Harriet Rigby
Margaret Murivia Story
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Margaret Mervinia Storey.
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THE
SE QUE L
то
MENTORIA;
OR,
The Young Ladies Inftructor:
IN
FAMILIAR CONVERSATIONS,
ON A
Variety of Intereſting Subjects,
1
IN WHICH ARE INTRODUCED,
Lectures on Aftronomy and Natural Philofophy,
Expreffed in Terms ſuited to the Comprehenfion of
JUVENILE READERS;
Being principally intended to enlarge the Ideas,
and inſpire juſt Conceptions of the Deity,
from the Contemplation of the general
Syſtem of the Univerſe.
+
BY ANN MURRY.
London:
PRINTED FOR C. DILLY, IN THE POULTRY.
1799.
་
{
}
なぜこ
​Lou
3-1-43
46891
TO HER ROYAL HIGHNESS
THE PRINCESS AMELIA.
WITH the greateſt Deference and
Refpect, I have the honour to prefent
the Sequel to Mentoria to your Royal
Highneſs's confideration; if my per-
formance fhould obtain your approba-
tion, and in any degree prove conducive
to your inſtruction or amuſement, my
ambition will be amply gratified.
I am perfectly convinced your acquired
accompliſhments and innate amiable qua-
lities, may juftly claim the tribute of
Applaufe; but as Praife is too apt to de-
generate into Adulation, I fhall purfue
the unerring dictates of Simplicity and
Truth, and with the moſt ardent zeal
exhort you to perfevere in the attain-
ment of Knowledge, in every depart-
ment of mental cultivation.
Elevated Rank bears no ſpecific weight
in the Scale of Merit, unleſs it is coun-
terpoiſed by Moral Excellence and In-
tellectual Treafures; let this con dera-
tion
a 2
iv
DEDICATION.
tion excite in your Royal Highneſs an
invariable emulation to Dignify your Il-
lustrious Birth, by the Brilliancy of your
intrinfic Virtues.
Accept, Moft Gracious Princefs, my
fincere wiſhes that you may attain pre-
eminence in every ennobling property
that can inform the Underſtanding, or
refine the Heart; as the means of effect-
ing this important purpoſe, diligently
explore the wonders of Nature, which
will infpire you with implicit reverence
for their Primary Source.
Thefe fublime impreffions cannot fail
to produce in your Royal Highneſs, that
dignity of character and confiftency of
conduct, which will infure Prefent Hap-
pineſs, and entitle you to Future Re-
ward: in the earneſt hope that you may
enjoy theſe Bleffings to the fulleft extent,
I remain with the moſt profound Ref-
pect, and perfect Submiffion,
Your Royal Highness's
Ilington,
Moft Devoted and Obedient Servant,
Ann Murry.
25th March, 1799.
[ v ]
PREFACE.
THE Author preſents the following
Dialogues on Aftronomy and Natural
Philoſophy to the Public, as the Sequel
to Mentoria; and flatters herſelf that
they will prove uſeful to thoſe who fa-
vour them with their attention. The
fubjects ſhe has chofen are of ſuch a ſub-
lime nature, and their fcientific proper-
ties fo diffufive and profound, it may be
needful to obferve, that ſhe has endea-
voured to ſelect only thoſe branches that
tended to promote the general defign of
her performance, which was principally
to inſpire young minds with due reve-
a 3
rence
vi.
PREFACE.
rence for the univerſal operations of Di-
vine Wiſdom, manifeft in the various
parts of the Creation. In a work of this
kind, it is impoffible to offer any thing
new, or that has not been more ably dif-
cuffed by perfons of fuperior abilities and
refined claffical learning; yet it may be
productive of great benefit to the rifing
generation, to place theſe axioms or felf-
evident truths in fuch a point of view,, as
to imprefs the Juvenile Reader with a
juft conception of the regular order of
the Univerſe, and the collateral depend-
ence of every atom of which it is com-
pofed. The prevalent relaxation in the
ſyſtem of moral rectitude, claims the
moſt energetic exertions to counteract
its pernicious confequences; and no re-
medies can be fo efficacious as thofe that,
by early permanent impreffions, invigo-
rate the principles on the immutable ba-
fis of holy confidence, derived from the
emanations of the Supreme Being, which
Philofophy unfolds, and renders con-
formable
PREFA C E.
vii
formable to our finite powers. It may
perhaps be deemed preſumptuous in the
Author, to attempt a work replete with
ſuch abſtruſe and varied ſubjects for in-
veftigation; fhe therefore as the means of
extenuation, begs leave to plead, that ſhe
hopes and truſts her zeal will be accept-
ed, as a fubſtitute for the defects which
ſhe is conſcious the moft candid Critic
may difcover in the execution of her
plan. Aftronomy and Natural Philofo-
phy ſhould be confidered the native
fpring of dignified human ſcience, as
being the fource from which the moſt
fublime and general inſtructions are ob-
tained, it confequently cannot fail to be
effentially beneficial, to convey thofe fer-
tilizing ſtreams of information into a va-
riety of different channels, and to trace
their caufes and effects in every object
our ideas can compafs, from the fpan-
gled Etherial Firmament to the opaque
regions of the Earth, and the profound
abyſs of the Ocean. Theſe reſearches
unavoid
viii
PREFACE.
1
unavoidably produce conviction of the
Divine Efficient Power and Omnipre-
fence, which in youthful minds, un-
warped by prejudice, and unfullied by
immorality, infallibly operates as an an-
tidote againſt the inroads of Vice, and
in every age, ſtate, and condition, proves
a perpetual incitement to Virtue.
1
CONTENTS.
CONTENTS.
Ο
DIALOGUE I.
N Aftronomy, and the Sun, and Pla-
nets, with remarks on the Solar Syſ
tem, interfperfed with moral reflections
DIALOGUE II.
On the Secondary Planets, or Satellites, and
Comets, with a particular deſcription of
the Moon, and an account of the firſt
difcovery of Teleſcopes
DIALOGUE IH.
On the Fixed Stars, and the Zodiac, and
the progreffive improvements in Aſtro-
nomy, from the earlieſt ages to the pre-
fent period, with a conciſe deſcription of
the various fyftems that have been form-
ed and adopted
Page
1
30
50
DIALOGUE
CONTENTS.
DIALOGUE IV.
Page
On the Succeffion of Day and Night, and
the Viciffitudes of the Seafons, as pro-
duced by the Diurnal and Annual revo-
lution of the Earth, with appropriate ob-
ſervations, and moral reflections
1
DIALOGUE V.
On Eclipfes and Tides, with an explana-
tion of the general principle of Gravity
or Attraction, difcovered by Sir Ifaac
Newton, interfperfed with anecdotes and
reflections
82
109
DIALOGUE VI.
On Light and Darkneſs, their various pro-
perties philofophically and morally confi-
dered; to which is annexed, a definition
of the quality of Light, as relative to its
natural cauſes and confequences
DIALOGUE VII.
On Air, the Atmoſphere, and Sound, their
beneficial effects fpecified, and their gene-
ral qualities defined
136
153
DIALOGUE
CONTENTS.
xi
DIALOGUE VIII.
On
'n Electricity and Magnetifm, their pro-
perties concifely explained, and the gra-
dation of the reſpective improvements in
thoſe branches of Science enumerated,
with an account of the diſcovery of the
Magnet or Loadftone, and the Mariner's
Compafs
Page
169
DIALOGUE IX,
On Meteors of the Watery kind, their na-
tural caufes explained, and their philofo-
phical properties defcribed, illuftrated with
moral reflections on the nature and bene-
ficial confequences of Water
DIALOGUE X.
On Meteors of the Fiery kind, their natural
caufes deſcribed, and their varied effects
morally defined, with an explanation of
the philofophical properties of Fire
DIALOGUE XI.
193
226
On the Phænomena Halo, Parhelion, and
Rainbow, their cauſes and effects enume-
rated, interſperſed with moral reflections 242
DIALOGUE
xii
CONTENTS.
DIALOGUE XII.
On the Terraqueous Globe, various kinds
of Earth, Foffils, and Precious Stones,
their various properties explained, and
the effects of Divine Wiſdom manifeſt in
the Creation, morally delineated
DIALOGUE XIII.
On the Terraqueous Globe, Ores, Metals,
Vegetation, and Terreſtrial Beings, their
refpective characteriſtic qualities minutely
confidered, with immediate reference to
the univerſal influence of the Divine At-
tributes
Page
259
277
DIALOGUE XIV.
On Mountains, Rivers, the Sea, Submarine.
Productions, Fiſhes, Amphibious Ani-
mals, and Zoophytes, their various pro-
perties enumerated, and their effects mo-
rally inveſtigated, with reflections on the
operations of the Divine Providence,
Power, and Wiſdom, which are diſplayed
in the general œconomy of the Univerſe 297
DIALOGUE
DIALOGUE I.
MOND A Y.
On Aftronomy, and the Sun, and
Planets.
I
Mentoria.
have no doubt, my dear Lady Mary, you
recollect that in our converfation on the
Sciences, I engaged on fome future occafion
to expatiate more fully on the fubject of Altro-
nomy, on which I wish to fix your attention,
and will uſe my beſt endeavours to explain the
Elements of that fublime ftudy.
Lady Mary. I am rejoiced, Mentoria, you
have ſo ſpeedily fulfilled your kind intention,
B
and
2
On Aftronomy, Sc.
and I fhall hope to derive much entertainment,
as well as improvement, from your inftructions,
on a branch of education, of which I have fo
flight a knowledge.
Ment. You have an idea (though perhaps
an imperfect one) of what are uſually called
the Heavenly Bodies, or luminaries, which ap-
pear in the Celeftial Hemifpheres; I fhall
therefore proceed briefly to defcribe the Solar
Syftem, which comprehends the Sun, all the
Planets, their Satellites, and alfo the Comets.
The Sun, which is the center of this ſyſtem,
continues ftationary, that is, always in the
fame place; but revolves upon his own Axis,
in the fpace of about twenty-five days and an
half. The Planets, which are ſeven in num-
ber, conflantly move round him in their refpec-
tive fpheres. The names of thefe Planets,
which are ranked according to their feveral dif
tances from the Sun, are, Mercury, Venus,
the Earth, Mars, Jupiter, Saturn, and the
Georgium Sidus. Mercury, and Venus, are
called Inferior Planets, in confequence of their
moving within the Earth's orbit, by which is
to be underſtood, the being nearer to the Sun.
Mars, Jupiter, and the Georgium Sidus, are
styled fuperior Planets, becauſe their orbits or
paths
On Aftronomy, Sc.
3
paths are without that of the Earth, which
confequently removes them further from the
Sun.
The term Planet is derived from the
Latin word Planeta, roving, or wandering,
which denotes their quality.
Lady Louifa. I wait with eager expectation
to hear your deſcription of the Sun.
200
H
Ment The Sun, which is the fource of
light and heat, has been ever, imagined to be
a Globe or ſpherical body of fire.-Doctor
Herſchel, in fome late obfervations, appears
to be of a different opinion, and afferts, that
the Sun is an opaque body, and has hills, and
vallies; but as this is a new theory, it may
be best to regard it only as fuch, till the point
is proved beyond the poffibility of a doubt.
The diameter of the Sun is computed to be
893,522 Engliſh miles, his diftance from the
Earth, 95 millions of miles, and his proportion
of magnitude compared with the Planet we
inhabit, more than a million times as large.
Lady M. I am aſtoniſhed at your account
of the Sun's dimenfions: it does not appear of
fo great a fize as you deſcribe.
Ment. Which is to be afcribed to the im-
menſe diſtance the Sun is from the Earth:
it is from this caufe, that the Moon does not
appear fmall proportioned to her real fize,
B 2
when
}
4
On Aftronomy, &c.
when compared with the Sun, as fhe is fa
much nearer to us, every diſtant object ſeeming
as a natural confequence lefs, the farther it is
removed from our view.
Lady L. How wonderful it is, that theſe
bodies fhould appear fo bright and perform
their courſes with fuch regularity.
Ment. You will ceafe to be furpriſed at
thefe fects when you confider, that they are
under the guidance of Supreme Power and
Wifdem; and the further you proceed in your
reſearches, the more you will be convinced,
with the Royal Pfalmift, that "The Heavens
"declare the glory of God, and the Firmament
"fheweth his handy-work."
Lady L. I can clearly difcern the brilliancy
of the Planets; but have no idea of their form,
or ſubſtance.
Ment Their figure is that of a ſphere,
or globe, and their motion confifts of revolving,
or turning round upon their own Axis, from
Weft to Eaft; they alfo purfue a regular pro-
greffive motion from Weſt to Eaſt, through
their orbits, and thereby complete their revolving
courſe round the Sun, which is invariably fta-
tioned in the center of their fyftem. Their
brilliancy they derive from the Sun, as they are
in
On Aftronomy, &c.
5
in themſelves dark, or opaque bodies, and by
reflection tranfinit to us the light of that glo-
rious luminary. Dr. Herfchel is of opinion,
they may be poffeffed of fome inherent light;
but this is conjectural, therefore not to be reli-
ed on.
Lady M. I cannot comprehend what Orbits.
mean; pray Mentoria be kind enough to ex-
plain their fignification.
Ment. Every fubftance that is round, or
ſpherical, may be termed an Orb, and the ſpace
in which that body is deftined to more or act,
is in effect the Orbit. Thus to render the ap-
plication familiar to your perception, your eye
from its round form, may be conſidered as an
Orb, and the focket which contains it, con-
fequently its Orbit; but in a more enlarged
fenfe, it implies the path or courfe in which
any globular body moves, which often figura-
tively is termed the fphere of action.
Lady L. I now clearly underſtand the term
Orbit, and beg I may not protract your enter-
taining inſtructions reſpecting the Planets; but
hope that you will favor us with fome further
particulars refpecting the Sun; as that is a
fubject that intereſts me, in more than a com-
mon degree.
B 3
Ment.
€
On Aftronomy, &t.
Ment, I have already mentioned that the
Sun revolves on its own Axis in about twenty-
five days, it may be proper to obſerve, that the
Sun has alſo another motion, which is periodi-
cal, and is an elliptical, or nearly circular direc-
tion round the common center of all the pla
netary revolutions; and as this center nearly ap-
proaches to the Sun, he may with propriety
be regarded as the center of the planetary fyftem.
Lady L. How can it be poffibly known,
that the Sun revolves on its own Axis?
Ment. By obfervations refpecting the Ma-
culæ or ſpots, which evidently appear upon
his furface.
Lady M. I remember your mentioning the
ſpots on the Sun in fome of your former in-
ftructions: I wonder who firſt diſcovered them.
Ment. Galileo the famous Italian Aftrono-
mer, who perceived them about the year 1610.
Various opinions have been formed refpecting
their caufe, and quality; the moſt probable
conjecture is, that they are occafioned by an
eruption of fmoke, or other matter, of an
opaque nature from the Sun's furface, whilft
many ſuppoſe they are volcanoes in the Sun;
but theſe are ſubjects too occult and profound
for human inveftigation. In contemplating
the
On Aftronomy, &c.
7
the fplendor, beauty, and univerſal influence
of this glorious luminary, as connected with the
folar fyftem, we may with Thomſon declare,
He is the" beſt Image here below of his Cre-
ator." His beams produce Light, Heat, and
every other enlivening property to cheer, invigo-
rate, and perfect the general purpoſes of exift-
ence, in the animal and vegetable world: and
to him apparently, we are indebted, (as the in-
ftrument of his Divine Creator's power) for
every terreſtrial bleſſing that we enjoy : therefore
he is not only an object tranfcendently entitled
to admiration, but alſo a ſubject worthy of
ferious attention; as in the fublime language
of Milton, we may alfo obferve, that he is
of this great World, both Eye, and Soul;
yet must acknowledge God, his greater."
(6
Lady L. I feel very forcibly the juſt ob-
feryations you have made on the Sun; and
hope that you will now give me a defcription
of the Planets.
Ment. Mercury, which is nearer to the
Sun than any other of the Planets, completes
his courfe round him in the ſpace of about
88 days, or nearly three months, which con-
ftitutes his year.
Lady M. Excufe my interrupting you, my
B 4
dear
no
On Aftronomy, &c.
dear Mentoria; but how is it poffible that three
months fhould be a year
r?
Ment The word year may be regarded as
an indefinite term, as the space of time each
Planet takes to complete its courſe round the
Sun, is confidered its complete year. The
proximity of Mercury to the Sun renders his
heat intenſe, the degrees of which have been
computed to be feven times greater than what
is experienced in the Torrid Zone, therefore
there is every reaſon to conclude, that the tem-
perature of this Planet, muft differ very effen-
tially from that of the Earth, or it could not
in the natural courfe of things long remain in
that ſtate, as it has been computed, that the
degree of heat Mercury derives from the Sun
is 7 times what the Earth receives, which is
reckoned fufficient to make water boil. Mer-
cury is but rarely perceived, as he is uſually
hid in the fplendor of the Sun's rays, which
prevents the period of his rotation on his
own Axis being known. This Planet changes
his Phafes, by which is to be understood, ap-
pearances and pofitions, in nearly the fame
manner as the Moon, according to his fitua-
tion with reſpect to the Earth and Sun. He
never appears quite full, which is occafioned by
his
On Aftronomy Si,
19
his bright fide being only turned directly to-
ward us, when he is fo nearly approached, to
the Sun, as to be obſcured by his beams. By
theſe different Phafes it is evident he i not
endued with native light, which if he poffeffed
would cauſe him always to preferve a circular
or round appearance..
