liquor
             ,
             and
             doth
             by
             gradual
             and
             frequent
             influences
             of
             the
             vital
             ferment
             of
             the
             heart
             ,
             receive
             at
             length
             the
             full
             tincture
             ,
             essence
             ,
             and
             subsistence
             requisite
             for
             vivification
             ,
             and
             illumination
             of
             the
             whole
             members
             .
          
           
           
             Whether
             this
             Experiment
             doth
             not
             sufficiently
             impugn
             the
             universality
             of
             the
             hearts
             first
             living
             ,
             the
             original
             of
             the
             Gall
             from
             the
             fervour
             ,
             and
             ebullition
             of
             the
             Blood
             ,
             the
             production
             of
             the
             Blood
             by
             the
             Liver
             ,
             and
             many
             other
             ancient
             errors
             ,
             let
             any
             judge
             ,
             who
             will
             but
             take
             pains
             to
             make
             and
             compare
             Harveys
             trials
             
               de
               ov●
            
             ,
             with
             this
             of
             the
             Porwigl
             or
             
               Gyrinus
               ,
               ab
               ovo
            
             .
          
           
             Yea
             ,
             if
             the
             aqueous
             liquor
             ,
             be
             not
             one
             with
             the
             vital
             Spirit
             ,
             and
             subsequent
             Blood
             ,
             then
             my
             eyes
             ,
             and
             taste
             are
             altogether
             erroneous
             .
          
           
             Moreover
             ,
             it
             were
             to
             be
             wished
             ,
             that
             Physitians
             would
             not
             simply
             stand
             upon
             the
             
               Galenick
               suppositions
            
             of
             the
             four
             alledged
             Components
             of
             the
             Blood
             ,
             nor
             any
             such
             ,
             or
             equivalent
             fancies
             of
             the
             latter
             Chymists
             ;
             but
             that
             they
             would
             seriously
             examine
             the
             first
             original
             ,
             and
             rise
             thereof
             from
             the
             
               Primigenial
               juice
            
             ,
             or
             liquamen
             ,
             the
             progress
             ,
             and
             perfection
             of
             its
             tinctures
             ,
             how
             many
             renovations
             ,
             or
             new
             tinctures
             it
             is
             capable
             of
             ;
             the
             vast
             difference
             between
             the
             Blood
             of
             old
             and
             young
             Animals
             ,
             (
             though
             ,
             it
             may
             be
             ,
             they
             are
             both
             univocal
             substances
             ,
             while
             in
             their
             integrity
             within
             the
             Vessels
             )
             with
             the
             specifick
             discriminations
             ,
             not
             only
             of
             that
             of
             any
             one
             Aquatick
             ,
             from
             any
             Volatil
             ,
             or
             Terrestrial
             ,
             but
             likewise
             of
             any
             one
             Species
             living
             in
             the
             same
             Element
             ,
             with
             these
             that
             enjoy
             the
             same
             Aliments
             ,
             but
             of
             a
             different
             Species
             .
             And
             lastly
             ,
             the
             variety
             of
             particular
             constitutions
             ,
             and
             singular
             properties
             of
             individual
             Animals
             ,
             radicated
             in
             the
             fountain
             of
             life
             ,
             or
             first
             original
             of
             the
             Blood.
             If
             these
             things
             ,
             and
             many
             more
             ,
             were
             truly
             inquired
             after
             (
             though
             the
             Cook
             be
             sometimes
             necessitated
             to
             throw
             away
             some
             of
             the
             Broth
             with
             the
             Scum
             )
             I
             doubt
             not
             but
             the
             Neoterick
             Invention
             of
             
               Transfusion
               of
               Blood
            
             ,
             would
             prove
             altogether
             ridiculous
             ,
             and
             the
             ancient
             mistake
             of
             too
             
             much
             Profusion
             of
             this
             treasure
             by
             Phlebotomy
             ,
             might
             suffer
             some
             reasonable
             checks
             from
             infallible
             Experience
             ,
             and
             sound
             reasons
             ,
             not
             here
             to
             be
             mentioned
             .
             There
             are
             truths
             in
             Natural
             Philosophy
             ,
             which
             (
             I
             doubt
             not
             )
             but
             sound
             reason
             and
             experience
             will
             convince
             the
             vain
             world
             of
             in
             due
             time
             .
          
        
         
           
             OBSERVATION
             XXIII
             .
          
           
             THis
             Observation
             is
             concerning
             the
             aliment
             and
             growth
             of
             Plants
             .
             The
             inquisitive
             wits
             of
             this
             ,
             and
             the
             last
             age
             ,
             having
             rejected
             the
             old
             opinion
             of
             the
             earths
             nourishing
             of
             Plants
             ,
             or
             being
             converted
             into
             their
             aliment
             ,
             have
             made
             many
             laudable
             Experiments
             for
             finding
             out
             the
             materials
             ,
             and
             means
             of
             their
             growth
             ,
             and
             vegetation
             ,
             such
             as
             Sir
             Francis
             Bacon's
             
               Observe
               of
               Germination
               ,
               Helmonts
            
             of
             a
             Willow
             ,
             and
             the
             Noble
             Mr.
             Boyl's
             of
             a
             Gourd
             ,
             &c.
             
             For
             though
             a
             Tree
             be
             cut
             down
             ,
             and
             the
             root
             thereof
             wax
             old
             in
             the
             earth
             ,
             and
             the
             stock
             die
             in
             the
             ground
             ,
             yet
             through
             the
             sent
             of
             Water
             ,
             it
             will
             bud
             ,
             as
             Iob
             speaketh
             ,
             Chap.
             14.
             7
             ,
             8
             ,
             9.
             
             I
             shall
             add
             a
             short
             remark
             of
             a
             Willow
             growing
             without
             earth
             .
             Upon
             the
             13
             of
             April
             1662
             ,
             I
             set
             a
             top
             branch
             of
             the
             
               Peach-leaf'd
               Willow
            
             in
             a
             Glass-viol
             ,
             among
             12
             ounces
             of
             pure
             Spring
             Water
             ,
             with
             three
             small
             buds
             upon
             the
             top
             thereof
             ,
             scarce
             yet
             discernable
             .
             The
             first
             ten
             or
             twelve
             dayes
             ,
             little
             white
             specks
             appeared
             upon
             the
             sides
             of
             the
             Willow
             ,
             like
             small
             drops
             of
             Quick-silver
             ,
             or
             like
             the
             first
             Bubbles
             that
             arise
             upon
             the
             fermentation
             of
             Ale
             or
             Wine
             ,
             but
             no
             consumption
             of
             the
             Water
             all
             this
             time
             .
             Indeed
             the
             Gemms
             ,
             which
             stood
             three
             inches
             above
             the
             Water
             ,
             did
             visibly
             swell
             about
             the
             twelfth
             day
             .
             About
             the
             fifteenth
             day
             ,
             I
             perceived
             small
             white
             roots
             within
             the
             
             Water
             ,
             upon
             several
             places
             of
             the
             Plant
             ,
             and
             observed
             the
             Liquor
             grow
             somewhat
             thick
             ,
             and
             decay
             in
             bulk
             considerably
             .
             Having
             perceived
             this
             ,
             I
             took
             another
             Glass
             of
             the
             same
             bigness
             ,
             with
             that
             wherein
             the
             Willow
             grew
             ,
             and
             having
             filled
             both
             top-full
             with
             Spring
             Water
             ,
             I
             observed
             clearly
             the
             consumption
             of
             the
             Water
             wherein
             the
             Plant
             stood
             ,
             to
             be
             so
             great
             ,
             that
             during
             
               May
               ,
               Iune
            
             ,
             and
             a
             great
             part
             of
             Iuly
             ,
             every
             week
             (
             at
             least
             )
             an
             ounce
             and
             an
             half
             ,
             or
             two
             ounces
             of
             it
             were
             insensibly
             spent
             :
             whereas
             the
             other
             Water
             ,
             standing
             by
             in
             an
             open
             Vessel
             of
             the
             same
             size
             ,
             made
             not
             waste
             of
             one
             spoonful
             in
             a
             whole
             moneth
             .
             About
             the
             middle
             of
             August
             ,
             the
             Water
             turned
             very
             thick
             ,
             and
             green
             ,
             like
             that
             whereon
             Duck-weed
             useth
             to
             grow
             ,
             and
             the
             fair
             white
             roots
             were
             all
             obscured
             from
             the
             sight
             ,
             although
             the
             Vessel
             by
             the
             multitude
             of
             roots
             was
             not
             capable
             of
             the
             third
             part
             of
             Water
             it
             received
             at
             first
             .
             At
             this
             time
             the
             branches
             were
             advanced
             to
             half
             the
             bigness
             ,
             and
             a
             much
             greater
             length
             ,
             than
             the
             whole
             stock
             ,
             at
             its
             first
             planting
             ;
             and
             the
             leaves
             of
             as
             fresh
             a
             verdure
             ,
             as
             any
             Willow
             in
             the
             fields
             .
             Thus
             ,
             having
             observed
             ,
             that
             a
             tree
             of
             four
             ounces
             weight
             ,
             could
             in
             three
             moneths
             time
             ,
             and
             little
             more
             ,
             consume
             insensibly
             ,
             seven
             or
             eight
             times
             its
             own
             weight
             of
             pure
             Water
             ,
             without
             the
             warm
             preservation
             of
             the
             earth
             ,
             and
             by
             its
             own
             proper
             digestion
             ,
             to
             thicken
             the
             remnant
             of
             the
             Water
             ,
             that
             it
             might
             serve
             for
             lorication
             of
             the
             tender
             fibres
             of
             the
             roots
             ,
             I
             took
             the
             Glass
             ,
             the
             Tree
             ,
             and
             all
             ,
             and
             threw
             them
             over
             a
             Window
             ,
             supposing
             it
             needless
             to
             recruit
             the
             Water
             any
             more
             ,
             and
             judging
             it
             impossible
             without
             the
             warm
             guard
             of
             the
             earth
             ,
             that
             the
             naked
             Tree
             could
             be
             preserved
             in
             Winter
             :
             yet
             it
             had
             the
             good
             fortune
             to
             fall
             among
             some
             thick
             Herbs
             in
             the
             corner
             of
             a
             little
             Garden
             ,
             where
             (
             after
             it
             had
             lien
             all
             Winter
             )
             it
             
             was
             found
             ,
             and
             brought
             back
             to
             me
             ,
             the
             branches
             fairly
             budding
             in
             April
             ,
             the
             whole
             Tree
             fresh
             and
             green
             ,
             yet
             very
             little
             Water
             was
             left
             in
             the
             Glass
             ,
             by
             reason
             ,
             as
             I
             judged
             ,
             it
             had
             fallen
             upon
             its
             side
             .
             Then
             I
             endeavoured
             to
             keep
             Water
             about
             it
             ,
             but
             the
             Stock
             filling
             the
             neck
             of
             the
             Viol
             ,
             and
             the
             Roots
             the
             whole
             body
             thereof
             ,
             the
             starved
             Plant
             died
             in
             May
             ,
             after
             it
             had
             lived
             a
             whole
             year
             without
             earth
             .
             From
             this
             it
             would
             seem
             ,
             that
             this
             kind
             of
             Tree
             ,
             (
             and
             it
             may
             be
             ,
             many
             moe
             )
             doth
             dissipat
             insensibly
             six
             times
             more
             Liquor
             ,
             than
             it
             doth
             assimilar
             ,
             and
             by
             consequence
             ,
             that
             a
             great
             quantity
             of
             moisture
             is
             necessary
             for
             maintainance
             of
             great
             Woods
             .
             Neither
             is
             there
             any
             way
             so
             advantagious
             for
             draining
             moist
             ground
             ,
             where
             there
             are
             no
             living
             Springs
             ,
             as
             that
             of
             planting
             abundance
             of
             Timber
             ,
             which
             will
             best
             agree
             with
             that
             kind
             of
             soyl
             :
             for
             by
             this
             means
             ,
             what
             was
             formerly
             noisome
             ,
             and
             superfluous
             ,
             is
             now
             converted
             partly
             into
             the
             useful
             aliment
             of
             the
             Timber
             ,
             and
             partly
             sent
             abroad
             in
             insensible
             exhalations
             ,
             which
             (
             according
             to
             the
             nature
             of
             the
             emitting
             Plants
             )
             prove
             either
             very
             noisome
             ,
             or
             wholsome
             to
             the
             Neighbour-Inhabitants
             .
             Great
             care
             therefore
             would
             be
             had
             in
             the
             choise
             of
             such
             Trees
             ,
             as
             are
             to
             be
             planted
             in
             such
             moist
             ground
             ,
             as
             are
             near
             to
             mens
             dwellings
             ,
             or
             places
             of
             concurse
             .
             They
             are
             not
             fools
             ,
             who
             prefer
             Firs
             ,
             and
             Lime-trees
             in
             their
             Avenues
             to
             Oak
             and
             Elme
             .
             Let
             the
             effects
             of
             the
             Atomical
             exhalations
             of
             Alder
             and
             Oak
             upon
             fine
             Linnen
             ,
             and
             white
             Skins
             be
             more
             particularly
             noticed
             .
          
           
             Having
             spoken
             somewhat
             of
             the
             aliment
             and
             growth
             of
             Plants
             ,
             I
             shall
             in
             the
             next
             place
             give
             a
             short
             hint
             at
             the
             motion
             of
             their
             aliment
             ,
             especially
             of
             Trees
             .
             That
             the
             alimentary
             juice
             of
             Plants
             ,
             is
             much
             thinner
             ,
             than
             that
             of
             Animals
             ,
             no
             man
             ,
             I
             suppose
             ,
             will
             deny
             ,
             seing
             that
             is
             conveyed
             
             thorow
             the
             trunck
             ,
             or
             body
             of
             the
             Plants
             ,
             by
             inperceptible
             pores
             ;
             but
             this
             (
             for
             the
             most
             part
             )
             is
             sent
             thorow
             all
             the
             members
             ,
             through
             patent
             and
             manifest
             Vessels
             .
             But
             how
             the
             nourishing
             ,
             and
             vital
             juice
             in
             Plants
             doth
             move
             ,
             and
             by
             what
             passages
             ,
             hath
             not
             yet
             been
             made
             known
             ,
             by
             any
             that
             I
             have
             seen
             .
             I
             made
             once
             a
             few
             Observations
             ,
             for
             trying
             of
             the
             motion
             of
             the
             aliment
             of
             Trees
             ,
             which
             bred
             in
             me
             this
             conjecture
             .
             The
             nutritive
             juice
             of
             Trees
             is
             transmitted
             both
             to
             the
             roots
             and
             branches
             ,
             through
             the
             heart
             ,
             or
             pitch
             ,
             and
             woody
             pores
             of
             the
             Timber
             ,
             and
             when
             it
             is
             come
             to
             the
             extream
             parts
             ,
             it
             returns
             again
             from
             the
             tops
             of
             the
             roots
             and
             branches
             ,
             between
             the
             bark
             and
             timber
             ,
             into
             these
             forenamed
             interior
             passages
             ,
             and
             so
             back
             to
             the
             extremities
             again
             ,
             and
             that
             continually
             ,
             so
             long
             as
             the
             life
             remains
             .
             And
             because
             the
             substance
             of
             that
             skin
             ,
             or
             bark
             ,
             which
             invests
             the
             fibres
             of
             the
             root
             ,
             is
             more
             open
             and
             porous
             ,
             than
             that
             which
             is
             upon
             the
             outward
             branches
             :
             therefore
             it
             seems
             ,
             that
             so
             much
             as
             is
             superadded
             to
             the
             stock
             of
             the
             former
             aliment
             ,
             from
             the
             earth
             ,
             is
             conveyed
             to
             the
             heart
             and
             pitch
             ,
             by
             means
             of
             ,
             and
             together
             with
             ,
             that
             part
             of
             the
             retrograd
             juice
             ,
             which
             returns
             from
             nourishing
             ,
             and
             enlivening
             the
             timber
             of
             the
             root-branches
             ,
             (
             for
             it
             is
             an
             easie
             Experiment
             ,
             to
             make
             the
             top
             of
             any
             Tree
             become
             root
             ,
             by
             laying
             it
             down
             )
             and
             receives
             the
             impressions
             of
             the
             life
             of
             the
             Tree
             ,
             common
             to
             the
             whole
             mass
             of
             alimentary
             juice
             ,
             like
             the
             I
             hyll
             in
             Animals
             mixed
             with
             the
             blood
             of
             the
             Veni-cave
             ,
             before
             it
             come
             to
             the
             heart
             .
          
           
             This
             motion
             is
             not
             to
             be
             thought
             alwayes
             alike
             swift
             ,
             or
             of
             equal
             celerity
             :
             for
             the
             vital
             juice
             of
             the
             Tree
             becomes
             so
             thick
             and
             oleagenous
             in
             the
             Winter
             ,
             that
             the
             motion
             thereof
             to
             the
             outward
             ,
             is
             scarce
             discernable
             (
             though
             the
             preparation
             of
             the
             Gemmes
             ,
             both
             for
             leaves
             and
             flowers
             ,
             
             are
             observed
             by
             the
             curious
             ,
             and
             can
             be
             distinguished
             ,
             even
             in
             the
             coldest
             seasons
             )
             and
             the
             returns
             inward
             are
             in
             so
             small
             quantities
             ,
             that
             they
             are
             rather
             like
             vapours
             ,
             than
             liquid
             juice
             .
             Indeed
             ,
             some
             Trees
             ,
             when
             their
             root-branches
             are
             cut
             (
             even
             in
             Winter
             )
             will
             yeeld
             no
             small
             quantity
             of
             an
             acid
             liquor
             ,
             which
             by
             addition
             of
             the
             recent
             Leffas
             from
             the
             earth
             ,
             smells
             evidently
             of
             the
             Matrix
             ,
             from
             which
             it
             did
             proceed
             .
             Moreover
             ,
             the
             passages
             especially
             from
             the
             branches
             to
             the
             Trunk
             ,
             are
             so
             straitned
             and
             contracted
             ,
             that
             the
             bark
             cleaveth
             to
             the
             Timber
             ,
             as
             every
             Wood-man
             knows
             .
             But
             so
             soon
             as
             the
             warm
             Spring
             hath
             attenuated
             the
             ever-flowing
             juice
             in
             the
             whole
             Tree
             ,
             then
             doth
             it
             become
             turgid
             ,
             and
             more
             aqueous
             over
             all
             :
             the
             passages
             ,
             and
             channels
             both
             in
             the
             trunk
             ,
             and
             among
             the
             tunicles
             ,
             and
             particular
             skinnes
             ,
             are
             so
             palpably
             filled
             with
             this
             vital
             juice
             ,
             that
             having
             no
             sufficient
             place
             to
             be
             comprehended
             in
             ,
             it
             putteth
             forth
             new
             growths
             both
             in
             the
             top
             ,
             and
             in
             the
             root
             ,
             which
             may
             be
             easily
             seen
             to
             have
             more
             pitch
             than
             wood
             ,
             and
             to
             be
             sealed
             on
             the
             extremity
             ,
             with
             the
             vestiges
             of
             a
             future
             Gemm
             ;
             that
             by
             the
             former
             ,
             they
             may
             the
             more
             freely
             receive
             the
             vital
             influences
             from
             within
             ,
             and
             by
             the
             latter
             ,
             may
             be
             secured
             from
             the
             depredation
             of
             the
             external
             Air.
             
          
           
             To
             prove
             the
             motion
             
               ad
               extra
            
             ,
             or
             to
             the
             extremities
             of
             the
             branches
             ;
             take
             the
             branch
             of
             any
             ordinary
             Tree
             ,
             about
             the
             bigness
             of
             a
             mans
             wrist
             ;
             make
             it
             bare
             near
             the
             body
             of
             the
             Tree
             of
             all
             bark
             ,
             and
             subjacent
             tunicles
             (
             for
             every
             Tree
             according
             to
             its
             kind
             ,
             hath
             moe
             or
             fewer
             skins
             ,
             which
             serve
             for
             Veins
             ,
             within
             the
             strong
             outmost
             Cortex
             )
             at
             least
             for
             the
             breadth
             of
             a
             span
             ,
             or
             two
             hand-breadth
             .
             Then
             tye
             up
             the
             place
             ,
             so
             excorticated
             with
             a
             compost
             ,
             made
             of
             horse-dung
             mixed
             with
             earth
             ;
             let
             it
             stand
             so
             from
             May
             ,
             
             till
             November
             .
             Then
             cut
             off
             the
             branch
             ,
             a
             little
             above
             the
             Compost
             ,
             near
             the
             body
             of
             the
             Tree
             ,
             and
             you
             shall
             find
             it
             living
             and
             fresh
             ,
             like
             the
             rest
             of
             the
             branches
             :
             yea
             ,
             small
             roots
             shall
             evidently
             appear
             to
             have
             come
             forth
             under
             the
             Compost
             near
             the
             bark
             ,
             but
             not
             under
             the
             bared
             place
             .
             This
             branch
             in
             many
             kind
             of
             Trees
             being
             planted
             ,
             will
             hold
             ,
             though
             not
             in
             all
             .
             I
             say
             then
             ,
             seing
             the
             foresaid
             bough
             is
             nourished
             from
             May
             till
             November
             ,
             it
             is
             necessary
             ,
             that
             it
             receive
             nutriment
             from
             the
             body
             of
             the
             Tree
             ,
             by
             the
             internal
             porosities
             thereof
             :
             for
             the
             bark
             being
             discontinued
             by
             excortication
             ,
             can
             send
             nothing
             upward
             towards
             the
             top
             of
             the
             bough
             ;
             and
             if
             it
             received
             nothing
             from
             the
             root
             ,
             it
             would
             wither
             in
             a
             few
             dayes
             .
             Yea
             ,
             leave
             the
             discovered
             part
             naked
             ,
             but
             for
             a
             few
             dayes
             ,
             and
             of
             necessity
             the
             branch
             dieth
             ,
             the
             aliment
             thereof
             being
             exhausted
             by
             the
             Air
             ,
             before
             it
             can
             reach
             the
             extremities
             of
             the
             bough
             .
          
           
             That
             the
             
               Vital
               Balsome
            
             of
             the
             Tree
             returns
             from
             the
             extremities
             by
             the
             internal
             bark
             ,
             and
             inward
             superfice
             of
             the
             external
             ,
             together
             with
             the
             smooth
             outward
             part
             of
             the
             t●unck
             ,
             although
             the
             necessity
             of
             both
             timber
             and
             bark
             in
             all
             Incisions
             ,
             and
             Inoculations
             ,
             might
             perswade
             the
             judicious
             ,
             and
             the
             visible
             course
             of
             the
             juice
             of
             the
             Sycamor
             in
             February
             ,
             and
             of
             the
             Birch
             in
             March
             ,
             upon
             the
             cutting
             of
             any
             small
             branch
             ,
             might
             convince
             any
             curious
             beholder
             ;
             yet
             the
             knot
             or
             callus
             ,
             that
             is
             made
             upon
             grafted
             Trees
             ,
             will
             better
             inform
             the
             ignorant
             :
             for
             this
             knot
             being
             alwayes
             upon
             the
             shoulder
             ,
             or
             root
             of
             the
             Graff
             ,
             and
             never
             upon
             the
             top
             of
             the
             Stock
             ,
             doth
             evince
             clearly
             ,
             that
             it
             is
             made
             by
             restagnation
             ,
             of
             the
             descending
             ,
             and
             not
             of
             the
             ascending
             juice
             :
             otherwise
             ,
             why
             doth
             it
             not
             swell
             the
             top
             of
             the
             Stock
             ,
             as
             well
             as
             the
             root
             of
             the
             Graff
             ?
             Or
             why
             doth
             it
             not
             extuberat
             in
             any
             other
             place
             of
             the
             Graff
             ?
             These
             
             are
             accidental
             varices
             ,
             which
             can
             hardly
             be
             shunned
             in
             Imping
             ,
             seing
             the
             top
             of
             the
             Stock
             (
             except
             when
             it
             is
             very
             young
             and
             succulent
             )
             doth
             not
             receive
             so
             kindly
             ,
             as
             it
             ought
             ,
             the
             retrograd
             sap
             ,
             although
             all
             that
             is
             sent
             out
             to
             the
             Graff
             must
             ascend
             thorow
             the
             pores
             of
             the
             Stock
             .
             Hence
             many
             times
             a
             considerable
             part
             of
             the
             Stock
             is
             mortified
             ,
             because
             although
             abundance
             of
             aliment
             ascends
             to
             the
             head
             or
             top
             thereof
             ,
             yet
             no
             more
             of
             it
             goes
             to
             the
             branches
             ,
             but
             what
             is
             bestowed
             upon
             the
             Graff
             ,
             a
             great
             part
             of
             the
             rest
             being
             exhaled
             by
             the
             Air
             (
             especially
             in
             big
             Stocks
             )
             and
             consequently
             ,
             the
             place
             defrauded
             of
             its
             nourishment
             :
             no
             other
             wayes
             than
             when
             the
             motion
             of
             the
             vital
             sap
             faileth
             ,
             either
             in
             the
             whole
             ,
             or
             in
             part
             ,
             a
             total
             decay
             or
             particular
             mortification
             of
             some
             part
             necessarily
             follows
             ,
             as
             in
             the
             Stemms
             of
             annual
             Plants
             ,
             and
             mortified
             tops
             of
             the
             Ectrapelous
             branches
             (
             that
             I
             may
             so
             call
             them
             )
             of
             
               Willows
               ,
               Plumbs
            
             ,
             &c.
             we
             may
             observe
             every
             Autumn
             .
          
        
         
           
             OBSERVATION
             XXIV
             .
          
           
             
               Sir
               ,
            
          
           
             
               I
               Was
               not
               a
               little
               surprised
               ,
               at
               the
               receit
               of
               yours
               ,
               when
               I
               had
               considered
               your
               desire
               in
               it
               ,
               being
               prest
               with
               two
               difficulties
               ,
               which
               seemed
               equally
               hard
               to
               evite
               .
               The
               one
               ,
               to
               give
               you
               my
               judgement
               in
               a
               matter
               wherein
               I
               have
               been
               so
               little
               conversant
               my self
               ,
               and
               have
               had
               the
               steps
               of
               no
               other
               to
               follow
               ,
               never
               one
               having
               hitherto
               touched
               that
               subject
               in
               writting
               ;
               I
               mean
               of
               Coals
               ,
               and
               other
               Minerals
               of
               that
               nature
               ,
               their
               Course
               ,
               and
               other
               things
               relating
               thereunto
               ;
               the
               observation
               whereof
               (
               I
               grant
               )
               wants
               not
               its
               own
               pleasure
               ,
               and
               usefulness
               .
               The
               other
               ,
               to
               refuse
               the
               desire
               of
               a
               friend
               ,
               when
               importuned
               ,
               
               to
               whom
               I
               owe
               my self
               ,
               by
               many
               obligations
               .
               This
               last
               having
               prevailed
               ,
               hath
               determined
               me
               to
               assay
               the
               overcoming
               of
               the
               first
               .
               And
               though
               I
               am
               confident
               ,
               what
               account
               I
               can
               give
               you
               ,
               shall
               give
               but
               very
               little
               satisfaction
               :
               yet
               I
               adventure
               to
               offer
               it
               ,
               such
               as
               it
               is
               ,
               very
               freely
               in
               the
               following
               discourse
               ,
               wherein
               you
               are
               not
               to
               expect
               ,
               that
               I
               will
               meddle
               with
               some
               questions
               ,
               thereanent
               ,
               which
               might
               be
               more
               curious
               ,
               and
               pleasant
               ,
               then
               profitable
               ,
               or
               satisfying
               ,
               such
               as
               ,
               if
               Coal
               ,
               and
               Free-stone
               ,
               which
               keep
               one
               course
               ,
               and
               have
               the
               same
               accidental
               qualities
               ,
               have
               been
               created
               in
               the
               beginning
               ,
               in
               their
               perfection
               ,
               as
               wee
               now
               find
               them
               ,
               and
               since
               that
               time
               only
               preserved
               ,
               as
               they
               were
               created
               for
               the
               use
               of
               men
               ,
               to
               whom
               all
               sublunary
               things
               were
               made
               subfervient
               ?
               Or
               ,
               if
               they
               have
               been
               but
               produced
               gradually
               ,
               as
               they
               speak
               of
               Gold
               ,
               and
               other
               Minerals
               ,
               by
               the
               influence
               of
               the
               Sun
               ,
               in
               the
               bowels
               of
               the
               Earth
               ?
               And
               if
               their
               production
               be
               of
               that
               nature
               ,
               out
               of
               what
               matter
               they
               are
               formed
               ?
               These
               things
               being
               above
               my
               reach
               ,
               I
               shall
               leave
               their
               inquiry
               ,
               to
               those
               that
               are
               knowing
               in
               the
               secrets
               of
               Nature
               ,
               and
               shall
               therefore
               give
               you
               a
               narration
               ,
               of
               what
               either
               I
               have
               observed
               of
               these
               things
               ,
               which
               occurr
               in
               the
               Winning
               of
               Coal
               in
               my
               own
               experience
               ,
               or
               by
               conversing
               with
               others
               of
               more
               experience
               than
               my self
               ,
               in
               doing
               whereof
               ,
               I
               shall
               follow
               this
               Method
               .
            