Lady M. How large is Mercury?
Ment. His diameter is 3261 Engliſh Miles,
and his mean diflance from the Sun 36 Millions
of Miles; his motion is fo rapid in his revolu-
tion round the Sun, it is computed at the rate
of 95000 Miles in an hour.
Lady L. In theſe wonderful inftances of
Divine perfection, it is not poffible to expreſs
the aſtoniſhment they produce.
•
Ment.. Mercury, which is the ſmalleſt of
the inferior Planets, as I have before mentioned,
can be but rarely feen, as the refplendency of
the Sun's beams generally renders him inviſible;
when he is perceptible he has a bright appear-
ance, blended with a light tincture of blue,
as the Orbit of this Planet is between the
Earth's Orbit and that of the Sun; if it were
in the fame plane as the Orbit of the Earth,
Mercury would frequently be ſeen to croſs the
face, or difk of the Sun; but as the planes of
B5
their
10
On Afronomy, &c.
their Orbits are not perfectly coincident, this
but feldom happens; when it occurs, it is cal-
led a tranfit of Mercury over the Sun's difk,
the Planet then appearing like a black ſpot on
the face of the Sun: the next that will probably
be viſible, will be on the 7th of May 1799, an
event that you will most likely have the plea-
fure of viewing if the weather is propitious.
Lady M. I fhall have great fatisfaction in
obferving the tranfit, and we are much obliged
to you for affording us this information.
Ment. Venus is the next fubject of our at-
tention, and the fecond Planet from the Sun:
her diameter is 7699 Engliſh miles. Her
revolution round the Sun is performed in 224
days, and her mean diſtance from the Sun is 68
millions of miles; her diurnal rotation on her
own Axis, is nearly 23 hours and a half.
This Planet when he appears to the Weft of
the Sun, rifes before him in the morning, and
is confequently denominated the Morning Star;
but when the appears to the Eaft of the Sun,
the ſhines after he fets, and from thence is cal-
Jed the Evening Star; in each of theſe ſituations,
The remains alternately, for nearly 7 months.
and a half. There is great reafon to fuppofe
this Planet has an atmofphere, as certain dark
moveable
On Aftronomy, Sc.
II
•
moveable ſpots have been diſcovered on her
difk, and aftronomers have perceived mountains
on her furface. When viewed through a tele-
fcope fhe is but ſeldom ſeen to ſhine with full
face, her phafes varying like thofe of the
Moon, and her enlightened part is invariably
toward the Sun.
Lady M.
Can Venus be perceived, without
the aid of a Teleſcope?
Ment. She can be clearly feen by the naked
eye, on account of her peculiar brightneſs, which
exceeds that of every other Planet; her luftre
has a whitiſh appearance, and is ſo brilliant ſhe
is frequently viſible in the day time even when
the Sun fhines, and ſhe has often been mistaken
for a Comet, when the is about 40 degrees re-
moved from the Sun. This Planet as a morn-
ing Star, is ſtyled by the Poets, Phoſphorus.
or Lucifer; and when the fhines after the Sun.
fets, and is hence called the Evening Star, the
is denominated Hefperus, or Vefper. The
ancients expreffed an extraordinary degree of
reverence for this Planet, on account of her
beauty.
Lady M. With what delight I ſhall now
view the ſtarry firmament, which before I
received your inftructions on Aftronomy, I did
B6
not
12
On Aftronomy, &c.
not regard with the attention and admiration it
deferved.
Ment. You have hitherto contemplated theſe
glorious Orbs, as mere oftenfible objects, with-
out being able to reflect on their importance,
magnitude, or diflance; and it is by the aid of
Science alone, and the labours of perfons of pro-
found learning, that you can poffibly acquire a
competent knowledge of fuch important truths.
The next Planet to Venus is the Earth, whoſe an-
nual revolution round the Sun is performed in
365 days, five hours and 49 minutes, being rather
more than twelve months; her diurnal rotation
on her own Axis is completed in about 24 hours,
her mean diſtance from the Sun is computed to
be 95,000,000 Engliſh miles, and her Diameter
7920 Miles.
Lady L. Pray Mentoria what is the cauſe
that fometimes there are 29 days in the month
of February?
Ment. In order to recover the time that the
Earth ſpends in her annual revolution round
the Sun, which by the foregoing ſtatement, you
will clearly perceive is more than 365 days, it
becomes neceffary every fourth year to add one
day to the month of February, this is called
Biflextile
On Aftronomy, &c.
13
Biffextile or Leap year, which confifts of 366
days.
Lady L.. It appears almoſt incredible that
the Earth fhould be in conftant motion, which
muſt be the caſe, from the account you give.
of her rapid progrefs round the Sun, and her
rotation on her own axis.
Ment. In a variety of inſtances we are re-
quired to ſtretch our belief, when the fubjects.
are above our comprehenfion; but in the pre-
fent cafe, the fact is demonſtrated beyond the
poffibility of a doubt, which is clearly proved,
by the viciffitudes of the feafons, the fucceffion
of day and night, and a variety of other felf-
evident means. To convince you of the rapi-
dity of its motion, I fhall inform you that the
motion of the Earth in its Orbit, is computed
at the rate of 68 thouſand miles in an hour.
Lady M. I am furprized this rapid motion
is not perceptible; I had no idea how faft I
was travelling, even when I am aſleep.
Ment. Extraordinary as it may appear, it
is a certain fact, that the Earth in its revolu-
tion on its own axis, moves with a degree of ve-
locity almoft incredible to our finite conception;
as from the moſt accurate calculations it ap-
pears,
14
On Aftronomy, &c.
pears, that the inhabitants of London are con-
veyed by this diurnal rotation 560 miles in the
ſhort ſpace of an hour; and at the Equator, it
is computed its progrefs and hourly motion is
at the rate of 900 miles.
Lady L.
What is the cauſe of our not per-
ceiving the motion of the Earth?
Ment. The regularity of its progreſs pre-
vents your feeling the fenfible effect of its re-
volutions; if the ſlighteſt obſtacle occurred, and
the motion confequently became irregular, the
whole Globe would perceive its force; but as-
the Earth is guided in its refpective revolu-
tions, by the fuſtaining hand of an all-wife
and gracious Providence, we must ceaſe to.
wonder at the uniformity, with which it per-
forms its deſtined courſes.
Lady M. I know that the Earth is a ſphere,.
but I wish to be informed of the nature of its
furface; as I think the rocks and mountains-
muſt rather alter its globular form.
Ment. The form of the Earth is not per-
fectly round, but rather flattened at the poles,
which is what is called a fpheroid; the rocks,.
and mountains, which are the greateſt height
form but inconfiderable protuberances on fo
large
On Aftronomy, &c.
151
large a body, therefore do not affect the bulk ini
any material degree. When we reflect on the
various properties of this habitable Globe, and
trace its qualities as a Planet, we are led in
the first place to conſider the bleſſings we enjoy,
and in the next, to look forward to thoſe which
are in ſtore for us in the endleſs ages of eter-
nity, when the preſent ſtate of things will
be annihilated, and like the bafelefs fabric of a
viſion, leave not a wreck behind!
Lady L. I wish to be informed by what
means you are convinced of the Rotundity of the
Earth.
Ment. The Earth being nearly of a fpheri-
cal form, as I have before fpecified, is con-
firmed by the following clear demonſtrations.
The firſt inſtance I fhall produce, is the cir-
cumſtance of its having been failed round, which
has been often effected by Navigators fteering
either in an Eaſtern or Weſtern direction, and
by purſuing the ſame courſe, returning to the
Port from whence they began their voyage.
The next proof is, that we may clearly perceive
when we are on the fea-fhore, and obſerve a
Thip failing from us, the firſt part we loſe fight
of is the hull of the veffel, then the lower
parts
16
On Aftronomy, &c..
parts of the mafts and rigging, till by degrees
the mafts difappear, and the whole object va-
niſhes entirely from our view. When a fhip
approaches near a port, the contrary effect must
be produced, the Mariners first perceive ſteeples
of Churches, and other ftructures of confidera-
ble height, and in regular gradation, houfes and
inferior buildings, and at laſt the ſurface of the
Earth becomes obvious to their fight. The ir-
regularity of the Earth occafioned by the in-
equality of its furface, is no argument in dif-
favour of its fpheroid form, as the projections
on its furface occafioned by the contraft of the
higheſt hills, or the loweſt vallies, it has been
computed, bear no greater degree of proportion,
than the inconfiderable protuberances that are
found on the rind of an orange, which by no
means deſtroy the fymmetry of its form. That
we have no fenfible proof of theſe extraordinary
truths conveyed to us through the medium of
our intellectual perceptions, does not prove a
contradiction of their exiſtence; our powers of
conception are great, but they are finite, and
in a variety of other fubjects, we are liable to
evident deception, occafioned by the limited im-
preffions our viſual organs receive: therefore we
บ
muſt
On Aftronomy, &c,
IT
must be thankful as frail beings, that we know
enough to be fenfible of the Omnipotence of
God, and of our entire dependence on his Pro-
vidence.
Lady L. Pray, Mentoria, receive my moſt
grateful thanks for your reflections on the blef-
fings we enjoy; and be affured, I will exprefs
my fenfe of them, by the most zealous efforts
of gratitude and praiſe.
Ment. The next Planet above the Earth's
Orbit is Mars, whofe revolution round the Sun
is performed in one year and 322 days; his Di-
ameter is 5312 English miles, and his inean di-
ſtance from the Sun 145 million of miles, and
his rotation on his axis is in 24 hours and nearly
half, which conftitutes the length of his day.
Mars when feen through a teleſcope, is obferv-
ed like the Moon to encreaſe and decreaſe, but
never appears horned; it is therefore natural to
conclude, he does not fhine by his own proper
light, and that his orbit includes that of the
Earth. This Planet when viewed by the eye
unaffiſted by glaſſes, appears ſmaller than Venus
and of a redder hue.
Lady M. I am furpriſed at fuch a diſtance
the
!
38
On Aftronomy, &c.
the length of time, can be determined fo exactly,
as by hours and minutes.
"
Ment. Thefe nice calculations are effected
by mathematical demonftrations, which reduce
fuch profound fubjects to the level of our com-
prehenfions, and by clear fimple means, con-
vince the moſt moderate underſtandings.
肴
​The next ſubject which demands our atten-
tion is Jupiter, which is the largest of all the
Planets, and in refpect to his diftance from
the Sun, is the next in rank to Mars; his an-
nual revolution round the Sun is performed in.
the ſpace of 11 years, 314 days, his Diameter
is 90,255 Engliſh miles; his mean diſtance from
the Sun is 494 millions of miles, and his rota-
tion on his own axis is completed in the fhort.
Space of 9 hours and 56 minutes, by which
means the velocity of his motion is fo great,
that at his equatorial parts, it is computed to be-
25 times greater than that of the Earth, and its
rapidity is afcertained at the rate of nearly 26
thouſand miles an hour. The portion of light
and heat that Jupiter derives from the Sun
are proportioned to thoſe received on the Earth,
as 37 to 1000; therefore it is peculiarly fortu-
nate for the inhabitants of this Planet, (and it
is highly probable there are fuch) that he is at-
tended
On Aftronomy, &c.
10
3
tended by four fatellites, or they would be but
in a very cheerlefs dreary ftate. The quick
fucceffion of day and night is another remark-
able inſtance of divine wifdom; as by that
means the ſpeedy return of day counterbalances
the other diſadvantages of fituation. In con-
fequence of the Axis of Jupiter being fo near-
ly perpendicular to his Orbit, he perceives no
variations of ſeaſons, and this was mercifully
ordained, becauſe if the Axis of this Planet
had inclined any confiderable number of degrees,
the fame proportion round each pole would
have been involved for nearly fix years in im
penetrable darkneſs. When viewed through
a teleſcope, Jupiter is found to be furrounded
by faint ſubſtances, denominated zones, or belts,
which are ſubject to fuch variations in their
appearances, they have been frequently afcribed
to clouds. When obferved by the naked eye,
Jupiter is diftinguiſhed for the white quality of
his brightneſs, and in brilliancy exceeds moft
of the other Planets excepting Venus, which
fometimes is fuperior in luftre. This is the more
extraordinary, when we reflect on his im-
menſe diſtance from the Sun, and muſt be in a
great meaſure afcribed to his vaft magnitude;
like
20
On Aftronomy, Sc.
like Venus, he is fometimes called a morning,
and at other times an evening Star.
Lady M. You frequently mention Diame
ters, are they in any degree like circumferen-
ces?
Ment. As the means of defining a ſphere,
or Globe, we must confider it as a round folid
body, the furface of which is equidiftant
from a certain point called its center, therefore
a line drawn from one fide to the other, through
the center, is called its Diameter, whilst the
circumference would imply the going entirely
round that or any other object: it may not be
unuſeful here to add, that the term magnitude
means fize, or bignefs; altitude the height of
any perfon, or thing; and plenitude fullneſs, all
of which point out the dimenfions and quality
of the relpective fubjects, to which they are
applied.
Lady L. Whenever I heard the Planets
mentioned, I thought that they were inconfi-
derable in fize, and by no means of the con-
fequence you reprefent; indeed I never paid
much attention, when they were the fubject of
difcourfe.
ent. This indifference to things fecming
ly too deep and abitrufe for our comprehenfion,
is
1
21
On Aftronomy, &c.
{
is one of the principal fources of the ignorance
which fo frequently prevails, even amongſt
thoſe who ought to be better informed. On
this fubject I ſhall only remark, that on all
topics, relative to the economy of Nature,
and the general ftate of things, you ſhould ever
employ your eyes, and ears, as inftruments to
convey inftruction; as there is ſcarcely any
branch of knowledge that is wholly unintelligi-
ble, or that may not in fome degree prove a
valuable attainment.
}
Lady. L. I will never neglect any means
of receiving improvement; but one does not
frequently meet with perfons qualified to in-
fruct.
Ment. In that idea you are greatly mistaken,
knowledge does not wholly confift in Scholaftic
learning; but in a great meaſure is produced by
obfervation and practice.
Illiterate perfons,
and thoſe in the lower claffes of life, may afford
much useful information, which they have ac-
quired by the regular diſcharge of their duty, or
the profecution of their refpective avocations.
Thus a Gardener may improve you in Botany,
a Carpenter in Architecture, or a Sailor in the
principles of Navigation and Geography, though
perhaps they exprefs themselves in incorrect
lan.
22
On Aftronomy, Sc.
language, and ambiguous uncouth terms, yet
you may fafely rely on their affertions, as they
are fpontaneouſly the effect of labour and expe-
rience, which are the baſis of the moſt effential
acquifitions.
Lady M. I will in future liften attentively
to every obſervation I hear; as I am convinced
of the advantages I fhall derive by that means.
Ment. The most valuable acquirements are
obtained by general, rather than by particular
modes of inſtruction; as the moſt uſeful infor-
mation uſually ariſes from exifting circumftan-
ces, which no formal precepts or elaborate lec-
ture could ſo well effect. Never neglect any
means that can enlarge your ſtock of know-
ledge, from the weak pretext it can prove of
no uſe; as experience daily teaches us, that our
intellectual powers in the viciffitudes of human
life, are called into action by various unforeſeen
meaſures, which are to conſtitute our line of
duty. Seek this invaluable treaſure with ar-
dour, let not the moſt humble inftruments which
impart it be ſpurned with difdain; as this
would be literally refufing a jewel of ineftima-
ble value, becauſe the vehicle which conveyed
it was apparently of inferior worth.
Lady L. I will always endeavour to con-
fider
On Aftronomy, &c.
23
fider the intrinfic merit of every object within
my powers of comprehenfion.
Ment. To fpeak figuratively on this fub-
ject, it is not alone from the Cedar of Leba-
non, or the ſtately Oak we are to gain inftruc-
tion; as even the moſt humble fhrub is fraught
with leffons to imprefs our minds with a fenfe
of the Deity, though his attributes ſhine with
more refplendent majeſty in the various orbs
which adorn the Firmament. The ſubject that
now demands our attention is Saturn, which is
the next Planet to the orbit of Jupiter, whofe
annual revolution round the Sun is completed
in 29 years, 167 days; his Diameter is 80,012
Engliſh miles, and his mean diftance from the
Sun 906 millions of miles. His rotation on
his own Axis has not yet been afcertained.
As this Planet is about 9 times and half further
from the Sun than the Earth, which is com-
puted to be nearly 900 millions, confequently
the light and heat he derives from that lumi-
nary, about 90
times 'lefs.
Lady M. The number of miles thefe Pla-
nets travel in their reſpective revolutions, will
make me think the fhort journies we take of
no importance.
Ment. I am happy to hear it likely to pro-
duce
翌年
​On Aftronomy, &c.
duce that effect, as it is one of the principal
ends of Aſtronomy to enlarge the ideas, and by
a due contemplation of the Supreme Being, in
theſe bright trophies of his fkill, to form there-
by a juſt eſtimate of his divine attributes, and
alſo of our own limited powers. I fhall now
proceed to inform you, that Saturn has feven
Satellites or moons, but the moſt ſurpriſing
phænomenon is a kind of ring that encompaſſes
his body, which from the moſt minute and
attentive inveſtigation, has been afcertained to
be about twenty-one thouſand miles diftant
from this Planet, and to be nearly thirty thou-
fand miles in breadth.
Lady L. What can be the ufe of this Ring?
I have no doubt it anfwers fome important
end.
Ment. There is every caufe, philofophi-
cally and rationally to fuppofe, that the Planets
are inhabited; and no one can doubt, however
near or diſtant from the Sun they are refpec-
tively fituated, that the conftitution, temperature,
and other circumftances of the Beings appro
priate to each are ſo conſtructed, harmonized,
and governed, as to form a perfect ſyſtem, in
every reſpect according to complete the general.
laws of the univerfe. This Ring like every other
5
atom
On Aftronomy, &c.
25
atom of created matter, undoubtedly fulfils
fome wife intention and purpoſe, and moſt pro-
bably was formed to cheer, and in fome degree
fupply the defect of heat, which must follow
as a natural confequence, from Saturn's remote.
distance from the Sun.
Lady M. How furprising thefe circumſtances
are;
if it were left to my choice to determine,
I fhould be undecided whether I thould prefer
Mercury, or Saturn, as the Planet on which I
was to exiſt.
Ment. This like many other inftances is
gracioufly ordained by a fuperior Power: the
hand that formed us can beft allot our place
and ſtation. It is not the degree of light and
heat, darkneſs or cold, which is to be our por-
tion, that is to form our happineſs, or mifery;
our proper blifs depends on the faithful diſcharge
of the duties and parts affigned us, therefore
we muſt think the fpace we inhabit is the
moſt congenial to our nature, and in our ideas
afpire to no higher fphere, than the immortal
reward revelation infures, as the confequence of
uniform obedience.
Lady L. I am very forry your account of
the Planets is ſo nearly completed.
Ment. The next and laft which I have to
C
defcribe
26
On Aftronomy, c.
defcribe is the Georgium Sidus, diſcovered the
13th of March 1781, by Dr. Herfchel; previ-
ous to that event, Saturn was confidered as the
moſt remote Planet from the Sun. In confe-
quence of this valuable difcovery being made.
in the prefent reign, it has the appellation of
Georgium Sidus given to it in honour of our
moſt gracious fovereign; it is alfo frequently
called Herfche!, to perpetuate the ingenious.
philofopher's fame who difcovered it, and
therefore is aftronomically characterised by an
H. being the initial letter of his name, with a
crofs, fymbolically, to denote it was by Chrif
tians this Planet was first explored.
Łady M. I cannot exprefs how much I am
obliged to you for giving me fo clear an account
of the Georgium Sidus; what pleaſure it muit
afford Dr. Herfchel when he made this difco-
very.
Ment. The promulgation of any fcientific
phænomenon may be confidered as one of the
moft brilliant efforts of human fkill, as it gives
a degree of preeminence to thofe who are for-
tunate enough to difcover them, fuperior to
every other rank or ftation. The Georgium
Sidus or Georgian, as he is frequently termed,
performs his courfe round the Sun in 83 years,
121
On Aftronomy, &c.
27
121 days, his diameter is 34,217 English miles,
and his mean diſtance from the Sun is 1812
millions of miles. In confequence of his im-
menfe diſtance, the period of his rotation on
his own Axis has not been afcertained. When-
ever this is the cafe, we are to afcribe it to the
being fituated fo remote from us; as there is
every reafon to conclude, that all Planets do re-
volve on their own Axis; though, in fome in-
ftances, theſe rotations cannot be perceived by
the inhabitants of the Earth. This Planet has
two Satellites, or Moons.
Lady M. The great diftance Georgium Si-
dus is from the Sun, muft caufe it to be very
dreary; as I am now enough of an Aſtronomer
to calculate in fome degree by the number of
miles, of the refpective mean-diftance from the
centre of its fyftem.
Ment. The light and heat which this Planet
derives from the Sun, is about the 360th part
of what is received at the Earth; as his diſtance
from the Sun is computed to be about 19 times
that of the Globe we inhabit. As the means of
giving you a notion of the climate of the Geor-
gium Sidus, you muſt endeavour to divide, and
fubdivide the proportions of light and heat this
Planet receives, when compared with the Earth;
which
C 2
1
On Aftronomy, &c.
28
which will enable you to form a precife idea,
how fmall a portion of the genial rays of the
Sun is allotted to theſe newly diſcovered regions.
Yet, let us not hence haftily conclude that Pro-
vidence has not difpenfed his bleffings with hist
accuſtomed liberality; but rather let us reft af-
fured, this, like every other Planet, and every
other part of the Creation, is constructed with
unerring fkill. The dimenfions of the Geor-
gium Sidus are 82 times as large when com-
pared with thofe of the Earth. Therefore,
when we confider the great magnitude, and the
ftupendous diſtance this Planet is from the Sun,
with what wonder and admiration muft we re-
flect on the power of that Supreme Being who
can fuftain this, and the other Planetary Orbs,
with fuch order and rapidity, through the re-
gions of the liquid air! The Planets already
fpecified, are called the primary Planets; be-
fides which, there are fourteen called fecondary
Planets, or Satellites, each of which revolves.
round the primary Planets that are the centre
of their motion, as the primary Planets re-
volve round the Sun. Thefe will be the ſub-
ject of my future confideration, I fhall there-
fore only fubjoin a few obfervations, and con-
clude this Lecture. As it is my wish to render
my
Sigs of the PLANETS.
Names
of the
PLANETS.
Diameters, in Engliſh
Miles.
Mean Dultance from the
Sun, in Mil. of Miles.
Periods, in
Years and
Days.
Sun..
Mercury
*893524
32610- 88
35
C+
Venus...
7699 0- 224 68
Earth
7920
I or 365 95
Moon...
2161
Mars...
I
531 and 322 145
24 Jupiter
Saturn....
9025511
800129-167 906
314 494
Georgian,
HI
or
3421783
121 1812
Georgium
The Diameters were taken out of Adams's
Lectures.
On Aftronomy, &c.
29
my inftructions as clear to your comprehenfion
as poffible, I have avoided all complex terms,
and have endeavoured to expreſs myſelf in lan-
guage fuited to your tender years. I do not in-
tend to ftrip Science of its dignity or grace,
but rather to adminifter to you fuch modified.
portions as your intellectual powers can eaſily
receive and digeft. To affift you effectually in
your purfuit of aftronomical knowledge, I will
furniſh you with a regular table of all the marks
or characters of the different Planets and prin-
cipal Stars, with their dimenfions, diſtances,
&c. which will enable you at one view, to col-
lect all the various inftructions on that point.
diffuſed through my converfations on this inter-
efting fubject. Let your attention be propor-
tioned to my zeal, and by their mutual com-
pact, your improvement will be eſtabliſhed on
a folid bafis.
C3
DIALOGUE II.
TUESDAY
On the Secondary Planets, or
Satellites, and Comets.
Mentoria.
I HAVE already informed you that there are
fourteen Satellites or Moons, which are
claffed as fecondary Planets; I fhall therefore
proceed to defcribe their refpective qualities,
and rotation through their different Orbits.
The Moon may be regarded as the first of thefe
Satellites, as the accompanies the Earth in its
annual courfe through its Orbit or path, and is
continually revolving round it in an elliptical ro-
tation from one new Moon to another, which
le performs in about 29 days, 12 hours, and
44 mi.
On the fecondary Planets, &c.
31
44 minutes; this is called her fynodical revo-
Iution, beſides which, he has another motion
that is termed her fiderial, or periodical rota-
tion, that is performed in 27 days, 7 hours
and 43 minutes; being the fpace of time fhe
takes to revolve from one point of the Hea-
The diameter of the
English miles: her
vens, to the fame again.
Moon is nearly 2161
mean diſtance from the Earth 240,000 miles,
and her motion in her Orbit is computed
to be at the rate of 2290 miles in an hour.
As this Planet's rotation on its Axis is perform-
ed in the fame ſpace of time as her revolution
through her Orbit, it evidently appears, that
her day and night together, are of the fame
length as our lunar months, as it is clearly de-
monſtrated, that the Moon turns but once on
her Axis during her progrefs round the Earth.
Lady Mary. I am rejoiced that you are in-
ftructing us on the fubject of the Moon, which
is an object that I admire more than I can ex-
prefs; and I feel impatient to be informed
why it changes and differs in appearance.
Ment. At the period of the new Moon, fhe
is in that part of her Orbit or path, which is
between the Earth and the Sun, therefore the
whole of her enlightened Hemifphere is turned
C 4
from
32
On the fecondary Planets, c.
from the Earth, and ſhe is faid to be in con-
junction with the Sun. I make no doubt
you recollect, that the Moon as well as the
primary Planets, is a dark or opaque body;
therefore, the light the difpenfes is received.
from the Sun, by which means, only that half
can be illuminated that is turned towards that
brilliant Luminary, and the other half muſt be
deprived of light; confequently, the degrees of
light we receive, and the different appearances
of the Moon, are occafioned by the various po-
fitions with refpect to the Sun and Earth, which
the face of the Moon at different feaſons pre-
fents to our view.
Lady Louifa. This I clearly comprehend;
but what is the next ftage of this beautiful Pla.
net?
Ment. When ſhe has performed one quar-
ter of her courfe through her Orbit, what we
perceive of her enlightened Hemifphere, is of
a femicircular form; which we denominate her
first quarter. When ſhe has performed half her
revolution through her Orbit, the whole of her
enlightened Hemifphere is turned towards the
Earth, in which poſition fhe is in oppoſition to
the Sun, and in that ftate conftitutes what is
called
On the fecondary Planets, c. ·33
+
called a full Moon. At this period, the Sun and
Moon are in oppofite parts of the Heavens:
the Moon riſing in the Eaſt, and ſetting in the
Weft. When the Moon has paffed three quar-
ters of her Orbit, fhe again refumes a femicir-
cular appearance, and is then faid to be in her
laſt quarter; and when her whole revolution is
compleated, her enlightened Hemifphere is not
viſible to us, and another new Moon regularly.
fucceeds. As the means of rendering this mat-
ter familiar to your perception, if you hold an
ivory ball before a candle in a variety of poſi-
tions, the effect will be clearly evinced by the
proportion of light that will be viſible on the ile
luminated part of its Hemiſphere. You muſt
alſo imagine, that if it were poffible for you to
view the Earth from the Moon, fhe would
exhibit the ſame phafes, or pofitions as the
inhabitants of the Earth perceive, only in di-
rect contrary means; the one being at full,
when the other changes, and in a greater pro-
portion, as the Earth yields 13 times as much
light as the Moon, in confequence of her ſu-
perior magnitude; her bulk being about a fif-
tieth part of the Earth; and as the axis of the
Moon is almoſt perpendicular to the plane of
the Ecliptic, fhe cannot experience any vicif-
fitude
C 5
3+ On the fecondary Planets, &c.
fitude of feafons. Many Authors have ima-
gined fhe has no atmoſphere, but later difco-
veries confirm the contrary opinion.
Lady L. Pray, my dear Mentoria, deſcribe
the various appearances the moon exhibits, as
its face often feems to change.
Ment. You have no doubt frequently obferv-
ed that the Moon appears of different ſhades and
colours. When this Planet is viewed through
a teleſcope, it is clearly demonftrated that
theſe varied tints are produced by the contraſt
of hills and vallies; the mountainous parts oc-
cafioning the light fpots. It was till lately uni-
verfally believed, that the dark ſpots or fhadows
were feas; but modern difcoveries have prov-
ed they are concavities or caverns.
Lady L. I am amazed that theſe things can
be diſcovered with fuch clear proofs.
Ment. The circumftance of there being
hills and vallies, which produce the effect al-
ready defcribed on the furface of the moon, is
alfo demonftrated by the border or outer regions
of the edge appearing indented about the ex-
tremity of the illuminated part, when the
Moon is either horned or gibbous. Dr. Her-
fchel has afcertained the height of ſeveral of
thefe hills or mountains; and has proved that
77
very
J
On the fecondary Planets, &c. 35
very few of them, in their perpendicular eleva-
tion exceed half a mile; in the courfe of his
obfervations on this Planet, he has alſo explor-
ed feveral volcanoes, which emit fire, and from
the great fimilarity there appears between her
and the Earth, it is a probable conjecture, that
ſhe has not only feas and rivers, but alſo an
atmoſphere.
یر شد
Lady L. You have frequently defired I would
request the explanation of any word above my
comprehenfion, therefore I beg to be informed
what gibbous means?
J
- Ment. It is an aftronomical term often ufed
in reference to the enlightened parts of the
Moon, while fhe is moving from the full to the
first quarter, and from the last quarter to the
full again; as at thofe periods the dark part ap-
pears horned and falcated, and the light one
protuberant, convex, or gibbous; as the means
of fully explaining this matter, I will inform
you that the word falcated, implies crooked,
and is applied to exprefs when the moon or any
other planet appears crooked or in the form of
a fickle.
A
?
Lady M. Pray, my dear Mentoria, explain
to me why the Moon rifes at different times.
Ment. The enlightened part from the new
C 6
to
36
On the fecondary Planets, &c.
to the full Moon is turned towards the weſt,
as the Sun is weſtward of it; but on the
contrary from the full to the new Moon, it is
turned to the eaſt, as the Sun at that period is
eastward of it.
Lady L. Does not the Moon fometimes ap-
pear larger than at others?
Ment. The full Moon which happens di-
rectly before the Autumnal Equinox, in her
dimensions appears larger at the time of her
rifing than ufual, and for feveral fucceffive
evenings rifes nearly at the fame period, im-
mediately after the full; this is by many called
the Harveſt Moon.
Lady M. Have I not heard alfo of a Hun-
ter's Moon?
Ment. It fometimes happens that the fame
circumſtances occur, as I have juſt deſcribed
in the fucceeding Moon, though. not in fo
great a degree; this is what is often denomi-
nated the Hunter's Moon. Theſe extraordi-
mary variations proceed from the Moon's pe-
culiar fituation with refpect to the Earth at
thoſe periods, which would be too abftrufe for
me to endeavour to explain in terms fuited to
your comprehenſion.
>
Lady L. I have been particularly attentive
to
On the fecondary Planets, &c
37
to your remarks on the Moon, which I fhall
now admire more than ever, I always imagin-
ed it had no other uſe than to afford us light.
Ment. The great Creator of the univerſe
wifely ordains, that his works fhould coincide
to proclaim his divine attributes, and alſo ſerve
the fubordinate purpoſe of beneficial effects to
the various beings he has formed. In contem-
plating the univerfe, or at leaſt thofe parts which
our finite ideas can compriſe into one ſyſtem,
we ſhall clearly perceive mutual advantages are
the grand outline of the general economy of
nature: thus Philofophy teaches us, as inhabi-
tants of a planetary orb, that our Earth tranſ-
mits light to the Moon in the fame manner as
we derive it from her. The proportion of light
the Moon affords to us, it has been computed is
ninety thouſand times lefs than day light, which
is infufficient to make any fenfible effect of
heat; but the light the Earth yields to the Moon
is calculated to be 13 times as much, which I
have before obſerved.
Lady L. I cannot poffibly exprefs, how
much I admire the ferenity of a Moon-light
night.
Ment. The calm delight that the lunar
fplendor affords, has furniſhed Poets with ma-,
terials
38
On the fecondary Planets, &c.
terials for the most beautiful defcriptions; every
object beheld through this meliorated medium,
acquires additional grace, and its benign ef-
fects may be traced by the influence they have
on the human mind. The light which the
Moon in its brighteſt ſtate reflects from the Sun,
is of that mild quality, to concéntre the ima-
gination, whilft more vivid rays would tend
to diſturb, and extend its range to objects, not
fo well fuited to the purpoſes of ferious con-
fideration, or devout contemplation. The
Moon is to the works of nature, what modefty,
or diffidence, is in its effects on the moral
.world; by the diffufion of their gentle beams,
the hemifphere of the Heavens, and of human
life, are ſeen through a veil, which invariably
adds a fuperlative degree of Grace to their
Beauty.
Lady M. I am extremely forry that you
have cloſed your account of the Moon; as it
is a very intereſting ſubject.