          
           
             First
             ,
             I
             shall
             speak
             of
             these
             things
             that
             are
             common
             to
             all
             Coal
             ,
             wherein
             they
             all
             agree
             ,
             and
             which
             are
             ,
             as
             it
             were
             ,
             essential
             to
             all
             ,
             and
             of
             there
             differences
             ,
             which
             are
             but
             accidental
             ,
             and
             gradual
             sometimes
             ,
             and
             yet
             are
             abundantly
             conspicuous
             ,
             and
             causeth
             different
             effects
             in
             the
             working
             ;
             as
             their
             Dipps
             and
             Rise
             ,
             and
             Streek
             ,
             for
             so
             are
             they
             termed
             .
          
           
             Secondly
             ,
             of
             some
             things
             ,
             which
             are
             but
             accidental
             to
             Coal
             ,
             
             and
             yet
             so
             ordinary
             ,
             that
             scarcely
             any
             is
             found
             without
             them
             ,
             in
             lesser
             or
             greater
             degrees
             ;
             such
             are
             Gae's
             ,
             and
             Dykes
             ,
             that
             alter
             the
             natural
             Course
             of
             the
             Metalls
             ,
             very
             incident
             to
             every
             Coal
             ,
             though
             in
             some
             less
             frequent
             ,
             conform
             to
             the
             nature
             and
             kind
             of
             the
             ground
             ,
             where
             the
             Coal
             is
             .
          
           
             Thirdly
             ,
             I
             shall
             speak
             something
             of
             Damps
             ,
             and
             of
             their
             different
             causes
             ,
             and
             effects
             :
             of
             Wild-fire
             ,
             and
             other
             such
             like
             things
             ,
             which
             are
             met
             with
             in
             the
             working
             of
             Coal
             .
          
           
             And
             lastly
             ,
             of
             the
             best
             way
             for
             trying
             grounds
             to
             find
             Coal
             ,
             where
             never
             any
             hath
             been
             hitherto
             discovered
             :
             of
             carrying
             on
             of
             Levels
             ,
             for
             draining
             the
             water
             of
             Coal
             and
             making
             it
             workable
             .
          
           
             It
             is
             to
             be
             cosidered
             ,
             that
             all
             Free-stone
             ,
             though
             of
             different
             natures
             ,
             hath
             the
             same
             course
             ,
             with
             the
             Coal
             ,
             that
             ly
             either
             above
             them
             ,
             or
             below
             them
             ,
             except
             it
             be
             accidentally
             ,
             interrupted
             :
             therefore
             ,
             whatsoever
             is
             spoken
             of
             the
             one
             ,
             is
             applicable
             to
             the
             other
             .
             And
             so
             we
             find
             in
             Digging
             or
             Sinking
             ,
             that
             after
             the
             Clay
             is
             past
             ,
             which
             keeps
             no
             course
             ,
             all
             Metals
             ,
             as
             Stone
             ,
             and
             Tilles
             (
             which
             are
             Seems
             of
             black
             Stone
             ,
             and
             participat
             much
             of
             the
             nature
             of
             Coal
             )
             ly
             one
             above
             another
             ,
             and
             keep
             a
             regular
             Course
             ;
             wherein
             the
             three
             things
             most
             remarkable
             are
             their
             Dipp
             ,
             and
             Rise
             ,
             and
             their
             Streek
             ,
             as
             it
             is
             termed
             .
          
           
             The
             Dipp
             ,
             and
             Rise
             ,
             are
             nothing
             but
             a
             declining
             of
             the
             whole
             body
             of
             the
             Metalls
             .
             And
             this
             general
             holds
             ,
             that
             all
             of
             them
             from
             their
             Center
             rises
             ,
             till
             they
             be
             at
             the
             very
             surface
             of
             the
             Earth
             ;
             some
             only
             at
             a
             foot
             or
             two
             foot
             ,
             some
             at
             an
             ells
             distance
             from
             the
             surface
             ,
             which
             is
             here
             termed
             a
             Cropping
             :
             and
             whether
             Coal
             or
             Stone
             ,
             the
             nearer
             they
             come
             to
             the
             surface
             ,
             the
             softer
             they
             become
             ,
             till
             at
             
             last
             they
             are
             converted
             ,
             if
             it
             be
             a
             Stone
             ,
             to
             a
             very
             Sand
             ,
             and
             if
             Coal
             ,
             to
             a
             Dross
             ,
             which
             will
             not
             burn
             .
          
           
             This
             d●clining
             or
             Dipping
             ,
             of
             the
             Coal
             ,
             is
             sometimes
             greater
             ,
             and
             sensible
             ,
             sometimes
             lesser
             ,
             and
             almost
             insensible
             .
             There
             being
             some
             ,
             that
             if
             you
             consider
             the
             declination
             ,
             it
             will
             not
             be
             found
             one
             foot
             in
             ten
             ;
             some
             one
             foot
             in
             twenty
             ,
             or
             one
             in
             thirty
             .
             Whereas
             in
             others
             it
             will
             be
             one
             foot
             in
             three
             ,
             or
             one
             in
             five
             .
             And
             sometimes
             it
             hath
             its
             Course
             from
             the
             Center
             of
             the
             Earth
             ,
             almost
             in
             a
             perpendicular
             to
             the
             surface
             ,
             it
             cutting
             it
             ,
             near
             to
             a
             
               right
               Angle
            
             .
             The
             first
             sort
             ,
             they
             term
             Flate-broad-coal
             ,
             in
             regard
             of
             the
             plainness
             ,
             and
             evenness
             of
             its
             Course
             .
             The
             next
             ,
             they
             call
             Hinging-coal
             .
             The
             last
             is
             called
             Edge-Coal
             .
             The
             first
             is
             the
             most
             profitable
             ,
             in
             regard
             ,
             that
             it
             's
             long
             before
             the
             Coal-hewers
             can
             reach
             the
             Cropp
             ,
             and
             consequently
             the
             more
             of
             it
             is
             workable
             .
             The
             second
             and
             third
             sort
             ,
             are
             sometimes
             of
             their
             own
             nature
             ,
             more
             firm
             ,
             and
             fitter
             for
             burning
             ,
             but
             less
             of
             them
             can
             be
             reached
             in
             working
             .
             The
             Course
             of
             all
             the
             three
             is
             most
             perceptible
             in
             the
             three
             following
             Schematisms
             .
          
           
             
               Figure
               1.
               
            
          
           
             In
             all
             the
             three
             Figures
             ,
             the
             point
             B
             is
             the
             Cropp
             of
             the
             Coal
             .
             The
             Line
             B
             C
             is
             the
             body
             of
             the
             Coal
             declining
             or
             the
             Dipp
             from
             the
             Cropp
             .
             A
             C
             is
             the
             perpendicular
             ,
             falling
             from
             the
             Horizontal
             Line
             ,
             whereby
             the
             true
             declination
             or
             Dipp
             of
             the
             Coal
             is
             found
             .
             So
             that
             after
             you
             have
             found
             your
             Coal
             at
             B
             ,
             you
             must
             set
             down
             your
             Sink
             at
             the
             point
             A.
             In
             the
             Flat-broad-Coal
             ,
             which
             we
             suppose
             only
             to
             decline
             ,
             three
             fathoms
             in
             sixty
             ;
             the
             Sink
             ,
             that
             answers
             to
             the
             perpendicular
             A
             C
             ,
             will
             be
             of
             deepness
             three
             fathoms
             .
             
             If
             the
             distance
             B
             A
             ,
             be
             supposed
             to
             be
             120
             fathoms
             alongst
             the
             Grass
             ,
             or
             surface
             ,
             then
             will
             the
             deepness
             of
             the
             Sink
             be
             six
             fathom
             ,
             and
             so
             forth
             .
             In
             the
             second
             ,
             if
             the
             Coal
             be
             supposed
             to
             decline
             one
             fathom
             in
             three
             ,
             the
             Sink
             A
             C
             ,
             being
             set
             down
             at
             the
             same
             distance
             from
             the
             Cropp
             B
             ,
             with
             the
             former
             ,
             it
             will
             prove
             thirty
             fathom
             deep
             .
             If
             the
             said
             distance
             be
             doubled
             ,
             it
             becomes
             sixty
             fathom
             deep
             ,
             and
             so
             forth
             .
             In
             the
             third
             ,
             keeping
             that
             same
             distance
             alongst
             the
             surface
             ,
             you
             shall
             not
             encounter
             the
             Coal
             with
             a
             Perpendicular
             Sink
             ,
             because
             of
             its
             great
             declination
             ,
             and
             therefore
             through
             want
             of
             Air
             ,
             and
             other
             difficulties
             ,
             you
             cannot
             dig
             so
             deep
             ,
             as
             is
             necessary
             to
             that
             effect
             ,
             except
             the
             Sink
             should
             be
             made
             to
             decline
             ,
             as
             doth
             the
             Line
             A
             D.
             All
             these
             Dipps
             are
             to
             be
             seen
             in
             several
             places
             of
             Lothian
             .
             The
             first
             is
             most
             conspicuous
             in
             the
             Earl
             of
             Wintons
             ground
             at
             Tranent
             ,
             where
             the
             Coal
             ,
             and
             other
             Metals
             are
             extraordinary
             flat
             and
             even
             .
             The
             second
             is
             within
             the
             said
             Lordship
             of
             Tranent
             ,
             in
             a
             piece
             of
             ground
             ,
             called
             Wester-Fauside
             .
             The
             third
             in
             Lonhead
             of
             Laswaid
             ,
             which
             pertains
             to
             Sir
             
               Iohn
               Nicolson
            
             of
             Nicolson
             :
             and
             in
             many
             other
             places
             ,
             one
             may
             see
             very
             different
             declinations
             ,
             who
             is
             curious
             to
             observe
             them
             .
          
           
             From
             this
             general
             position
             of
             the
             Dipp
             ,
             and
             Cropp
             of
             all
             
               free
               Metals
            
             ,
             there
             is
             one
             consequent
             ,
             which
             is
             no
             uncouth
             Observation
             ,
             namely
             that
             these
             Metals
             rising
             from
             their
             Dipp
             to
             a
             Cropp
             ,
             every
             one
             of
             them
             riseth
             in
             their
             proper
             course
             ,
             if
             none
             of
             these
             things
             whereof
             we
             shall
             treat
             hereafter
             interveen
             ,
             and
             make
             an
             alteration
             ,
             that
             is
             the
             Coal
             or
             Stone
             ,
             which
             is
             lowest
             ,
             comes
             farrest
             out
             in
             its
             Cropping
             ,
             which
             is
             easily
             understood
             by
             the
             subsequent
             Schematism
             .
          
           
             
               Figure
               4.
               
            
          
           
             Wherein
             the
             Line
             A
             M
             represents
             the
             surface
             of
             the
             Earth
             .
             C
             D.
             E
             F.
             G
             H.
             I
             K.
             L
             M
             ,
             are
             so
             many
             several
             Metals
             ,
             lying
             in
             course
             one
             above
             another
             .
             Suppose
             C
             D
             were
             a
             Stone
             ,
             and
             the
             Roof
             of
             the
             Coal
             E
             F
             (
             for
             so
             they
             term
             the
             Stone
             ,
             immediatly
             next
             above
             the
             Coal
             )
             and
             G
             H
             ,
             I
             K
             ,
             were
             other
             two
             Stones
             ,
             interveening
             between
             the
             Coals
             E
             F
             ,
             and
             L
             M
             ,
             then
             if
             the
             Cropp
             of
             the
             uppermost
             Coal
             be
             found
             at
             F
             ,
             the
             Crop
             of
             the
             Stone
             above
             it
             ,
             must
             be
             found
             back
             ,
             at
             the
             point
             D
             ,
             and
             the
             Cropp
             of
             the
             Coal
             under
             it
             ,
             which
             is
             L
             M
             ,
             must
             be
             found
             at
             M.
             And
             this
             distance
             of
             Cropp
             is
             proportioned
             by
             the
             length
             of
             the
             perpendicular
             between
             them
             ,
             and
             the
             quantity
             of
             their
             declination
             .
             For
             ,
             the
             more
             even
             and
             flat
             a
             Coal
             is
             in
             its
             course
             ,
             and
             other
             Metals
             ,
             above
             and
             below
             ,
             the
             farder
             doth
             the
             Cropp
             of
             the
             lowest
             Coal
             advance
             before
             the
             Cropp
             of
             the
             uppermost
             .
             For
             illustration
             whereof
             ,
             let
             us
             suppose
             in
             two
             several
             grounds
             ,
             two
             Coals
             ,
             between
             which
             ,
             there
             is
             an
             equal
             distance
             of
             perpendicular
             .
             And
             suppose
             the
             Metals
             in
             the
             one
             ground
             to
             decline
             at
             13
             to
             24
             ,
             the
             other
             at
             13
             to
             16
             ,
             then
             will
             the
             distance
             between
             the
             Cropps
             in
             the
             two
             grounds
             be
             very
             considerable
             ,
             as
             may
             be
             represented
             by
             the
             two
             following
             Figures
             .
          
           
             
               Figure
               5.
               
            
          
           
             Suppose
             then
             ,
             that
             D
             I
             ,
             is
             of
             equal
             length
             in
             both
             Triangles
             ,
             which
             is
             the
             perpendicular
             ,
             between
             the
             two
             Coals
             :
             yet
             D
             F
             in
             the
             fifth
             Figure
             ,
             is
             much
             longer
             than
             D
             F
             in
             the
             6.
             
             And
             the
             reason
             is
             evident
             ,
             because
             the
             Angle
             D
             I
             F
             ,
             in
             the
             5
             ,
             is
             greater
             then
             the
             Angle
             D
             I
             F
             in
             the
             6
             :
             and
             therefore
             the
             Base
             D
             F
             ,
             which
             is
             subtended
             by
             the
             greater
             Angle
             in
             the
             5
             ,
             must
             be
             greater
             then
             the
             Base
             D
             F
             ,
             which
             is
             subtended
             by
             the
             lesser
             Angle
             in
             the
             6
             ,
             which
             Euclide
             proves
             in
             his
             24
             Proposition
             of
             his
             first
             Book
             ,
             and
             is
             demonstrat
             by
             Proclus
             in
             the
             Scholium
             to
             the
             4
             th
             Proposition
             of
             the
             same
             Book
             .
          
           
             By
             this
             is
             made
             to
             appear
             the
             profitableness
             of
             a
             Flat-Coal
             ,
             beyond
             a
             Hinging-Coal
             ,
             which
             was
             touched
             before
             ,
             in
             regard
             that
             having
             the
             Sinks
             of
             equal
             deepness
             in
             both
             ,
             there
             is
             much
             more
             of
             the
             Flater-Coal
             to
             be
             wrought
             ,
             before
             it
             Cropp
             out
             ,
             then
             of
             the
             Hinging
             ,
             as
             there
             is
             a
             difference
             between
             the
             Lines
             D
             F
             in
             the
             first
             and
             second
             Figure
             ,
             or
             between
             the
             Lines
             I
             F
             ,
             in
             the
             same
             .
          
           
           
             If
             it
             be
             enquired
             ,
             if
             in
             rising
             grounds
             ,
             where
             there
             is
             a
             considerable
             ascent
             above
             ground
             ,
             the
             Coal
             keeps
             a
             proportion
             in
             its
             Rising
             and
             Dipping
             with
             the
             ascent
             and
             descent
             of
             the
             ground
             above
             ?
             I
             answer
             ,
             there
             is
             no
             certain
             and
             constant
             proportion
             kept
             ,
             whatever
             sometimes
             may
             happen
             .
             For
             I
             have
             observed
             some
             Coals
             upon
             grounds
             of
             a
             considerable
             ascent
             ,
             and
             their
             Dipp
             run
             quite
             contrary
             to
             the
             descent
             of
             the
             Hill
             :
             and
             others
             have
             had
             a
             quite
             contrary
             course
             to
             that
             ,
             and
             have
             declined
             ,
             or
             dipped
             with
             the
             declination
             of
             the
             ground
             above
             .
             But
             in
             the
             Streek
             (
             whereof
             I
             shall
             speak
             a
             little
             hereafter
             )
             there
             is
             more
             proportion
             ordinarily
             to
             be
             remarked
             .
          
           
             There
             remains
             only
             one
             Question
             about
             the
             Dipps
             ,
             and
             Risings
             of
             Coals
             ,
             which
             I
             shall
             a
             little
             consider
             ,
             having
             encountered
             different
             judgements
             anent
             it
             ,
             in
             conversing
             with
             persons
             ,
             who
             had
             experience
             in
             Coal
             ,
             viz.
             whether
             Coal
             and
             other
             Metals
             ,
             after
             they
             have
             declined
             such
             a
             length
             from
             their
             Cropp
             ,
             suppose
             from
             West
             to
             East
             ,
             take
             another
             course
             ,
             and
             rise
             to
             the
             same
             point
             ,
             to
             which
             formerly
             they
             dipped
             ?
          
           
             
               Figure
               7.
               
            
          
           
             As
             if
             the
             
               Coal
               dipped
            
             from
             A
             ,
             which
             is
             the
             Cropp
             ,
             to
             B
             ,
             which
             should
             be
             the
             Center
             of
             that
             Body
             ;
             and
             after
             that
             rise
             to
             C
             ?
             Or
             if
             it
             should
             continue
             its
             declination
             thorow
             
             B
             to
             D
             ,
             which
             is
             Antipodes
             to
             us
             ?
             I
             shall
             not
             offer
             to
             determine
             in
             a
             matter
             wherein
             there
             can
             be
             so
             little
             certainty
             attained
             ,
             but
             shall
             give
             my
             opinion
             ,
             which
             is
             founded
             upon
             the
             experience
             I
             have
             had
             ,
             and
             Observations
             I
             have
             had
             occasion
             to
             make
             on
             that
             Head.
             And
             first
             ,
             I
             find
             in
             all
             these
             Coals
             ,
             wherein
             no
             contrary
             Cropp
             or
             Rising
             could
             be
             visible
             ,
             there
             are
             invincible
             obstructions
             ;
             as
             either
             ,
             they
             have
             been
             near
             the
             Sea
             ,
             and
             have
             dipped
             that
             way
             ;
             and
             so
             if
             they
             took
             any
             contrary
             course
             ,
             the
             cropping
             behoved
             to
             be
             in
             the
             deeps
             ,
             and
             so
             no
             access
             to
             trace
             them
             .
             Or
             next
             ,
             they
             have
             dipped
             towards
             the
             foot
             of
             a
             Mountain
             ,
             and
             so
             the
             ground
             above
             rising
             the
             same
             way
             which
             they
             declined
             ;
             their
             course
             could
             not
             be
             pursued
             ,
             till
             a
             contrary
             rising
             should
             be
             discerned
             .
             Or
             thirdly
             ,
             they
             have
             encountered
             some
             Gae
             ,
             or
             Dyke
             ,
             which
             hath
             cut
             them
             off
             ,
             before
             they
             came
             to
             their
             full
             dipp
             ,
             and
             thus
             their
             course
             was
             obstructed
             .
             Now
             ,
             those
             that
             have
             been
             acquainted
             with
             no
             other
             Coals
             but
             such
             ,
             I
             think
             it
             not
             strange
             ,
             if
             it
             be
             hard
             to
             perswade
             them
             of
             those
             things
             they
             have
             not
             seen
             .
             But
             besides
             all
             those
             kinds
             ,
             I
             have
             seen
             others
             ,
             whose
             contrary
             rising
             and
             dipping
             have
             either
             been
             visible
             to
             the
             eye
             ,
             or
             demonstrable
             by
             reason
             .
             For
             example
             ,
             I
             have
             entered
             under
             ground
             ,
             as
             it
             were
             at
             the
             point
             C
             ,
             at
             the
             very
             Grass-cropp
             ,
             and
             have
             gone
             following
             the
             dipp
             of
             that
             Coal
             to
             the
             point
             B
             ,
             at
             which
             the
             course
             hath
             altered
             ,
             and
             carried
             me
             out
             at
             the
             Grass
             at
             A
             ,
             which
             are
             two
             contrary
             points
             of
             the
             Compass
             .
             And
             that
             alteration
             of
             course
             was
             not
             occasioned
             by
             any
             Gae
             ,
             or
             trouble
             ,
             which
             sometimes
             have
             that
             effect
             ,
             the
             ground
             being
             very
             clean
             ,
             and
             good
             Metals
             ,
             keeping
             their
             course
             most
             regularly
             .
          
           
             There
             are
             other
             instances
             for
             confirming
             my
             experience
             ,
             in
             fields
             ,
             which
             are
             so
             large
             ,
             that
             't
             is
             impossible
             to
             work
             
             the
             Coal
             so
             far
             to
             the
             Dipp
             ,
             it
             falling
             deep
             ,
             and
             so
             wants
             Level
             for
             conveying
             water
             from
             it
             ,
             or
             wants
             Air
             ,
             for
             following
             it
             to
             such
             a
             deepness
             ,
             as
             to
             overtake
             its
             Center
             ,
             where
             it
             takes
             a
             contrary
             course
             ,
             and
             yet
             the
             contrary
             Cropp
             hath
             been
             wrought
             in
             several
             places
             ,
             which
             is
             evident
             to
             be
             a
             part
             of
             the
             same
             body
             ,
             with
             the
             other
             ,
             both
             by
             the
             nature
             of
             the
             Coal
             it self
             ,
             by
             the
             Metals
             lying
             above
             it
             ,
             and
             the
             Coals
             below
             it
             ,
             all
             which
             keeping
             the
             same
             Course
             ,
             except
             when
             they
             encounter
             troubles
             ,
             which
             are
             incident
             to
             some
             parcels
             of
             ground
             ,
             more
             than
             to
             others
             .
             The
             greatest
             field
             I
             know
             wherein
             this
             is
             conspicuous
             ,
             is
             in
             Mid-lothian
             where
             is
             to
             be
             found
             ,
             the
             cropping
             of
             a
             Coal
             of
             a
             considerable
             thickness
             ,
             which
             is
             termed
             their
             great-seam
             ,
             or
             Main-coal
             ,
             and
             the
             other
             Coals
             lying
             below
             it
             ,
             which
             may
             be
             traced
             in
             the
             order
             following
             .
             At
             Preston-Grange
             these
             Coals
             are
             found
             dipping
             to
             the
             N
             W
             ,
             and
             rising
             to
             the
             S
             E
             ,
             which
             have
             been
             wrought
             up
             to
             Wallifoo●d
             :
             from
             that
             along
             by
             the
             foot
             of
             Fa●side
             Hill
             ,
             the
             dipp
             lying
             in
             the
             Lands
             of
             Inneresk
             ,
             which
             marches
             therewith
             on
             the
             North.
             From
             thence
             it
             runs
             through
             the
             ground
             of
             Carberry
             ,
             every
             one
             of
             these
             grounds
             from
             Preston-Grange
             ,
             Giving
             Levell
             to
             another
             .
             From
             thence
             ,
             through
             a
             part
             of
             the
             Lands
             of
             Smeaton
             ,
             and
             next
             through
             a
             piece
             of
             ground
             belonging
             to
             the
             Family
             of
             Buccleugh
             ,
             called
             Coudon
             :
             and
             through
             West-houses
             ,
             which
             belongs
             to
             the
             Earl
             of
             Lothian
             ,
             and
             at
             Cockpen
             ,
             and
             Stobhill
             ,
             from
             thence
             runs
             through
             to
             Carington-Mill
             ;
             all
             which
             is
             a
             course
             ,
             which
             in
             Streek
             lyes
             near
             to
             S
             W
             ,
             and
             N
             W
             ,
             and
             will
             be
             in
             length
             about
             eight
             miles
             .
             From
             thence
             ,
             the
             course
             of
             the
             Coal
             turns
             ,
             and
             is
             found
             in
             the
             Barony
             of
             
               Carington
               ,
               White-hill
               Ramsay
               ,
               Gilmerton
               ,
            
             and
             from
             thence
             taking
             its
             Dipp
             ,
             quite
             contrary
             to
             what
             it
             had
             before
             ,
             the
             other
             Dipping
             N
             and
             N
             W
             ,
             
             or
             N
             E
             ,
             according
             to
             the
             turn
             of
             the
             Streek
             ,
             it
             Dipps
             there
             S
             ,
             S
             E
             ,
             &c.
             and
             from
             Gilmerton
             ,
             it
             is
             found
             at
             Burntstone
             ,
             a
             piece
             of
             ground
             belonging
             to
             the
             Earl
             of
             Lauderdale
             :
             and
             from
             thence
             at
             the
             
               Magdalen
               Pans
            
             ,
             where
             the
             turn
             of
             the
             cropp
             being
             within
             the
             Sea
             ,
             is
             not
             seen
             ,
             till
             it
             be
             found
             at
             Preston-Grange
             ,
             where
             we
             began
             to
             remark
             its
             course
             .
             The
             parcel
             of
             ground
             ,
             under
             which
             this
             great
             body
             of
             Coal
             lyes
             ,
             is
             of
             a
             considerable
             extent
             ,
             it
             being
             eight
             miles
             in
             length
             ,
             and
             five
             or
             six
             in
             breadth
             ;
             in
             regard
             whereof
             many
             other
             Coals
             are
             found
             lying
             above
             the
             great
             Coal
             ,
             the
             cropps
             whereof
             doth
             not
             come
             near
             the
             Cropp
             of
             it
             ,
             by
             a
             considerable
             distance
             .
          
           
             Though
             this
             instance
             alone
             ,
             may
             sufficiently
             convince
             ,
             yet
             I
             shall
             not
             be
             unwilling
             to
             give
             another
             .
             The
             parcel
             of
             ground
             ,
             in
             which
             this
             Coal
             is
             found
             ,
             is
             not
             of
             so
             great
             an
             extent
             ,
             as
             the
             other
             ,
             and
             therefore
             its
             course
             may
             be
             the
             more
             easily
             traced
             .
             For
             the
             greatest
             part
             ,
             it
             belongs
             to
             the
             Earl
             of
             Winton
             ,
             and
             lyes
             within
             the
             
               Lordship
               of
               Tranent
            
             ,
             whose
             contrary
             Cropps
             ,
             are
             most
             conspicuous
             .
             This
             great
             Coal
             ,
             which
             is
             10
             ,
             or
             12
             foot
             thick
             (
             beginning
             at
             the
             head
             of
             the
             Toun
             of
             Tranent
             )
             where
             it
             hath
             been
             wrought
             ,
             runs
             S
             W
             towards
             the
             march
             of
             the
             Lands
             of
             Elphingston
             ,
             belonging
             to
             the
             
               Lord
               Register
            
             ,
             and
             continues
             in
             that
             same
             course
             ,
             till
             it
             come
             near
             to
             the
             house
             ,
             and
             for
             the
             most
             part
             dipping
             to
             the
             S
             E.
             And
             near
             the
             house
             ,
             the
             Cropp
             is
             turned
             downward
             towards
             the
             march
             between
             Elphingston
             and
             Ormiston
             ,
             where
             the
             dipp
             is
             contrary
             to
             the
             former
             .
             And
             from
             Elphingston-mains
             ,
             it
             takes
             its
             course
             almost
             round
             ,
             through
             the
             Lands
             of
             Panston
             ,
             and
             returns
             to
             the
             Toun
             of
             Tranent
             where
             it
             began
             ,
             which
             body
             of
             Coal
             will
             be
             in
             length
             two
             miles
             ,
             and
             in
             some
             places
             ,
             as
             much
             in
             breadth
             .
             Now
             ,
             I
             leave
             it
             to
             the
             judgement
             of
             any
             person
             ,
             if
             there
             be
             
             not
             more
             reason
             to
             perswade
             ,
             that
             this
             should
             be
             the
             natural
             course
             of
             these
             Minerals
             ,
             where
             such
             pregnable
             instances
             ,
             to
             evince
             it
             ,
             are
             found
             ;
             then
             to
             conclude
             the
             contrary
             from
             these
             Coals
             ,
             the
             course
             whereof
             cannot
             be
             followed
             ,
             because
             of
             the
             invincible
             impediments
             ,
             I
             mentioned
             before
             .
             However
             ,
             I
             leave
             every
             one
             to
             be
             determined
             ,
             by
             his
             own
             opinion
             ,
             and
             shall
             be
             satisfied
             to
             injoy
             my
             own
             ,
             till
             these
             of
             more
             experience
             convince
             me
             of
             the
             contrary
             .
          