Ment. It is rendered peculiarly deferving of
attention, as being the, conftant attendant on
the Earth, which induced me to expatiate fo
fully on its qualities; but, I muſt now. pro-
ceed to confider the other Satellites, and inform
you that Jupiter has four Moons, thefe Orbs
are
On the fecondary Planets, &c. 39
are all of a ſpherical form, and derive their
light from the Sun: Saturn has feven Satellites
or Moons, and Georgium Sidus two; thefe
Orbs, or fecondary Planets, no doubt were
created for the gracious purpoſe of general be-
nefit to the primary Planets which are the cen-
ter of their motion, and unquestionably tend
to complete the regularity and order of the
folar fyftem. I have already mentioned the
luminous or bright ring, which encompaffes
Saturn at a very confiderable diſtance from his
body, in which fpace, the fixed ftars may
fometimes be clearly perceived. By a late dif
covery made by Dr. Herfchel, it is clearly
proved, that this ring is divided into an interior
and exterior circle, which are feparated from
each other by a ſpace of one thouſand miles.
Thefe Satellites, and Saturn's ring, can only
be ſeen by the aid of a teleſcope, by which
means alfo, feveral parallel faint ftripes may be
obſerved on the body of Jupiter, that are ufu-
ally denominated belts.
Lady L. What ingenious things teleſcopes
are, how clever thofe perfons must have been
who invented them.
Ment. This like many other valuable diſ-
coveries was effected apparently by chance.
The
40
On the fecondary Planets, &c.
The teleſcope is reported to have been invented"
by Roger Bacon in the 13th century; but from
the bigotry and ignorance of that æra, it
gained no repute, and was wholly neglected,.
till a fortunate circumftance convinced the
learned of its great utility, by the following
means. The children of a ſpectacle-maker
at Middleburg in Holland, whilft they were
playing in their father's fhop, made him ob-
ſerve, that when they held two ſpectacle glaffes
at fome diſtance from each other, they faw
the weathercock on the Church ſteeple appear.
much larger than uſual, and apparently very
near to them, but reverted. The father con-.
vinced of this effect, placed two glaffes upon
a board, fet upright, in two braſs circles, which
he could fix at what diſtance he pleaſed. In
confequence of this difcovery many reforted
to his fhop, among whom were Zachariah.
Janfon, and James Metias, workmen of the
fame town, who improved on the plan firſt
fuggefted, by adding a tube to connect the
glaffes, which by fliding in grooves, they could
extend to any length. Thus much for the me-
chaniſm; but for the fcientific advantages, we
are indebted to Galileo, Aſtronomer in the 16th
Century to the grand duke of Tufcany, who
only
On the fecondary Planets, &c.
41
only having heard this valuable diſcovery men-
tioned, had fo clear an idea of the importance
of this inftrument, he conftructed one on a ve-
ry large fcale, by placing glaffes in the long
pipes of an organ, by which means he firſt per-
ceived the Maculæ or fpots on the Sun, and its
revolution on its Axis; he next obferved the
four Moons of Jupiter, which he called the
Stars of Medicis, in honour of his patron.
He had alfo a glimpfe of two fides of Saturn,
which have been fince afcertained to be the ring
I have juſt deſcribed. As he was a man of
great learning, he publiſhed an account of theſe
acquifitions in the fcience of Aftronomy, and
gave a clearer idea of the heavenly bodies than
had ever been before attained.
•
Lady L. How much we are obliged to you,
my dear Mentoria, for informing us of the ex-
traordinary means by which the teleſcope was
difcovered. I am almoft induced to envy the
perfons fortunate enough to be the projectors
of ſuch an important invention.
Ment. I am inclined to think it ſhould ra-
ther excite your admiration; for if we were
minutely to trace all acquifitions of Science, or
knowledge; we ſhould be the more clearly con-
vinced theſe things are permitted by the wife
t
defigns
42
On the fecondary Planets, &c.
defigns of Providence; and that the perfons who
effect them are the mere agents, or inftruments
to fulfil his benign purpoſes for the general good;
as, what we call chance, is a fallacious tèrm,
and may almost univerfally be attributed to a
higher fource.
Lady M. I will in future endeavour to af-
cribe all good confequences and important
events to where it is moſt juſtly due, the Omni-
potent Ruler and Creator of the Univerſe; as
every object I contemplate proclaims its natural
dependance, and the divine protection it re-
ceives.
}
AA
Ment. Your ingenuous mind may be com-
pared to a maſs of fnow or wax, as it is as im-
maculate as the one, and as ductile as the other.
Impreffions must be received, and from the ſtate
of our nature, will be retained; therefore, their
quality becomes an object of the first im-
portance. The moſt ignorant and prophane
are fenfible that they exift, and enjoy many
bleffings; but it is only the enlightened and
devout Chriftian who can be convinced of the
means by which thefe advantages are obtained,
or be acceptably grateful to the fupreme Firft,
and general Caufe!
3
Lady L. Pray Mentoria, what will be the
next fubject on which you will expatiate ?
Ment.
On the fecondary Planets, 3e. 43
Ment. The only branches of the folar fyf
tem I have to explain are Comets: They are
folid bodies of various fizes which move round
the Sun, and cross the Orbits of the Planets in
a variety of directions. Their principal diſtin-
guiſhing marks from the Planets, are their long
tranſparent tails, which proceed from their fide
fartheft from the Sun, and have the reſemblance
of a pale flame. Their revolutions are exceed-
ingly eccentric, and the Orbits or paths in
which they move, Ellipfes, or long ovals of a
furpriſing magnitude, having the Sun in one of
their foci; in confequence of which, in one pe-
riod of their rotation, they are ſo near the Sun
as to be in a ſituation which muſt render them
fubject to the influence of the moſt intenſe heat,
as they fometimes approach much nearer than
Mercury to the folar Orbit, at other periods
they fly off again to fuch immenfe diftances
from the Sun, they muft experience the greateſt
degrees of cold. That which appeared in the
year 1680 came fo near to the Sun, its heat, it
has been computed, must be confequently 2000
times greater than red hot iron. After which it
purſued its courſe to the remote diſtance of near
cleven thouſand millions of miles, which is
calculated
!
44
On the fecondary Planets, &c.
calculated to exceed fix times the Orbit of
Georgium Sidus.
From theſe circumftances it is evident that
Comets are of a folid and durable fubftance,
capable of bearing the variations of extreme
heat and cold without being fubject to diffolu-
tion from their powerful effects; and are alfo
opaque bodies, as the light they fhine with is
received from the Sun, like the Planets I have:
before deſcribed.
Lady M. I think I have heard you ſpeak
of Comets, and call them blazing ſtars.
-
Ment. They are fometimes fo denominated
becauſe they have long tails of a blazing qua-
lity which proceed from them.
Lady L. Pray Mentoria give me fome idea.
of the dimenſions of a Comet, and the nature of
their tails, which you fo frequently mention.
Ment. Comets differ in magnitude, ſome of
them are larger than the Moon, though the
greater part are inferior in fize to that Planet ;.
but as they but rarely appear, and take an im-
menſe circuitous range, neither their periods
nor dimenſions are preciſely aſcertained..
Lady L. I cannot underſtand what-you
mean by the Comets having the Sun in one of
their
1
On the fecondary Planets, &c.
45
their Foci, in their periods through their ellip-
tical orbits.
Ment. The term Foci implies the two
points of convergency (by which you are to
underſtand the approaching nearer and nearer,
tending to one point) in the axis of a curve or
lens, therefore Foci is to be confidered as the
plural of Focus, which fignifies concentring
our views or attention to one point or object.
Lady M. Pray Mentoria explain what the
Comets' tails are formed of.
Ment. The tail of a Comet is fuppofed to
conlift of a great quantity of fume or vapour
which proceeds from its body, as it acquires
an accumulated degree of heat in its approach.
to the Sun. Some of thefe flaming appendages
are of a prodigious extent; having been com-
puted to be 80 millions of miles in length.
Though the tail is a diftinguishing character-
iftic of Comets, it is afferted fome have appeared
without them, and in every reſpect ſpherical in
form like the Planets.
Lady L. What can be the ufe of Comets?
Ment. Their importance I cannot define,
though I may venture to affert, they are of
confequence in fome degree or means too diffi-
cult for me to comprehend or explain. Vari-
Ous
46
On the fecondary Planets, &c.
ous conjectures in the early ages of the world
were formed from their appearance, as being
portentive of fome national evil or great event.
Many fuppofe the deluge was occafioned by the
near approach of a Comet to the Earth; whilſt
others, with greater probability, imagine they
will be the inftruments of effecting the general
Conflagration revelation teaches us to expect.
As if a Comet, in its return from the Sun,
fhould be in immediate contact with the Earth
in its Orbit; the latter mult be confumed in
the unequal conflict. It is generally imagined.
that there are at least 21 Comets belonging to
our fyftem; the periods of only three have been
accurately determined, which have been demon-
ſtrated to return at intervals of 75, 129, and 575
years. That which appeared in 1680 was the
moſt remarkable, as its greateſt diſtance from
the Sun is computed at 11 thoufand 200 mil-
lions of miles, whilft its leaft diftance from the
centre of the Sun is only 490 thouſand miles.
Its period is calculated 575 years, and in the part
of its Orbit which approaches neareſt to the
Sun, the velocity of its motion is computed to
be 880,000 miles in an hour, and the Sun, as
feen from it, appears 40,000 times as large as he
does to the inhabitants of the Earth.
Lady M.
On the fecondary Planets, &c.
47
Lady. M. From the accounts you give of
Comets, and their probable tremendous confe-
quences, I fhall be greatly alarmed when any
appear.
Ment. I ſhall endeavour to combat, and I
truſt ſhall overcome any apprehenſions you may
experience on that, or any other fubject relative
to the laws or order of the Univerſe. As in-
habitants of this terraqueous Globe, we are
obnoxious to two kinds of danger; the
one I fhall term individual, or partial; the
other, general, or univerfal evil; neither of
which we can avoid; as a variety of cir-
cumftances.concur to produce fuch baneful, or
fatal effects. Theſe confiderations naturally
fuggeft an entire and, unconditional reliance on
the decrees and difpenfations of Providence, and
fortify our minds againſt the dread of any par-
ficular misfortune, or trial: In the courfe
of human events it feldom happens, that the
afiction we apprehend occurs, or if it does,
the goodneſs of God enables us to fuftain the
conflict with due refignation to his divine will.
It would be as abfurd to dread the fatal confe-
quence of a Comet, as to entertain the idea,
that the Sun would fly from its Orbit, or the
Sea tranfgrefs its bounds. The laws of Nature
5
are
48
On the fecondary Planets, &c.
are in the entire difpofal of their omnipotent
Creator, nor will they deviate from their due
courfe but by his awful fiat; as they are not
guided by the fortuitous effects of chance, but
are reſtrained and directed by unerring wiſdom
in their reſpective revolutions and ſtations. It
would be impious and prefumptuous to judge of
the final effect of things: that terreftrial glo-
ry muft end, is an article of our religious faith,
and the baſis of our future hope, which points
to Eternity, and the expectation of a fuperior
and more permanent exiſtence. Refpecting the
nfeans to effect this great purpoſe, we are not
to form opinions from our finite ideas, but ra-
ther to conceive, the moſt awful meaſures may
be uſed as inftruments of executing the aveng-
ing decrees of an offended, yet merciful Deity.
On this fubject I fhall only add, many are of
opinion that the general conflagration which is
fcripturally denounced to deftroy the Earth, will
probably be produced by an eruption of the
volcanoes that are in various of its parts;
which theory they ſupport on the argument,
that every body poffeffes inherently the princi-
ples or feeds of its own diffolution. I have ex-
patiated more fully on this fubject, as I would
wiſh you to be forcibly impreffed with every fa-
cred
On the fecondary Planets, Sc.
49
cred and divine prefage, yet to be neither pain-
fully folicitous concerning the period, or the
means of their refpective fulfilments, nor weakly
indifferent concerning a tranfit that muſt con-
fign you to endleſs mifery, or fupreme blifs;
which latter, you will certainly attain if you
truſt in God, and regulate your conduct by the
precepts of the Chriftian Religion, and the
bright example of its Divine Author.
D
DIALOGUE
DIALOGUE III.
WEDNESDAY.
On Aftronomy, the fixed Stars,
and the Zodiac.
Mentoria.
N confequence of my having finished my
IN
account of the folar fyftem, I fhall now
endeavour to claim your attention whilſt I deſ-
cribe the fixed Stars, which are diftinguiſhed
from the Planets by their conftant twinkling,
or what is ſcientifically called their ſcintilla-
tion.
Lady. Louifa. Why are they called fixed
Stars?
Ment. Becauſe they never relatively change
their fituation, but always preferve the fame.
diſtance
On Aftronomy, &c.
السط
distance from each other, notwithſtanding the
Earth in its revolution, caufes an evident mo-
tion in the Heavens. It is imagined thefe Stars
are all diſtinct Suns placed at immenſe diſtances
in the Univerſe, each of which ſhines by its
native light, and forms the centre of a fyftem,
round which, Planets revolve with the fame re-
gularity as in our ſolar ſyſtem, but at too remote
a diſtance to be perceptible to us. As thefe
Planetary Orbs derive light only from their
reſpective Suns, that cannot be tranfmitted at fo
immenſe a diſtance; which is fo great, that
even Sirius, or what is ufually called the Dog
Star, never ſeems to vary in its fize, though in
one period of the Earth's revolution it is 195
millions of miles nearer to it than it is in the
oppoſite part of its Orbit. Thefe fixed Stars:
are ranked in fix different claffes to afcertain their
reſpective magnitude and diſtance, according to
the degree they are to us apparent. The num-
ber that can be perceived in the vifible Hemif-
phere without the aid of a teleſcope, fcarcely
exceeds one thoufand; but by the affiftance of
optic glaſſes, thoſe that may be ſeen are incalcu-
lable. And in proportion as theſe viſual auxi-
liaries improve, the celeftial regions are explored
with greater accuracy, and new diſcoveries con-
fequen ly
D' 2
52
On Aftronomy, &c.
"}
fequently made refpecting the number and qua-
lities of the heavenly bodies. By various af-
tronomical obfervations it has been proved, that
Sirius, which is nearer to the Earth than any of
the fixed Stars, is computed to be diftant more
than two millions of millions of miles. And
it is calculated that if a cannon ball were to fly
from thence at the amazing rate of 400 miles
in an hour, it would not reach the Planet we
inhabit in 570,000 Years.
Lady Mary. I am furpriſed that you def
cribe the xed Stars as Suns, I always thought
there was but ce luminary that bears that ap-
pellation, or was of equal confequence.
Ment. Qualities and properties, not terms,
are what we are to regard in fcientific difqui-
fitions; in this inftance I do not require impli-
cit belief till I have eſtabliſhed fufficient autho-
rity of the probability and rationality of my
affertions. A variety of opinions might per-
plex your ideas, and confuſe your judgment: I
ſhall therefore only produce Doctor Herſchel's
fentiments on this fubject. He thinks it will
fcarcely admit of a doubt, that the fixed Stars.
are diftinct Suns; or their immenfe distance
would perfectly exclude them from our view,
if the light they emitted were not of a ſolar
quality.
On Aftronomy, &c.
53
quality. He also carries this analogy ſtill far-
ther, by proving that many, (and moſt probably
all) of the fixed Stars turn on their Axis, and
have ſpots or maculæ on their ſurface which va-
ry in luftre and appearance. The Stars which
he particularly ſpecifies for theſe folar character-
iftic marks, are called Lyracephei, Antinoi, and
Ceti, with many others he does not particularly
From thefe obfervations it is evi-
enumerate.
dent our Sun and folar fyftein make but a ſmall
part of the Univerfe. As it is highly probable-
there are millions of Suns, attended by plane-
tary Orbs, inhabited by myfiads of rational be-
ings; all tending to the glory of their great
Creator, and uniting to fulfil the general pur-
pofes ordained by Divine Wiſdom.
Lady L. I am quite convinced by the proofs
you have given, that the Earth comparatively
makes but a ſmall part in the general maſs of
the Univerſe.
Ment. In afcertaining our real importance
in the Arcana of Nature, we muſt imagine an
expanfe of boundleſs fpace, and reflect that if
our folar fyftem were annihilated, it would bear
no greater degree of proportion of defection in
the whole Creation, than if a drop of water
D 3
were
54
On Aftronomy, &c.
were taken from the immenfe reſervoir of the
ocean.
Lady L. Have I not heard of the galaxy,
or milky way; pray what does it mean? I have
an idea it is an aftronomical term.
":
Ment. The galaxy, or milky way, derives
its name from the white appearance fuch an
immenfe number of ftars occafions, which unite
in illuminating that part of the heavens in
which they are fituated. Dr. Herſchel ima-
gines this broad circle is an extenfive ftratum
of ſtars, as he has difcovered many thouſands
in it, fome appearing double, others treble; not
that they are fo in reality, but are ftars at differ-
ent diſtances, which produce that effect by be-
ing feen in the direction of nearly a right line.
As the means of rendering my inftructions
more explicit, I fhall fubjoin a copper-plate,
which will clearly defcribe the three diftinct re-
gions of the Northern and Southern Celeſtial
Hemiſpheres, and the Zodiac. The ancients
expreſſed theſe fixed ſtars by certain imaginary
fymbolic figures of beafts, birds, filhes, and
other animals, which are called Conftellations.
The number of thefe ftars, including thoſe
which have been added in confequence of latter
diſcoveries in the Northern Hemiſphere, is 36,
in
340
350
360
330
*
*
Pisces
320
olle
0.00
NORTHERN CŒELESTIAL HEMISPHERE.
Antinous
obe
Aquaba
Equator
TVCe berus
Serpentarius
erpens
Equiculus
*
Pegasus
Delphinus
*
*
Vulpecula
Cygnus
Anser
Lyra
ས་སོ་་
Draco
er
Hercules
Corona Sep
Androm
North
Pale
Trangul Mag.
Medus
Caput
Ecliptic
Aries
Taurus
30
*
*
Arctic
*
ka Major
Tyna
*
*
votes
Charal
El.
Leo Minor
Gemint
Cancer
50
60
Drawn & Degravd by Rufell, Grape Los La Road
*
Crian
No
Monoceros
2010
Published by C. Dilly March 15,99 ·
Canig Jula
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280
270
SOUTHERN CŒELESTIAL HEMISPHERE.
2610
25
Equator
300
290
240
23.0
2210
*
*
fextans
Urania
Grater
150
Libra
140
130
Scorpio
Hydra
Centaurus
I.Rupell del et joulp.
120
Serpentartic
Soutum
Ecliptic
Sagita
*
Lupus
FLAD]
Argo
110
Corona
Australis
South
Pole
Pave
\ \\ | ///
Canis Major
Sirias
of Cancer
SunrooN
Colum
Grus
Aust
*
**
*
* Sn
Fidany
snda T
*
*
Pegel
Eridanu
*
100
Orion
90
Publish'd by CDilly March1; 1799 ·
70
320
340
Aquarius
**
*
20
*
*
*
330
10
4'0
360
390
340
Cetus
10
༩
OF
On Aftronomy, &c.
55
in the Southern 32, and in the Zodiac 12.
Some ſtars that are not comprehended in any
Conftellation, are termed unformed ftars; 0-.
thers Nebulæ, that have a cloudy appearance;
and thoſe that cannot be ſeen without optic
glaffes, are called Teleſcopic Stars. By the
invention of John Bayer, a German, about the
year 1600, the letters of the Greek alphabet are
ufed to exprefs the ftars in each Conftellation,
according to their regular gradation; though
fomé of the principal fixed ftars have diftin&t
names affigned them, of which you ſhall have a
lift.
Lady M. I fhall endeavour to acquire a
thorough knowledge of theſe appellations, and.
fhall purſue the method you fo often have re-
commended, of writing them in a little book,
which will prevent their eſcaping my memo-.
ry.
Ment. The Polar Star is the leaſt far in
the tail of Urfa Minor, or the Leffer Bear
on account of its proximity to the North Pole,
its apparent fituation with refpect to the earth
fcarcely varies through the complete period of
her annual revolution, which caufes this ftar to
ſerve as an unerring guide to mariners. There
are two ſtars in the Conftellation of Urfa Ma-
D 4
jor,
·56
On Aftronomy, &c.
jor, or the Greater Bear, which are called
Pointers, as they evidently point to the Polar
Star. Sirius, or the Dog Star, rifes and fets
with the fun during part of the months of July
and Auguft, which fpace of time conſtitutes
what are ufually called Dog Days.
Lady L. By what means can I diftinguish
the planets from the fixed ftars?
Ment. There are two invariable rules which
ferve to afcertain their diftinct qualities, every
fixed ftar twinkles; but a planet has not the
leaft degree of fcintillation, they are alfo always
-in motion from one part of the heavens to the
other, and are vifible earlieft in the evening,
and lateft in the morning: whilft the fixed
ftars conftantly preferve the fame diſtances from
each other.
Lady M. What occafions the twinkling of
the ftars, which you mention?
Ment. This effect is produced from the a-
gitated ſtate of the body of air or atmoſphere,
through the medium of which we view the
ftars; as the particles, by being in continual
motion, caufe a twinkling appearance in any
diftant luminous body and you must recollect
the fixed ftars fhine with inherent native light,
and
On Aftronomy, &i.
57
and that the planets are of an opaque, or dark
quality.
Lady L. You obferve that the number of
flars which can be feen without a teleſcope,
fcarcely exceed a thoufand, which furpriſes me
greatly; as when it is a fine night, they appear
to me innumerable.
Ment.
The cauſe of their appearing fo
much more numerous than they are in reality,
is occafioned by their conftant twinkling, and
the confuſed manner in which we view them
with our natural organs of fight.
Lady M. By what means do the Planets
appear like ſtars?
Ment.. This refemblance arifes from the
following circumftances. In whatever part of
the univerſe we are, our fituation feems to be
the centre of a concave ſphere, from which re-
mote objects appear at equal diſtances from us;
thus clearly to exemplify this fubject, if it were
poffible for you to be removed to the Planet Ve-
nus, our Earth would feem to be a ftar to your
view; but if you could be tranſported to a Pla-
net of another fyftem, our Sun would appear
as a Star, and its planetary Orbs would be invi-
fible,
D 5
Lady
58
On Aftronomy, &c.
}
Lady M. Pray inform me what you mean
by Conftellations?
Ment. The word Conftellation literally fig-
nifies a cluſter or affemblage of Stars: the an-
cients, in their progreffive improvements in A-
ftronomy, calculated feveral Stars which they
divided into diſtinct companies, or Conſtella-
tions; theſe they expreffed by typical figures,
according as their fertile imaginations fuppoſed
in their combined form they repreſented any
particular object, or had reference to fome im-
portant confequence.
Lady L. At what period did they make theſe
ingenious diſcoveries?
Ment. It is not in my power accurately to
determine that point; however it is very cer-
tain, that the ancients in the firſt ages of the
world, had fome knowledge of Aftronomy; as
the Conftellations Orion and Plecades are men-
tioned in the book of Job and it is generally.
ſuppoſed that book was written by Mofes, dur-
ing his refidence with Jethro, in the land of
Midian, above 1500 years before the Chriftian.
Era.
Lady L. I cannot imagine why ſuch names
fhould be given to the heavenly bodies, as they
bear no reſemblance to animals.
Ment
On Aftronomy, &c.
59
+
Ment. It may perhaps be in my power to
throw fome light on that ſubject, by endeavour-
ing to explain the invention of the Zodiac, by
which is implied a circle of animals, as that
term is derived from the Greek. The Zodiac
you are to regard as an imaginary circle, belt,
or zone in the heavens, that the Ecliptic divides
into two equal parts, which is terminated on.
either fide, by a circle parallel to it, at eight
degrees diſtance, in which ſpace or track the
Planets perform their revolutions. I fhall now
proceed to inform you of the probable means
which ſuggeſted theſe. aftronomical arrange-
ments: in the firſt ſtate of things we must con- .
fider the human race as being placed in a cli-
mate and condition fubjecting them to few
wants, for even the ſupply of which they could
not have recourfe to any foreign aid. Thus
circumſtanced, the first object of importance.
for them to effect, was the menfuration of
time, which could only be afcertained by the
motions of the heavenly bodies; the Moon was
the primary object of their attention, as by its
changes, and periodical returns, they could re-
gulate their affairs with the moft exact precifion,
though totally unfkilled in what is ufually called
Science; and the greatelt utility of theſe difco-
D 6
verics
60
On Aftronomy, Sc.
veries was) the enabling perfons at remote dif-
tances to affemble, for the purpoſes of divine
worship. As their obfervations were fimply
the effect of ocular demonſtration, they reckon-
ed the New Moon from the period they per-
ceived the Crefcent in the firmament; for which
purpofe they met in deferts, and on high places,
as the means of having a clear and extenſive
view of the horizon; and when they discovered
the Crefcent, they celebrated the Ncomenia, or
facrifice of the New Moon, followed by a feaſt,
of which the affembled families partook; the
food having been previously confecrated to the
Supreme Being. When any extraordinary
event occurred, they alſo inſtituted an annual
feftival, which was added to the Neomenia, and
celebrated with great folemnity. Thus you
movill perceive that the lunar revolutions formed
the first fyftem of religious rites, and the equal
diftribution of time; but as twelve of thoſe
were not fufficient to complete the regular re-
turns of the ſeaſons, it became neceſſary for the
ancients to obferve the particular ſtars under
which the Sun appeared to them to paſs every
month, which they divided into twelve equal
parts; and as they had no mathematical in-
itruments, they had recourſe to the ingenious
expedient
On Aftronomy, &c.
61
expedient of having two copper veffels, one of
which they filled with water, and by the pecu-
liar conſtruction of thefe utenfils, the water ran
from one into the other; therefore by accurate.
ly obſerving how many times this operation was
performed between the interval of each Star's
appearance, and the exact menfuration of the
quantity of water which alternately filled the
veffels, they acquired to a certainty the regular
proceſs of the heavenly bodies, which were their
only guides in the regulation of their facred and
civil concerns.
i
Lady L. In what part of the world were the
obfervations firft made, which you have enu-
merated?
Ment. In Chaldea, or Babylon, which you
will find clearly explained in my Sacred Hifto-
ry,
with maps to fhew you the exact fituation
of the regions inhabited by the patriarchal
tribes. It may be proper to remind you, that
in the primitive ſtate of things, the occupations
of the human race were principally of the paf-
toral kind; tending of flocks, herding of cat-
tle, and attention to agriculture, even in its
moſt laborious branches, were not then regarded
as degrading: ´neceffity fuggeſted the import-
ance of theſe purſuits, and cuſtom and habit re-
conciled
>
62
On Aftronomy, &c.
conciled thoſe who were higheſt in ſtation to
the general adoption of a plan in which their
wealth and happineſs were compriſed. This
courſe of life afforded the ancients many oppor-
tunities of making obfervations on the heavenly.
bodies, as the nature of the climate, and the
quality of their avocations, cauſed them chiefly.
to refide in tents, which being moveable habi-
tations, anſwered their purpoſe better than fixed;
dwellings, as they could conveniently change
their fituations for thoſe that produced the beſt
pafturage for their cattle, which required con-
ſtant attendance, and by that means enabled.
them to watch the revolutions of the Stars dur-
ing their nocturnal attendance on their flocks..
As knowledge of every kind is progreffive in its
operations, the Egyptians who were the moſt.
learned people at that early period, having ob-
ſerved the four natural divifions of the year, per-
ceived that the Sun in each of thefe divifions.
appeared to be placed fucceffively under diftinct
Stars; they confequently divided each of the
four ſeaſons into three Cantons of different.
Stars, and the whole year into twelve houfes, or
ſtations of the Sun, to which they gave the name
of different animals, to denote the quality of the
purfuits which were tranfacted in each particu-
lar
On Aftronomy, Sc.
63
1
lar period; and as they were very partial to
fymbolic figns, to exprefs any known object,
they had recourfe to that method to fignify their
different tendency and uſes; confequently this
evidently appears to have been the origin of
what is commonly called the Zodiac.
Lady M. I am extremely obliged to you
for explaining the firft difcovery of fuch an im-
portant and intereſting part of Aftronomy.
Ment. I fhall in the next place briefly en-
deavour to deſcribe why the ancients repreſent-
ed many of theſe Conſtellations, or figns, by
names and figures, the greater part of which are
of the animal kind. As in the early ages of
the world, the riches of its inhabitants confifted
in the abundance of their herds and flocks, they
naturally appropriated to each of the Stars that
appeared to them in regular rotation, appella-
tions which had an immediate reference to the
production of thoſe creatures, which conduced
to their fubfiftence, and conftituted their wealth.
The fpring Conftellations prove this affertion
beyond a doubt; the firft in order is Aries, or
the Ram, as at that ſeaſon, the month of
March, their lambs were brought forth. This
Conftellation was therefore fo named, as the
means of teaching them to expect that advan-
tageous
+
64?
On Aftronomy, &c.
tageous event, when that particular Star was
obferved; in like manner Taurus, the Bull, in
April, was to fignify that at that period their
cows produced calves; the next Conftellation
Gemini, or the Twins, in May, was a type or
fimilitude of the fecundity of their Goats, which
ufually had two kids at a birthe
Lady L. How clearly this appears. I am
much entertained by the information you have
fo kindly imparted.
Ment. I am now come to the fummer Con-
ftellations, Cancer, or the Crab, which appears
in the month of June, was fo denominated, as
á type that the Sun-appeared when he had gain-
ed that point in the heavens, to recede or have
a retrograde motion, which they expreffed by
the figure of a Crab, as that animal crawls.
backwards: this is what is called the Summer
Solſtice, when the Sun is apparently at his great-
eſt height, and the days conſequently the longeſt
in the Northern Hemisphere.
Lady L. What apte fimilitudes the ancients
had recourſe to, as means to exprefs the affinity
and reſemblance that different objects bore to
their ſtate and condition.
Ment. The remaining fummer figns next
preſent themſelves for our confideration, Leo
On Aftronomy, St.
650
the Lion, which appears in the month of
July, was fo called to denote the heat of
the weather at that feafon; which was typic
fied by the fury and rage of a Lion. We
next find Virgo or the Virgin, in the month
of Auguft, which was the emblem of their har-
veſt, it having been the practice from the earli-
eft periods for gleaners (who were ufually fe-
males) to collect all the corn that was left on the
ground by the Reapers.
Lady L. I fhall be forry when you have
finiſhed your account of the Conftellations. I
had no idea they were fo interefting.
Ment. The autumnal Conſtellations are the
next branch to be confidered. Libra or the ba-
lance in September, is a literal type of the equali
ty of the days and nights at that ſeaſon, uſually
called the autumnal equinox; which could not
be better expreffed than by the reprefentation of
a pair of fcales. The next is Scorpio or the
fcorpion; which appears in October, and is fo
called to denote the baneful difeafes which in
thofe regions often raged with violence at that
ſeaſon, which were aptly compared to the fting
of a ſcorpion. Sagittarius or the archer, that
makes its appearance in November, was a token
to purſue the avocation of hunting, which was
neceffary
لامية
66
On-Aftronomy Sc.
neceſſary in a country at that time fo thinly in-
habited, effectually to clear the defarts and for-
efts of wild beafts and noxious animals before
the approach of winter.
Lady M. The wife application the ancients
made of theſe advantages does thein great credit..
Ment. The first of the winter Conftella-
tions is called Capricornus or the goat, which
appears in December, and derives its name to
exemplify the declenfion of the Sun at this pe-
riod, which is what is commonly called the.
winter folftice, when the days are at the fhort-
eft pitch in the Northern Hemisphere; there-
fore its appellation is remarkably appropriate, as
it is the peculiar quality of the goat to climb
the higheſt precipices; therefore the ancients
choſe this fimilitude, to exemplify the know-
ledge they had attained that the Sun would for.
the ſpace of fix months gradually advance till it
had gained its higheſt elevated ſituation. Aqua-
rius or the water bearer, in January, is a lively
type of the fucceffion of rain, fnow and hail
which frequently characterizes that ſeaſon; and
laftly, the Conftellation Pifces or the fishes, in
February, equally denoted that the fish as a na-
tural confequence, at that period when their.
native element is more abundant, is from that
effect in the greateſt degree of perfection: thus
you
On Aftronomy, &c.
67
you will perceive that the ancients who had no
almanacks, and not even an alphabet, were en-
abled by theſe fymbols to regulate the diviſion
of time, aſcertain their annual purſuits and ex-
pectations with as much precifion as we, who
by the aid of fcience can keep regular accounts
and tranfmit our ideas and fentiments to diftant
regions: but we must ceafe to wonder when
we reflect that the Heavens were to them an
index on which all uſeful neceffary information
was legibly infcribed.
Lady L. My dear Mentoria, my admira-
ration of theſe clever people is loft in adoration
of the Supreme Being, who wifely ordained
theſe diſcoveries to be made.
Ment. The world would have been a mere
machine of chaos or confufion, had not the
goodneſs of God infpired his frail creatures
with the means of reducing his diffuſed bleffings
to a general ſtate of order, a leffon that is forci-
bly inculcated by the obſervation of the celeſtial
luminaries, which are uniform in their courſe,
and manifeſt the wiſdom and omnipotence of
their great Creator.
Lady L. I am ſurpriſed to hear you men-
tion the Sun as a body that changes its fituati-
on
; I recollect your informing me it was ſtati-
onary in the centre of the folar fyftem.
Ment.
68
On Aftronomy, &c.
Ment.. The Earth's revolution as a Planet,
and alfo on its own axis, were circumstances
that were diſcovered long after the divifion of
the year adopted by the Chaldeans and Egyp--
tians. In the firft ages of the world there is
no doubt the inhabitants imagined the Earth
was a plane or flat furface, and that the Sun
conſtantly moved its pofition and reſumed its-
courſe, which produced to them the fucceffion.
of day and night, and the viciffitudes of the
feafons this was a very natural conclufion, as
the mere fuggeftions of perception could not
convince any perſon unenlightened by ſcience,
that the Earth is in conftant motion, and that
its, progrefs round the Sun is rapid beyond our
finite comprehenfion. It may perhaps in fome
meaſure conduce to your amufement, and tend
to your improvement if I trace the regular gra-
dations which operated to, bring Aftronomy to
its prefent ftate of perfection. Induſtry, and ex-
perience are the grounds of the moſt uſeful
knowledge, the one is a fpur to action, the
other a guide to valuable achievements.