           
             There
             are
             some
             other
             things
             farder
             to
             be
             remarked
             about
             the
             Dipp
             ,
             and
             Rise
             of
             Coals
             ,
             which
             (
             possibly
             )
             every
             one
             hath
             not
             seen
             ,
             they
             being
             so
             very
             rare
             ,
             and
             therefore
             are
             not
             fit
             here
             to
             be
             passed
             without
             being
             considered
             .
             One
             is
             ,
             of
             a
             Coal
             ,
             which
             having
             that
             contrary
             Dipp
             and
             Rise
             ,
             (
             whereof
             I
             have
             been
             speaking
             )
             in
             one
             of
             the
             cropps
             ,
             hath
             not
             come
             out
             to
             the
             Grass
             ,
             and
             terminat
             ;
             but
             after
             it
             hath
             risen
             a
             considerable
             way
             in
             its
             contrary
             course
             ,
             in
             stead
             of
             Cropping
             out
             ,
             hath
             taken
             a
             Dipp
             towards
             the
             same
             point
             ,
             to
             which
             it
             dipped
             first
             ,
             and
             so
             having
             dipped
             to
             the
             Center
             of
             its
             course
             ,
             it
             hath
             risen
             again
             ,
             and
             cropped
             to
             the
             contrary
             point
             ,
             as
             is
             to
             be
             seen
             in
             this
             eight
             Figure
             .
          
           
             
               Figure
               8.
               
            
          
           
             Where
             A
             B
             is
             the
             surface
             of
             the
             Earth
             .
             The
             point
             B
             is
             the
             Cropp
             of
             a
             
               Coal
               dipping
            
             from
             N
             W
             ,
             to
             the
             S
             E.
             From
             
             C
             it
             takes
             its
             rise
             ,
             and
             course
             to
             a
             contrary
             Cropp
             ,
             towards
             the
             point
             F
             ,
             where
             the
             
               dead
               Cropp
            
             ought
             to
             be
             found
             .
             But
             in
             stead
             of
             going
             that
             length
             ,
             it
             takes
             another
             course
             from
             the
             point
             E
             ,
             dipping
             S
             E
             towards
             D
             ,
             from
             which
             it
             takes
             its
             rise
             ,
             and
             continues
             it
             to
             the
             point
             A
             ,
             where
             it
             terminats
             ,
             and
             where
             the
             
               dead
               Cropp
            
             is
             found
             .
             I
             grant
             ,
             that
             it
             meets
             with
             a
             trouble
             ,
             or
             Gae
             ,
             at
             the
             point
             E
             ,
             which
             seems
             to
             be
             the
             cause
             ,
             why
             its
             natural
             course
             is
             changed
             .
             But
             it
             s
             very
             extraordinary
             to
             see
             such
             an
             effect
             .
             But
             of
             this
             afterwards
             ,
             in
             its
             own
             place
             .
          
           
             There
             is
             yet
             another
             thing
             to
             be
             remarked
             ,
             in
             the
             dipps
             ,
             and
             risings
             of
             Coals
             ,
             which
             is
             this
             .
             In
             the
             most
             part
             of
             Coals
             ,
             that
             have
             their
             course
             from
             dipp
             to
             cropp
             ,
             without
             the
             intervention
             of
             a
             
               dyke
               or
               gae
            
             ,
             the
             declination
             is
             straight
             down
             ,
             from
             the
             horizontal
             line
             drawn
             from
             the
             point
             of
             the
             cropp
             ,
             to
             the
             fardest
             point
             of
             the
             dipp
             .
             That
             is
             ,
             the
             Coal
             declining
             from
             that
             point
             in
             a
             right
             line
             ,
             makes
             with
             the
             horizontal
             line
             ,
             a
             
               right
               lined
               angle
               ,
               angulus
               rectilineus
               ,
            
             though
             in
             some
             the
             angle
             is
             more
             acute
             ,
             and
             in
             others
             less
             ,
             as
             is
             to
             be
             seen
             in
             the
             first
             ,
             and
             second
             figures
             ,
             where
             A
             B
             being
             the
             horizontal
             Line
             ,
             and
             B
             the
             cropp
             ,
             B
             C
             is
             the
             body
             of
             the
             Coal
             declining
             ,
             which
             meeting
             with
             A
             B
             in
             the
             point
             B
             ,
             constitutes
             a
             
               right
               lined
               angle
            
             ,
             and
             where
             A
             B
             C
             in
             the
             second
             figure
             ,
             is
             a
             greater
             angle
             ,
             then
             A
             B
             C
             in
             the
             first
             .
             Yet
             I
             have
             seen
             a
             Coal
             ,
             the
             body
             whereof
             from
             the
             dipp
             ,
             or
             fardest
             point
             of
             declination
             ,
             had
             its
             rise
             towards
             the
             cropp
             very
             insensibly
             ,
             it
             being
             Flatt
             ,
             and
             then
             began
             to
             be
             more
             sensible
             ,
             till
             at
             last
             coming
             near
             to
             the
             surface
             of
             the
             Earth
             ,
             it
             takes
             in
             a
             sudden
             such
             a
             rise
             ,
             that
             from
             declining
             one
             foot
             of
             12
             or
             14
             ,
             it
             declines
             now
             one
             foot
             of
             three
             ,
             as
             may
             be
             made
             evident
             from
             this
             following
             Figure
             .
          
           
             
               Figure
               9.
               
            
          
           
             Where
             A
             B
             is
             the
             Line
             drawn
             from
             the
             extream
             points
             of
             the
             Cropp
             ,
             right
             horizontal
             .
             The
             body
             of
             the
             
               Coal
               rising
            
             insensibly
             ,
             is
             D
             C.
             But
             assoon
             as
             it
             comes
             to
             C
             ,
             it
             riseth
             with
             a
             great
             ascent
             till
             it
             Cropp
             out
             at
             A.
             Here
             you
             see
             ,
             that
             in
             stead
             of
             one
             side
             of
             a
             Triangle
             ,
             which
             the
             course
             of
             other
             Coals
             in
             their
             rising
             ,
             or
             in
             their
             declination
             makes
             ;
             this
             Coal
             in
             rising
             makes
             two
             sides
             ,
             namely
             D
             C
             ,
             and
             C
             A
             ,
             the
             Figure
             D
             B
             C
             A
             being
             quadrilateral
             .
             The
             Coal
             of
             this
             course
             was
             really
             wrought
             ,
             and
             is
             yet
             visible
             in
             its
             waste
             ,
             where
             there
             is
             found
             no
             Gae
             or
             Dyke
             to
             make
             this
             alteration
             .
          
           
             These
             are
             the
             chief
             things
             that
             I
             have
             thought
             worthy
             of
             Observation
             in
             the
             Dipps
             ,
             and
             Risings
             of
             Coals
             ,
             and
             therefore
             I
             come
             now
             to
             touch
             a
             little
             the
             other
             part
             of
             their
             course
             ,
             which
             is
             commonly
             termed
             the
             Streek
             of
             a
             Coal
             .
             To
             make
             intelligible
             to
             those
             ,
             who
             are
             not
             experimentally
             acquainted
             with
             Coal
             ,
             this
             term
             ,
             or
             what
             the
             Streek
             is
             ,
             we
             must
             lay
             this
             foundation
             ,
             that
             the
             Coal
             is
             a
             
               Physical
               Body
            
             ,
             and
             so
             hath
             its
             three
             principal
             dimensions
             ,
             which
             do
             constitute
             it
             so
             ,
             
               viz
               ,
               Longitude
               ,
               Latitude
            
             ,
             and
             ●rofundity
             .
             '
             Its
             Latitude
             ,
             is
             that
             part
             contained
             between
             its
             extream
             lines
             ,
             which
             is
             measurable
             by
             its
             surface
             ,
             to
             which
             
             its
             dipping
             and
             rising
             ,
             though
             alwayes
             incident
             ,
             yet
             is
             but
             accidental
             .
             It
             s
             Profundity
             is
             to
             be
             measured
             by
             the
             distance
             ,
             between
             the
             two
             surfaces
             ,
             immediately
             next
             to
             it
             ,
             above
             and
             below
             :
             which
             are
             termed
             in
             Coallery
             its
             Roof
             and
             Pavement
             ,
             because
             of
             the
             resemblance
             they
             have
             to
             the
             Roof
             ,
             and
             Pavement
             of
             a
             house
             .
             The
             Longitude
             is
             nothing
             else
             but
             what
             is
             termed
             by
             the
             Coal-hewers
             ,
             the
             Streek
             .
             For
             if
             you
             imagine
             a
             Line
             drawn
             along
             the
             extream
             points
             of
             the
             Rise
             ,
             or
             Cropp
             of
             the
             Coal
             ,
             that
             is
             properly
             the
             Streek
             of
             the
             Coal
             .
          
           
             There
             are
             but
             few
             things
             to
             be
             remarked
             ,
             as
             to
             this
             part
             of
             Coal
             :
             only
             first
             to
             find
             how
             it
             lyes
             ,
             to
             what
             points
             of
             the
             Compass
             it
             moves
             .
             For
             knowing
             whereof
             ,
             there
             is
             this
             general
             Rule
             ,
             that
             ,
             having
             found
             your
             Dipp
             and
             Rise
             ,
             to
             what
             ever
             Points
             that
             Course
             is
             directed
             ,
             the
             Streek
             is
             to
             the
             quite
             contrary
             .
             For
             supposing
             a
             
               Coal
               Dipp
            
             S
             E
             ,
             the
             two
             points
             ,
             that
             respect
             the
             Dipp
             and
             Rise
             ,
             must
             be
             S
             E
             ,
             and
             N
             W
             ,
             being
             the
             points
             opposite
             one
             to
             another
             .
             Then
             it
             must
             needs
             follow
             ,
             that
             the
             Streek
             must
             run
             S
             W
             ,
             and
             N
             E
             ,
             which
             two
             courses
             divides
             the
             Compass
             ,
             at
             
               right
               Angles
            
             .
             And
             therefore
             ,
             where
             a
             Coal
             is
             found
             to
             have
             contrary
             Dipps
             ,
             and
             Risings
             ,
             they
             declining
             sometimes
             to
             all
             the
             Points
             of
             the
             Compass
             (
             whereof
             there
             hath
             been
             given
             two
             notable
             instances
             before
             )
             it
             must
             needs
             follow
             ,
             that
             there
             be
             also
             contrary
             Streeks
             ,
             and
             so
             the
             Streek
             of
             a
             Body
             of
             Coal
             is
             sometimes
             found
             to
             describe
             a
             round
             figure
             ,
             though
             not
             perfectly
             circular
             ,
             and
             somtimes
             a
             multangular
             figure
             .
             For
             it
             cannot
             be
             supposed
             that
             the
             Streek
             makes
             alwayes
             a
             right
             Line
             ,
             between
             the
             two
             points
             ,
             from
             which
             it
             is
             reckoned
             .
             For
             example
             ,
             between
             the
             Laird
             of
             Preston-grange
             his
             house
             at
             Preston-pans
             ,
             and
             the
             Stob-hill
             ,
             there
             are
             the
             Streeks
             of
             several
             Coals
             ,
             lying
             one
             above
             
             another
             ,
             which
             will
             be
             of
             length
             ,
             about
             seven
             or
             eight
             miles
             ,
             lying
             near
             upon
             S
             W
             ,
             and
             N
             E
             ;
             yet
             the
             Cropps
             of
             the
             said
             Coals
             (
             their
             dipp
             ,
             and
             rise
             ,
             being
             N
             W
             ,
             and
             S
             E
             )
             are
             sometimes
             farder
             advanced
             towards
             the
             S
             E
             ,
             sometimes
             farder
             back
             towards
             the
             N
             W
             ,
             by
             the
             difference
             of
             a
             mile
             ,
             and
             this
             generally
             occasioned
             by
             the
             encounter
             of
             a
             Dyke
             or
             Gae
             ,
             whereof
             hereafter
             .
          
           
             The
             same
             question
             ,
             that
             occurred
             in
             the
             
               Coals
               dipping
            
             towards
             a
             Hill
             ,
             or
             rising
             above
             ground
             ,
             comes
             to
             be
             inquired
             into
             here
             ;
             viz.
             If
             a
             Coal
             encountering
             an
             ascent
             ,
             or
             Brae
             above
             ground
             in
             its
             Streek
             ,
             rises
             also
             with
             the
             ground
             ,
             and
             keeps
             its
             ascent
             ?
             I
             answer
             ,
             I
             have
             found
             it
             so
             in
             all
             the
             Coals
             I
             have
             ever
             seen
             of
             that
             nature
             .
             GOD
             in
             his
             providence
             ,
             having
             so
             ordered
             it
             ,
             that
             thereby
             it
             may
             be
             the
             more
             useful
             ,
             in
             regard
             more
             thereof
             may
             be
             wrought
             by
             one
             Level
             or
             Aquaeduct
             ,
             by
             which
             the
             Water
             is
             conveyed
             away
             ,
             as
             afterwards
             will
             be
             observed
             in
             speaking
             to
             Levels
             .
             For
             confirmation
             whereof
             ,
             I
             shall
             bring
             instances
             both
             of
             Coals
             ,
             that
             declines
             towards
             the
             Hill
             ,
             and
             of
             others
             that
             declines
             with
             the
             same
             dipp
             ,
             the
             Hill
             hath
             it self
             .
             In
             the
             Coals
             of
             
               B●nhard
               ,
               Grange
               ,
               Kinglassy
            
             ,
             and
             Kinneil
             ,
             which
             keep
             all
             one
             general
             course
             ,
             the
             ascent
             above
             ground
             is
             from
             the
             Sea
             ,
             (
             which
             lyes
             North
             )
             towards
             the
             South
             ,
             or
             thereabout
             ;
             the
             
               Coal
               dipps
            
             or
             declines
             towards
             the
             N
             W
             ,
             and
             so
             consequently
             rises
             to
             the
             S
             E.
             The
             Streek
             of
             these
             Coals
             ,
             is
             from
             the
             N
             E
             to
             S
             W
             ,
             which
             slops
             alongs
             the
             Hill
             ,
             and
             comes
             up
             to
             the
             top
             thereof
             to
             the
             Westward
             of
             the
             House
             of
             B●nhard
             .
             Now
             ,
             in
             sinking
             in
             that
             ground
             ,
             if
             an
             equal
             proportion
             be
             kept
             ,
             in
             all
             the
             Sinks
             from
             the
             Cropp
             ,
             and
             a
             just
             allowance
             given
             for
             the
             different
             Rising
             above
             ground
             ,
             the
             Sinks
             will
             be
             near
             of
             an
             equal
             deepness
             along
             all
             the
             Streek
             .
             So
             that
             a
             Sink
             upon
             the
             
             same
             Coal
             near
             to
             the
             Sea
             ,
             which
             is
             the
             N
             E
             point
             of
             the
             Streek
             ,
             at
             equal
             distance
             from
             the
             Cropp
             ,
             will
             be
             as
             deep
             as
             a
             Sink
             upon
             the
             top
             of
             the
             Hill
             ,
             being
             the
             S
             W
             point
             of
             the
             Streek
             at
             the
             same
             distance
             from
             the
             Cropp
             ,
             allowing
             alwayes
             the
             different
             rise
             above
             ground
             ,
             and
             excepting
             some
             particular
             troubles
             falling
             in
             upon
             the
             Metals
             of
             one
             Sink
             ,
             and
             not
             of
             another
             ,
             and
             so
             making
             them
             dipp
             more
             ,
             which
             will
             occasion
             a
             difference
             of
             the
             deepness
             .
             The
             same
             is
             also
             found
             in
             the
             Coals
             of
             Dysart
             ,
             and
             Weems
             .
             As
             also
             in
             that
             great
             body
             of
             Coal
             before
             mentioned
             ,
             between
             Preston-grange
             and
             Stobhill
             ,
             the
             declination
             whereof
             is
             to
             the
             N
             E
             ,
             which
             is
             also
             the
             course
             of
             the
             descent
             above
             ground
             .
          
           
             Another
             instance
             is
             from
             the
             Coals
             within
             the
             Lordship
             of
             Tranent
             ,
             the
             dipp
             whereof
             is
             of
             another
             course
             ,
             being
             contrary
             to
             the
             descent
             of
             the
             Hill
             ,
             viz.
             the
             
               Coal
               dipping
            
             to
             the
             S
             E
             ,
             and
             consequently
             the
             Streek
             running
             S
             W
             ,
             and
             N
             E
             ,
             where
             the
             same
             is
             to
             be
             observed
             that
             was
             seen
             in
             the
             other
             ,
             anent
             the
             equality
             of
             the
             deepness
             of
             Sinks
             along
             the
             Streek
             ,
             with
             the
             same
             allowances
             ,
             and
             exceptions
             before
             mentioned
             .
          
           
             Some
             have
             been
             of
             opinion
             that
             Streeks
             of
             Coals
             ly
             generally
             South
             and
             North
             ,
             or
             to
             some
             of
             the
             points
             near
             to
             these
             two
             Cardinal
             ones
             ,
             between
             South
             and
             S
             W
             ,
             and
             North
             and
             N
             E
             ,
             as
             South
             and
             by
             West
             ,
             and
             North
             and
             by
             East
             ,
             &c.
             
             To
             which
             general
             I
             cannot
             agree
             ,
             in
             regard
             of
             what
             I
             have
             before
             made
             evidently
             appear
             ,
             viz.
             that
             some
             Coals
             have
             their
             croppings
             towards
             all
             the
             points
             of
             the
             Compass
             ,
             and
             the
             Streeks
             being
             regulated
             by
             the
             Cropps
             ,
             they
             must
             necessarily
             be
             judged
             to
             have
             their
             courses
             proportioned
             to
             theirs
             :
             so
             that
             if
             a
             
               Coal
               dipp
            
             to
             the
             true
             North
             ,
             and
             rise
             to
             the
             South
             ,
             the
             Streek
             must
             be
             East
             ,
             and
             
             West
             .
             However
             ,
             I
             acknowledge
             two
             things
             ,
             for
             confirming
             that
             opinion
             .
          
           
             First
             ,
             that
             of
             all
             the
             Coals
             I
             ever
             have
             seen
             ,
             where
             these
             contrary
             dipps
             and
             risings
             ,
             could
             not
             be
             traced
             ,
             and
             made
             visible
             ,
             the
             Sreek
             hath
             inclined
             to
             those
             points
             of
             South
             and
             North.
             But
             I
             must
             also
             confess
             ,
             that
             they
             are
             but
             few
             I
             have
             seen
             ,
             in
             respect
             of
             what
             I
             have
             not
             seen
             ,
             and
             so
             if
             any
             others
             experience
             ,
             who
             have
             seen
             more
             ,
             contradict
             mine
             ,
             I
             shall
             willingly
             yeeld
             ,
             and
             not
             be
             tenacious
             .
          
           
             Next
             ,
             in
             these
             Coals
             ,
             which
             I
             instanced
             ,
             that
             have
             their
             Cropp
             to
             all
             the
             Points
             ,
             and
             consequently
             their
             Streeks
             ,
             and
             in
             others
             of
             the
             same
             nature
             ,
             which
             I
             have
             seen
             ,
             and
             not
             instanced
             ,
             I
             found
             that
             part
             of
             the
             Streek
             ,
             which
             lyes
             towards
             these
             
               Cardinal
               points
            
             ,
             to
             be
             the
             greatest
             ,
             being
             double
             ,
             or
             triple
             to
             the
             other
             Sreeks
             in
             length
             .
             So
             that
             when
             the
             Streek
             ,
             that
             lyes
             either
             along
             the
             one
             Cropp
             ,
             or
             the
             other
             ,
             towards
             the
             S
             W
             ,
             and
             N
             E
             ,
             will
             be
             seven
             miles
             in
             length
             ,
             that
             lying
             S
             E
             ,
             and
             N
             W
             ,
             will
             be
             but
             four
             ,
             and
             sometimes
             less
             .
             And
             this
             is
             all
             the
             account
             I
             can
             give
             ,
             of
             that
             part
             of
             Coal
             ,
             called
             the
             Streek
             .
          
           
             The
             second
             thing
             I
             promised
             to
             speak
             of
             ,
             was
             of
             some
             things
             ,
             which
             are
             but
             accidental
             to
             Coals
             ,
             and
             yet
             so
             ordinary
             ,
             that
             hardly
             are
             any
             found
             without
             them
             in
             lesser
             ,
             or
             greater
             degree
             ,
             such
             are
             Gae's
             ,
             and
             Dykes
             ,
             which
             alters
             their
             natural
             course
             ,
             and
             they
             being
             the
             occasion
             of
             so
             much
             Trouble
             ,
             in
             the
             working
             of
             Coal
             ,
             and
             following
             its
             course
             ,
             the
             Coal-hewers
             call
             them
             ordinarily
             by●that
             name
             Trouble
             .
             This
             Trouble
             or
             Gae
             then
             ,
             is
             a
             Body
             of
             
             Metal-falling
             in
             upon
             the
             course
             of
             the
             Coal
             ,
             or
             Free-stone
             ,
             obstructing
             ,
             or
             altering
             their
             kindly
             and
             natural
             course
             ,
             keeping
             no
             regular
             course
             it self
             ,
             and
             being
             of
             nature
             alwayes
             different
             from
             the
             Metal
             ,
             whose
             course
             it
             interrupts
             .
             And
             these
             Gae's
             differ
             
             also
             among
             themselves
             ,
             in
             their
             nature
             ,
             and
             in
             their
             course
             they
             keep
             :
             or
             more
             properly
             in
             the
             way
             wherein
             they
             encounter
             other
             Metalls
             ,
             and
             in
             their
             effects
             .
             In
             their
             nature
             ,
             for
             some
             of
             them
             con●ists
             of
             an
             impregnable
             Whin-Rock
             ,
             or
             Flinty-Stone
             ,
             thorow
             which
             it
             is
             almost
             impossible
             to
             work
             :
             and
             if
             there
             be
             a
             necessity
             to
             cut
             them
             thorow
             ,
             it
             is
             done
             at
             a
             vast
             expence
             ,
             and
             takes
             a
             long
             time
             ,
             and
             must
             be
             cut
             open
             to
             the
             surface
             of
             the
             earth
             ,
             it
             being
             impossible
             to
             Mine
             it
             under
             ground
             .
             Some
             of
             them
             are
             again
             of
             Stone
             ,
             like
             a
             Free-stone
             ,
             but
             seems
             rather
             an
             abortive
             of
             nature
             ,
             they
             having
             no
             rule
             in
             their
             course
             ,
             by
             which
             a
             man
             can
             follow
             them
             ,
             nor
             can
             their
             stone
             be
             useful
             .
          
           
             In
             their
             encountering
             of
             Coals
             ,
             or
             Free-stone
             ,
             sometimes
             they
             encounter
             them
             in
             the
             Dip
             ,
             and
             sometimes
             in
             the
             Streek
             ,
             and
             sometimes
             between
             the
             two
             .
             These
             that
             are
             met
             with
             in
             following
             the
             Dipp
             of
             the
             Coal
             ,
             ly
             along
             the
             Streek
             thereof
             .
             For
             example
             ,
             if
             the
             
               Coal
               Dipp
            
             S
             E
             ,
             the
             Gae
             lies
             N
             E
             ,
             and
             S
             W.
             These
             that
             are
             encountered
             in
             the
             Streek
             ,
             lyes
             to
             the
             Dipp
             and
             Rise
             :
             so
             the
             
               Coal
               Streeking
            
             N
             E
             ,
             and
             S
             W
             ,
             the
             Gae
             is
             found
             to
             ly
             S
             E
             ,
             and
             N
             W.
             Others
             of
             them
             ,
             lyes
             between
             Streek
             and
             Dipp
             ,
             that
             is
             to
             some
             point
             between
             the
             two
             :
             as
             the
             Streek
             being
             S
             W
             ,
             and
             N
             E
             ,
             and
             the
             Dipp
             and
             Rise
             S
             E
             ,
             and
             N
             W
             ,
             there
             may
             be
             a
             Gae
             found
             lying
             W
             S
             W
             ,
             and
             E
             N
             E.
             Now
             ,
             when
             I
             speak
             of
             a
             Gae's
             lying
             to
             such
             Points
             of
             the
             Compass
             ,
             this
             doth
             not
             contradict
             what
             was
             said
             before
             ,
             that
             they
             had
             no
             regular
             course
             themselves
             .
             My
             meaning
             being
             ,
             that
             though
             they
             have
             a
             certain
             length
             ,
             lying
             between
             two
             points
             ,
             and
             a
             thickness
             between
             two
             Metalls
             ,
             yet
             by
             the
             Metal
             of
             the
             Gae
             it self
             ,
             it
             is
             impossible
             to
             know
             its
             course
             ,
             as
             it
             is
             in
             other
             Metalls
             of
             Coal
             or
             Free-stone
             ,
             whose
             courses
             are
             discernable
             at
             the
             first
             view
             .
          
           
           
             Their
             effects
             are
             different
             ,
             as
             their
             nature
             and
             course
             are
             different
             :
             only
             they
             agree
             in
             these
             two
             generals
             .
             First
             ,
             that
             all
             of
             them
             renders
             that
             part
             of
             the
             Coal
             ,
             that
             comes
             nearest
             to
             them
             ,
             unprofitable
             and
             useless
             ,
             though
             some
             less
             ,
             and
             some
             more
             ,
             they
             being
             unfit
             for
             burning
             .
             And
             it
             is
             remarked
             ,
             that
             these
             Gaes
             that
             consists
             of
             Whin-rock
             ,
             renders
             the
             Coal
             next
             to
             it
             ,
             as
             if
             it
             were
             already
             burnt
             ,
             being
             so
             dried
             ,
             that
             it
             moulders
             in
             handling
             it
             .
             In
             others
             ,
             the
             Coal
             is
             not
             altogether
             so
             ill
             ,
             and
             yet
             its
             nature
             is
             altered
             ,
             from
             what
             it
             is
             at
             a
             distance
             from
             the
             Gae
             .
             The
             next
             general
             is
             ,
             that
             all
             of
             them
             alters
             the
             natural
             course
             of
             the
             Coal
             in
             less
             or
             more
             ,
             some
             of
             them
             making
             it
             Dipp
             much
             more
             then
             its
             ordinary
             course
             ,
             which
             they
             call
             Down-gaes
             :
             Some
             again
             making
             their
             rise
             much
             more
             than
             their
             course
             ,
             which
             they
             call
             Up-gaes
             .
             Others
             making
             an
             alteration
             as
             to
             the
             Streek
             ,
             causing
             it
             go
             out
             beyond
             its
             ordinary
             bounds
             ,
             as
             we
             observed
             before
             in
             that
             great
             Streek
             of
             Coal
             between
             Preston-Grange
             and
             Stobhill
             .
          
           
             Now
             it
             is
             to
             be
             considered
             ,
             that
             when
             in
             working
             of
             a
             Coal
             ,
             whether
             to
             the
             Dipp
             ,
             or
             Rise
             ,
             or
             Streek
             ,
             one
             of
             these
             Gaes
             is
             encountered
             with
             ,
             the
             Coal
             is
             quite
             cut
             off
             ,
             and
             as
             it
             were
             terminat
             :
             so
             that
             you
             see
             nothing
             where
             the
             Coal
             should
             be
             ,
             but
             either
             a
             Stone
             ,
             or
             Clay
             ,
             or
             rotten
             Till
             ,
             or
             some
             such
             thing
             .
             And
             the
             practique
             of
             Coallery
             is
             to
             trace
             the
             course
             of
             the
             Coal
             through
             that
             ,
             till
             you
             overtake
             it
             in
             the
             other
             side
             .
             And
             before
             any
             thing
             be
             said
             to
             that
             part
             ,
             you
             must
             notice
             ,
             that
             some
             Gaes
             are
             of
             greater
             force
             than
             others
             ,
             and
             their
             influence
             upon
             the
             course
             of
             other
             Metalls
             greater
             ,
             whence
             you
             shall
             see
             a
             threefold
             effect
             .
             One
             is
             ,
             that
             by
             some
             great
             Gaes
             ,
             which
             a
             Coal
             meets
             with
             〈◊〉
             is
             quite
             cut
             off
             ,
             so
             that
             in
             the
             other
             side
             thereof
             ,
             there
             〈◊〉
             not
             a
             vestige
             of
             that
             Coal
             ,
             or
             of
             any
             other
             Metal
             that
             wa●
             
             above
             it
             ,
             or
             below
             it
             ,
             to
             be
             seen
             .
             And
             if
             there
             be
             any
             other
             Coal
             ,
             as
             sometimes
             there
             are
             ,
             they
             are
             quite
             different
             from
             them
             of
             the
             other
             side
             .
             I
             said
             by
             some
             ,
             because
             there
             is
             one
             instance
             to
             the
             contrary
             ,
             which
             is
             somewhat
             singular
             .
             In
             the
             Earl
             of
             
             Winton's
             ground
             at
             Cockeny
             ,
             there
             is
             found
             a
             course
             of
             Coals
             and
             
               Free-stone
               ,
               dipping
            
             to
             the
             S
             E
             in
             the
             Links
             ;
             and
             upon
             the
             full-sea-mark
             ,
             there
             is
             a
             tract
             or
             course
             of
             Whin-rocks
             lying
             E
             and
             W
             ,
             underneath
             which
             these
             Coals
             and
             Stones
             comes
             thorow
             without
             alteration
             of
             course
             ,
             and
             are
             found
             I
             within
             the
             Sea-mark
             ,
             with
             the
             same
             Dipp
             and
             Rise
             upon
             the
             North
             side
             ,
             they
             had
             upon
             the
             South
             side
             of
             the
             said
             Rocks
             :
             and
             yet
             the
             Coal
             is
             encountered
             upon
             the
             South
             hand
             by
             a
             Gae
             under
             ground
             ,
             through
             which
             it
             passeth
             ,
             not
             without
             a
             considerable
             alteration
             .
          
           
             The
             greatest
             of
             these
             Gaes
             ,
             that
             I
             know
             ,
             is
             that
             which
             takes
             its
             beginning
             ,
             that
             we
             see
             on
             Land
             ,
             at
             the
             Harbour
             of
             the
             Pans
             ,
             called
             Achisons-Haven
             ,
             which
             hath
             been
             cut
             by
             Preston-Grange
             ,
             for
             Level
             to
             his
             Coal
             ,
             and
             goes
             from
             that
             to
             Seton
             ,
             which
             may
             be
             traced
             above
             ground
             ,
             almost
             the
             whole
             way
             ;
             and
             hath
             been
             cut
             at
             Seton
             ;
             for
             serving
             the
             Level
             of
             that
             Coal
             now
             wrought
             at
             Tranent
             .
             From
             thence
             it
             passeth
             through
             the
             fields
             of
             Long-Niddry
             ,
             a
             place
             pertaining
             to
             the
             Earl
             of
             Winton
             ,
             and
             through
             the
             Coats
             ,
             which
             pertains
             to
             the
             Earl
             of
             Hadington
             ,
             till
             it
             joyn
             with
             Pancreck-hills
             ,
             a
             tract
             of
             Rocky
             Mountains
             ,
             from
             whence
             it
             is
             traceable
             to
             Linton-bridges
             ,
             where
             it
             is
             visible
             in
             the
             Water
             ,
             the
             Water
             of
             Tyn
             falling
             over
             it
             ,
             and
             making
             a
             Lin
             ,
             which
             they
             call
             Linton-Lin
             ;
             from
             thence
             to
             the
             East-sea
             .
             And
             it
             is
             known
             by
             Sea-men
             ,
             that
             it
             keeps
             a
             course
             thorow
             the
             Firth
             from
             Achisons-haven
             ,
             (
             whence
             we
             reckoned
             its
             beginning
             upon
             Land
             )
             towards
             the
             West
             
             and
             N
             W
             ,
             it
             being
             found
             to
             the
             Southward
             of
             Inch-keith
             ,
             and
             before
             Leith
             ,
             where
             stands
             a
             Beacon
             ,
             and
             so
             can
             be
             traced
             to
             the
             North
             Shore
             .
          
           
             The
             second
             effect
             of
             Gaes
             ,
             is
             to
             cut
             off
             the
             Coal
             quite
             ,
             as
             to
             a
             part
             of
             the
             field
             ,
             so
             that
             in
             the
             other
             side
             ,
             having
             pierced
             the
             Gae
             ,
             you
             shall
             not
             find
             the
             Coal
             ,
             and
             possibly
             not
             within
             a
             quarter
             of
             a
             mile
             of
             the
             Gae
             ,
             which
             cuts
             it
             off
             ,
             and
             at
             that
             place
             shall
             only
             find
             the
             Cropp
             and
             the
             Body
             Dipping
             ,
             as
             it
             did
             before
             it
             was
             cut
             off
             ;
             and
             if
             you
             shall
             measure
             between
             that
             side
             of
             the
             Gae
             ,
             where
             you
             lost
             your
             Coal
             (
             I
             suppose
             the
             Coal
             then
             being
             24
             fathom
             from
             the
             Grass
             )
             to
             the
             place
             where
             the
             Coal
             in
             the
             other
             side
             of
             the
             Gae
             shall
             be
             found
             at
             the
             same
             deepness
             ,
             it
             will
             be
             near
             500
             paces
             .
             For
             making
             this
             more
             intelligible
             ,
             let
             us
             suppose
             a
             
               Coal
               Dipping
            
             S
             E
             ,
             and
             in
             working
             to
             the
             Dipp
             ,
             there
             is
             a
             Gae
             encountered
             with
             (
             This
             was
             really
             done
             in
             a
             piece
             of
             ground
             I
             know
             ,
             and
             so
             it
             is
             no
             meer
             supposition
             )
             at
             which
             Gae
             the
             Coal
             is
             cut
             off
             ;
             for
             finding
             whereof
             the
             Gae
             is
             pierced
             ,
             and
             nothing
             found
             in
             the
             other
             side
             ,
             viz.
             in
             the
             S
             E
             side
             of
             the
             Gae
             ,
             but
             at
             more
             than
             100
             paees
             distant
             ,
             the
             Crop
             of
             a
             Coal
             ,
             which
             lyes
             under
             the
             Coal
             ,
             that
             was
             lost
             ,
             was
             found
             ,
             after
             which
             it
             was
             easie
             to
             find
             the
             other
             .
             Now
             ,
             that
             it
             was
             the
             same
             Coal
             ,
             that
             was
             lost
             ,
             upon
             the
             North
             side
             of
             the
             Gae
             ,
             is
             not
             only
             evident
             ,
             by
             the
             kind
             of
             Coal
             ,
             and
             all
             the
             Metals
             above
             ,
             and
             below
             keeping
             the
             same
             course
             ,
             but
             by
             this
             ,
             that
             the
             Gae
             wearing
             out
             towards
             the
             West
             ,
             the
             two
             parts
             of
             the
             Coal
             that
             was
             separated
             by
             it
             ,
             joynes
             themselves
             again
             ,
             and
             continues
             in
             one
             body
             ,
             as
             they
             were
             before
             separation
             .
          
           
             The
             last
             effect
             of
             the
             Gae
             is
             ,
             that
             it
             doth
             not
             quite
             cut
             off
             the
             Coal
             from
             the
             other
             side
             of
             it
             ,
             but
             makes
             an
             alteration
             in
             the
             course
             ,
             either
             in
             the
             Dipp
             ,
             or
             in
             the
             Rise
             ,
             or
             
             Streek
             ,
             as
             was
             before
             noted
             :
             so
             that
             in
             meeting
             with
             one
             of
             these
             Gaes
             ,
             having
             considered
             its
             nature
             ,
             and
             pierced
             it
             ,
             the
             Coal
             will
             be
             found
             in
             the
             other
             side
             ,
             immediatly
             touching
             the
             Gae
             ,
             but
             with
             an
             alteration
             of
             course
             .
             Now
             ,
             in
             these
             two
             last
             effects
             ,
             since
             the
             Coal
             is
             not
             totally
             cut
             off
             ,
             it
             will
             be
             worth
             the
             inquiry
             ,
             to
             find
             the
             surest
             way
             of
             recovering
             the
             Coal
             after
             it
             is
             lost
             .
             Therefore
             ,
             where
             the
             Coal
             is
             not
             cut
             off
             ,
             by
             a
             considerable
             distance
             ,
             and
             having
             pierced
             the
             Gae
             ,
             it
             is
             not
             to
             be
             found
             in
             the
             other
             side
             ,
             you
             are
             to
             consider
             well
             the
             nature
             of
             the
             Metals
             you
             find
             approach
             to
             the
             Gae
             ,
             and
             if
             they
             be
             such
             ,
             whether
             Stone
             ,
             or
             Coal
             ,
             as
             you
             know
             to
             ly
             under
             the
             Coal
             that
             you
             have
             lost
             ,
             then
             you
             may
             be
             sure
             the
             Coal
             is
             to
             be
             found
             above
             in
             its
             course
             ,
             which
             is
             to
             be
             traced
             by
             the
             Dipp
             of
             the
             Metals
             you
             find
             .
             As
             sometimes
             I
             have
             seen
             ,
             when
             a
             Coal
             hath
             been
             cut
             off
             by
             a
             Gae
             ,
             happly
             there
             is
             another
             Coal
             under
             it
             12
             fathom
             ,
             after
             the
             Gae
             hath
             been
             pierced
             ,
             and
             the
             lost
             Coal
             not
             coming
             near
             to
             it
             in
             the
             other
             side
             ,
             that
             hath
             been
             found
             there
             ,
             by
             which
             it
             was
             certainly
             concluded
             ,
             that
             the
             uppermost
             Coal
             behoved
             to
             be
             there
             also
             ,
             though
             a
             little
             back
             ,
             conform
             to
             its
             course
             .
             But
             ,
             if
             the
             Metals
             or
             Coals
             ,
             under
             the
             lost
             Coal
             ,
             hath
             not
             been
             known
             ,
             then
             you
             are
             to
             take
             notice
             of
             the
             Dipp
             and
             Rise
             of
             these
             Metals
             ,
             you
             find
             on
             the
             other
             side
             of
             the
             Gae
             ,
             which
             you
             have
             pierced
             ,
             and
             making
             that
             your
             rule
             ,
             
               range
               back
               over
               the
               Metals
            
             ,
             conform
             to
             the
             direction
             to
             be
             given
             afterwards
             ,
             and
             you
             shall
             find
             the
             Cropp
             of
             the
             Coal
             you
             want
             ,
             and
             after
             which
             you
             were
             inquiring
             .
          
           
             Where
             the
             Coal
             is
             not
             quite
             cut
             off
             by
             the
             Gae
             ,
             but
             hath
             its
             course
             only
             altered
             ,
             you
             are
             to
             consider
             ,
             in
             searching
             for
             it
             ,
             before
             you
             pierce
             your
             Gae
             ,
             that
             which
             the
             Coal-hewers
             term
             the
             Vise
             ,
             or
             some
             of
             them
             the
             Weyse
             of
             the
             Gae
             ,
             
             which
             in
             effect
             is
             nothing
             else
             ,
             but
             a
             dark
             vestige
             of
             the
             Dipp
             or
             Rise
             ,
             that
             the
             body
             which
             now
             constitutes
             the
             Gae
             ,
             should
             have
             had
             naturally
             ,
             if
             it
             had
             been
             perfected
             ;
             which
             when
             it
             tends
             downward
             ,
             then
             must
             the
             Gae
             be
             put
             over
             that
             way
             ,
             and
             in
             the
             other
             side
             shall
             the
             Coal
             be
             found
             ,
             and
             Down
             ,
             as
             they
             term
             it
             ;
             that
             is
             ,
             the
             Dipp
             which
             it
             had
             naturally
             ,
             augmented
             .
             And
             ,
             if
             the
             Vise
             be
             Up
             ,
             the
             same
             way
             must
             be
             taken
             for
             piercing
             the
             Gae
             ,
             and
             the
             Coal
             will
             be
             found
             Up
             ,
             that
             is
             ,
             its
             Rise
             augmented
             .
             But
             these
             things
             cannot
             be
             made
             so
             intelligible
             ,
             as
             by
             seeing
             ,
             there
             being
             many
             things
             in
             the
             alteration
             of
             the
             course
             of
             Metals
             very
             curious
             ,
             and
             worthy
             of
             Observation
             :
             as
             when
             a
             Coal
             is
             cast
             down
             out
             of
             its
             natural
             course
             by
             a
             Gae
             ,
             and
             so
             made
             sometimes
             under-Level
             ,
             it
             riseth
             as
             much
             to
             another
             hand
             ,
             and
             the
             Cropps
             go
             so
             much
             farder
             out
             ,
             which
             still
             makes
             the
             Level
             useful
             ,
             the
             use
             whereof
             would
             have
             been
             judged
             lost
             by
             the
             down-casting
             .
             Sometimes
             a
             Coal
             made
             to
             have
             four
             contrary
             courses
             ,
             as
             is
             evident
             from
             the
             eighth
             Figure
             ,
             where
             there
             being
             a
             Gae
             at
             E
             ,
             makes
             it
             take
             such
             another
             course
             ,
             in
             stead
             of
             coming
             out
             to
             the
             grass
             .
             Sometimes
             ,
             before
             the
             Metals
             overtake
             the
             Gae
             ,
             they
             are
             made
             to
             ly
             like
             a
             Bowe
             ;
             one
             instance
             whereof
             is
             visible
             above
             ground
             in
             some
             Metals
             lying
             between
             Bruntiland
             and
             Kinghorn
             ,
             at
             a
             place
             called
             the
             Miln-stone
             ,
             where
             there
             is
             a
             small
             Coal
             with
             Free-stone
             above
             it
             ,
             all
             Dipping
             to
             the
             S
             E
             ,
             and
             Rising
             to
             the
             N
             W.
             Upon
             the
             Rise
             they
             meet
             with
             a
             gae
             ,
             which
             is
             a
             great
             Whin-rock
             .
             In
             their
             course
             to
             the
             grass
             ,
             before
             they
             touch
             the
             said
             Rock
             ,
             they
             take
             a
             contrary
             course
             ,
             and
             dipps
             into
             it
             ,
             and
             are
             there
             quite
             cut
             off
             .
             The
             manner
             whereof
             is
             to
             be
             seen
             in
             this
             tenth
             Figure
             following
             .
          
           
             
               Figure
               10.
               
            
          
           
             Where
             A
             B
             is
             the
             Rock
             :
             E
             F
             the
             Coal
             :
             C
             D
             the
             Free-stone
             .
             Now
             ,
             whereas
             they
             should
             have
             risen
             towards
             A
             ,
             they
             turn
             at
             D
             ,
             and
             dipps
             into
             the
             Rock
             ,
             which
             any
             may
             observe
             in
             passing
             that
             way
             .
             Many
             other
             such
             motions
             are
             observable
             ,
             which
             I
             pass
             ,
             and
             leaves
             them
             to
             the
             observation
             of
             the
             curious
             .
          
           
             The
             third
             thing
             I
             promised
             to
             speak
             of
             ,
             was
             of
             Damps
             ,
             and
             as
             they
             are
             termed
             by
             the
             
               Coal-hewers
               ,
               Ill
               Air.
            
             These
             do
             deserve
             a
             more
             accurat
             inquiry
             into
             their
             kinds
             ,
             their
             causes
             ,
             and
             effects
             ;
             then
             I
             am
             capable
             to
             make
             ,
             there
             being
             many
             things
             in
             them
             very
             considerable
             ,
             and
             worthy
             of
             a
             narrow
             search
             :
             therefore
             following
             the
             course
             I
             have
             hitherto
             observed
             ,
             I
             shall
             shew
             my
             own
             Observations
             thereof
             ,
             and
             leave
             the
             more
             curious
             search
             to
             the
             spirits
             fitted
             for
             that
             purpose
             .
          
           
             This
             Damp
             then
             makes
             an
             obstruction
             of
             respiration
             in
             Men
             ,
             or
             other
             living
             Creatures
             ,
             in
             Subterraneous
             spaces
             ,
             as
             
               Caves
               ,
               Coal-rooms
               ,
               Levels
               ,
               Sinks
               ,
            
             and
             such
             like
             ;
             which
             obstruction
             proceeds
             principally
             from
             two
             causes
             ,
             both
             which
             goes
             under
             the
             name
             of
             
               Ill
               Air
            
             ,
             among
             the
             vulgar
             .
             The
             first
             is
             the
             corruption
             ,
             or
             putrefaction
             of
             the
             Air
             ,
             whereof
             there
             are
             two
             sorts
             ;
             one
             is
             in
             places
             where
             
             hath
             been
             fire
             kindled
             ,
             which
             burns
             the
             Coal
             under
             ground
             ,
             the
             smoke
             whereof
             ,
             being
             full
             of
             Sulphur
             ,
             and
             other
             Bituminous
             matter
             ,
             and
             not
             having
             free
             passage
             to
             come
             above
             ground
             ,
             filleth
             all
             the
             
               waste
               Rooms
            
             under
             ground
             ,
             and
             infects
             the
             Air
             so
             ,
             that
             the
             smell
             of
             it
             ,
             even
             at
             a
             distance
             ,
             is
             intolerable
             ,
             and
             amongst
             it
             no
             living
             Creature
             is
             able
             to
             breath
             .
             Of
             this
             there
             are
             examples
             in
             Dysert
             in
             Fife
             ,
             and
             Fauside
             in
             East●Lothian
             .
             This
             was
             kindled
             on
             design
             by
             a
             Fellow
             ,
             who
             for
             his
             pains
             was
             hanged
             in
             the
             place
             ,
             and
             hath
             burnt
             these
             50
             years
             ,
             and
             more
             ,
             the
             fire
             whereof
             is
             sometimes
             seen
             near
             the
             grass
             ,
             with
             abundance
             of
             smoke
             ,
             as
             it
             runs
             from
             one
             place
             to
             another
             .
             The
             second
             ,
             where
             the
             Air
             is
             corrupted
             without
             the
             mixture
             of
             smoke
             ,
             or
             any
             other
             gross
             corrupting
             body
             ,
             which
             is
             the
             most
             considerable
             of
             all
             Damps
             ,
             and
             hath
             the
             strangest
             effects
             ,
             in
             killing
             Animals
             in
             an
             instant
             ,
             and
             so
             hath
             been
             alwayes
             most
             prejudicial
             in
             the
             works
             ,
             where
             it
             is
             found
             ,
             many
             persons
             having
             thereby
             lost
             their
             lives
             ,
             without
             access
             to
             cry
             but
             once
             
               Gods
               mercy
            
             ,
             to
             some
             instances
             whereof
             I
             have
             been
             witness
             .
             I
             shall
             not
             offer
             to
             determine
             about
             the
             cause
             of
             this
             Damp
             ,
             but
             shall
             give
             an
             account
             of
             somethings
             I
             have
             observed
             about
             it
             ,
             which
             when
             duely
             pondered
             ,
             may
             haply
             lay
             a
             foundation
             ,
             at
             least
             of
             a
             probable
             conjecture
             ,
             whence
             it
             may
             proceed
             .
          
           
             This
             kind
             of
             Damp
             then
             ,
             and
             
               Ill
               Air
            
             ,
             is
             never
             found
             in
             Coal
             ,
             or
             other
             Metals
             ,
             where
             there
             is
             Water
             to
             be
             found
             ;
             I
             mean
             ,
             whence
             the
             Water
             hath
             not
             been
             drawn
             away
             by
             a
             Level
             ,
             or
             Aquae-duct
             :
             as
             in
             Coals
             ,
             where
             there
             is
             a
             necessity
             to
             lave
             the
             Water
             from
             place
             to
             place
             ,
             or
             to
             pump
             it
             along
             the
             ascent
             or
             rise
             of
             the
             Coal
             ,
             to
             the
             bottom
             of
             the
             Sink
             ,
             from
             which
             it
             is
             drawn
             out
             above
             ground
             ,
             this
             
               Ill
               ●ir
            
             is
             not
             ●ound
             .
             Nor
             is
             found
             frequently
             ,
             if
             at
             all
             ,
             in
             
             these
             Coals
             where
             the
             Water
             is
             drawn
             from
             the
             Coal
             by
             a
             Level
             ,
             or
             Aquae-duct
             under
             ground
             ,
             till
             it
             come
             of
             its
             own
             accord
             to
             the
             bottom
             of
             a
             Sink
             ,
             which
             is
             in
             place
             of
             a
             Cistern
             ,
             out
             of
             which
             it
             is
             forced
             also
             above
             ground
             ,
             and
             differs
             only
             from
             the
             other
             ,
             that
             the
             Water
             runs
             here
             of
             its
             own
             accord
             by
             a
             descent
             to
             the
             Sink
             ,
             which
             is
             termed
             a
             
               drawing
               Sink
            
             :
             in
             the
             other
             it
             must
             be
             forced
             by
             the
             Rise
             of
             the
             Coal
             ,
             because
             happly
             ,
             a
             Sink
             upon
             the
             Dipp
             would
             be
             of
             such
             a
             deepness
             ,
             that
             no
             force
             could
             draw
             it
             up
             in
             a
             perpendicular
             .
          
           
             But
             this
             kind
             of
             Damp
             is
             found
             ordinarily
             in
             these
             Coals
             from
             which
             the
             Water
             is
             drawn
             by
             a
             Level
             ,
             the
             beginning
             or
             mouth
             whereof
             is
             above
             ground
             ,
             and
             carried
             along
             by
             a
             right
             Line
             under
             ground
             ,
             till
             it
             overtake
             the
             Coal
             ,
             which
             it
             is
             to
             dry
             :
             so
             that
             the
             Water
             which
             comes
             from
             the
             Coal
             ,
             runs
             without
             being
             forced
             ,
             and
             is
             sometimes
             so
             considerable
             ,
             that
             it
             makes
             Mills
             go
             ,
             without
             any
             other
             addition
             ,
             as
             is
             to
             be
             seen
             in
             the
             Earl
             of
             Wintons
             Lands
             of
             Seton
             ,
             where
             four
             Mills
             goes
             with
             the
             Water
             that
             comes
             from
             under
             ground
             ,
             out
             of
             the
             Coal
             ;
             which
             kind
             of
             Levels
             are
             only
             found
             where
             the
             Coal
             lyes
             in
             a
             Field
             ,
             which
             hath
             a
             considerable
             Rise
             ,
             or
             ascent
             above
             ground
             ;
             there
             being
             a
             necessity
             to
             make
             use
             of
             the
             other
             two
             wayes
             spoken
             of
             ,
             for
             drying
             the
             Coal
             ,
             when
             the
             Field
             in
             which
             it
             lyes
             is
             a
             Plain
             .
          
           
             Further
             ,
             of
             these
             Coals
             ,
             which
             are
             dryed
             by
             the
             Free-level
             (
             for
             so
             they
             term
             the
             Level
             that
             runs
             unforced
             )
             there
             are
             some
             to
             which
             this
             kind
             of
             Damp
             is
             more
             incident
             ,
             than
             to
             others
             .
             The
             cause
             of
             which
             difference
             is
             found
             to
             be
             ,
             the
             solidity
             and
             clossness
             of
             the
             Metals
             ,
             whether
             of
             Coal
             or
             Stone
             ,
             wherein
             some
             exceeds
             another
             .
             There
             being
             some
             ,
             that
             are
             full
             of
             rifts
             ,
             or
             empty
             spaces
             (
             I
             mean
             
             empty
             of
             any
             part
             of
             the
             same
             body
             where
             they
             are
             )
             which
             will
             sometimes
             serve
             ,
             to
             convey
             a
             considerable
             quantity
             of
             Water
             in
             place
             of
             an
             aquae-duct
             or
             level
             ;
             which
             spaces
             are
             termed
             by
             the
             vulgar
             ,
             Cutters
             ,
             which
             sometime●
             proves
             very
             profitable
             in
             the
             ground
             where
             they
             are
             found
             ,
             both
             in
             regard
             of
             the
             use
             they
             serve
             for
             ,
             in
             stead
             of
             Level
             ,
             and
             for
             rendring
             the
             Metals
             wherein
             they
             are
             found
             ,
             more
             easie
             to
             work
             ,
             in
             making
             them
             yeeld
             easily
             to
             the
             force
             of
             the
             wedge
             and
             leaver
             .
             Other
             Metals
             there
             are
             ,
             wherein
             few
             of
             these
             Cutters
             are
             to
             be
             found
             ,
             and
             if
             water
             be
             to
             be
             conveyed
             through
             them
             ,
             there
             is
             a
             necessity
             of
             cutting
             a
             passage
             through
             them
             for
             that
             effect
             .
             Now
             ,
             this
             Damp
             ,
             whereof
             we
             speak
             is
             found
             most
             frequently
             ,
             and
             most
             violent
             in
             the
             first
             sort
             of
             
               Metals
               ,
               viz.
            
             in
             these
             which
             are
             full
             of
             Cutters
             or
             Rifts
             ,
             which
             gives
             some
             ground
             to
             this
             conjecture
             of
             its
             cause
             .
             These
             Spaces
             which
             are
             found
             in
             Coal
             ,
             or
             other
             Metals
             ,
             as
             Stone
             or
             Till
             ,
             before
             the
             Coal
             begin
             to
             be
             dryed
             by
             a
             Level
             ,
             are
             full
             of
             water
             ,
             which
             is
             still
             in
             motion
             ,
             as
             are
             all
             
               subterraneous
               springs
            
             ,
             whereof
             some
             are
             more
             violent
             ,
             some
             more
             slow
             ,
             conform
             to
             the
             passage
             they
             have
             to
             the
             fountains
             above
             ground
             ,
             where
             they
             discharge
             themselves
             .
             Now
             ,
             for
             drying
             these
             Coals
             ,
             and
             rendring
             them
             workable
             ,
             there
             is
             a
             necessity
             to
             cut
             a
             passage
             ,
             thorow
             which
             that
             water
             discharges
             it self
             quickly
             ,
             it
             being
             large
             ,
             and
             admitting
             a
             great
             quantity
             at
             once
             ,
             by
             vertue
             whereof
             ;
             a
             great
             field
             is
             drained
             at
             once
             ,
             and
             the
             Sourse
             not
             being
             able
             to
             furnish
             so
             much
             water
             ,
             as
             the
             Conduit
             is
             able
             to
             convey
             ,
             these
             Spaces
             in
             the
             body
             of
             the
             Metals
             ,
             being
             emptied
             of
             Water
             ,
             must
             needs
             be
             filled
             with
             Air
             ,
             which
             Air
             having
             little
             contact
             and
             commerce
             ,
             with
             the
             great
             body
             of
             Air
             above
             ground
             ,
             and
             so
             hath
             little
             or
             ●o
             motion
             ,
             corrupts
             in
             these
             places
             ,
             and
             thereby
             becomes
             
             poisonable
             ,
             so
             that
             when
             any
             Animal
             is
             necessitat
             to
             draw
             it
             ,
             and
             respire
             by
             it
             ,
             it
             choaks
             them
             on
             a
             sudden
             ,
             just
             as
             standing
             Water
             ,
             which
             being
             without
             motion
             corrupts
             ,
             and
             becomes
             poisonable
             ,
             though
             haply
             not
             in
             so
             great
             a
             degree
             as
             the
             Air
             :
             the
             Air
             ,
             being
             a
             body
             much
             ●iner
             and
             purer
             ,
             than
             Water
             ,
             that
             holding
             good
             in
             it
             ,
             
               corruptio
               optimi
               pessima
            
             .
             This
             is
             much
             confirmed
             by
             what
             is
             before
             asserted
             ,
             that
             in
             the
             Coals
             ,
             whence
             the
             Water
             is
             drawn
             ,
             and
             they
             drained
             ,
             but
             not
             by
             free-course
             ,
             but
             by
             Force
             ,
             as
             Pumping
             ,
             and
             drawing
             by
             buckets
             ,
             these
             Damps
             are
             seldom
             or
             never
             found
             :
             because
             the
             passage
             of
             the
             Water
             being
             forced
             ,
             it
             does
             not
             so
             suddenly
             dry
             the
             Metals
             ,
             as
             the
             other
             ,
             whereby
             there
             is
             alwayes
             left
             in
             these
             Spaces
             some
             Water
             ,
             which
             being
             it self
             in
             motion
             ,
             keeps
             the
             Air
             also
             in
             motion
             with
             it
             ,
             and
             thereby
             the
             Air
             is
             kept
             from
             corruption
             ,
             at
             least
             in
             such
             a
             degree
             ,
             as
             it
             is
             in
             the
             other
             .
             Hence
             we
             find
             ,
             that
             in
             these
             kinds
             of
             Coals
             ,
             the
             Rooms
             under-ground
             are
             alwayes
             wet
             ,
             or
             for
             the
             most
             part
             they
             are
             so
             :
             whereas
             in
             the
             other
             ,
             there
             will
             be
             no
             Water
             found
             to
             wash
             a
             mans
             hands
             :
             and
             sometimes
             the
             Coal
             through
             want
             of
             Water
             ,
             becomes
             so
             dry
             ,
             that
             it
             cannot
             be
             wrought
             in
             great
             pieces
             ,
             as
             others
             ,
             but
             crushes
             in
             the
             very
             working
             ,
             and
             when
             wrought
             ,
             is
             rendered
             useless
             ,
             and
             will
             not
             at
             all
             burn
             .
             This
             puts
             me
             in
             mind
             of
             a
             very
             pleasant
             conception
             of
             a
             worthy
             and
             learned
             Person
             ,
             Doctor
             
               George
               Hepburn
            
             of
             Monk-ridge
             ,
             with
             whom
             I
             had
             occasion
             one
             day
             to
             discourse
             on
             this
             Subject
             .
             He
             is
             of
             opinion
             that
             the
             Water
             is
             the
             Mother
             of
             the
             Coal
             ,
             whereby
             it
             is
             preserved
             fresh
             ,
             and
             incorrupted
             ,
             and
             that
             when
             the
             Water
             is
             drawn
             off
             ,
             and
             this
             Damp
             follows
             ,
             it
             is
             not
             the
             Air
             ,
             which
             succeeds
             in
             place
             of
             the
             Water
             ,
             and
             is
             corrupted
             for
             want
             of
             motion
             ,
             that
             occasions
             it
             .
             But
             as
             we
             see
             ,
             when
             the
             corruption
             of
             a
             Liquor
             
             within
             a
             Vessel
             ,
             when
             the
             Mother
             is
             gone
             ,
             corrupts
             the
             Vessel
             it self
             ,
             and
             occasions
             an
             ill
             savour
             or
             taste
             in
             the
             Vessel
             ;
             so
             that
             the
             Coal
             being
             corrupted
             by
             the
             want
             of
             its
             Mother
             ,
             the
             Water
             ;
             corrupts
             the
             Air
             in
             the
             subterraneous
             Spaces
             ,
             as
             in
             
               Coal-Mines
               ,
               Sinks
               ,
               Caves
            
             ,
             and
             other
             such
             like
             .
             He
             had
             likewise
             another
             pleasant
             conception
             about
             the
             
               generation
               of
               Coal
            
             ,
             judging
             it
             to
             be
             formed
             gradually
             out
             of
             another
             Metal
             ,
             as
             of
             Till
             ,
             by
             the
             help
             of
             Water
             ,
             of
             which
             he
             himself
             may
             perhaps
             give
             an
             account
             ▪
             And
             though
             I
             be
             not
             of
             his
             opinion
             in
             that
             matter
             ,
             yet
             I
             must
             acknowledge
             ,
             I
             was
             taken
             with
             it
             ,
             and
             shall
             be
             glad
             to
             see
             a
             more
             full
             account
             of
             it
             from
             him
             ,
             than
             he
             had
             access
             to
             do
             in
             the
             short
             conference
             we
             had
             .
          