•
Lady L. I promiſe myſelf much pleaſure
in hearing, your account of the progreſs of ſo
intereſting and fublime a ſcience.
Ment
ม
On Aftronomy, e.
69
>
Ment. Thales the Mileſian about 580 years.
before the Chriſtian Era, was the first philofo-
pher who taught Aftronomy in Europe; he had
gained fuch a degree of perfection in the fcience,
he calculated eclipfes of the Sun and Moon,
and diſcovered the rotundity of the Earth. Py-
thagoras a Greek Philoſopher diſtinguiſhed him-
felf about 50 years after, who, no doubt, from
the obſervations Thales had made, had a clear
idea of the revolutions of the celeftial bodies,
which fuggefted to him the probability that the
Earth was in motion, and that the Sun remain-
ed ſtationary as this opinion was contrary to
the general belief or perception, this new ſyſ
tem gained no great progrefs, nor was ever much
eſteemed by the ancients. As the means of re-
conciling this contrariety of fentiments on fo
important a branch of philofophy, the moſt learn-
ed men at that period endeavoured to eſtabliſh
an intermediate ſyſtem; therefore Ptolemy an
Egyptian philofopher, who flourished above 138
years before Chrift, formed a ſyſtem which he
conſtructed on a plan to reconcile the contending
parties. His opinions tended to confirm that
the Earth was fixed immoveably in the centre
of the Univerſe; that the feven Planets (confi-
dering the Moon as one of the primaries) were
placed
1770
On Aftronomy, &c.
placed near to it; above them he afferted was
the firmament of fixed Stars and chryftaline
Orbs, then the Primum Mobile, by which you
are to underſtand the first principle of motion;
and lastly, the Coelum Emperium or Heaven of
Heavens. All theſe immenfe Orbs he ima-
gined moved round the Earth once in 24 hours ;
as the means of accounting for theſe revolu-
tions, he conceived a number of circles called
eccentries and epicycles croffing or interfect-
ing one another, confequently perpetually inter-
fering in their progrefs; this fyftem was uni-
verfally received from the time of Ptolemy to
the revival of learning in the fixteenth century.
It is uncertain by whom artificial globes were
invented, yet it is clearly known that Hippar-
chus, and Archemides, about 200 years before
the Chriftian Era, by their reſpective im-
provements in Geometry and other branches of
the Mathematics, rendered the ufe of the
ſpheres to be relied on, by making them corref
pond with the afpect of the Heavens, and the
motion of the Stars.
Lady M. I cannot expreſs how much I ef-
teem myſelf obliged by the inſtructions you give
us; I hope effentially to profit by fo much uſe-
ful information.
Ment.
On Aftronomy, &c.
71
Ment. Notwithſtanding the Europeans were
in ſome degree emerged from the abyſs of total
ignorance; yet fcience or what we rank as
knowledge was but in the dawn of its luftre;
prejudices prevailed, which gradually abated as
bigotry declined and the errors of religious faith
were vanquished by the firm eftabliſhment and
happy effects of the reformation. Previous to
that event learning was chiefly poffeffed by the
heathen Philofophers, who advanced certain in-
genious opinions and moral precepts in their
fchools; and in times not quite fo remote, by
Monks and Friars, whofe intereft it was to
keep the community in a ſtate of profound ig-
norance; as when once the human mind became
enlightened, their dominion was at an end.
Lady L. How thankful we ought to be that
we live in an age fo confpicuous for the attain-
ment of every deſirable acquiſition.
Ment. I must now proceed to inform you
that Copernicus, a native of Poland, who was
of an enterpriſing eccentric genius, about the
period Anno Domini 1530 ventured to adopt
the Pythagorean or true fyftem of the Univerſe:
this doctrine, however juft in its principles,
had been fo little attended to, that the Philofo-
pher who was the inftrument of its reſtoration
- was
*7 2
On Aftronomy, &c.
:
confidered by the generality of perfons, as the
inventor or founder of the fyftem, which from
thence obtained the name of the Copernican
philofophy. The religious feuds and the com-
bined ſelfiſh views of the profeffors of Chrif-
tianity at that period, greatly tended to check
the eſtabliſhment of a theory which has fince.
been found to have been formed on a rationa]
bafis. The controverfy which arofe from fome
perfons embracing and others rejecting the fyf-
tems I have enumerated, gave rife to many ab-
furd opinions reſpecting the oeconomy of the Pla-
netary Orbs In this ftate of difputation, Ty-
cho Brahe, a Dane of noble extraction, being
convinced of the defects of the Ptolemaic fyf-
tem, but averſe from acknowledging the mo-
tion of the Earth, attempted about the year
1586 to eſtabliſh a new theory of his own fabri-
cation, which was ftill more complex and incon-
fiftent than the one formed by Ptolemy. The
principal opinions he advanced were, that the
Moon had a monthly motion round the Earth
as the centre of its Orbit: the Sun he confi- -
dered as the centre of the Orbits of Mercury,
Venus, Mars, Jupiter and Saturn. The Sun
he fuppofed with all theſe Planets revolved round
the Earth in a year, and even once in the ſhort
1pace
}
On Aftronomy, St.
73
fpace of twenty-four hours; this fyftem, not-
withſtanding its palpable errors, met with many
advocates, and Longomontanus fo far improv-
ed and refined upon its tenets, as to admit of the
diurnal motion of the Earth, though he denied
its annual revolution. This we muſt allow
was one eſſential point gained, and was un-
doubtedly the infant ſtate of that philoſophical
perfection which was attained in the 17th cen-
tury, in which fcience may have been faid to
have gained its meridional height. About the
year 1610 Galileoa Florentine, whom I have pre-
viouſly mentioned as being the means of firſt
applying teleſcopes to aftronomical purpoſes, dif-
covered new arguments to prove the motion of the
Earth, which tended to confirm thofe before ad-
vanced; but as thefe opinions were under the
influence of Papal authority, thought inconfif-
tent with the religious principles he profelfed,
Galileo was compelled to renounce theſe rational
ideas, as they were confidered a herefy or offence a-
gainst the Church, though in effect only like every
other branch of knowledge militating againſt
its ufurping oppreffive miniſters or priests. In
this ftruggle, or ſcientific conflict, it remained
for one fuperior genius to complete what fo
many had endeavoured in vain to compafs with
E
permanent
-74
On Aftronomy, &c.
#
permanent effect, and this honour was reſerved
for Sir Ifaac Newton, who flouriſhed about the
end of the 17th century. This eminent philo-
fopher was a native of Great Britain, and was as
much eſteemed for his private virtues, as admired
for his diftinguifhed eminence in the moſt pro-
found and occult branches of fcience: as he was
- a good man in the moſt comprehenſive ſenſe of
the word, and a zealous fincere chriftian, his
reſearches all tended and co-operated to diſplay
his reverence for the Supreme Being, whofe
works which fhine with fuperior glory in the
Heavens, he traced with accuracy, and defined
with a degree of precifion which have rendered
his fame immortal. It is to the labours of this
renowned Philofopher we are indebted for ob-
taining just conceptions of the various proper-
ties and motions of the celeftial bodies, and alfo
for the diſcovery of the principles of the general
law of Nature which regulates their reſpective
revolutions. This law is termed Gravity or At-
traction, and is the fame by which any body
falls to the ground when difengaged from what
ſupported it. The univerfal gravitation of
matter to its common centre is a general princi-
ple, and may be traced in regular gradation as
to its effect, from the Planetary ſyſtem to the moſt
incon-
On Aftronomy, &c.
75
inconfiderable object on the terreftrial globe as
every particle gravitates or tends to its central
point, which is produced by the powers of At-
traction. It has been clearly demonſtrated that
the natural effects of Attraction and Gravitation
keep the fea in its due bounds, and alſo the va-
rious bodies which cover the furface of the
Earth from flying into the air; it has the fame
operation on every part of the univerſe, confines
the Planets in their proper Orbits, and pre-
ferves the whole fabric of Nature from diforder
and confufion. I have expatiated very fully on
the advantages we have derived from Sir Ifaac
Newton's valuable difcoveries, and cannot a-
dopt any better means for concluding his de-
ferved eulogium, than by citing Pope's concife
epitaph, which in a fmall compafs implies the
fuperior luftre of his genius and fame.
Nature, and Nature's laws, lay hid in Night;
God faid, let Newton be, and all was Light!
Lady M. I admire the account you have
given of Sir Ifaac Newton, and am much o-
bliged to you for quoting the epitaph, which fo
fully expreffes the great effects his genius pro-
duced. I fuppofe when firſt theſe philoſop
E 2
IS
talked
$6
On Aftronomy, &c.
•
talked of the Earth moving, they were thought
abfurd, and very few believed them.
Ment. In all inflances, when the human
mind is converted from chaotic ignorance, the
firft effort must require ftrong conviction to ef-
face the influence of prejudice and fixed habits
of thinking; yet when facts are clearly de-
duced, and opinions embraced, on the evidence
of reaſon, rays of knowledge diffuſe their light
and become objects of admiration and belief.
Perfons whofe minds are uninformed, are not
always credulous, and apt to receive new opi-
nions; fufpicion and ignorance go hand in
hand, which are material obftacles to effential
improvement and the general diffufion of know-
ledge. I remember in the courſe of my read-
ing to have met with a remarkable proof to this
effect, in the following inftance.
To the best of my recollection, an ambaſſa-
dor was fent from a Northern Potentate, to a
Prince in fome torrid region, who naturally
enquired for an account of the country he came
from. When the ambaffador defcribed the fea
as frozen, and the ground covered with fnow,
which he repreſented as a beautiful white fub-
ftance, the ignorant Prince difmiffed him,
and fent him back with this meffage, that he
could
On Aftronomy, Sc.
77
could not think of forming any treaty with a
nation whoſe minifter was fuch a notorious
liar. Another fact may alfo be produced of a
fimilar tendency. When St. Paul was plead-
ing his caufe before king Agrippa; whilft he
was difcourling on the refurrection of the bo-
dy, Feftus called out with a loud voice, “Paul
thou art befide thyself, much learning doth
make thee mad"! Thus we perceive in both the
inſtances I have ſpecified, ignorance proveď a
bar to conviction.
Lady M.
Yet I can hardly blame the
Prince, as the country he lived in prefented no
fuch objects, as the ambaffador defcribed; and
I imagine Feftus, as he was not a Chriſtian,
did not believe in the Refurrection.
Ment. The evidence or belief of circum-
ſtances beyond our comprehenfion, in religious
fubjects, is produced by what is theologically
called Faith, which is indifpenfibly required in
all matters concerning the promiſes of God,
and the facts that are related in holy writ. In
circumftances of leffer importance, we ſhould
ever give credit to refpectable teftimonies; as
our ideas muſt be very contracted, if we only
believe what we fee, or what we hear, which
comprehends what is ufually called ocular and.
E 3
auricular
On Aftronomy, &c.
auricular demonſtration, or proof. Philofophy
clears the path of profound ignorance, by plant-
ing knowledge in the various departments of
Science and other general vehicles of inftruction;
and Revelation removes every doubt, and affords
every hope a reaſonable being can form. Even
the Reſurrection of the Body, which was a ftum-
bling block to Feftus, who was a Heathen, ist
a beacon of hope to a devout Chriftian; nor
can the intellectual powers doubt, which per-
ceive vegetation renewed, though apparently in
the indiffoluble bands of death, but that in a
future ftate their own exiftence will bloom,
through the endlefs ages of eternity.
Lady L. I am greatly obliged to you for
placing thefe obfervations in a point of view to
impreſs on my mind a due fenfe of their impor
tance; as knowledge is fuch a valuable acquifi-
tion, I am furpriſed any perfons remain in a
ftate of ignorance.
Ment. A variety of circumftances confpire
to check the zeal for attaining this treaſure; in
the firſt place there are many who do not poſſeſs
the means, and others neglect thoſe opportuni-
ties which are afforded them. Perfeverance is
a neceffary ingredient in compaffing this defi-
rable end, yet but few comparatively have re-
folution
On Aftronomy, 79
+
Sc..
}
folution to apply cloſely to any particular ſtudy,.
and thoſe who are furrounded by objects to ex-
cite uſeful enquiry,, are often too fupine, to turn
them to dục advantage. How many with ex-
tenfive Gardens,, ftored with native and exotic
Plants, neglect the ftudy of Botany? How
many with Libraries amply furnished with the..
productions of the beft authors, read only trafh,
the offspring of fome flippant. writer? How
many, furrounded by all the beauties of Nature,
defpife their fimple yet majestic charms, and
devote their time and attention to all the delufive
fripperies of Art? Thele much to be lamented.
truths, are the primary fource of depraved or
uncultivated intelle&ts; as the foil or quality of
the understanding is of fuch a nature, that if
we neglect to adorn it with fruits and flowers,
it will ſpontaneouſly be over-run with noxious.
and baneful weeds.
Lady M. It fhould infpire us with grati
tude, that we receive an Education that incul-
cates all important branches of knowledge.
Ment. The learning you fhould be zealous
to acquire, confits of that genuine kind of in-
formation that will bear the test of critical in-
veftigation. There is a fpecies of fuperficial
knowledge, that may be compared to tinfel,
E 4
which
80
On Aftronomy, &c.
which is glaring in effect, without poffeffing
any real luftre, and when put in competition with
fterling gold, bears no proportion in intrinfic
value. Let your purſuits be well directed, and
your application uniform; as wiſdom is not to
be acquired by flights of fancy, but muft be
fought with ardour, and cheriſhed by reflec-
tion.
DIALOGUE
NORTHERN CONSTELLATIONS.
CONSTELLATIONS.
Urla Major, or Helice....
Urfa Mi or....
Draco
Cepheus.....[and Chari)
ENGLISH NAMES.
The Greater Bear
The Leffer Bear
The Dragon.
•
Canes Veuatice (Afterion, The Hounds
Booles
+
Mons Menalus
Coma Berenices
Cor Caroli ..
•
Corona Borealis.
Hercules, or Engonafi……….
Cerberus
Lyra, or Vultur Cadens.
Berenice's Ilair
Charles's Heart
The Northern Crown
The Lyre ..
The Swan
PRINCIPAL STARS
Alcor, fmall one in l.
Dubhe, in reck. Aliath, and Benenatch, in tail.
Cynofura, (the Polar Star) in tail. Kochab, in neck.
Ras Tabin, in head.
Alderamin, in left fhoulder.
Arcturus, in coat. Ceginus, in right fhoulder. Mirach, in belt.
Alphacca, or Lucida Coronæ.
Ras Al Giethi, in head. Rutilicum, in left ſhoulder. Marfic, in club. Maafym,
in right arm.
Lucida Lyræ,
Deneb Adigege, in tail. Agilfage,
Albirco, in beak,
Cygnus..
Vulpecula.
Anfer...
Lacerta Stellio.
Caffiopeia..
Camelopardus
The Fox
The Goufe
The Lizard
Shader, in breaſt.
The Camelopard
Serpens, or Ophiuchi.... The Serpent
Serpeaturius,or Ophiuchus
Scutum Subiefki
Aquila, or Vuitur Volans
Antinous, or Ganymedes
Delphinus.
Sobicfki's Shield
The Eagle
The Dolphin
Equulus
Sigilla...
Andromeda
Perfeus
Ras Al Hague, in Head. Yed, in right hand.
Alcair, or Atair, in neck.
The Little Hoife
The Arrow
Caput Andromedæ, in head. Migar, in belt. Almaak, in right foot.
Caput Medufæ, (Medufa's Head) a Clufter, Algol, in Caput Medufæ.
Enif, in nole. Marhab, in thoulder. Scheat Alpheus, in left leg.
Capella, in the Goat. Hædi, the Kids.
[in fide.
Algenib,
Pegafus..
•
Auriga
The Charioteer
Lynx
Leo Minor...
Triangulum
Triangulum Minus.
Mufca
-
The Leffer Lion
The Triangle
The Little Triangle
The Fly
CONSTELLATIONS IN THE ZODIAC.
CONSTELLATIONS
Aries
·
Taurus
Gemini
Cancer
Lco
Virgo
Libra
-
.
-
Scorpio
Sagittarius.
Capricornus
Aquarius
Pifces
-
ENGLISH NAMES.
ာ The Rarn
8
= 36 = ∞ 3 Signs,
The Bull....
The Twins.
The Crab
•
The Lion..
mp The Virgin...
The Balance.
m The Scorpion.
The Archer
The Goat
...
PRINCIPAL STARS.
Hyades, cluſter in face.
Pleiades, a clufter in the neck.
Caftor and Pollux, in the head of the Twins.
Præfepe, in back.
Regulus, or Cor Leonis, heart.
Vindemiatrix, in right ſhoulder.
Zuberefehemali, in right fcale.
Antares, or Cor Scorpii, heart.
Nebulofæ, in noſe.
Deneb Al Gedi, in tail.
[eye) one of the Hyades.
Aldebaran, (the Bull's
Deneb Al Affad, in tail.
Spica Virginis, wheat in right hand.