           
             The
             effects
             of
             this
             Damp
             are
             first
             ,
             it
             hinders
             the
             burning
             of
             all
             combustible
             matter
             ,
             as
             
               Candle
               ,
               Coal
               ,
               Pitch
               ,
               Sulphur
               ,
            
             &c.
             so
             that
             if
             you
             take
             a
             Torch
             lighted
             ,
             and
             let
             it
             down
             to
             a
             Sink
             ,
             where
             the
             
               Ill
               Air
            
             is
             prevalent
             in
             the
             time
             ,
             it
             shall
             straightway
             extinguish
             it
             .
             Or
             take
             a
             Coal
             ,
             which
             is
             burning
             ,
             and
             let
             it
             down
             ,
             it
             shall
             not
             only
             extinguish
             the
             Flame
             ,
             but
             shall
             make
             the
             Coal
             in
             an
             instant
             dead
             ,
             and
             as
             cold
             as
             never
             heat
             had
             been
             in
             it
             .
             But
             the
             most
             dangerous
             effect
             is
             ,
             its
             killing
             of
             
               living
               Creatures
            
             ,
             whereby
             many
             persons
             have
             been
             suddenly
             killed
             .
             Some
             in
             going
             down
             to
             a
             Sink
             ,
             where
             it
             hath
             been
             powerful
             ,
             have
             fallen
             out
             of
             the
             Rope
             ,
             and
             perished
             .
             Others
             have
             been
             choaked
             ,
             and
             yet
             have
             gotten
             out
             by
             the
             help
             of
             others
             in
             a
             sudden
             ,
             and
             have
             remained
             a
             considerable
             time
             without
             the
             least
             appearance
             of
             life
             ,
             but
             yet
             have
             at
             last
             recovered
             .
             Yet
             it
             hath
             been
             observed
             ,
             that
             some
             of
             these
             persons
             that
             have
             been
             so
             struck
             with
             the
             Damp
             ,
             and
             recovered
             ,
             have
             had
             alwayes
             some
             
               lightness
               of
               Brain
            
             thereafter
             ,
             and
             never
             so
             settled
             as
             formerly
             .
             This
             I
             know
             to
             have
             happened
             to
             one
             ,
             whom
             I
             have
             seen
             so
             ,
             many
             times
             thereafter
             .
          
           
           
             What
             hath
             been
             its
             effects
             on
             some
             Animals
             ,
             whereof
             you
             have
             made
             Experiment
             ,
             I
             leave
             to
             the
             account
             you
             have
             given
             .
             One
             thing
             I
             shall
             only
             mention
             ,
             which
             to
             me
             seems
             somewhat
             strange
             ,
             that
             notwithstanding
             these
             Damps
             are
             so
             effectual
             ,
             and
             causeth
             so
             suddenly
             the
             death
             of
             Animals
             ,
             yet
             the
             Ratts
             ,
             which
             are
             in
             some
             of
             these
             places
             ,
             where
             the
             Damps
             are
             most
             violent
             ,
             are
             not
             reached
             by
             them
             .
             For
             sometimes
             ,
             when
             they
             are
             so
             powerful
             ,
             that
             nothing
             that
             lives
             can
             enter
             under
             ground
             ,
             without
             sudden
             death
             ,
             yet
             they
             continue
             there
             ,
             and
             are
             not
             found
             to
             diminish
             ,
             even
             where
             they
             have
             no
             access
             to
             escape
             ,
             by
             coming
             above
             ground
             .
             Or
             if
             it
             should
             be
             imagined
             ,
             they
             removed
             to
             some
             other
             place
             of
             the
             ground
             ,
             where
             the
             Damp
             is
             not
             ,
             how
             is
             it
             ,
             they
             are
             not
             as
             quickly
             choaked
             with
             it
             ,
             as
             Dogs
             are
             ,
             and
             other
             Animals
             ,
             which
             at
             the
             first
             encounter
             are
             killed
             ?
          
           
             If
             it
             be
             inquired
             ,
             how
             comes
             it
             to
             pass
             ,
             that
             in
             these
             Fields
             of
             Coals
             ,
             which
             are
             dryed
             fully
             (
             as
             was
             said
             )
             and
             to
             which
             these
             Damps
             are
             incident
             ,
             because
             of
             corrupted
             Air
             that
             remains
             within
             the
             Body
             of
             the
             Coal
             ,
             or
             other
             Metals
             ,
             how
             comes
             it
             to
             pass
             (
             I
             say
             )
             that
             they
             are
             but
             sometimes
             incident
             ,
             and
             are
             not
             alwayes
             found
             ?
             For
             clearing
             this
             ,
             it
             is
             certain
             ,
             that
             even
             in
             the
             grounds
             ,
             where
             these
             Damps
             are
             most
             frequent
             ,
             for
             the
             reasons
             above-mentioned
             ,
             yet
             they
             are
             only
             powerful
             when
             the
             Wind
             blows
             from
             such
             a
             certain
             Point
             ,
             as
             some
             Chimneys
             ,
             that
             do
             only
             smoke
             ,
             when
             the
             Wind
             is
             in
             such
             an
             Airth
             .
             This
             is
             so
             generally
             ,
             and
             well
             known
             ,
             that
             the
             Work-men
             observe
             it
             ,
             and
             when
             they
             find
             the
             Wind
             in
             such
             a
             Point
             ,
             whence
             they
             fear
             the
             Damp
             ,
             they
             will
             not
             enter
             under
             ground
             ,
             till
             trial
             be
             made
             of
             the
             Air
             ,
             which
             they
             do
             in
             Sinks
             ,
             by
             first
             letting
             
             down
             a
             lighted
             Candle
             ,
             or
             some
             burning
             Coals
             :
             which
             if
             they
             do
             not
             burn
             ,
             then
             there
             is
             no
             access
             to
             enter
             .
          
           
             Secondly
             ,
             the
             wind
             in
             which
             this
             
               Ill
               Air
            
             is
             most
             noxious
             ,
             and
             hurtful
             ,
             blows
             from
             that
             Point
             ,
             where
             the
             Field
             of
             Coal
             lyes
             ,
             that
             's
             not
             yet
             wrought
             ,
             which
             seems
             somewhat
             strange
             ,
             and
             yet
             when
             duely
             considered
             ,
             it
             will
             appear
             abundantly
             consonant
             to
             reason
             .
             An
             example
             of
             this
             is
             to
             be
             found
             in
             the
             Coal
             of
             Tranent
             and
             Elphingston
             ,
             the
             Streek
             whereof
             goes
             to
             the
             rise
             of
             the
             Hill
             above
             ground
             ,
             from
             N
             E
             to
             S
             W
             ,
             as
             hath
             been
             formerly
             observed
             .
             So
             that
             the
             beginning
             of
             their
             Level
             ,
             is
             at
             the
             N
             E
             point
             of
             the
             Streek
             ,
             from
             which
             the
             Coal
             hath
             been
             wrought
             up
             along
             the
             Streek
             towards
             the
             S
             W
             ,
             the
             Wastes
             lying
             all
             towards
             the
             N
             E.
             Yet
             when
             the
             Wind
             blows
             from
             N
             E
             ,
             or
             N
             ,
             or
             almost
             from
             any
             other
             Point
             of
             the
             Compass
             ,
             they
             are
             not
             troubled
             with
             this
             Damp.
             But
             if
             it
             blow
             from
             S
             W
             ,
             and
             blow
             hard
             ,
             they
             are
             in
             hazard
             to
             encounter
             it
             .
             And
             though
             the
             Damp
             is
             not
             alwayes
             found
             when
             that
             Wind
             blows
             (
             whereof
             there
             may
             be
             some
             particular
             cause
             )
             yet
             it
             is
             never
             observed
             in
             another
             Wind
             ,
             whether
             it
             blow
             less
             or
             mo●e
             :
             the
             reason
             whereof
             may
             probably
             be
             ,
             that
             the
             Wind
             blowing
             from
             other
             Points
             ,
             as
             from
             N
             ,
             or
             N
             E
             ,
             hath
             more
             access
             to
             enter
             the
             Wastes
             under
             ground
             ,
             and
             move
             the
             Air
             that
             is
             in
             them
             ,
             towards
             the
             face
             of
             the
             unwrought
             Coal
             ,
             whence
             is
             supposed
             to
             proceed
             the
             corrupted
             Air
             ,
             that
             lurks
             in
             the
             Rifts
             and
             Cutters
             thereof
             ,
             (
             from
             which
             the
             Water
             is
             drawn
             away
             ,
             )
             and
             occasions
             the
             
               Damp
               ▪
            
             Now
             this
             Air
             being
             moved
             by
             the
             force
             of
             the
             Wind
             ,
             keeps
             the
             corrupt
             Air
             from
             coming
             out
             ,
             it
             being
             stronger
             then
             the
             other
             .
             Whereas
             ,
             upon
             the
             contrary
             ,
             while
             the
             Wind
             blows
             from
             S
             W
             ,
             it
             entering
             the
             empty
             Rooms
             ,
             drives
             the
             Air
             under
             ground
             from
             the
             face
             of
             the
             unwrought
             
             Coal
             ,
             down
             towards
             the
             
               old
               wastes
            
             ,
             which
             have
             their
             course
             from
             the
             beginning
             of
             the
             Level
             .
             By
             which
             means
             ,
             the
             Air
             ,
             that
             is
             corrupted
             within
             the
             bowels
             (
             to
             speak
             so
             )
             of
             the
             Coal
             ,
             comes
             out
             to
             the
             Wastes
             ,
             without
             resistance
             ,
             it
             being
             certain
             ,
             that
             
               Fluid
               Bodies
            
             ,
             as
             Water
             ,
             and
             Air
             ,
             inclines
             to
             move
             towards
             that
             place
             ,
             where
             they
             meet
             with
             the
             least
             resistance
             .
             Hence
             is
             it
             ,
             that
             the
             more
             direct
             the
             Wind
             be
             ,
             in
             blowing
             against
             the
             ●ace
             of
             the
             unwrought
             Coal
             ,
             as
             is
             the
             Wind
             from
             N
             E
             ,
             the
             
               Ill
               Air
            
             is
             the
             more
             repelled
             and
             driven
             back
             ,
             but
             the
             more
             oblique
             it
             be
             ,
             as
             are
             the
             Winds
             from
             these
             Points
             ,
             that
             are
             nearest
             to
             S
             W
             ,
             the
             Air
             is
             not
             so
             good
             and
             free
             :
             which
             difference
             is
             known
             by
             the
             burning
             of
             Candles
             ,
             they
             burning
             with
             greater
             difficulty
             in
             these
             Winds
             ,
             than
             in
             others
             ,
             which
             blow
             from
             these
             Points
             nearest
             to
             N
             ,
             and
             N
             E.
             Some
             are
             of
             opinion
             ,
             this
             
               Ill
               Air
            
             (
             in
             those
             places
             we
             have
             been
             speaking
             of
             )
             comes
             from
             the
             great
             Wastes
             ,
             that
             ly
             above
             the
             un-wrought
             Coal
             ,
             and
             by
             strong
             S
             W
             Winds
             is
             driven
             thorow
             the
             Cutters
             thereof
             .
             Or
             the
             Wind
             blowing
             from
             that
             Point
             ,
             and
             coming
             thorow
             these
             Cutters
             ,
             brings
             the
             corrupted
             Air
             alongs
             with
             it
             ,
             even
             as
             ,
             after
             a
             showr
             of
             Rain
             ,
             a
             spait
             of
             Water
             comes
             ,
             and
             carries
             alongs
             with
             it
             ,
             both
             the
             foul
             Water
             and
             the
             clean
             ,
             it
             meets
             with
             .
             Though
             this
             may
             be
             probable
             ,
             which
             seems
             to
             be
             your
             own
             opinion
             ,
             yet
             the
             other
             seems
             to
             be
             more
             probable
             .
          
           
             The
             other
             sort
             of
             Damp
             ,
             is
             that
             which
             they
             call
             
               want
               of
               Air
            
             ;
             and
             though
             the
             term
             be
             not
             altogether
             proper
             (
             there
             being
             no
             space
             without
             some
             Air
             )
             yet
             there
             is
             a
             want
             of
             Air
             ,
             which
             is
             sufficient
             for
             respiration
             of
             Animals
             ,
             or
             for
             the
             burning
             of
             fire
             .
             This
             is
             ordinarily
             ●ound
             in
             the
             vunning
             of
             Mines
             under
             ground
             ,
             for
             co●veying
             of
             Water
             from
             Coal
             ,
             or
             other
             Metals
             ,
             or
             in
             the
             
               waste
               Roo●s
            
             of
             Coals
             ,
             where
             
             the
             Sinks
             are
             very
             deep
             ,
             and
             to
             evite
             the
             charge
             thereof
             ,
             there
             is
             some
             necessity
             to
             work
             as
             far
             under
             ground
             for
             winning
             of
             Coal
             ,
             as
             is
             possible
             ,
             without
             new
             Sinks
             .
             The
             cause
             seems
             to
             be
             ,
             that
             the
             Air
             under
             ground
             ,
             in
             such
             cases
             ,
             wants
             communication
             with
             the
             Air
             above
             ground
             ,
             because
             it
             is
             found
             ,
             that
             by
             giving
             more
             communication
             ,
             the
             evil
             is
             cured
             .
             Whence
             comes
             the
             necessity
             of
             Air-holes
             in
             Levels
             ,
             which
             are
             so
             many
             Sinks
             set
             down
             ,
             for
             no
             other
             use
             ,
             but
             for
             giving
             Air
             to
             the
             Workers
             .
             Some
             are
             of
             opinion
             ,
             that
             this
             defect
             might
             be
             supplied
             by
             the
             blowing
             of
             Bellows
             ,
             from
             above
             ground
             ,
             through
             a
             Stroop
             of
             Leather
             ,
             or
             of
             some
             other
             thing
             ,
             which
             must
             run
             along
             to
             the
             end
             of
             the
             Level
             ,
             for
             keeping
             the
             Air
             there●in
             motion
             .
             But
             I
             have
             not
             yet
             heard
             ,
             that
             it
             hath
             been
             made
             practicable
             .
          
           
             The
             effects
             of
             this
             Damp
             are
             not
             so
             dangerous
             ,
             as
             these
             of
             the
             other
             .
             'T
             is
             true
             ,
             it
             will
             kill
             Animals
             ,
             and
             extinguish
             burning
             Coals
             and
             Candles
             ,
             but
             not
             so
             suddenly
             as
             the
             former
             ;
             and
             so
             people
             are
             not
             so
             readily
             surprized
             by
             it
             .
             The
             other
             seems
             to
             kill
             by
             some
             poisonous
             quality
             :
             in
             this
             Animals
             dies
             for
             want
             of
             sufficient
             Air
             for
             respiration
             .
             Therefore
             in
             advancing
             in
             a
             
               Coal
               Room
            
             ,
             or
             Level
             where
             this
             is
             ,
             you
             shall
             see
             the
             flame
             of
             the
             Candle
             grow
             less
             and
             less
             by
             degrees
             ,
             till
             at
             last
             it
             be
             totally
             extinguished
             ,
             and
             the
             person
             entering
             ,
             shall
             find
             the
             difficulty
             of
             breathing
             grow
             greater
             ,
             as
             he
             advanceth
             forward
             ,
             till
             at
             last
             he
             cannot
             breath
             at
             all
             .
             Hence
             it
             is
             ,
             that
             few
             or
             none
             are
             killed
             by
             this
             kind
             of
             Damp
             ,
             and
             all
             its
             prejudice
             is
             ,
             that
             it
             renders
             the
             work
             more
             chargeable
             ,
             when
             there
             is
             a
             necessity
             to
             remove
             it
             .
          
           
             For
             that
             ,
             which
             they
             call
             Wild-fire
             ,
             it
             being
             a
             thing
             not
             incident
             ,
             but
             to
             very
             few
             Coals
             ,
             is
             less
             known
             ,
             than
             any
             of
             the
             rest
             of
             the
             accidents
             that
             follows
             Coals
             .
             The
             account
             
             I
             have
             heard
             of
             it
             ,
             is
             ,
             that
             in
             some
             Coals
             ,
             which
             naturally
             are
             full
             of
             Oil
             ,
             and
             that
             are
             (
             as
             they
             call
             them
             )
             
               fatt
               Coals
            
             ,
             there
             is
             a
             certain
             Fire
             ,
             which
             is
             as
             a
             Meteor
             ,
             and
             I
             judge
             ,
             that
             from
             its
             resemblance
             to
             
               Ignis
               fat●●s
            
             ,
             which
             the
             Vulgar
             termeth
             
               Wild
               fire
            
             ,
             it
             hath
             the
             sa●e
             name
             .
             It
             seems
             to
             be
             composed
             of
             some
             
               fatt
               oily
               vapour
            
             ,
             that
             goeth
             out
             of
             the
             Coal
             ,
             the
             Pores
             thereof
             being
             once
             opened
             ,
             which
             is
             kindled
             after
             the
             same
             manner
             ,
             as
             those
             fires
             above
             ground
             are
             ,
             which
             are
             most
             ordinarily
             found
             in
             fatt
             ,
             and
             marrish
             ground
             .
             Of
             this
             fire
             it
             is
             reported
             ,
             that
             in
             the
             day
             time
             ,
             while
             the
             
               Work
               men
            
             ,
             are
             working
             in
             the
             Coal-roomes
             ,
             it
             comes
             to
             no
             height
             ,
             though
             it
             be
             sometimes
             seen
             in
             little
             holes
             of
             the
             Coal-wall
             ,
             shining
             like
             kindled
             sulphure
             ,
             but
             without
             force
             :
             but
             when
             the
             Work-men
             are
             once
             removed
             ,
             and
             have
             stayed
             out
             all
             night
             ,
             it
             gathers
             to
             such
             a
             strength
             ,
             that
             at
             its
             first
             encountering
             with
             fire
             ,
             which
             the
             Coal-hewers
             are
             necessitate
             to
             have
             ,
             by
             taking
             in
             of
             light
             ,
             it
             breaks
             out
             with
             such
             a
             violence
             ,
             that
             it
             kills
             any
             person
             ,
             it
             finds
             in
             its
             way
             .
             The
             reason
             ,
             why
             it
             is
             without
             this
             force
             ,
             while
             the
             Workmen
             are
             in
             the
             place
             ,
             seems
             to
             be
             this
             ,
             that
             they
             working
             with
             such
             violence
             ,
             and
             motion
             as
             they
             do
             ,
             do
             certainly
             move
             the
             Air
             considerably
             ,
             it
             being
             contained
             in
             so
             narrow
             a
             place
             ,
             as
             a
             Coal-room
             .
             And
             this
             Air
             being
             violented
             by
             motion
             ,
             moves
             that
             
               oily
               vapour
            
             ,
             whereof
             the
             fire
             is
             formed
             ,
             so
             that
             it
             gets
             not
             liberty
             to
             unit
             it self
             ,
             being
             dissipated
             by
             the
             motion
             of
             the
             Air.
             But
             so
             soon
             ,
             as
             the
             Air
             is
             still
             ,
             and
             quiet
             ,
             after
             the
             Work-men
             are
             gone
             home
             ,
             it
             units
             it self
             ,
             and
             gathers
             force
             ,
             and
             therefore
             ,
             so
             soon
             ,
             as
             it
             meets
             with
             fire
             ,
             which
             is
             more
             forcible
             ,
             than
             the
             flame
             that
             is
             kindled
             in
             it
             ,
             it
             rarifieth
             ;
             the
             sulphurious
             parts
             being
             kindled
             ,
             and
             forceth
             it self
             out
             ,
             as
             powder
             out
             of
             a
             Gun.
             For
             it
             hath
             been
             observed
             ,
             that
             if
             any
             person
             stay
             in
             the
             Coal-sink
             
             while
             it
             breaks
             within
             the
             Coal-room
             ,
             they
             are
             in
             danger
             of
             being
             killed
             .
             The
             ordinary
             way
             by
             which
             the
             hurt
             of
             it
             is
             prevented
             ,
             is
             by
             a
             person
             that
             enters
             ,
             before
             the
             Work-men
             ,
             who
             being
             covered
             with
             wet●sack-cloath
             ,
             when
             he
             comes
             near
             the
             Coal-wall
             ,
             where
             the
             Fire
             is
             feared
             ,
             he
             creepeth
             on
             his
             belly
             ,
             with
             a
             long
             Poll
             before
             him
             ,
             with
             a
             lighted
             candle
             on
             the
             end
             thereof
             ,
             with
             whose
             flame
             the
             Wild-fire
             meeting
             ,
             breaketh
             with
             violence
             ,
             and
             running
             alongs
             the
             roof
             ,
             goeth
             out
             with
             a
             noise
             ,
             at
             the
             mouth
             of
             the
             Sink
             ,
             the
             person
             that
             gave
             fire
             ,
             having
             escaped
             ,
             by
             creeping
             on
             the
             ground
             ,
             and
             keeping
             his
             face
             close
             to
             it
             ,
             till
             it
             be
             over-passed
             ,
             which
             is
             in
             a
             moment
             .
          
           
             The
             place
             ,
             where
             this
             was
             most
             known
             ,
             was
             in
             a
             Coal
             be-west
             Leith
             ,
             in
             a
             piece
             of
             Land
             called
             Werdy
             ,
             which
             for
             want
             of
             Level
             ,
             and
             the
             violence
             of
             that
             Fire
             ,
             the
             Owners
             were
             forced
             to
             abandon
             .
          
           
             I
             come
             now
             to
             the
             last
             part
             ,
             which
             I
             promised
             to
             speak
             of
             ,
             namely
             of
             the
             best
             way
             for
             trying
             of
             grounds
             ,
             to
             find
             Coal
             ,
             where
             never
             any
             hath
             hitherto
             been
             discovered
             ,
             and
             of
             carrying
             on
             of
             Levels
             ,
             for
             draining
             the
             Water
             of
             Coals
             and
             making
             it
             workable
             .
             As
             to
             the
             first
             part
             ,
             there
             are
             but
             three
             wayes
             .
             First
             by
             sinking
             ,
             which
             is
             most
             chargeable
             ,
             in
             regard
             ,
             that
             in
             such
             grounds
             ,
             where
             the
             Metals
             are
             all
             intire
             ▪
             Water
             abounds
             ,
             and
             this
             doth
             not
             only
             bring
             the
             Master
             under
             a
             necessity
             of
             great
             expence
             for
             drawing
             the
             Water
             ,
             but
             also
             rendereth
             it
             impossible
             to
             get
             sinked
             to
             any
             deepness
             ,
             which
             may
             suffice
             ,
             for
             giving
             an
             account
             of
             all
             the
             Metals
             to
             be
             found
             ,
             within
             the
             field
             ,
             that
             may
             be
             rendred
             workable
             .
             There
             was
             a
             second
             way
             invented
             to
             supply
             this
             defect
             ,
             which
             is
             by
             boaring
             ,
             with
             an
             instrument
             made
             of
             several
             Rods
             of
             Iron
             ,
             which
             boareth
             thorow
             the
             Metals
             ,
             and
             tryes
             them
             .
             This
             way
             in
             my
             opinion
             ,
             is
             
             worse
             then
             the
             former
             .
             For
             first
             ,
             if
             the
             Coal
             ly
             deep
             ,
             in
             the
             place
             where
             you
             try
             by
             boaring
             ,
             it
             becomes
             almost
             as
             tedious
             ,
             and
             expensive
             ,
             as
             sinking
             ,
             the
             drawing
             of
             the
             ●odes
             ,
             consuming
             so
             much
             time
             ,
             in
             regard
             it
             must
             be
             frequently
             done
             .
             Next
             ,
             in
             boaring
             ,
             suppose
             the
             nature
             of
             the
             Metals
             ,
             be
             found
             ,
             yet
             thereby
             their
             course
             can
             never
             be
             known
             ,
             till
             they
             be
             sinked
             ,
             which
             is
             one
             of
             the
             things
             most
             considerable
             in
             the
             search
             of
             a
             Coal
             ,
             because
             thereby
             is
             known
             ,
             whether
             it
             be
             workable
             ,
             with
             advantage
             or
             not
             ,
             and
             whether
             it
             be
             possible
             to
             draw
             Water
             from
             it
             by
             a
             Level
             ,
             or
             otherwise
             .
             Lastly
             ,
             this
             way
             leaves
             the
             Master
             at
             an
             uncertainty
             (
             notwithstanding
             the
             Coal
             had
             been
             found
             )
             of
             its
             goodness
             ,
             as
             to
             its
             nature
             ,
             and
             as
             to
             its
             thickness
             .
             As
             to
             its
             goodness
             ,
             because
             all
             that
             is
             found
             of
             the
             Coal
             ,
             by
             this
             
               boaring
               instrument
            
             ,
             is
             some
             small
             dr●ss
             ,
             which
             remains
             after
             the
             washing
             of
             the
             thing
             that
             's
             brought
             up
             in
             the
             wumble
             ,
             by
             which
             none
             can
             judge
             of
             its
             goodness
             ,
             or
             badness
             .
             As
             to
             its
             thickness
             ,
             because
             it
             is
             impossible
             to
             discern
             exactly
             ,
             when
             the
             boaring-instrument
             hath
             passed
             the
             Coal
             :
             all
             the
             rule
             for
             trying
             thereof
             ,
             being
             the
             kind
             of
             Metal
             that
             is
             brought
             up
             in
             the
             wumble
             .
             Now
             ,
             I
             have
             known
             in
             my
             experience
             a
             
               Coal
               boared
            
             ,
             which
             the
             Boarer
             by
             that
             rule
             hath
             judged
             four
             foot
             in
             thickness
             ,
             yet
             when
             it
             came
             to
             be
             sinked
             ,
             hath
             not
             proven
             one
             .
             The
             reason
             whereof
             ,
             is
             obvious
             ,
             because
             the
             boaring-irons
             ,
             being
             long
             ,
             and
             weighty
             in
             lifting
             them
             up
             ,
             and
             down
             ,
             they
             break
             the
             Coal
             ,
             already
             pierced
             ;
             and
             this
             falling
             down
             among
             the
             Metals
             ,
             they
             are
             piercing
             ,
             and
             being
             found
             in
             the
             wumble
             with
             them
             (
             especially
             when
             the
             Metal
             under
             the
             Coal
             ,
             is
             a
             
               black
               Till
            
             )
             gives
             ground
             to
             imagine
             ,
             that
             all
             that
             time
             ,
             they
             have
             been
             peircing
             a
             Coal
             ,
             and
             so
             consequently
             ,
             the
             Coal
             must
             be
             of
             such
             a
             thickness
             .
          