Zuberelgenufi, in left fcale.
Lefath, in tail.
The Water-Bearer... Scheat, in leg. Fomalhaut, laſt in the water.
The Fishes
Nodus Celeftis, the knot of the ribbon.
Theſe are the Signs of the Zodiac. The fix fift are called the Northern Signs, and the fix laſt the Southern.
CONSTELLATIONS.
Cctus..
Eridanus.
Phoenix
Toucan
SOUTHERN CONSTELLATIONS.
ENGLISH NAMES.
The Whale...
PRINCIPAL
STARS.
Menhar, in mouth. Batan Ketus, in fide. Deneb Ketus, in tail.
Acheinar.
Orion
Rigol, in right foot.
Bellatrix, in right shoulder. Betelgeuge, in left shoulder.
Monoceros
The Unicorn
•
·
Canis Minor
The Lefler Dog..
Procyon, in fide.
A pus
Hydra.
Sextaus Uraniæ
Crater.
Corvus
Centaurus.
-
Lupus
Ara
Tr.angulum Auftralis..
Pavo
Corona Auftralis
Grus
Pifcis Auftralis
Lepus
Columba Norchi
Robur Catoli.
Crux
Argo Navis
Canis Major.
Ápís
Irundo
Indus
Cameleon
Pifcis Volans.
Xiphias...
The Cup...
The Raven.
The Centaur
The Wolf
The Altar
Alphard, or Cor Ilydiæ, heart.
Alches, in ftand.
•
Algorab, in right wing.
[gle
The Southern Trian-
The Peacock
The Southern Clown
The Crane
The Southern Fiſh
*
The Hare
Neah's Dove
Charles's oak (Crofiers
The Crofs, fometime,
The Ship A o..
The Greater Dog
-
The Bee
The Swallow
The Indian
The Flying Fiſh
The Sword Fith
D
Canopus.
Sorius, (the Dog-Star) in mouth. Ifis, in right car.
DIALOGUE IV.
THURSDAY.
On the Succeffion of Day and
Night, and the Viciffitudes
of the Seaſons..
WE
Lady Mary.
HAT will now be the fubject of your
inftructions, my dear Mentoria? I.
was ſo well pleaſed with your obſervations on
the fixed Stars and the Zodiac, I anticipate.
much entertainment from the next object you.
are inclined to explain.
Mentoria. It appears neceffary to make fome
remarks on the regular fucceffion of Day and
Night, the viciffitudes of the Seafons, Eclipfes,
E 5
and
82
On the Succeffion of
and Tides, as they are immediately connected
with the foregoing obfervations on the Solar
Syſtem; though I fhall be lefs copious on thoſe
fubjects, as by my former inftructions, I fat-
ter myfelf with the hope, you are tolerably well
informed reſpecting thoſe intereſting particulars.
The revolution of the Earth on its own Axis,
produces what is ufuallycalled its diurnal motion,
which it performs in the ſpace of 24 hours.
In the courſe of this revolving rotation, whilft
that part of the Globe we inhabit is turned
toward the Sun, we are confequently cheered
by his beams, which conftitutes our day; in
like manner, when the Earth is turned from the
Sun, we are involved in darkneſs, which
makes our night, whilft the other Hemifphere-
enjoys day: thus you will perceive that they
are both alternatively enlightened.
Lady Louifa. I clearly comprehend what oc-
cafions the regular rotation of day and night;
But with to know by what means morning, and
evening, are produced.
Ment. In confequence of the Sun's great
magnitude and diſtance, the rays of light he
émits, fall in a parallel direction on the Earth,
which invariably illuminates one of her Hemif-
pheres, therefore whilſt any place on the Globe
continues
Day and Night, &c.
83
continues in the darkened part, it is night in
thoſe regions, but as foon as that place, by the
diurnal rotation of the Earth from Weft to
Eaft, approaches to the verge of the enlightened
Hemifphere, what is ufually called day-break
or Morning, appears. In the Earth's rotation
on her own Axis alfo, when the meridian of
that place is brought beneath or under the Sun,
it' is then ſaid to be Noon there and at every
other place of the fame meridian; in regular
progreffion as this place advances in the Earth's
revolution, it again reaches the boundaries of
the darkened Hemifphere, which produces the
dufky fhades of Evening, and in uniform gra-
dation, the return of Night.
Lady L. In our lectures on Geography, I
recollect fome of the circumftances you have
juſt recited.
Ment. Aftronomy may be confidered as the
counterpart of Geography; as merely being
acquainted with the form of the Earth, and
the fituation of different countries, would be
a very imperfect kind of knowledge. When
you hear on what part of the Globe any par-
ticular place is fituated, you become interested,
and wish to be informed, whether it is hot or
cold, and what allotment of light, and other
E 6
comforts,
84.
On the Succession of
comforts, the inhabitants enjoy: theſe can
never be accurately afcertained, unleſs you are
in fome degree inftructed in Aftronomy, which
would enable you to calculate what influence the
light and heat of the Sun, have over it, and
give you a clear idea of its temperature, length
of day, and natural productions. For example,
we will fuppofe an ignorant perſon to be in
company, and that Greenland, and Guinea,
fhould be the ſubject of converſation, he would
form no conception whether the inhabitants
were fcorched by heat, or frozen by cold:
whilſt the well-informed would have a perfect
knowledge of the oppofite qualities of each
reſpective region.
-
Lady L. By what means could this know-
ledge be attained?
Ment. They would recollect that Green-
land is in the frigid, and Guinea in the torrid
zone. That the former from its remote North-
ern ſituation muſt be intenfely cold; and that the
latter by being fituated between the tropics,
where the influence of the Sun is ſo great, con-
ſequently is ſubject to intenfe heat. They
would alſo know that beyond the arctic circle,
the inhabitants of thofe regions in Summer, have
a progreffive portion of day-light, from one
month
Day and Night, Sc.
85
.
Ć
month to fix, and in Winter the fame portion
of darkneſs or night. They would alſo be ſen-
fible, that thoſe who refide in the torrid zone,
have not days of any confiderable length, as the
days and nights are uniformly equal in thofe
countries that are fituated immediately under
the Equinoctial line, and that from that ſpace
to the arctic circle, which is the boundary of
the Northern frigid zone, there are 24 climates,
each of which increaſe by half an hour in the
length of each day, which may be eaſily calcu-
lated with certain precifion, and it may be
proper to obferve the fame effects at contrary
periods occur, in the Southern frigid zone.
Lady M. I fhould not wish to live in Gui-
nea, or Greenland.
Ment. Undoubtedly a ſtation between thoſe
two extremes is more agreeable; yet I make
no doubt, each party are fatisfied with their
allotment. In the torrid zone Providence has
amply ſupplied the inhabitants with an abund-
ant portion, of bleffings, to conduce to their
comfort, which in' a great meafure are fponta-
neous. In fome places gold is found in fuch
plenty in the beds of the rivers, it is not
neceffary to work the mines, which produce
that valuable metal.
Lady
86
On the Succeffion of
Lady L. I think it would be very defi-
rable to live where there is fuch abundance of
gold."
Ment. In an uncivilized country, gold is
of itſelf of no intrinfic value to the native pof-
feffors; as it obtains its confequence and worth
by being the medium to procure us the necef-
faries and conveniences of life, which is evi-
dent, as in fome of the countries where this
metal abounds in its genuine ſtate, the ignorant
primitive inhabitants were rejoiced to exchange
it for glafs beads, and other ornaments, and
implements of no comparative degree of value.
The importance of a poffeffion, depends on the
circumftances of our condition; thus to a
Savage, who is not fkilled in mechanics, an
iron hatchet is a more valuable acquifition,
than an ingot of gold.
Lady M. I perceive this very forcibly, and
do not envy theſe people their poffeffions; yet:
I think they are better provided for than the
Greenlanders; as I have often read of the
hardſhips they undergo,
Ment. The great Creator of the univerſe,
has difpenféd a degree of provifion for all the
inhabitants of the Earth, fuited to the peculiar
ftate of each region; it is true, each diſtrict
does
1
Day and Night, Pt.
89
does not appear to poffefs an equal portion of
thoſe things we confider as effential to happi-
nefs; yet the eſtimation of bleffings depends
more on the force of habit, than their intrinfic
quality. The Greenlanders as inhabitants of
the frigid zone, have but few reſources in the
article of food. Fish, Seals, Sea-fowl, and
Rein Deer, form the chief of their fubfiftence,
and their train oil which we could not eat,
is eſteemed a luxurious addition to their fim-
ple repafts.
Lady M. Why are Whales found more
frequently in the Northern, than any other
Seas?
Ment. They are not peculiar to the North-
ern frigid zone, as many are found alfo in the
Southern; Providence has wifely ordained that
the fish which inhabit the Seas, in the frozen
zones, are furniſhed with a very large portion
of fat, or blubber, which by a due preparation,
is converted into oil, being thus liberally endu-
ed with this.unctuous ſubſtance, enables Whales,
Seals, &c. &c. to fubfift where the ocean is
frozen, as fat renders animals that are clothed
with it in a very great degree not very ſuſcep-
tible of cold: thus you fee in this, as in every
other inftance, the wife Creator of the univerfe
has
88
On the Sacceffion of
has fitted each creature to its allotted ſtation.
I must now cloſe this long digreffion, and pro-
ceed to give you fome account of the variations.
of the Seafons.
Lady M. I expect much entertainment.
from that fubject, and will not interrupt you,.
except to requeft you will accept my beft.
thanks for the improvement you have already
imparted.
*
',
Ment. The feafons which confift of the
regular fucceffion of Spring, Summer, Autumn,
and Winter, are produced by the Earth's an-
nual motion round the Sun, which not being
in the plane of the equator, but in an Orbit
inclined to it in an angle of 23 degrees and
half, as the Earth turns from Weſt to Eaſt.
The Spring is the feaſon of the year firſt to
be confidered, at this period, in this fituation
of the Earth, the equator is oppoſed to the Sun,
and in confequence of his always enlightening
a Hemiſphere or half the furface of the globe,
his light by being now equally divided, reaches
to both the Poles: therefore from the diurnal
revolution of the Earth, the days and nights are
equal at all parts,
{
Lady
Day and Night, Sc.
89
Lady M. I recollect your informing me
that the fign Aries, or the Ram was the vernal
or ſpring equinox.
Men. When the Sun enters the oppoſite
fign Libra or the balance, it produces the fame
effects reſpecting the equality of the days and
nights, and is hence called the autumnal equi
nox.
Lady L. I will remember to obferve theſe
circumſtances when the proper period arrives.
>
Ment. We must now examine the proper-
ties of Summer; in order to give you a clear
idea of this feafon I muſt obſerve when the
Earth has advanced in its Orbit through Libra,
Scorpio, and Sagittarius when it arrives at the
first degree of Capricorn, the North Pole is
turned to the Sun, and the tropic of Cancer is
oppofite to him; and as the inclination of the
Earth's Axis is 23 degrees and an half, juſt ſo
far the rays of the Sun reach beyond the
North Pole, and in the fame degree are defec-
tive at the South Pole; confequently the whole
of the Arctic circle is enlightened and the Ant-
arctic circle deprived of light: from which it
will clearly appear to you that in the Northern
Hemiſphere it is the longeſt day which confti-
tutes Summer, and in the Southern half of the
Globe
4
90%
On the Succeffion of
Globe the shorteft day, or Winter; but under
the Equator the days and nights are uniformly
equal, confifting of twelve hours each, which
comprehends the twenty-four hours that is the
period of the Earth's rotation on her own
Axis.
Lady M. I had not before a clear notion
that when it is our Summer the inhabitants, of
the contrary Hemiſphere have Winter.
Ment. This is a natural confequence, as at
the period the Earth is proceeding from the fign
Libra or the balance, the North Pole is ap-
proaching towards the Sun, whilft the Southern
Pole recedes from him; therefore the length of
the day is increafing in the Northern Hemif
phere and declining in the Southern. In the
fpace of three months the ſcene will be wholly
changed, for as the Sun will then be over the
Equator, both Poles will again be enlightened.
by his rays, and the day and night confequently
equal in every part of the Globe. The Sun at
this ſeaſon will be rifing to the
ting to the North; this is what
tumn.
{
South and ſet-
is called Au-
Lady L. The fituation of the Sun and
Earth which produces the equality of days and
nights in the period you have, been defcribing, I
fuppofe
Day and Night, Gr.
92
fuppofe is what is called the Autumnal Equi-
nox.
Ment. Undoubtedly, and as the Earth ad-
vances towards Winter, the South Poles will be
turned to the Sun, and the North Pole from
him; therefore when the Earth is in the fign
Cancer it is Summer in the regions to the ſouth
of the Equator at the period when it is our
Winter this you will perceive is occafioned by
the Sun's being over the tropic of Capricorn,
which is as many degrees fouth of the Equator
as the tropic of Capricorn is to the north of it
when the Sun was in our Summer; at this pe-
riod the Antarctic circle is enlightened and the
Arctic obfcured in darkneſs, but under the
Equator the days and nights are equal. The
Sun continues above the horizon of the ſouth
Pole till the vernal Equinox, when he wil
again rife to the north Pole, and with unceafing
regularity fulfil the rotation of the fucceffive fea-
fons.
Lady M. I cannot exprefs how much I ad-
mire the variety that we experience in the dif-
ferent effects of the feafons, as they change in
annual regularity and order.
Ment. If the Axis of the Earth were per-
pendicular to the plane of the Earth's Orbit,
the
92
On the Succeffion of
the days would be invariably of the fame length
and we ſhould have no diverſity of ſeaſons.
Lady M. That would be very agreeable,
I ſhould like always to have the feafons like
ſpring or autumn, and the days never ſhort-
er: pray what would produce that effect?
Ment. The Sun being over the Equator,
which muft at all times enlighten both Poles of
the Earth, and would make the days and nights
conſtantly equal, as their variation is produced
by the inclination of the Earth's Axis and its
preſerving its paralleliſm, by which term you
are to underſtand, the Earth keeping its Axis.
in its natural revolution round the Sun in a po-
fition always parallel to itſelf, which it nearly
does. When the Sun is in the first point of
Aries, the Earth must be in the beginning of Li-
bra, as that is the oppoſite fign.
Lady L. How much I pity the inhabitants
of the frigid zone, becauſe in winter they have
fo great a portion of darkneſs.
*
Ment. This apparent evil is mitigated by
the kind hand of Providence, as even under the
Poles when the Sun is not vifible to them, they
are but a ſhort time involved in abfolute dark-
nefs; as the twilight continues till the fun is
18 degrees below the horizon, and his greateſt
depreffion
Day and Night, &c.
93
dèpreffion is but 23 degrees and an half, equal to
the inclination of the Earth's Axis. The Moon
í
alfo is above the horizon of the Poles for about
the ſpace of a fortnight, being half her period
North and the other South of the Equator;
therefore as the Moon at full is in the fign
oppofite to the Sun, the tropical full Moon
muſt be 24 hours above the horizon at the Po-
lar circles.
Lady M. I cannot fufficiently admire the
goodneſs of God in diſpenſing ſuch alleviating
mercies to the inhabitants of ſuch unfavourable
climes.
Ment.
Theſe beneficent effects may be
traced in every inftance: the Sun, which conti-
nues longer above the horizon in Summer than
in Winter, enlivens our purfuits: but as a
counterbalance for the comparatively ſhort por-
tions of his rays that we enjoy in Winter, the
Moon at that ſeafon continues longer viſible to
us than in Summer when we ftand lefs in need
of her aſſiſtance. You will perhaps ſcarcely
believe that in the height of our Summer, we
are farther from the Sun than in Winter.
Lady L. How can that poffibly be? I muſt
not doubt your affertions, though I cannot ima-
gine
94
On the Succeffion of
}
gine as a fact what appears fo inconfiftent with
the evidence of reaſon.
Ment. This feeming paradox is produced by
the days being fhörtér at that period and the
Sun's rays falling in a very oblique direction on
the Earth, which are more diffuſed than they
are in Summer when he remains longer above
the horizon, and by being higher, tranſmits his
rays in a more diftinct manner, by which means
the Earth acquires and retains fo great a por-
tion of heat that it cannot be fubdued or ex-
tinquifhed during the fpace of a ſhort night,
which is occafioned by the Sun being more
nearly in a vertical pofition, and his beams.
confequently of a denfer or thicker quality
and not fo much weakened by refraction as
when they are emitted in a more indirect courfe
as they are in Winter.
}
Lady. M. I cannot comprehend how this
can be proved.
Ment. By obfervations on the Sun's diame-
ter, which it has been demonſtrated is on the
ſhorteſt day 32 deg. 48 min. and on the long-
eſt day 31 deg. 3c min. which aſcertains be-
yond the poffibility of a doubt, the proportion
of proximity with refpect to the Earth.
Lady
}
Day and Night, c.
95
1
Lady L.
What portion of the Globe is
fuppoſed to feel the heat of the Sun in the great-
eſt degree?