           
           
             The
             last
             ,
             and
             best
             way
             of
             trial
             ,
             is
             that
             which
             is
             termed
             an
             
               ranging
               over
               the
               Metals
            
             .
             For
             doing
             whereof
             ,
             this
             method
             ,
             is
             to
             be
             observed
             .
             Suppose
             there
             be
             any
             place
             within
             the
             ground
             to
             be
             searched
             ,
             where
             the
             course
             of
             Metals
             can
             be
             seen
             ,
             as
             in
             the
             banks
             of
             a
             River
             ,
             or
             Rivolet
             ,
             or
             Sea-banks
             ,
             when
             the
             place
             is
             near
             the
             Sea
             ,
             then
             consideration
             must
             be
             had
             how
             far
             the
             lowest
             of
             these
             Metals
             ,
             can
             go
             before
             they
             Crop
             out
             to
             the
             Grass
             ,
             which
             will
             be
             known
             by
             observing
             the
             Dipp
             or
             declination
             of
             the
             Metals
             ,
             and
             the
             Rise
             of
             the
             ground
             above
             ,
             whereof
             a
             just
             allowance
             must
             be
             given
             ,
             and
             having
             digged
             before
             the
             said
             Crop
             ,
             you
             shall
             certainly
             find
             ,
             the
             Metal
             ,
             that
             is
             next
             under
             it
             ,
             and
             if
             that
             prove
             not
             Coal
             ,
             keeping
             the
             former
             proportion
             ,
             you
             must
             advance
             ,
             and
             digg
             before
             its
             Crop
             ,
             and
             so
             shall
             you
             find
             ,
             the
             next
             Metal
             under
             it
             ,
             and
             so
             still
             ,
             till
             you
             have
             tried
             your
             ground
             ,
             and
             found
             the
             Crops
             of
             all
             your
             Metals
             within
             it
             .
             But
             if
             there
             be
             no
             Water-banks
             ,
             or
             such
             like
             ,
             to
             give
             you
             the
             first
             view
             ,
             of
             the
             course
             of
             your
             Metals
             ,
             then
             must
             you
             sink
             first
             at
             random
             ,
             and
             having
             once
             past
             the
             Clay
             ,
             you
             will
             readily
             overtake
             some
             Metals
             ,
             whereby
             you
             will
             know
             the
             course
             of
             the
             rest
             ,
             and
             having
             once
             found
             the
             Dipp
             and
             Rise
             ,
             you
             must
             follow
             the
             method
             of
             ranging
             already
             prescribed
             ,
             except
             the
             ground
             so
             to
             be
             tried
             ,
             contains
             not
             within
             it self
             the
             Crops
             of
             the
             Metals
             ,
             the
             body
             whereof
             lies
             in
             it
             ,
             whether
             of
             Coal
             ,
             or
             Stone
             ,
             in
             that
             case
             ,
             there
             is
             no
             way
             to
             try
             ,
             but
             by
             sinking
             ,
             or
             boaring
             .
             The
             way
             of
             ranging
             is
             conspicuous
             in
             the
             following
             figure
             .
          
           
             
               Figure
               11.
               
            
          
           
             The
             piece
             of
             ground
             to
             be
             tried
             ,
             is
             P
             N
             ,
             where
             there
             are
             several
             Seams
             of
             Metals
             ,
             that
             Cropps
             out
             at
             the
             Points
             K
             L
             M
             N.
             Suppose
             the
             lowest
             to
             be
             the
             
               Coal
               ,
               viz.
            
             I
             N
             ,
             for
             which
             you
             are
             to
             make
             trial
             .
             You
             Digg
             first
             at
             K
             ,
             without
             the
             Cropp
             of
             the
             Seam
             F
             K
             ,
             and
             you
             dig
             till
             you
             find
             the
             other
             Seam
             of
             Stone
             G
             L
             ,
             at
             the
             Point
             C.
             Following
             the
             Rule
             before
             given
             ,
             you
             advance
             before
             its
             cropp
             ,
             and
             diggs
             at
             L
             ,
             and
             finds
             the
             other
             Seam
             of
             Stone
             H
             M
             ,
             at
             the
             point
             D
             :
             from
             which
             you
             also
             advance
             ,
             and
             diggs
             before
             its
             cropp
             ,
             at
             the
             point
             M
             ,
             and
             finds
             your
             Coal
             at
             the
             point
             E.
             But
             ,
             if
             by
             advancing
             over
             the
             cropps
             of
             these
             Metals
             ,
             which
             comes
             out
             from
             under
             one
             another
             ,
             you
             find
             no
             Coal
             ;
             then
             you
             are
             to
             range
             backward
             ,
             for
             the
             cropps
             of
             Metals
             lying
             above
             these
             ,
             where
             haply
             the
             Coal
             may
             be
             ,
             as
             at
             O
             ,
             and
             P.
             This
             in
             my
             opinion
             ,
             is
             the
             most
             certain
             and
             exact
             way
             of
             trying
             Fields
             for
             Coal
             ,
             or
             any
             other
             Metal
             of
             that
             nature
             ,
             and
             least
             chargeable
             of
             all
             others
             .
          
           
             The
             second
             of
             this
             last
             part
             ,
             I
             promised
             to
             speak
             of
             ,
             was
             in
             order
             to
             Levels
             ,
             or
             Coal-Mines
             ,
             which
             are
             nothing
             else
             ,
             but
             Conduits
             or
             Gutters
             made
             under
             ground
             ,
             for
             conveying
             of
             the
             Water
             from
             the
             Coal
             ,
             and
             so
             rendering
             it
             
             workable
             .
             It
             seems
             that
             a
             very
             little
             time
             before
             this
             ,
             that
             way
             of
             Mineing
             under
             ground
             hath
             not
             been
             fallen
             upon
             .
             For
             there
             are
             to
             be
             found
             Coals
             wasted
             in
             their
             Cropps
             only
             ;
             for
             conveying
             the
             Water
             whereof
             ,
             they
             have
             made
             a
             Conduit
             ,
             or
             Level
             ,
             which
             hath
             been
             
               open
               to
               the
               Surface
            
             ,
             like
             a
             great
             Ditch
             ,
             some
             whereof
             have
             been
             ten
             or
             twelve
             fathom
             in
             their
             deepness
             .
          
           
             The
             beginning
             of
             the
             Level
             (
             to
             keep
             the
             term
             used
             )
             must
             alwayes
             be
             at
             the
             lowest
             part
             of
             the
             Field
             ,
             where
             the
             Coal
             lyes
             to
             be
             dryed
             .
             Some
             whereof
             ,
             by
             the
             rising
             of
             the
             ground
             ,
             and
             the
             Streek
             of
             the
             Coal
             rising
             that
             way
             (
             as
             we
             shew
             before
             )
             gives
             the
             advantage
             of
             a
             
               Free
               Level
            
             ,
             that
             is
             ,
             when
             the
             Water
             comes
             above
             ground
             of
             its
             own
             accord
             ,
             without
             being
             forced
             by
             drawing
             .
             In
             others
             ,
             there
             is
             a
             necessity
             of
             Engines
             to
             draw
             the
             Water
             from
             the
             lowest
             part
             of
             the
             Level
             ,
             and
             bring
             it
             above
             ground
             ;
             which
             Engines
             are
             of
             several
             sorts
             .
             As
             when
             
               men
               drew
            
             with
             ordinary
             Buckets
             ,
             or
             when
             there
             is
             a
             horse-work
             ,
             or
             water-work
             ,
             and
             that
             either
             by
             a
             Chain
             with
             Plates
             ,
             and
             a
             Pump
             ,
             or
             with
             a
             Chain
             and
             Buckets
             ;
             all
             which
             are
             very
             common
             ,
             especially
             those
             we
             have
             in
             Scotland
             ,
             they
             being
             capable
             to
             draw
             but
             a
             very
             small
             draught
             ,
             making
             only
             use
             of
             one
             Sink
             for
             that
             effect
             .
             But
             there
             are
             to
             be
             seen
             in
             the
             North
             of
             England
             ,
             in
             
               Bishoprick
               ,
               Water-works
            
             ,
             by
             which
             Water
             is
             drawn
             above
             40
             fathom
             in
             perpendicular
             ,
             but
             not
             all
             in
             one
             Sink
             .
             The
             manner
             whereof
             is
             thus
             ,
             there
             being
             a
             Sink
             from
             the
             end
             of
             their
             Level
             ,
             to
             the
             surface
             of
             the
             earth
             ,
             where
             their
             Works
             are
             going
             ,
             40
             fathom
             deep
             ,
             which
             must
             dry
             the
             Coal-Sinks
             at
             60
             or
             70
             ,
             which
             ly
             above
             the
             Banks
             of
             the
             River
             ,
             where
             the
             Water-works
             are
             scituated
             ,
             there
             is
             first
             one
             40
             fathom
             deep
             from
             the
             Grass
             .
             Another
             in
             a
             right
             Line
             from
             that
             ,
             of
             24.
             
             Another
             of
             12
             ;
             upon
             all
             which
             
             there
             are
             Water-works
             .
             In
             the
             first
             Sink
             the
             Water
             is
             drawn
             from
             the
             bottom
             12
             fathom
             ,
             and
             thence
             conveyed
             into
             a
             Level
             or
             Mine
             ,
             which
             carries
             it
             away
             to
             the
             second
             Sink
             .
             By
             the
             second
             ●ork
             ,
             the
             Water
             is
             drawn
             out
             of
             the
             second
             Sink
             14
             fathom
             ,
             from
             the
             bottom
             ,
             and
             set
             in
             by
             a
             Level
             to
             the
             third
             Sink
             ,
             which
             being
             only
             12
             fathom
             deep
             ,
             the
             Water-work
             sets
             it
             above
             ground
             .
             The
             form
             of
             the
             Engine
             is
             after
             this
             manner
             .
             In
             the
             first
             Sink
             there
             is
             an
             Outter-wheel
             moved
             ,
             as
             other
             Milns
             are
             ,
             by
             the
             Water
             of
             the
             River
             :
             upon
             the
             end
             of
             the
             Axle-tree
             of
             which
             Wheel
             ,
             there
             is
             a
             Ragg-wheel
             ,
             turning
             vertically
             ,
             as
             doth
             the
             
               Outer-wheel
               ▪
            
             This
             Ragg-wheel
             by
             a
             Nutt
             ,
             or
             Trinle
             turns
             another
             ,
             which
             moves
             horizontally
             ,
             the
             Axle-tree
             whereof
             goes
             right
             down
             in
             the
             Sink
             ,
             and
             may
             be
             is
             8
             or
             10
             fathom
             ;
             at
             the
             end
             whereof
             there
             is
             another
             Ragg
             ,
             which
             by
             a
             Nutt
             turns
             another
             Wheel
             ,
             which
             goes
             vertically
             as
             the
             first
             Ragg
             ,
             and
             causeth
             another
             Wheel
             with
             a
             long
             Axle-tree
             turn
             as
             the
             first
             ,
             and
             so
             down
             till
             it
             come
             to
             the
             Wheel
             ,
             which
             turns
             the
             Axle-tree
             ,
             by
             which
             the
             Chain
             is
             drawn
             .
             The
             second
             Sink
             ,
             hath
             such
             another
             Engine
             ,
             but
             not
             so
             many
             Wheels
             ,
             in
             regard
             it
             is
             not
             so
             deep
             .
             The
             third
             ,
             hath
             only
             one
             
               single
               Wheel
            
             ,
             whereby
             the
             Water
             is
             drawn
             above
             ground
             .
          
           
             The
             most
             curious
             of
             these
             Engines
             ,
             that
             are
             to
             be
             seen
             ,
             are
             at
             Ravensworth
             near
             to
             Newcastle
             ,
             which
             belongs
             to
             Sir
             
               Thomas
               Liddel
            
             ,
             a
             most
             ingenious
             Gentleman
             ,
             who
             ,
             for
             procuring
             a
             Fall
             of
             Water
             ,
             which
             may
             serve
             the
             Wheels
             of
             all
             the
             three
             Sinks
             ,
             hath
             erected
             the
             first
             work
             upon
             Pillars
             like
             a
             Wind-Mill
             ,
             pretty
             high
             above
             ground
             ,
             from
             which
             the
             Water
             falling
             ,
             makes
             the
             second
             go
             closs
             above
             ground
             .
             And
             to
             make
             the
             Water
             fall
             to
             the
             third
             ,
             the
             whole
             Wheel
             is
             made
             go
             within
             the
             surface
             of
             the
             ground
             ,
             which
             terminats
             at
             a
             River
             under
             the
             Works
             ,
             which
             Mine
             
             is
             of
             a
             considerable
             length
             .
             Where
             Water
             cannot
             be
             had
             to
             make
             such
             Works
             go
             ,
             they
             use
             Horse-works
             ,
             but
             not
             w●th
             so
             good
             success
             ,
             being
             more
             chargeable
             ,
             and
             not
             having
             so
             much
             force
             and
             power
             ,
             as
             the
             Water-works
             .
             But
             I
             am
             of
             opinion
             ,
             that
             Wind-works
             might
             serve
             well
             ,
             where
             Water
             cannot
             be
             had
             ;
             and
             when
             no
             Wind
             should
             happen
             to
             blow
             ,
             the
             same
             Works
             might
             be
             supplied
             by
             Horse
             :
             and
             that
             the
             Wind
             ,
             when
             it
             blows
             but
             ordinarily
             ,
             hath
             as
             much
             force
             ,
             as
             so
             much
             Water
             ,
             which
             is
             made
             use
             of
             for
             turning
             such
             Wheels
             ,
             is
             to
             me
             unquestionable
             .
             For
             I
             have
             seen
             in
             Holland
             ,
             a
             Wind-Mill
             ,
             that
             by
             the
             motion
             of
             the
             Outter-wheel
             ,
             caused
             seven
             pair
             of
             Mill-stones
             to
             go
             at
             once
             ,
             besides
             another
             motion
             for
             bringing
             the
             Victual
             from
             the
             ground
             ,
             four
             or
             five
             Stories
             high
             ,
             to
             be
             Grund
             .
             And
             several
             Saw-Mills
             ,
             which
             besides
             six
             or
             seven
             great
             Saws
             ,
             they
             caused
             go
             ,
             did
             by
             another
             motion
             bring
             up
             from
             the
             Water
             great
             Trees
             like
             Ship-Masts
             ,
             to
             be
             fawen
             ,
             and
             placed
             them
             right
             against
             the
             Saw
             ;
             all
             which
             could
             not
             be
             but
             of
             greater
             weight
             ,
             than
             10
             or
             12
             fathom
             of
             Chain
             with
             Buckets
             ,
             or
             Plates
             for
             drawing
             of
             Water
             .
          
           
             But
             to
             return
             ,
             for
             the
             right
             making
             of
             a
             Level
             ,
             the
             true
             hight
             of
             the
             ground
             ,
             where
             the
             Coal
             lyes
             must
             be
             first
             taken
             ,
             that
             it
             may
             be
             known
             ,
             how
             much
             of
             the
             field
             can
             be
             drained
             by
             it
             ;
             which
             must
             be
             done
             ,
             either
             with
             a
             Quadrant
             ,
             or
             with
             an
             Instrument
             made
             express
             .
             Then
             care
             must
             be
             taken
             ,
             to
             take
             the
             lowest
             part
             for
             the
             mouth
             of
             the
             Level
             ,
             that
             the
             field
             can
             afford
             ,
             and
             from
             that
             it
             must
             be
             carried
             in
             a
             straight
             line
             towards
             that
             part
             of
             the
             field
             ,
             where
             the
             Coal
             is
             thought
             to
             be
             encountered
             by
             the
             Mine
             .
             In
             working
             whereof
             ,
             two
             things
             are
             in
             a
             special
             manner
             to
             be
             reguarded
             .
             First
             ,
             that
             the
             Level
             be
             wrought
             without
             ascent
             ,
             or
             descent
             :
             the
             best
             way
             for
             trying
             this
             ,
             being
             by
             the
             surface
             
             of
             the
             Water
             passing
             through
             it
             ,
             which
             ought
             to
             be
             as
             little
             moving
             ,
             as
             can
             be
             :
             for
             the
             loss
             of
             one
             foot
             of
             Level
             ,
             which
             the
             ground
             gives
             ,
             is
             a
             loss
             of
             a
             considerab●e
             parcel
             of
             Coal
             to
             be
             digged
             ,
             especially
             if
             it
             be
             flate
             .
             It
             there
             occur
             any
             Metals
             ,
             which
             are
             impregnable
             ,
             in
             the
             course
             of
             the
             Level
             ,
             so
             that
             it
             is
             impossible
             ,
             to
             follow
             so
             straight
             a
             line
             ,
             in
             regard
             the
             Mine
             must
             be
             wrought
             over
             the
             top
             of
             that
             stone
             ,
             which
             is
             unworkable
             ,
             in
             that
             case
             ,
             there
             is
             but
             one
             of
             two
             to
             serve
             the
             loss
             of
             Level
             ;
             either
             the
             Coal
             rises
             i●
             Streek
             towards
             which
             the
             Mine
             is
             carried
             ,
             and
             if
             that
             be
             ,
             then
             after
             that
             stone
             is
             past
             ,
             the
             Level
             must
             be
             carried
             ,
             as
             low
             ,
             as
             it
             was
             before
             it
             encountered
             the
             same
             ,
             and
             the
             course
             of
             the
             Water
             shall
             not
             be
             obstructed
             ,
             because
             the
             sourse
             ,
             viz.
             the
             Coal
             from
             whence
             the
             Water
             comes
             ,
             rising
             higher
             than
             the
             Stone
             ,
             the
             Water
             shall
             easily
             pass
             over
             that
             hight
             .
             Hence
             it
             is
             ,
             that
             we
             see
             in
             some
             Coals
             ,
             that
             have
             been
             wrought
             ,
             at
             the
             lowest
             point
             of
             their
             Streek
             by
             a
             drawing-sink
             ,
             and
             the
             Streek
             rising
             from
             that
             point
             ,
             the
             Water
             that
             hath
             come
             off
             the
             Coal
             ,
             being
             in
             its
             Sourse
             higher
             ,
             than
             the
             mouth
             of
             that
             drawing-sink
             ,
             hath
             mad●
             it
             to
             over-run
             ,
             and
             serve
             to
             discharge
             all
             the
             Water
             ,
             that
             comes
             therefrom
             .
             But
             ,
             if
             the
             Mine
             be
             run
             to
             a
             Coal
             ,
             that
             after
             it
             hath
             overtaken
             it
             ,
             rises
             no
             higher
             in
             Streek
             ,
             than
             the
             Mine
             it self
             ,
             the
             Water
             that
             comes
             from
             it
             ,
             will
             not
             pass
             over
             any
             hight
             in
             its
             way
             ,
             but
             will
             be
             unquestionably
             stopped
             .
             Therefore
             ,
             in
             case
             such
             an
             impediment
             could
             not
             be
             removed
             ,
             as
             many
             times
             such
             Metals
             will
             fall
             in
             ,
             which
             are
             unworkable
             in
             a
             direct
             line
             ,
             the
             use
             of
             a
             Siph●n
             might
             be
             tried
             ,
             which
             would
             unquestionably
             supply
             the
             loss
             of
             about
             32
             foot
             of
             Level
             ,
             this
             being
             the
             hight
             in
             Perpendicular
             ,
             to
             which
             the
             Pressure
             of
             the
             Air
             ,
             is
             able
             to
             raise
             Water
             up
             thorow
             a
             Siphon
             .
          
           
           
             The
             next
             thing
             to
             be
             observed
             in
             carrying
             on
             of
             Levels
             ,
             are
             the
             Air-holes
             ,
             for
             which
             there
             is
             a
             necessity
             indispensable
             .
             In
             setting
             down
             whereof
             ,
             care
             must
             be
             had
             ,
             that
             they
             be
             not
             directly
             upon
             the
             Mine
             ,
             lest
             rubbish
             falling
             thorow
             from
             above
             ground
             ,
             should
             stop
             ,
             and
             obstruct
             the
             same
             ,
             and
             so
             obstruct
             the
             course
             of
             the
             Water
             ;
             and
             therefore
             it
             's
             better
             they
             be
             set
             down
             at
             a
             side
             ,
             their
             only
             use
             being
             to
             communicate
             fresh
             Air
             to
             the
             Work-men
             ,
             which
             if
             it
             could
             be
             otherwise
             supplied
             (
             as
             I
             think
             it
             not
             utterly
             impossible
             )
             would
             render
             the
             charge
             of
             the
             Coal-works
             a
             great
             deal
             more
             easy
             .
          
           
             Other
             things
             might
             be
             spoken
             to
             of
             Levels
             ,
             as
             that
             some
             run
             with
             the
             course
             of
             Metals
             ,
             they
             pass
             thorow
             ;
             and
             that
             some
             run
             against
             that
             course
             ;
             and
             of
             bringing
             Level
             from
             the
             Dip
             of
             an
             upper-Coal
             ,
             which
             hath
             a
             Level
             of
             its
             own
             ,
             to
             dry
             a
             Coal
             lying
             under
             it
             ,
             which
             cannot
             be
             otherwise
             done
             .
             But
             these
             things
             being
             common
             and
             obvious
             to
             any
             ,
             who
             have
             but
             the
             smallest
             skill
             and
             experience
             ,
             I
             shall
             forbear
             .
          
           
             This
             confused
             account
             ,
             your
             importunity
             hath
             drawen
             from
             me
             ,
             for
             which
             if
             your
             Book
             suffer
             censure
             ,
             which
             I
             grant
             it
             may
             do
             ,
             as
             to
             this
             part
             of
             it
             ,
             you
             are
             to
             blame
             your self
             ,
             and
             so
             I
             rest
             and
             am
             ,
             &c.
             
          
           
             FINIS
             .
          
        
      
    
     
       
         
         
           POSTSCRIPT
           .
        
         
           
             Reader
             ,
          
        
         
           THat
           thou
           mayest
           know
           the
           rise
           ,
           and
           occasion
           of
           this
           Postscript
           ,
           which
           I
           have
           subjoyned
           ,
           I
           shall
           give
           thee
           this
           short
           account
           .
           When
           this
           Book
           was
           first
           committed
           to
           the
           Press
           ,
           I
           sent
           an
           intimation
           thereof
           to
           several
           persons
           ,
           whom
           I
           judged
           would
           encourage
           it
           ,
           yet
           to
           none
           ,
           but
           to
           such
           ,
           in
           whose
           kindness
           I
           had
           confidence
           ,
           and
           whom
           I
           judged
           my
           real
           friends
           .
           Among
           others
           ,
           I
           sent
           over
           to
           Saint
           Andrews
           one
           of
           my
           Edicts
           ,
           to
           one
           or
           two
           there
           ,
           in
           whom
           I
           trusted
           ,
           but
           in
           stead
           of
           a
           kindly
           return
           from
           them
           ,
           to
           whom
           I
           had
           written
           most
           affectionatly
           ,
           they
           wrot
           back
           a
           Letter
           ,
           wherein
           they
           superciliously
           condemn
           the
           purposes
           of
           this
           Book
           ,
           before
           ever
           they
           had
           seen
           them
           ,
           which
           is
           as
           follows
           .
        
         
           
             
               
                 Sir
                 ,
              
            
             
               I
               Received
               yours
               on
               Saturday
               last
               ,
               and
               having
               occasion
               the
               same
               night
               to
               be
               in
               company
               with
               many
               of
               the
               Masters
               of
               the
               University
               ,
               I
               made
               known
               your
               resolution
               to
               them
               ,
               shewing
               them
               your
               Edict
               ,
               and
               desiring
               their
               Contributions
               :
               some
               were
               not
               pleased
               ,
               that
               ye
               call
               the
               Doctrine
               concerning
               the
               weight
               and
               pressure
               of
               the
               Water
               in
               its
               own
               Element
               ,
               new
               ,
               seing
               Archimedes
               hath
               affirmed
               ,
               and
               demonstrated
               in
               his
               Books
               
                 de
                 infidentibus
                 humido
              
               the
               same
               Geometrically
               2000
               years
               ago
               ;
               others
               affirmed
               that
               it
               was
               so
               far
               from
               being
               new
               ,
               that
               they
               would
               undertake
               to
               demonstrat
               the
               event
               of
               any
               of
               all
               your
               Experiments
               à
               priore
               from
               Archimedes
               his
               grounds
               ,
               yea
               ,
               in
               general
               of
               any
               Hydrostatical
               Experiment
               ,
               seing
               they
               look
               upon
               it
               ,
               
                 as
                 a
                 Science
                 long
                 ago
                 perfected
                 .
              
               Some
               said
               ,
               as
               to
               Diving
               ,
               that
               they
               imagined
               any
               method
               better
               then
               that
               of
               Melgims
               ,
               which
               is
               now
               v●lgar
               ,
               to
               be
               impossible
               .
               As
               to
               the
               Observation
               of
               the
               Sun
               ,
               or
               Moons
               motion
               in
               a
               second
               
               of
               time
               ,
               yea
               ,
               or
               much
               less
               ,
               it
               can
               be
               done
               most
               exactly
               by
               a
               Telescope
               ,
               and
               a
               Pendulum
               ,
               but
               serves
               to
               no
               purpose
               ,
               seing
               that
               same
               motion
               can
               be
               had
               infinitly
               more
               exact
               by
               preportion
               ,
               from
               observations
               of
               a
               considerable
               interval
               ;
               for
               so
               the
               Astronomers
               collect
               all
               the
               mi●dle
               motions
               of
               the
               Planets
               .
               As
               for
               the
               Observations
               of
               Coal-sinks
               ,
               latitude
               of
               Edinburgh
               ,
               and
               its
               variation
               of
               the
               Needle
               ,
               they
               may
               assuredly
               increase
               the
               Historical
               part
               of
               Learning
               :
               yet
               many
               of
               the
               Masters
               here
               imagine
               themselves
               concerned
               in
               credit
               not
               to
               promote
               the
               publication
               of
               any
               thing
               ,
               which
               seemeth
               to
               declare
               our
               Nation
               ignorant
               (
               by
               calling
               them
               new
               ,
               and
               unheard
               of
               )
               of
               these
               things
               known
               over
               all
               the
               World
               these
               many
               years
               among
               really
               Learned
               Men
               ,
               albeit
               they
               be
               debated
               amongst
               ridiculous
               Monkish
               Philosophers
               .
               I
               conceive
               ,
               ye
               would
               do
               best
               to
               undeceive
               this
               University
               ,
               by
               sending
               us
               some
               of
               your
               most
               abstruse
               Theorems
               ,
               and
               surprizing
               Experiments
               ;
               which
               if
               they
               be
               not
               evidently
               and
               clearly
               deduceable
               from
               Archimedes
               ,
               or
               Stevinus
               ,
               who
               did
               write
               long
               ago
               ,
               or
               rather
               ,
               if
               they
               be
               not
               the
               same
               with
               theirs
               :
               ye
               may
               assure
               your self
               that
               this
               University
               will
               take
               away
               at
               least
               all
               the
               obligations
               ye
               have
               sent
               here
               ;
               otherwayes
               ,
               I
               am
               afraid
               ,
               I
               shall
               not
               be
               able
               to
               prevail
               with
               them
               .
               I
               hope
               ye
               will
               pardon
               this
               my
               freedom
               I
               use
               with
               you
               ,
               and
               return
               an
               answer
               with
               the
               first
               occasion
               ,
               to
            
             
               
                 St.
                 Andrews
                 ,
                 
                   Decemb
                   .
                   27
                   ,
                   1671.
                   
                
              
               
                 Sir
                 ,
              
               
                 Your
                 most
                 humble
                 Servant
                 .
              
            
          
        
         
           After
           the
           receit
           of
           this
           ,
           being
           unwilling
           to
           make
           it
           a
           ground
           of
           debate
           ,
           I
           returned
           a
           most
           discreet
           answer
           ,
           thinking
           to
           conquer
           their
           humour
           with
           civility
           ,
           and
           kindness
           ,
           but
           not
           long
           after
           ,
           hearing
           of
           their
           clamour
           against
           the
           Intimation
           ,
           and
           of
           their
           disswading
           others
           ,
           who
           would
           willingly
           (
           I
           suppose
           )
           have
           condescended
           ,
           I
           was
           necessitated
           to
           send
           this
           return
           ,
           for
           a
           joynt
           answer
           to
           them
           both
           ,
           for
           besides
           this
           ,
           another
           of
           the
           same
           kind
           came
           also
           ,
           of
           which
           hereafter
           .
        
         
           
             
             
               
                 Sir
                 ,
              
            
             
               I
               Received
               yours
               ,
               of
               the
               Date
               of
               December
               27.
               
               167●
               .
               and
               though
               it
               was
               a
               little
               unpleasant
               ,
               yet
               I
               took
               it
               very
               kindly
               from
               〈…〉
               from
               a
               person
               I
               judged
               ingenuous
               ,
               as
               my
               return
               of
               January
               9.
               1672.
               
               〈◊〉
               witness
               ,
               wherein
               I
               did
               not
               in
               the
               least
               resent
               any
               thing
               you
               wrot
               ;
               neither
               would
               I
               ever
               have
               done
               ,
               if
               you
               ,
               and
               some
               others
               especially
               with
               you
               ,
               had
               not
               proclaimed
               publickly
               ,
               what
               you
               and
               they
               had
               written
               to
               me
               privatly
               ,
               the
               noise
               whereof
               ,
               I
               have
               heard
               here
               ,
               by
               several
               persons
               who
               came
               from
               the
               place
               .
               Therefore
               ,
               Sir
               ,
               you
               must
               pardon
               me
               ,
               if
               now
               at
               last
               ,
               after
               so
               much
               silence
               ,
               I
               return
               you
               this
               answer
               ,
               for
               no
               other
               end
               ,
               but
               for
               my
               own
               vindication
               ,
               in
               what
               I
               have
               lately
               Printed
               ,
               and
               am
               about
               to
               Print
               .
               I
               am
               very
               much
               then
               surprized
               with
               the
               answer
               ,
               that●
               you
               and
               they
               have
               returned
               ,
               such
               a
               rank
               smell
               of
               preju●i●e
               and
               envy
               ,
               I
               find
               in
               it
               .
               I
               am
               rewarded
               evil
               for
               good
               ;
               for
               I
               minded
               nothing
               but
               good-will
               ;
               else
               ,
               you
               and
               they
               should
               never
               have
               been
               troubled
               with
               my
               proposal
               .
               If
               they
               had
               affected
               the
               reputation
               of
               Learning
               ,
               there
               was
               another
               way
               to
               it
               ,
               then
               the
               course
               they
               have
               taken
               ;
               namely
               to
               condemn
               with
               such
               a
               deal
               of
               superciliousness
               ,
               as
               derogatory
               to
               the
               credit
               of
               the
               Nation
               ,
               forsooth
               ,
               the
               labours
               of
               one
               ,
               that
               hath
               done
               mor●
               for
               the
               credit
               thereof
               ,
               then
               they
               have
               done
               as
               yet
               .
               They
               might
               have
               minded
               the
               saying
               of
               the
               grave
               Historian
               ,
               
                 Nam
                 famam
                 atque
                 gloriam
                 ,
                 Bonus
                 atque
                 ignavus
                 aeque
                 sibi
                 exoptant
                 :
                 ille
                 verâ
                 viâ
                 n●titur
                 ,
                 huic
                 ,
                 quia
                 Bonae
                 ●tt●s
                 desunt
                 ;
                 dolis
                 atque
                 fallaciis
                 contendit
                 .
              
               And
               for
               undeceiving
               of
               the
               University
               ,
               as
               I
               am
               very
               far
               from
               counting
               such
               persons
               the
               University
               ,
               so
               have
               I
               more
               respect
               for
               it
               ,
               and
               all
               Learned
               Persons
               in
               it
               ,
               then
               to
               account
               their
               deed
               ,
               the
               deed
               of
               the
               University
               .
               As
               for
               what
               they
               can
               do
               ;
               for
               promitting
               the
               work
               I
               have
               now
               at
               the
               Press
               ,
               I
               value
               it
               not
               at
               the
               rate
               of
               shewing
               them
               so
               much
               as
               one
               of
               my
               The●rems
               :
               for
               ,
               if
               they
               have
               ●narled
               so
               much
               ,
               〈◊〉
               but
               at
               one
               word
               ,
               in
               the
               intimation
               of
               the
               work
               ;
               what
               would
               they
               do
               ,
               if
               they
               had
               more
               of
               it
               ?
               which
               yet
               must
               stand
               firm
               ,
               unless
               they
               (
               for
               't
               is
               a
               matter
               of
               fact
               ,
               and
               cannot
               be
               contradicted
               with
               Sophistry
               and
               Non-sense
               )
               overthrow
               it
               ,
               which
               I
               little
               fear
               ,
               as
               Cicero
               did
               
                 Verres
                 ,
                 Tab●l●s
                 &
                 Testibus
                 ad
                 singula
                 indicia
                 prolatis
                 .
              
               Neither
               will
               their
               imagination
               do
               it
               ,
               for
               that
               cannot
               make
               
                 factum
                 infectum
              
               .
               
               It
               seemeth
               to
               be
               a
               great
               weight
               ,
               that
               they
               lay
               upon
               the
               force
               of
               their
               imagination
               ,
               since
               they
               are
               so
               confident
               ,
               as
               to
               say
               ,
               they
               imagine
               any
               method
               of
               Diving
               better
               then
               that
               of
               Melgims
               ,
               to
               be
               impossible
               ,
               
                 adeo
                 familiare
                 est
                 hominibus
                 supra
                 vires
                 humanas
                 credere
                 ,
                 quicquid
                 supra
                 illorum
                 captum
                 sit
                 .
              
               As
               for
               these
               others
               ,
               that
               would
               demonstrat
               à
               priori
               ,
               the
               event
               of
               all
               my
               Experiments
               from
               the
               grounds
               of
               Archimedes
               ,
               as
               I
               doubt
               not
               ,
               but
               they
               would
               ,
               if
               they
               could
               ,
               so
               in
               this
               they
               bewray
               their
               want
               of
               skill
               :
               for
               Archimedes
               wanted
               a
               necessary
               requisite
               ,
               which
               I
               go
               upon
               for
               my
               deductions
               .
               And
               though
               it
               were
               true
               (
               which
               they
               say
               )
               that
               all
               my
               Theorems
               were
               demonstrable
               
                 à
                 priori
              
               from
               the
               grounds
               of
               Archimedes
               ,
               yet
               this
               doth
               not
               hinder
               them
               to
               be
               both
               new
               ,
               and
               un-heard-of
               ,
               as
               if
               new
               ,
               and
               un-heard-of
               conclusions
               ,
               might
               not
               be
               deduced
               from
               old
               principles
               .
               In
               this
               they
               are
               so
               much
               the
               better
               ,
               and
               not
               the
               worse
               .
               And
               whereas
               they
               say
               ,
               they
               look
               upon
               the
               Hydrostaticks
               ,
               as
               a
               Science
               long
               since
               perfected
               ,
               in
               this
               they
               do
               yet
               more
               discover
               their
               weakness
               :
               for
               what
               one
               Science
               hath
               yet
               come
               to
               its
               perfection
               ?
               Nay
               ,
               hath
               not
               this
               Pedantick
               humour
               been
               the
               great
               bane
               of
               good
               Learning
               ,
               that
               Sciences
               were
               already
               perfected
               ?
               So
               that
               Se●eca
               said
               truly
               ,
               
                 Puto
                 multos
                 pervenire
                 potuisse
                 ad
                 sapientiam
                 ,
                 nisi
                 putassent
                 se
                 pervenisse
                 .
              
               As
               for
               the
               representing
               of
               the
               Sun
               or
               Moons
               motion
               
                 to
                 the
                 eye
              
               (
               ●or
               that
               should
               surely
               hav●
               been
               taken
               in
               )
               that
               you
               say
               ,
               serveth
               to
               no
               purpose
               ,
               to
               me
               is
               a
               little
               uncouth
               ,
               considering
               how
               much
               it
               conduceth
               to
               the
               accuracy
               of
               Astronomical
               Observations
               ,
               beyond
               what
               the
               former
               Ages
               could
               attain
               to
               .
               And
               whereas
               you
               say
               ,
               it
               can
               be
               had
               infinitly
               more
               exactly
               by
               Observations
               of
               a
               considerable
               interval
               ,
               as
               Astronomers
               collect
               all
               the
               middle
               motions
               of
               the
               Planets
               ,
               but
               I
               say
               ,
               even
               those
               intervals
               should
               have
               been
               far
               better
               known
               ,
               if
               they
               had
               by
               this
               mean
               ,
               and
               the
               
                 Oscillatory
                 Clock
              
               been
               observed
               ;
               so
               whatever
               arguing
               by
               the
               rule
               of
               proportion
               ,
               may
               do
               for
               shewing
               the
               Suns
               motion
               in
               seconds
               ,
               and
               thirds
               ,
               it
               reacheth
               not
               these
               accuracies
               ,
               that
               are
               reached
               by
               this
               inv●ntion
               ,
               so
               long
               as
               the
               Sense
               cannot
               deprehend
               ,
               and
               six
               them
               .
               As
               for
               the
               Observations
               of
               
                 Coal-sinks
                 ,
                 &c.
              
               which
               you
               say
               ,
               may
               assuredly
               increase
               the
               Historical
               part
               of
               Learning
               ;
               are
               they
               not
               for
               this
               the
               more
               useful
               ,
               since
               the
               Scientifical
               part
               of
               Learning
               dependeth
               so
               much
               on
               the
               Historical
               part
               ,
               and
               which
               conduceth
               more
               thereto
               ,
               then
               all
               the
               precario●s
               
               principles
               of
               
                 Cartesius
                 ,
                 Epicurus
              
               ,
               and
               the
               like
               ;
               who
               in
               stead
               of
               giving
               us
               an
               account
               of
               the
               World
               that
               God
               made
               ,
               have
               given
               us
               imaginary
               ones
               of
               their
               own
               making
               :
               so
               that
               such
               a
               History
               ,
               as
               
                 Natural
                 Philosophy
              
               requires
               ,
               is
               wisely
               accounted
               among
               the
               desiderata
               in
               Learning
               by
               all
               sound
               Philosophers
               to
               this
               day
               .
               So
               much
               in
               answer
               to
               yours
               ,
               and
               I
               rest
            
             
               
                 Edinburgh
                 ,
                 
                   Feb.
                   22.
                   1672.
                   
                
              
               
                 Your
                 Servant
                 .
              
            
          
        
         
           IN
           answer
           to
           this
           last
           ,
           there
           came
           to
           my
           hands
           from
           
             St.
             Andrews
          
           a
           Letter
           unsubscribed
           by
           any
           Master
           ,
           full
           of
           barbarous
           railings
           ,
           passing
           all
           bounds
           of
           civility
           ,
           against
           my self
           ,
           friends
           ,
           and
           works
           ,
           which
           ,
           if
           the
           Contrivers
           had
           not
           been
           more
           gall'd
           with
           reason
           ,
           then
           injuries
           ,
           I
           suppose
           they
           would
           have
           forborn
           .
           And
           thinking
           this
           not
           sufficient
           ,
           they
           would
           needs
           aggravate
           the
           wrong
           ,
           by
           one
           circumstance
           more
           ,
           which
           they
           either
           did
           out
           of
           disdain
           ,
           or
           fear
           ,
           not
           daring
           to
           own
           what
           they
           had
           contrived
           ,
           in
           making
           the
           Bedale
           of
           the
           University
           subscribe
           it
           .
           And
           to
           give
           a
           further
           proof
           of
           their
           insatiable
           malice
           ,
           they
           must
           needs
           distribute
           copies
           thereof
           ,
           as
           glorying
           in
           their
           shame
           ,
           one
           whereof
           was
           sent
           over
           to
           Edinburgh
           unsubscribed
           also
           .
           Now
           ,
           let
           any
           indifferent
           person
           judge
           ,
           whether
           or
           not
           ,
           I
           have
           not
           reason
           to
           do
           what
           I
           have
           done
           .
           They
           have
           been
           the
           first
           proclaimers
           ,
           though
           in
           a
           clandestine
           way
           ,
           and
           why
           not
           I
           next
           ,
           in
           this
           way
           .
           But
           lest
           ,
           they
           think
           ,
           they
           have
           marred
           as
           much
           the
           tranquillity
           of
           my
           mind
           therewith
           ,
           as
           they
           have
           their
           own
           .
           I
           shall
           answer
           in
           the
           words
           of
           the
           Moralist
           ,
           
             Eleganter
             Demetrius
             noster
             solet
             dicere
             ,
             eodem
             loco
             sibi
             esse
             voces
             imperitorum
             ,
             qu●ventre
             redditos
             crepitus
             .
             Quid
             enim
             inquit
             ,
             mea
             refert
             ,
             sursu●
             isti
             ,
             five
             deorsum
             sonent
             .
          
           And
           let
           this
           stand
           ,
           for
           the
           railing
           par●
           of
           the
           letter
           .
        
         
           But
           first
           ,
           whereas
           he
           should
           have
           spoken
           to
           the
           contents
           of
           thi●
           Book
           ,
           he
           falleth
           foul
           upon
           my
           last
           Peice
           ,
           intituled
           ,
           
             Ars
             nova
             ,
             &
             magna
             ,
             gravitatis
             ,
             &
             levitatis
             ,
          
           snarling
           eight
           or
           nine
           times
           ,
           at
           th●
           bare
           title
           ,
           like
           a
           C●r
           at
           the
           horse
           heels
           ,
           when
           he
           cannot
           reach
           th●
           rider
           .
           This
           lay
           not
           in
           his
           way
           ,
           doing
           herein
           like
           Vejento
           the
           blin●
           
           Courtier
           of
           Domitian
           ,
           who
           ,
           when
           he
           should
           have
           turned
           his
           face
           to
           the
           right
           hand
           ,
           where
           the
           Sturgeon
           lay
           ,
           turned
           it
           to
           the
           left
           .
        
         
           
             —
             Nam
             plurima
             dixit
          
           
             In
             laevam
             conversus
             :
             at
             illi
             dextra
             jacebat
          
           
             Bellu●
             .
          
        
         
           So
           that
           concerning
           all
           these
           invectives
           ,
           I
           may
           say
           ,
           
             sed
             quid
             ha●
             ad
             Rhombum
          
           .
           But
           what
           other
           can
           be
           expected
           ,
           
             ubi
             furor
             arma
             ministrat
          
           .
           But
           seing
           his
           Letter
           shews
           ,
           how
           sick
           he
           is
           of
           the
           plague
           of
           malice
           ,
           and
           envy
           ,
           I
           am
           so
           far
           from
           storming
           at
           him
           ,
           that
           I
           pit●
           him
           ,
           though
           he
           may
           be
           a
           Master
           ,
           and
           teacher
           of
           others
           ,
           and
           wish
           him
           to
           teach
           himself
           .
        
         
           
             —
             Servitium
             acre
          
           
             Te
             nihil
             impellit
             ?
             nec
             quicquam
             extrinsecus
             intrat
          
           
             Quod
             nervos
             agitet
             ?
             Sed
             si
             intus
             &
             jecore
             agro
          
           
             Nafcantur
             domini
             ,
             quî
             tu
             impunitior
             exis
          
           
             Atque
             hic
             ,
             quem
             ad
             strigiles
             scutica
             &
             metus
             egit
             herilis
             .
          
        
         
           That
           I
           do
           not
           interpret
           this
           (
           Reader
           )
           excuse
           me
           ,
           for
           I
           am
           speaking
           (
           I
           suppose
           )
           to
           a
           Master
           of
           an
           University
           ,
           and
           a
           gentleman
           too
           ,
           of
           very
           high
           pretences
           ,
           as
           to
           learning
           .
           And
           yet
           I
           cannot
           but
           think
           strange
           of
           two
           things
           .
           F●rst
           ,
           that
           he
           returneth
           not
           the
           least
           Latine
           sentence
           in
           answer
           to
           mine
           ,
           no
           not
           so
           much
           as
           pertinent
           language
           in
           his
           Mother-tongue
           .
           What
           ?
           An
           Universityman
           ,
           and
           no
           return
           in
           Latine
           to
           these
           sayings
           ,
           of
           so
           grave
           Authors
           ,
           or
           at
           least
           in
           pertinent
           English.
           The
           other
           ,
           that
           he
           no
           more
           understands
           ,
           these
           words
           ,
           
             as
             Cicero
             did
             Verres
             ,
             tabulis
             &
             testibus
             ad
             singula
             indicia
             prolatis
             ,
          
           than
           the
           Curat
           did
           the
           
             Modicum
             bonum
          
           that
           he
           was
           desired
           to
           prepare
           for
           the
           Bishops
           dinner
           .
           For
           ,
           whereas
           he
           saith
           ,
           
             as
             for
             your
             Latine
             sentences
             ,
             where
             ar
             our
             doli
             ,
             and
             fallaciae
             ,
             tabulae
             &
             testes
             ,
             sapientia
             ad
             quam
             putamus
             nos
             pervenisse
             .
          
           To
           pass
           the
           first
           and
           last
           question
           ,
           of
           which
           anone
           ,
           the
           second
           was
           most
           ●mproper
           for
           him
           to
           ask
           at
           me
           ,
           who
           did
           put
           him
           to
           it
           ,
           to
           overthrow
           the
           title
           of
           my
           Experiments
           ,
           to
           wit
           New
           ,
           not
           by
           Sophitry
           ,
           and
           Non-sense
           ,
           but
           as
           Cicero
           did
           
             Verres
             ,
             tabulis
             &
             testibus
          
           ,
           ●y
           proof
           and
           Witnesses
           ;
           this
           he
           should
           not
           have
           asked
           ,
           but
           an●wered
           .
           I
           am
           confident
           a
           Boy
           in
           the
           second
           Class
           ,
           could
           better
           ●ave
           understood
           these
           words
           ,
           than
           this
           man.
           And
           for
           the
           first
           ●uestion
           ,
           
             where
             are
             our
          
           doli
           ,
           and
           fallaciae
           ?
           Why
           should
           he
           ask
           it
           ,
           
           seing
           the
           design
           of
           his
           Letter
           may
           be
           evidently
           seen
           ,
           to
           put
           
             Royal
             Societies
          
           ,
           and
           Universities
           between
           him
           and
           me
           ,
           in
           the
           front
           ,
           whom
           I
           have
           not
           made
           my
           party
           ,
           but
           to
           whom
           I
           owe
           all
           due
           respect
           ;
           and
           such
           a
           poor
           pitiful
           fellow
           as
           the
           Bedale
           in
           the
           Re●r
           ,
           in
           causing
           him
           subscribe
           his
           letter
           thus
           ,
        
         
           March
           14.
           1672.
           
        
         
           Mr.
           
             Patrick
             Mathers
          
           ,
           Arch-bedale
           to
           the
           University
           of
           
             St.
             Andrews
          
           .
        
         
           Is
           not
           this
           to
           do
           ,
           as
           the
           Butcher
           did
           ,
           who
           sought
           his
           knife
           ,
           when
           it
           was
           sticking
           in
           his
           teeth
           .
           If
           the
           University
           ordered
           this
           subscription
           ,
           it
           would
           have
           been
           said
           ,
           
             at
             the
             command
             of
             the
             University
             .
          
           If
           not
           ,
           it
           cannot
           be
           purged
           from
           a
           false
           insinuation
           :
           and
           the
           University
           may
           justly
           resent
           it
           ,
           that
           their
           publick
           servant
           ,
           hath
           been
           so
           abused
           .
           If
           the
           fear
           of
           a
           counterblow
           hath
           made
           him
           afraid
           ,
           to
           put
           his
           hand
           to
           it
           ,
           he
           hath
           done
           as
           the
           Ape
           did
           ,
           that
           thrust
           the
           Cats
           foot
           into
           the
           fire
           ,
           because
           he
           durst
           not
           do
           it
           himself
           ,
           and
           given
           a
           palpable
           discovery
           of
           the
           diffidence
           he
           had
           of
           his
           cause
           .
           If
           he
           hath
           done
           it
           ,
           to
           put
           indignity
           on
           his
           adversary
           ,
           he
           hath
           missed
           his
           mark
           ,
           for
           as
           a
           certain
           Writer
           saith
           well
           ,
           
             Infamy
             is
             as
             it
             is
             received
             .
             If
             thou
             be
             Mud-wall
             it
             will
             stick
             :
             if
             Marble
             it
             will
             rebound
             :
             if
             thou
             storm
             at
             it
             ,
             it
             is
             thine
             :
             if
             thou
             despise
             it
          
           (
           as
           I
           do
           this
           )
           
             it
             is
             his
          
           .
           But
           besides
           this
           ,
           he
           endeavoureth
           to
           put
           Mr.
           
             Iames
             Gregory
          
           between
           him
           and
           me
           also
           ,
           and
           bringeth
           him
           in
           speaking
           of
           my
           writings
           ,
           with
           such
           a
           deal
           of
           disdain
           and
           sauciness
           ,
           
             ut
             nihil
             supra
          
           .
           What
           ?
           was
           Mr.
           
             Iames
             Gregory
          
           such
           an
           eminent
           person
           ,
           that
           he
           could
           not
           speak
           his
           thoughts
           himself
           ,
           but
           needeth
           you
           Sir
           ,
           for
           a
           Proxy
           ,
           and
           Chancellour
           to
           speak
           for
           him
           .
           If
           Mr.
           
             Iames
             Gregory
          
           will
           speak
           to
           me
           ,
           what
           you
           have
           spoken
           in
           his
           name
           ,
           he
           shall
           have
           an
           answer
           ▪
           But
           I
           have
           no
           mind
           to
           gratify
           so
           far
           your
           doli
           ,
           and
           fallacia
           ,
           as
           to
           fall
           on
           any
           man
           upon
           your
           word
           ,
           having
           so
           little
           confidence
           of
           your
           common
           honesty
           .
           This
           were
           
             perversam
             gratiam
             gratificari
          
           .
           Wherefore
           passing
           his
           impertinent
           railings
           ,
           I
           come
           to
           answer
           ,
           what
           he
           hath
           returned
           to
           my
           purposes
           in
           my
           last
           .
           And
           that
           he
           may
           get
           no
           wrong
           ,
           I
           shall
           set
           down
           the
           very
           words
           of
           his
           Letter
           ,
           
             viz
             ;
             〈◊〉
             to
             what
             you
             write
             concerning
             the
             imperfections
             of
             Sciences
             :
             the
             Scientifical
             pairt
             of
             Geographie
             is
             so
             perfected
             ,
             that
             there
             is
             nothing
             required
             
             for
             the
             projection
             ,
             description
             ,
             and
             situation
             of
             a
             place
             ,
             which
             cannot
             be
             done
             ,
             and
             demonstrat
             .
          
           The
           truth
           is
           they
           have
           overshot
           themselves
           in
           this
           ,
           though
           they
           be
           ashamed
           to
           acknowledge
           so
           much
           ;
           for
           what
           a
           pitiful
           shift
           is
           it
           ,
           to
           bring
           Geography
           for
           an
           instance
           of
           a
           perfected
           Science
           ,
           when
           so
           much
           of
           the
           Earth
           remains
           to
           this
           day
           unknown
           altogether
           ,
           as
           the
           
             Universal
             Mapps
          
           testify
           .
           Of
           the
           known
           parts
           ,
           how
           little
           is
           there
           to
           this
           day
           sufficiently
           described
           by
           the
           exactest
           Mapps
           ,
           that
           time
           ,
           and
           labours
           of
           men
           have
           yet
           produced
           .
           And
           now
           to
           retort
           your
           own
           question
           upon
           your self
           ,
           
             ubi
             est
             sapientia
             ad
             quam
             putatis
             vos
             pervenisse
             ?
          
           O
           but
           saith
           the
           Author
           ,
           
             it
             is
             perfected
             as
             to
             its
             scientifical
             part
             .
          
           But
           I
           pray
           you
           Sir
           ,
           what
           is
           this
           ,
           though
           you
           may
           be
           a
           teacher
           of
           Logick
           of
           no
           small
           esteem
           with
           your self
           ,
           and
           disdain
           of
           others
           ,
           but
           to
           play
           the
           Sophister
           ,
           by
           the
           
             Fallacy
             ,
             à
             dicto
             secundum
             quid
             ,
             ad
             dictum
             simpliciter
             :
             Geography
             is
             perfected
             as
             to
             its
             scientifical
             part
             ,
             therefore
             it
             may
             be
             called
             a
             perfected
             Science
             ,
          
           when
           it
           is
           so
           defective
           as
           to
           the
           
             Historical
             part
          
           .
           If
           Astronomy
           to
           this
           day
           be
           a
           Science
           not
           perfected
           ,
           through
           want
           of
           its
           
             Historical
             part
          
           ,
           shall
           not
           Geography
           be
           so
           likewise
           .
           But
           furder
           Sir
           ,
           for
           the
           
             Scientif●cal
             part
          
           of
           Geography
           ,
           which
           you
           alledge
           to
           be
           perfected
           ,
           in
           this
           also
           you
           argue
           against
           the
           rules
           of
           Logick
           ,
           in
           committing
           that
           same
           Fallacy
           over
           again
           ,
           for
           giving
           and
           not
           granting
           what
           you
           say
           ,
           that
           the
           
             Scientifical
             part
             of
             Geography
          
           were
           perfected
           ,
           as
           to
           the
           
             projection
             ,
             description
             ,
             and
             situation
          
           of
           a
           place
           ,
           is
           it
           for
           this
           perfected
           as
           to
           the
           
             Scientifical
             part
             simpliciter
          
           ,
           which
           you
           are
           obliged
           to
           prove
           ,
           else
           you
           say
           nothing
           to
           the
           purpose
           .
           And
           what
           I
           pray
           you
           ,
           is
           that
           poor
           alleadgence
           you
           make
           ,
           in
           comparison
           of
           these
           things
           ,
           wherein
           Geography
           is
           defective
           ,
           even
           as
           to
           the
           
             Scientifical
             part
          
           ?
           Who
           hath
           spoken
           yet
           sufficiently
           to
           the
           surface
           ,
           and
           hight
           of
           the
           Sea
           above
           the
           Earth
           ,
           the
           hight
           of
           the
           Hills
           ,
           and
           
             Mountains
             ,
             Longitude
          
           of
           places
           ,
           nay
           the
           circumference
           of
           the
           Earth
           it self
           ?
           Answer
           this
           question
           ,
           if
           you
           can
           ,
           
             Hast
             thou
             perceived
             the
             breadth
             of
             the
             earth
             ,
             declare
             if
             thou
             knowest
             it
             all
             ?
          
           Job
           .
           38.
           18.
           
           And
           now
           Sir
           ,
           I
           must
           put
           you
           to
           it
           again
           ,
           
             ubi
             est
             sapientia
             ad
             quam
             putatis
             vos
             perverisse
             .
          
        
         
           His
           next
           answer
           runneth
           thus
           ,
           
             The
             Scientifical
             part
             of
             the
             Opticks
             is
             so
             perfected
             ,
             that
             nothing
             can
             be
             required
             for
             the
             perfection
             of
             the
             
             sight
             ,
             which
             is
             not
             demonstrat
             ,
             albeit
             mens
             hands
             cannot
             reach
             it
             .
             And
             these
             being
             the
             objects
             ,
             of
             the
             foresaid
             Sciences
          
           (
           you
           should
           Sir
           ,
           have
           said
           ,
           the
           whole
           objects
           of
           the
           foresaid
           Sciences
           ,
           else
           you
           still
           play
           the
           Sophister
           )
           
             your
             authority
             shall
             not
             perswade
             him
             ,
             or
             us
             ,
             that
             it
             is
             altogether
             improper
             to
             call
             them
             perfect
             .
          
           But
           mark
           Reader
           ,
           how
           the
           force
           of
           reason
           maketh
           these
           Authors
           to
           succumb●
           for
           whereas
           they
           should
           have
           said
           ,
           
             that
             it
             is
             not
             improper
             to
             call
             them
             perfect
             ,
          
           they
           qualify
           it
           thus
           ,
           it
           is
           not
           altogether
           improper
           .
           And
           again
           ,
           
             your
             authority
             shall
             not
             perswade
             us
             ,
             that
             it
             is
             altogether
             improper
             .
          
           But
           (
           
             my
             Masters
          
           )
           I
           do
           not
           crave
           that
           my
           authority
           may
           perswade
           you
           ,
           but
           reason
           .
           Wherefore
           to
           return
           :
           
             the
             Scientifical
             part
             of
             the
             Opticks
          
           (
           say
           they
           )
           
             is
             so
             perfected
             ,
             that
             nothing
             can
             be
             required
             for
             the
             perfection
             of
             the
             sight
             ,
             which
             is
             not
             demonstrat
             ,
             albeit
             mens
             hands
             cannot
             reach
             it
             .
          
           But
           where
           Sir
           ,
           and
           by
           what
           person
           is
           this
           done
           ?
           Shew
           me
           the
           man
           ,
           (
           if
           you
           can
           )
           that
           hath
           done
           it
           .
           But
           though
           all
           this
           were
           true
           ,
           were
           therefore
           ,
           either
           the
           
             Opticks
             ,
             Dioptricks
             ,
             or
             Catoptricks
          
           perfected
           Sciences
           ?
           Who
           hath
           yet
           sufficiently
           explained
           the
           manner
           
             how
             we
             see
          
           ,
           far
           less
           how
           Birds
           ,
           and
           
             Fishes
             ,
             Beasts
          
           ,
           and
           Insects
           see
           ?
           How
           the
           Eagle
           mounting
           aloft
           spyeth
           her
           prey
           from
           a
           far
           .
           Who
           hath
           spoken
           sufficiently
           to
           the
           nature
           of
           colours
           ?
           For
           these
           also
           belong
           to
           the
           Opticks
           ,
           or
           of
           light
           ,
           and
           of
           the
           infraction
           ,
           and
           refraction
           thereof
           .
           The
           learned
           
             Lord
             Verulam
          
           was
           not
           of
           your
           mind
           Sir
           ,
           when
           he
           wrot
           thus
           ,
           
             De
             forma
             lucis
             ,
             quod
             non
             debita
             〈◊〉
             facta
             fuerit
             inquisitio
             (
             praeserti●●
             cum
             in
             Perspectivâ
             strenuè
             elabor●nt
             homines
             )
             stupenda
             quaedam
             negligentia
             censeri
             possit
             .
             Etenim
             ,
             nec
             in
             perspectivâ
             ,
             nec
             aliàs
             ,
             aliquid
             de
             luce
             ,
             quod
             valeat
             ,
             inquisitum
             est
             .
          
        
         
           If
           Mr.
           Newton
           has
           been
           of
           this
           Authors
           mind
           ,
           he
           should
           not
           have
           attempted
           the
           late
           invention
           of
           his
           
             Span-long
             Dioptrical-catoptrical
             Prospect
          
           ,
           whereby
           Iupiter
           his
           Satellites
           ,
           and
           
             Venus
             horned
          
           are
           to
           be
           seen
           .
           And
           if
           Mr.
           Hook
           ,
           had
           been
           of
           his
           mind
           ,
           he
           should
           not
           have
           made
           his
           late
           Proposal
           of
           
             Telescopes
             ,
             Microscopes
             ,
             Scotoscopes
          
           ,
           by
           figures
           as
           easily
           made
           ,
           as
           those
           that
           are
           plain
           and
           spherical
           ,
           whereby
           the
           light
           ,
           and
           Magnitude
           of
           Objects
           ,
           may
           be
           prodigio●sly
           increased
           ,
           and
           whatsoever
           else
           hath
           hitherto
           been
           attempted
           ,
           or
           almost
           desired
           in
           Dioptricks
           ,
           may
           be
           accomplished
           .
           Where
           observe
           
           (
           Reader
           )
           how
           that
           ingenuous
           person
           ,
           is
           so
           far
           from
           the
           
             windy
             language
          
           of
           this
           Author
           ,
           that
           he
           doth
           not
           say
           ,
           
             whatsoever
             can
             be
             required
             for
             the
             perfection
             of
             sight
             is
             demonstrat
             ,
          
           or
           any
           thing
           like
           it
           ,
           but
           
             whatsoever
             hath
             been
             hitherto
             attempted
             ,
             or
             almost
             desired
             .
          
           For
           who
           can
           tell
           ,
           what
           shall
           be
           found
           out
           hereafter
           ,
           even
           in
           these
           things
           .
           To
           them
           we
           may
           borrow
           the
           words
           of
           the
           Poet
           ,
           
             
               Prudens
               futuri
               temporis
               exitum
            
             
               Caliginosâ
               nocte
               premit
               Deus
               .
            
          
           So
           ,
           Sir
           ,
           I
           still
           put
           you
           to
           that
           question
           ,
           
             Ubi
             est
             sapientia
             ad
             quam
             put
             at
             is
             vos
             pervenisse
             ?
          
        
         
           In
           the
           next
           place
           he
           falleth
           upon
           the
           Hydrostaticks
           ,
           which
           formerly
           he
           looked
           upon
           as
           a
           Science
           perfected
           long
           ago
           .
           But
           because
           in
           his
           answer
           ,
           he
           in
           effect
           yeelds
           the
           cause
           ,
           I
           pursue
           him
           no
           further
           .
           
             Habemus
             confitentem
             reum
          
           ,
           while
           he
           expresly
           grants
           ,
           
             there
             are
             many
             things
             yet
          
           (
           saith
           he
           )
           
             relating
             to
             the
             proportion
             and
             acceleration
             of
             the
             motion
             of
             Fluids
             ,
             which
             are
             yet
             unknown
             .
          
           As
           for
           his
           reflections
           upon
           what
           I
           have
           written
           in
           my
           
             Ars
             Nova
          
           ,
           concerning
           a
           perpetual
           motion
           ,
           which
           I
           never
           intended
           to
           demonstrat
           ,
           I
           leave
           them
           as
           
             indicia
             agri
             &
             impotent
             is
             animi
             .
          
           I
           proceed
           to
           answer
           him
           i●
           what
           he
           addeth
           thus
           .
           
             Only
             we
             cannot
             but
             admire
             your
             simplicity
             in
             this
             ,
             Astronomy
             seeketh
             alwayes
             to
             have
             the
             greatest
             intervalls
             betwix
             observations
             ,
             and
             ye
             take
             that
             ye
             will
             give
             an
             excelle●t
             way
             for
             observing
             the
             Sun
             or
             Moons
             motion
             for
             a
             second
             of
             time
             ,
             that
             is
             to
             say
             ,
             as
             if
             it
             wer
             a
             great
             matter
             ,
             that
             there
             is
             but
             a
             second
             of
             〈◊〉
             betwix
             your
             observations
             .
             I
             wonder
             yow
             say
             the
             eye
             shuld
             be
             added
             ,
             for
             the
             invention
             had
             been
             much
             greater
             had
             that
             been
             away
             .
          
           But
           what
           is
           this
           Sir
           ,
           but
           still
           to
           play
           the
           Sophister
           ?
           Is
           not
           this
           the
           
             S●phism
             ,
             ab
             ignor
             atione
             Elenchi
             ?
          
           for
           it
           doth
           not
           contradict
           my
           conclusion
           ,
           which
           is
           ,
           that
           Astronomical
           Observations
           ,
           by
           this
           mean
           ,
           and
           the
           Oscillatory
           Clock
           ,
           may
           be
           made
           to
           a
           second
           of
           time
           ,
           which
           is
           of
           so
           great
           importance
           in
           Astronomy
           .
           But
           mark
           the
           Non-sense
           (
           Reader
           )
           
             the
             invention
          
           (
           saith
           he
           )
           
             had
             been
             much
             greater
             ,
             if
             the
             eye
             had
             been
             away
             :
          
           that
           is
           ,
           the
           invention
           of
           this
           Observation
           had
           been
           much
           greater
           ,
           if
           the
           eye
           ,
           that
           is
           ,
           the
           Observation
           had
           been
           away
           .
           In
           this
           they
           have
           outshot
           themselves
           also
           ;
           and
           what
           they
           spoke
           
           unadvisedly
           before
           ,
           they
           will
           now
           speak
           deliberatly
           ,
           and
           defend
           it
           rather
           by
           Sophistry
           and
           Non-sense
           ,
           then
           yeeld
           to
           the
           truth
           .
        
         
           Has
           toties
           optata
           exegit
           gloria
           P●ena●
           .
        
         
           The
           Author
           addeth
           ,
           
             None
             will
             denay
             but
             tha●
             an
             g●id
             history
             of
             nature
             is
             absolutelie
             the
             most
             necessary
             requisite
             thing
             for
             learning
             ,
             yet
             it
             is
             not
             like
             ,
             that
             yow
             are
             fit
             for
             that
             purpose
             ,
             who
             so
             fermelie
             beleeves
             the
             myrakles
             of
             the
             Vest
             ,
             as
             to
             put
             them
             in
             Pre●t
             ,
             and
             recordeth
             the
             semple
             Meridian
             Altitudes
             of
             Comets
             ,
             and
             that
             only
             to
             halfs
             of
             degrees
             ,
             or
             little
             maire
             ,
             as
             worthy
             noticing
             .
          
           If
           it
           were
           needful
           ,
           I
           could
           produce
           the
           passages
           of
           some
           of
           the
           most
           Learned
           Writers
           ,
           of
           these
           last
           times
           ,
           that
           have
           recorded
           the
           like
           .
           Were
           they
           therefore
           unfit
           to
           write
           History
           ?
           A
           person
           of
           this
           Authors
           reading
           and
           learning
           ,
           will
           soon
           find
           them
           out
           .
           If
           he
           do
           it
           not
           ,
           let
           him
           know
           ,
           that
           I
           keep
           them
           for
           a
           reserve
           .
           To
           speak
           nothing
           of
           Aristotle
           ,
           who
           wrot
           a
           Book
           
             〈◊〉
             〈◊〉
             〈◊〉
             〈◊〉
             〈◊〉
          
           ,
           extant
           to
           this
           day
           :
           was
           he
           therefore
           unfit
           to
           write
           his
           
             Natural
             Histories
          
           ?
           Prodigious
           relations
           ,
           when
           the
           memory
           of
           them
           may
           be
           found
           credible
           ,
           and
           maintainable
           ,
           such
           as
           mine
           are
           ,
           ought
           not
           to
           be
           excluded
           from
           a
           
             Natural
             History
          
           ,
           or
           else
           the
           Learned
           Lord
           Verulam
           is
           much
           mistaken
           in
           the
           third
           Aphorism
           of
           his
           
             preparatory
             to
             Natural
             and
             Experimental
             History
             :
          
           Nor
           had
           he
           reason
           to
           carp
           at
           my
           Observations
           of
           the
           Comets
           ,
           as
           long
           as
           he
           made
           none
           himself
           .
           But
           they
           will
           speak
           for
           themselves
           to
           any
           that
           read
           them
           .
           Neither
           need
           they
           him
           for
           a
           
             Common
             Cryer
          
           ,
           either
           to
           commend
           them
           ,
           or
           discommend
           them
           ;
           who
           ,
           when
           I
           was
           at
           these
           Observations
           ,
           he
           possibly
           hath
           not
           been
           so
           well
           exercised
           .
        
         
           He
           sub●oyneth
           ,
           
             However
             if
             yow
             do
             this
             last
             part
             concerning
             Col●inks
             weill
             ,
             and
             all
             the
             rest
             be
             but
             an
          
           Ars
           Magna
           &
           Nova
           :
           
             ye
             may
             come
             to
             gaine
             the
             repute
             of
             being
             more
             fit
             to
             be
             as
             Collie●
             ,
             than
             a
             Skollar
             .
          
           I
           must
           tell
           this
           Pedant
           ,
           that
           a
           Coal-hewer
           is
           a
           more
           useful
           person
           in
           his
           own
           station
           ,
           to
           the
           Countrey
           ,
           than
           he
           is
           ;
           and
           that
           the
           Science
           of
           Coal
           ,
           and
           other
           Minerals
           ,
           is
           far
           beyond
           any
           knowledge
           this
           man
           hath
           ,
           or
           can
           teach
           .
           But
           ,
           my
           Lords
           and
           Gentlemen
           ,
           who
           are
           Coal-Masters
           ,
           mark
           this
           :
           if
           ye
           stand
           to
           the
           judgement
           of
           this
           Pedant
           ,
           though
           ye
           had
           never
           so
           much
           skill
           in
           these
           things
           ,
           ye
           may
           come
           to
           gain
           the
           repute
           of
           being
           more
           fit
           to
           be
           
           Coal-hewers
           ,
           than
           Schollars
           ;
           as
           if
           the
           knowledge
           of
           such
           things
           were
           not
           a
           part
           of
           
             Natural
             Philosophy
          
           .
           It
           seems
           he
           hath
           either
           forgotten
           the
           common
           definition
           ,
           or
           else
           hath
           never
           known
           it
           ,
           that
           
             Physica
             est
             Scientia
             Co●poris
             Naturalis
          
           .
        
         
           He
           sub●oyneth
           ,
           
             Ye
             might
             have
             let
             alane
             the
             precarious
             principles
             ,
             and
             imaginary
             Worlds
             of
          
           Descartes
           ,
           
             till
             yowr
             new
             inventions
             had
             made
             them
             so
             :
             for
             it
             man
             be
             telled
             yow
          
           Descartes
           ,
           
             valued
             the
             History
             of
             Nature
             ,
             as
             much
             as
             any
             experimental
             Philosopher
             ever
             did
             ,
             and
             perfected
             it
             more
             with
             judicious
             Experiments
             ,
             than
             ye
             would
             do
             by
             all
             appearance
             in
             ten
             ages
             .
          
           But
           I
           pray
           you
           ,
           Sir
           ,
           did
           Des-cartes
           ,
           and
           Epicurus
           ,
           and
           the
           like
           ,
           found
           their
           Philosophy
           on
           
             Natural
             History
          
           ,
           and
           not
           rather
           upon
           their
           own
           
             precarious
             principles
          
           :
           and
           therefore
           have
           quite
           missed
           the
           mark
           ,
           and
           method
           ,
           that
           was
           requisite
           for
           the
           advancement
           of
           Learning
           ,
           and
           have
           been
           so
           far
           from
           grasping
           Nature
           ,
           that
           it
           hath
           flowen
           out
           from
           among
           their
           hands
           .
           As
           for
           what
           he
           talketh
           of
           Des-cartes
           ,
           perfecting
           
             Natural
             History
          
           by
           Experiments
           ,
           if
           he
           had
           done
           it
           ,
           as
           the
           Poet
           saith
           in
           another
           sense
           ,
           
             Non
             mihi
             res
             ,
             sed
             me
             rebus
             componere
             conor
             .
          
           he
           had
           done
           right
           .
           But
           when
           he
           took
           pains
           on
           these
           ;
           to
           force
           them
           to
           a
           compliance
           with
           his
           own
           fancies
           ,
           was
           not
           this
           to
           study
           
             Natural
             History
          
           ,
           as
           Hereticks
           do
           the
           Scripture
           ,
           and
           to
           be
           a
           
             Fanatick
             Philosopher
          
           ,
           and
           a
           fit
           Master
           for
           the
           like
           of
           you
           .
           The
           
             Proteus
             of
             Nature
          
           ,
           must
           be
           bound
           with
           stronger
           Chains
           ,
           then
           the
           
             fantastick
             Nugae
             of
             Des-cartes
          
           ,
           before
           he
           will
           tell
           his
           secrets
           .
           The
           vanity
           of
           whose
           method
           may
           be
           seen
           in
           the
           Epicureans
           ,
           who
           having
           laid
           down
           this
           precarious
           principle
           ,
           that
           
             the
             sense
             cannot
             erre
          
           ,
           do
           turn
           themselves
           into
           so
           many
           shapes
           ,
           to
           prove
           
             that
             the
             Sun
             is
             no
             bigger
             than
             a
             blew
             Bonnet
             .
          
        
         
           In
           end
           ,
           after
           he
           hath
           given
           a
           Fling
           at
           my
           labours
           in
           
             Glasgow
             Colledge
          
           ,
           about
           Universale
           ,
           and
           
             Ens
             rationis
          
           ,
           which
           I
           am
           not
           afraid
           he
           shall
           come
           the
           length
           of
           in
           haste
           ,
           for
           ought
           I
           can
           learn
           ,
           he
           falleth
           foul
           upon
           the
           two
           Lines
           I
           cited
           out
           of
           Iuvenal
           ,
           in
           the
           close
           of
           my
           answer
           to
           a
           passage
           in
           a
           
             Philosophical
             Transaction
          
           :
           the
           Lines
           are
           .
           
             
             
               —
               C●jus
               sapientia
               m●nstra●
            
             
               Summos
               posse
               viros
               ,
               magnaque
               exempla
               dat●ros
            
             
               Vervecum
               in
               patriâ
               crassoque
               sub
               aëre
               nasci
               .
            
          
        
         
           Of
           these
           Lines
           ,
           he
           writeth
           thus
           ,
           
             Of
             which
          
           (
           saith
           he
           )
           
             the
             sense
             is
             not
             understood●
             except
             ye
             make
             your self
             the
          
           summus
           vir
           ,
           
             and
             us
             all
          
           Verveces
           .
           
             I
             suppose
             this
             may
             be
             the
             great
             credit
             ,
             that
             ye
             say
             ,
             ye
             have
             laboured
             to
             gain
             to
             your
             Nation
             ,
          
           viz.
           
             to
             get
             us
             all
             the
             honourable
             Title
             of
             Weathers
             .
          
           But
           (
           Reader
           )
           had
           these
           
             Learned
             Clerks
          
           been
           as
           skilful
           in
           
             Rhetorical
             Composition
          
           ,
           and
           Resolution
           ,
           as
           in
           Algebraical
           ,
           they
           would
           not
           have
           made
           such
           an
           Inference
           :
           for
           the
           Argument
           is
           
             à
             minori
             ad
             majus
          
           .
           Nor
           was
           it
           ever
           intended
           for
           another
           end
           .
           As
           for
           the
           
             honourable
             Title
             of
             Wedders
          
           ,
           which
           they
           alledge
           I
           have
           gained
           to
           them
           ,
           I
           cannot
           indeed
           affirm
           it
           ;
           for
           if
           I
           should
           ,
           some
           surely
           would
           judge
           me
           to
           have
           wronged
           them
           as
           much
           in
           this
           ,
           as
           I
           have
           done
           them
           right
           all
           alongs
           .
        
         
           But
           ,
           that
           thou
           mayest
           know
           (
           Reader
           )
           something
           more
           of
           the
           temper
           of
           those
           persons
           I
           have
           to
           do
           with
           in
           this
           matter
           ,
           take
           but
           the
           following
           words
           of
           one
           of
           them
           ,
           as
           they
           are
           transcribed
           out
           of
           a
           Letter
           written
           with
           his
           own
           hand
           to
           me
           ,
           after
           I
           had
           written
           to
           him
           a
           friendly
           Letter
           for
           obtaining
           the
           concurrance
           of
           his
           acquaintance
           for
           advancing
           my
           Book
           ,
           
             And
             they
             promise
          
           (
           to
           wit
           the
           Masters
           promise
           )
           
             ye
             shall
             not
             want
             their
             concurrence
             ,
             whereof
             ye
             may
             be
             sure
             ,
             especially
             having
             here
             your
             friend
          
           Mr.
           Gregory
           ,
           
             your
             Cousin
             ,
             and
             me
             here
             to
             put
             them
             in
             mind
             .
             This
             is
             all
             at
             present
             ,
             from
             ,
             Sir
             ,
             your
             real
             friend
             and
             servant
             .
          
        
         
           Now
           ,
           what
           shall
           be
           thought
           of
           one
           ,
           who
           will
           speak
           so
           fair
           to
           your
           face
           ,
           and
           yet
           cut
           you
           with
           so
           many
           invectives
           behind
           backs
           ,
           let
           any
           man
           judge
           .
        
         
           
             Astutam
             vapido
             servat
             sub
             pectore
             vulpem
          
           
             —
             Hic
             niger
             est
             ,
             hunctu
             Romane
             caveto
             .
          
        
         
           But
           to
           give
           a
           further
           discovery
           of
           him
           ,
           in
           the
           year
           1661
           ,
           a
           certain
           ingenious
           Gentleman
           ,
           that
           had
           not
           been
           bred
           a
           Schollar
           ,
           by
           his
           own
           industry
           advanced
           so
           far
           in
           the
           Mathematicks
           ,
           that
           he
           was
           able
           to
           set
           forth
           an
           Almanack
           ,
           for
           which
           ,
           ingenuous
           and
           ingenious
           men
           should
           have
           commended
           him
           .
           But
           this
           Author
           ,
           with
           another
           ,
           though
           he
           had
           never
           injured
           them
           ,
           and
           without
           advertisement
           ,
           fell
           
           upon
           him
           like
           a
           couple
           of
           Mastives
           ,
           upon
           a
           harmless
           Passenger
           ,
           as
           if
           they
           would
           have
           worried
           him
           in
           his
           reputation
           ,
           in
           a
           Pr●gnostication
           they
           set
           forth
           ,
           rateing
           and
           abusing
           him
           out
           of
           measure
           :
           all
           the
           cause
           being
           some
           alledged
           mistakes
           ,
           they
           thought
           they
           found
           in
           some
           of
           his
           calculations
           ,
           and
           in
           a
           Table
           in
           the
           end
           of
           the
           Almanack
           ,
           which
           he
           calleth
           perpetual
           ,
           and
           which
           they
           say
           ,
           though
           falsly
           ,
           that
           it
           will
           not
           hold
           .
           What
           had
           that
           
             righteous
             man
          
           deserved
           at
           their
           hands
           ,
           to
           be
           so
           abused
           in
           Print
           by
           them
           ?
           But
           that
           the
           desig●
           is
           palpable
           ,
           
             the
             raising
             of
             reputation
             to
             themselves
             ,
             upon
             the
             ruine
             of
             the
             names
             of
             others
             ?
          
           And
           yet
           one
           of
           them
           many
           years
           after
           ,
           was
           necessitat
           ,
           for
           fear
           of
           
             bodily
             harm
          
           ,
           to
           crave
           him
           pardon
           ,
           
             with
             humble
             offer
             to
             his
             knee
             .
          
           In
           the
           Prognostication
           ,
           he
           would
           needs
           play
           the
           Poet
           in
           his
           Chronology
           ,
           which
           the
           person
           whom
           he
           wronged
           ,
           might
           have
           found
           more
           fault
           with
           ,
           with
           better
           reason
           ,
           than
           he
           could
           do
           with
           him
           ,
           for
           his
           Calculations
           .
           What
           a
           stranger
           he
           is
           to
           the
           more
           polished
           part
           of
           Learning
           ,
           for
           all
           his
           high
           pretences
           ,
           these
           Verses
           will
           abundantly
           testify
           ,
           some
           whereof
           follow
           ,
           that
           thou
           mayest
           know
           the
           rest
           ,
           
             Tanquam
             ex
             ungue
             leonem
          
           .
           
             
               Since
               that
               the
               Iulian
               period
               first●began
               .
            
             
               Since
               that
               of
               nought
               the
               Lord
               created
               man.
               
            
          
           He
           should
           have
           said
           ,
           
             Since
             that
             of
             dust
             the
             Lord
             created
             man.
             
          
           He
           addeth
           ,
           
             
               Since
               Israel
               from
               Egypt
               Land
               did
               flee
               .
            
             
               Since
               in
               Canaan
               ,
               he
               made
               Hams
               sons
               to
               die
               .
            
             
               Since
               Romulus
               did
               build
               his
               stately
               Roma
               .
            
             
               Since
               Nabonassar
               ,
               hence
               is
               that
               ancient
               ara
               .
            
             
               Since
               Gregory
               helped
               the
               Calendar
               forlorn
               ,
               &c.
               
            
          
           Mark
           Reader
           :
           these
           Verses
           are
           of
           five
           feet
           ,
           at
           least
           they
           should
           be
           so
           :
           but
           how
           far
           he
           is
           from
           observing
           the
           Precept
           of
           that
           great
           Master
           of
           Poets
           ,
           
             Primum
             ne
             medio
             ,
             medium
             ne
             discrepet
             imo
             .
          
           Will
           appear
           from
           his
           close
           ,
           
             
               Since
               fair
               Lucina
               fulfilled
               the
               Golden
               Number
               .
            
             
               Since
               glistering
               Phoebus
               augmented
               Sundays
               Letter
               .
            
             
               Euge
               Poeta
               .
            
          
        
         
         
           It
           may
           be
           he
           will
           say
           ,
           every
           man
           is
           not
           born
           to
           be
           a
           Poet.
           I
           answer
           ,
           If
           the
           Gentleman
           ,
           whom
           he
           reviled
           ,
           failed
           in
           a
           calculation
           ,
           he
           ought
           to
           have
           been
           born
           with
           ,
           and
           encouraged
           :
           for
           there
           are
           many
           things
           that
           even
           a
           mediocrity
           is
           commendable
           in
           ;
           but
           Poesie
           is
           none
           of
           these
           .
           
             
               —
               Mediocribus
               esse
               Poetis
            
             
               Non
               Dii
               ,
               non
               homines
               ,
               non
               concessere
               Columnae
               .
            
          
           However
           ,
           for
           this
           ,
           he
           may
           assure
           himself
           ,
           that
           
             Perque
             Po●tarum
             n●nquam
             celebrabere
             fastos
             .
          
        
         
           But
           I
           leave
           him
           to
           the
           S●ty●ists
           of
           the
           time
           ,
           
             Quo
             illustrius
             vapulet
          
           ,
           for
           his
           never
           being
           seen
           farder
           in
           Print
           ,
           than
           by
           a
           railing
           Almanack
           ,
           and
           ridiculous
           Verses
           ,
           the
           better
           whereof
           ,
           might
           have
           been
           made
           by
           the
           Laird
           of
           Dysert
           .
        
         
           'T
           is
           like
           this
           Antagonist
           ,
           will
           set
           his
           
             Plumbeous
             Cerebrosity
          
           a
           work
           to
           rifle
           some
           of
           my
           Writings
           ,
           and
           shake
           his
           head
           ,
           when
           he
           is
           put
           to
           a
           demur
           ,
           as
           ever
           a
           man
           did
           a
           bottle
           for
           Sack
           ;
           but
           though
           he
           should
           ,
           and
           I
           have
           nothing
           of
           his
           ,
           but
           an
           old
           Prognostication
           of
           the
           Year
           ,
           1661
           ,
           to
           ripe
           up
           ,
           yet
           who
           knowes
           ,
           but
           I
           may
           meet
           with
           some
           of
           his
           Bajan-notes
           ,
           or
           some
           of
           his
           wonders
           about
           
             Ens
             Rationis
          
           ,
           and
           
             Genus
             Logicae
          
           ,
           that
           he
           is
           now
           sweating
           at
           .
           I
           am
           indeed
           at
           some
           disadvantage
           ,
           while
           he
           only
           letteth
           a
           flisk
           at
           me
           ,
           from
           under
           deck
           .
           Though
           I
           have
           been
           a
           little
           s●ell
           in
           this
           reply
           ,
           yet
           't
           is
           no
           wonder
           ,
           considering
           what
           a
           barbarous
           ,
           and
           uncivil
           Pisle
           I
           met
           with
           ,
           which
           I
           shall
           keep
           for
           a
           reserve
           .
           I
           desire
           to
           live
           peaceably
           with
           all
           men
           .
           Neither
           shall
           I
           be
           soon
           provocked
           ,
           so
           long
           as
           they
           keep
           within
           the
           bounds
           of
           civility
           .
           If
           that
           be
           observed
           ,
           I
           shall
           thank
           them
           ,
           for
           any
           mistake
           they
           shall
           let
           me
           see
           in
           my
           writings
           ,
           if
           done
           with
           reason
           ,
           and
           without
           railing
           .
        
         
           FINIS
           .