4
Ment. When the Earth is nearest to the
Sun, it is Summer in the Southern Hemiſphere;
therefore it is reaſonable to imagine, the inhabi-
tants of thoſe regions experience a greater degree
of heat, than thoſe which are ſituated in the
fame degree of latitude in the oppoſite Hemif-
phere; to counterbalance this circumftance,
their Summer is fhorter than ours, by the ſpace
of eight days; it is alfo colder near the Poles
in the Southern, than the Northern Hemif-
phere, which is occafioned by there being more
land, which naturally retains the heat, whilſt
on the contrary the intenfe cold near both
the Poles, in a great meaſure proceeds from
the fields of ice in the Ocean, which even the
rays of the Sun, in Summer do not wholly dif-
folve, by the moſt powerful influence of their
genial heat.
Lady M. I feem better acquainted with the
Zones, than moſt parts of your inſtructions on
Aftronomy.
:
Ment. This knowledge you have acquired
in your geographical leffons, and I make no
doubt that you recollect the Globe is divided
into
96
On the Succeffion of
into five Zones, or Belts, one Torrid, two
Temperate, and two Frigid, appellations which
clearly denote their refpective qualities. The
Equator divides the Globe into two Hemif-
pheres or equal parts, the one Northern and
the other Southern; on this circle the degrees.
of Longitude are marked, by which you are to
underſtand the diftance of any particular place,
Eaft or Weft, from the meridional point afcer-
tained on that map or Globe, which cannot in
any instance exceed 180 degrees. The meri-
dian divides the Globe into two Hemiſpheres,
Eaſtern and Western, on which the degrees of
Latitude are placed; by thefe the diſtance of
any place is found North or South from the E-
quator, and as there are 90 degrees from the
Equator to each Pole, no place can exceed that
number, as you will remember the circumfe-
rence of the Globe is 360 degrees. The Eclip-
tic is a certain line that runs through the Zodiac,
to fhew the Sun's annual path in the Heavens,
on which are marked thoſe Conſtellations, cal-
led the Signs of the Zodiac...
Lady M.
·
When I confider the different
pleaſures we enjoy in every Seafon, I know-not
which to prefer.
Ment.
Day and Night, &c.
97
Ment. The ſeaſons all abound with ſources
of delight and admiration. In Spring we be-
hold the works of Nature unfold by gradual de-
grees, till they attain the higheſt perfection of
beauty. Vegetation, the Animal world, and
the general face of things, infpire a contem
plative mind with thofe lively fenfations that
afford a kind of rational banquet, where the eye
is regaled with varied excellence, the ear charm-
ed with melody, and the intellectual powers
kept in perpetual purſuit, by the inveſtigation
of the progreffive renovating changes peculiarly
appropriate to this feaſon. Spring with pro-
priety may be faid to be the youth of the year,
in which bloom is but the harbinger of the
more mature perfection which Summer pre-
fents; buds and bloffoms become fruits and
flowers, and the pleafing expectations formed
from vernal fructification, are realized; this
luxuriant period may be ftyled Nature's Meridi-
an, as the Earth at this feafon is at the height
of its fplendor, Vegetation in the zenith of its
glory, and every furrounding object cheered by
the vivid rays of the Sun, which diffuſe the
bleffings of plenty, adorned by refplendent beau-
ty. In Autumn we perceive the ample provi-
fion which is wifely ordained for the preferva-
F
tion
98
On the Succeffion of
tion and fuftenance of every fpecies of animals,
as Nature at this ſeaſon pours forth her richeſt
gifts with a liberal hand in the various means
The furniſhes for our fupport and happineſs.
Winter, which appears at the first view to be a
dreary comfortleſs feafon, ferves the purpoſe of
a kind of repoſe to all the varied works of the
Creation, and produces that variety and con-
traft which conſtitutes in a combined fenſe the
genuine beauty of the ſeaſons, or rather mani-
fefts the infinite wifdom of their omnifcient
Creator. In froft, fnow, or hail, we may
trace certain degrees of beauty and utility, and
perceive the beneficial purpoſes for which they
were defigned; as the rigour of Winter deſtroys
the pernicious effects which would ariſe from
the exuberance of infects and reptiles that are
generated in Summer, and fertilizes the Earth
for the approaching productions of Spring:
therefore the whole year, as taken in the aggre-
gate, may be regarded as a circle of varied ex-
cellence.
Lady L. I never before formed any idea,
that each ſeaſon abounded with ſo many advan-
tages, as you have enumerated.
Ment. The change of Seafons produces in
general no other fenfations in the minds of
common
Day and Night, c.
99
common obfervers, than the habitual ideas that
occur, reſpecting the change of reſidence and
fituation which they often produce; thus for in-
ftance, many prefer Winter, as at that period
they visit the metropolis, and are engaged in a
conftant fucceffion of diffipation and luxurious.
purſuits whilft others dread its approach, be-
cauſe they live in retired fituations, and are in
fome degree debarred from focial intercourfe.
:
Lady M. I think there is no degree of com-
pariſon reſpecting the preference which ought
to be given to the fituations you have defcribed:
I fhall not heſitate to determine in favor of
Winter, as at that ſeaſon I ſee the moſt com-
pany.
Ment. Society is the balm of life, and ra-
tional modes of amufement may be enjoyed
without deviation from our preſcribed line of
duty; yet how frequently do the purfuits of
what is delufively called pleafure, produce the
contrary effects of difquietude and repentance.
Each feafon points out to the intelligent mind.
a certain mode of comfort, peculiarly adapted to
its circumſtances and quality; fuch as in Win-
ter, a cheerful fire, focial converfe, innocent
recreations, confifting of thoſe which can occa-
fion no perturbation of mind, or juſt cauſe of
blame
F 2
700
养
​On the Succeffion of
#
blame or regret. Conftant employment is the
grand ſpecific against what the French call en-
nui; but we muſt be ever cautious, that the uſe
of our time ſhould be turned to ſuch objects, as
may produce individual advantage, or public be-
.nefit.
Lady M. I obferve you mention that our
amufements ſhould be of a nature to produce
no uneafineſs or unpleafant confequence; I
think there is no danger they ever ſhould.
Ment. Of this there is greater probability
than you are aware; as the purſuit of diverſion
frequently induces perfons to engage in ſchemes,
or enter into plans that are inadequate to their
finances, or incompatible with the arrangement
their fituation in life requires; games of chance
alſo, or thoſe that depend on any degree of fkill,
engage young minds with too great a degree of
ardour and anxiety; therefore the object to be
won, or loft, ſhould always be of trifling value,
as both parties cannot be fucceſsful; and though
the victor experiences fenfations of triumphant
pleaſure, the vanquished or perfons conquered,
are fubjected to an equal portion of regret.
Lady L. I must confefs that I am always
pleaſed when I win, though I'do not care for
the money.
Ment.
Day and Night,·EST,
101
Ment. This is the genuine fentiment, ari4
fing from the fimplicity and uncorrupted ſtate
of your heart; but intercourfe with the world
blunts theſe fine perceptions, and the hope of
gain often degenerates into means and meaſures,
not always according with liberality or ftrict
juſtice.
Lady M. will zealouſly guard againſt the
confequences you fo forcibly deſcribe; and I
imagine you will recommend a courſe of read-
ing as our general purſuit in Winter.
}
Ment. I am rather inclined to a diverſity of
avocations, as they exercife the various faculties
of the mind; neither am I averfe to what is
finally called gaiety, when purfued as a relaxa-
tion under certain reftrictions, and regulated by
the rules which good fenfe and prudence pre-
fcribe. The theatre is a fource of, amufement
and improvement,, when the fubjects chofen for
repreſentation, are of a tendency to infpire noble
fentiments, by bright examples; or to exhibit
Vice and Folly in their proper colours. Con-
certs and mufical entertainments are not only
agreeable, and defirable, but may even be turned
to excite devout fenfations, or to exhilarate the
fancy by lively compofitions. Dancing is a
wholeſome exercife, and fource of diverfion,
7
}
F 3
and
102
On the Succeffion of
A
*
and alſo tends to add grace and dignity to the
deportment. Painting and drawing of every
fpecies, are an elegant pleaſing employ, and
when extended to taking views, or copying
from Nature, afford an inexh.uftible fund of
gratification to a mind replete with refined
ideas.
Lady L. By purfuing the plan you recom-
mend, I am convinced time will never appear
burdenfome to me, even in the depth of Win-
ter.
J
{
Ment. It is impoffible to enumerate the va-
ried objects of purſuit, as they muſt ariſe from
the circumftances that furround us. Needle
work, of the uſeful and ornamental kind, fhould
engage a portion of your time and attention, as
being more particularly a feminine employ,
and productive of utility. Exercife is alſo a
means of diſtributing time with advantage and
pleaſure, and may be compaffed even in Win-
ter, with benefit and delight. But above all
I will point out the advantages arifing from
the ſtudy of the most approved authors, and
from the converfation of intelligent, well-bred
perfons; this is not only the means of pafling
over time agreeably, but with fubftantial pro-
fit; as knowledge is not only confined to books,
but
Day and Night, k3c..
103
but may be diffufed by various other means;
amongſt which, none are more forcible than
the admonitions, teftimonies, or opinions of
thoſe we defervedly revere or esteem.
$
Lady M. I am perfectly fatisfied with our
allotment in Winter; pray, Mentoria, point
out of what nature our employ fhould be in
Summer.
Ment. In fpeaking of our purſuits in diffe-
rent times of the year, we ufe the general terin
of Summer and Winter, with which ve blend
Spring and Autumn, and confine ourselves fin-
ply to the diſtinction of heat or cold, long or
fhort days. In Summer every object takes a
wide range; the great portion of day-light we
enjoy, and the genial warmth of the Seaſon,
confpire to difperfe the generality of perfons
who can purſue their own inclinations. In the
higher claffes, the greater part retire from the
buſtle of public or ſplendid life, and take refuge
in the calm retreat of their patrimonial man-
fions. Others in purfuit of health, or amufe-
ment, frequent places on the fea coaft; whilſt
the general mafs, who are engaged in com-
merce and uſeful avocations, content them-
felves with occafional excurfions, which can
F 4
{
be
104
On the Succeffion of
be purfued without material-interruption to the
regular courſe of their bufinefs.
*
Lady L. I am always impatient to get into
the country, and if it were in my power to
chuſe, fhould like fome cottage, or rural ſpot,
where I fhould be more happy than I can ex-
prefs.
Ment. Thefe ideas are the effect of a youthful
imagination, which is apt to figure to itſelf that
wild, or romantic fcenes would yield a fuperior
degree of fatisfaction; when in fact they would,
when the edge of novelty was worn off, pro-
duce vacuity and diſguſt. It is impoffible to
define by what meaſures happineſs may be
moft effectually produced; as much depends on
the turn of mind, and the fituation of the par-
ties concerned; yet we may fafely venture to
affirm, there is the best chance for attaining
this defired end, by active, rather than abſtract-
ed means. A cottage allows but a ſmall ſphere
of action, a paftoral life admits but of few va-
riations, the habits are fimple, and by conſtant-
ly preferving the fame uniform tenor, enervate,
and cramp a mind inherently fraught with laud-
able curiofity.
Lady M
Day and Night, &c.
·105
4
Lady M.
I have no doubt you would ap-
prove the plan of life purfued by our amiable
friends Horatio and Amanda.
Ment. Diftinguithed merit like theirs claims
approbation and applaufe. Their rank in life
is high enough to fupply them liberally with
all that can be ſtyled the bleffings of life; and
yet not fufficiently elevated, to involve them in
the pernicious and difgraceful habitudes, that
degrade too many who fill the first claffes in fo-
ciety. In fummer they refide at their country
feat, in which elegance and convenience unite,
their grounds are highly cultivated, their gar-
dens are a Botanical fchool; agriculture alfo
bears a ſhare in this beautiful arrangement, as
the whole eſtate is a Ferme Ornée.. Horatio is
a man of ſcience, and neglects no opportunity
to adopt every plan that may prove beneficial to
fociety; his flocks and herds are of the fineſt qua-
lity, his horfes of the beſt breed, and regularly
trained, and his carriages of the most elegant.
and convenient conftruction.
Lady M. How happy Amanda muſt be in.
fuch a fituation!
Ment. In thoſe branches which come im--
mediately under her department, every article
approaches nearly to perfection. Her aviary
F 5.
and:
105
On the Succeffion of
and poultry, form an affemblage of the most
rare and beautiful kinds of fowls and birds; her
fhrubbery and green-houſe abound with the
moft curious plants, which fhe ftudies with the
moft minute attention, and by the moft fcien-
tific rules. Her houfe difplays the purity of her
tafte, the furniture being in the flyle of the
moſt elegant fimplicity, and many of the deco-
rations moſt worthy of applaufe, executed by
her own hand. In the whole of this rational
fyftem you perceive neither redundancy nor de-
fect, and the moſt ſtriking harmony is produced
by judicious meaſures, effected by moderate
means of expence. Horatio's and Amanda's
method of living, is hofpitable and liberal; but
as it is uniform, kept within due bounds of pru-
dent œconomy, by which mode they perform
many ſignal acts of charity, though their for-
tune is far from being immenſe.
Lady E. I am always extremely happy when
I pay them a vifit; there is a library well ftor-
ed with books, mathematical inftruments of all
kinds, and every thing that is curious or inge-
nious.
Ment. Thefe are rational fources of amuſe-
ment, and when properly recurred to, produce
the happieſt effects. Society forms a great part
of
Day and Night, &c.
107
of the comforts of this amiable pair, it confifts
of all the beſt families in the neighbourhood, by
which I mean thoſe moſt reſpectable, not al-
ways thoſe of the higheſt rank; as Horatio does
not approve Lord Sceptic's principles, or Sir
Richard Squander's profufe habits: neither does
Amanda wiſh to affociate, with diffipated Lady
Random, nor contemptible Lady Sordid. The
time and attention of thefe worthy members of
fociety are greatly engaged by the education of
their children; as they do not confine their in-
ftructions merely to the hours allotted for their
leffons, but are always inculcating ſome impor--
tant branches of knowledge from every occur-
rence, and correcting all the errors they per-
ceive, by the moſt forcible, yet gentle means.
Lady L. Horatio and Amanda are very kind
to their fervants, and poor neighbours, eſpeci-·
ally when they are fick; and have alfo eftab-
lifhed a ſchool for indigent children, who are
inftructed and clothed at their expence.
Ment. The performance of thefe effential
duties, are the luxuries which I wa
merd, as they never cloy; every evil you
gate 13 an exquifite gratificarne, o alt
the pains of fickneſs, remove the Chann
verty, or plant the feeds of knowledge to
F 6
3ppli
?
108 On the Succeffion of Day and Night.
application of due remedies and pecuniary re-
lief, places a human character in the brighteſt
point of view: thus you perceive Horatio and
Amanda in their Summer refidence ſhed a bleſ-
fing on all who are within the fphere of their
cheering influence. As the means of converting
their bright example to your individual benefit,
I fhall obferve, that notwithstanding you cannot
wholly adopt their plan, let it impart this ufe-
ful leffon, that virtue confifts in active exer-
tions, and that each ſeaſon of the year calls us
forth to fulfil fome important duty; as even the
moſt minute object teems with inſtruction, and
every diſpenſation demands the grateful tribute
of reverence and admiration!
DIALOGUE
}
+
DIALOGUE V.
Y
FRIDA Y
F
On Eclipfes and Tides.
5 127
Mentoria.
HE obfervations I have made on the vari-
THE
ous qualities of the Solar Syſtem would be
incomplete, unleſs I were to enumerate the
diftinct properties of Eclipfes of the Sun and
Moon, which you have ſeen and heard of, but
I fear, are ignorant of their natural caufes. A
Solar Eclipfe is produced by the Moon paſſing
between the Earth and the Sun, which hides
the light of the Sun from the Earth; this muſt
happen at the New Moon, when the Moon is
in conjunction with the Sun. It is called an
annular
IIO
On Eclipfes and Tides.
annular Eclipfe, when the Moon is ſo ſituated
that its fhadow being lefs than the diſk of the
Sun, conceals only the centre from our view;
the edge of the Sun appearing to ſurround it
like a bright ring. If the whole of the Sun is
obfcured, the Eclipfe is termed total; but if
only a part is darkened, it is called a partial
Eclipfe, and as many twelfth parts as the Moon
covers, fo many digits are faid to be eclipfed.
Lady Louifa. What do you mean by digits?
Ment. The term digit, fignifies the twelfth
part of the diameter of either the Sun, or Moon,
therefore is uſed to exprefs the degree, in which
either are occulted, or darkened. No folar
Eclipfes are univerfally feen throughout the
whole hemifphere, which is occafioned by the
Sun being then above it, the Moon's diſk or
face being too fmall, and too near the Earth,
to hide the Sun from its difk. Ufually the
Moon's dark ſhadow covers only a ſpace on the
Earth's furface about 180 miles broad, when
the Sun is at the greateft, and the Moon at
the leaſt diſtance; though her partial ſhadow,
or penumbra may at that period, cover a cir-
cular portion of 4900 miles in diameter with-
in this fpace, the Sun is in a greater, or leſs
degree
}
On Eclipfes and Tides.
III
degree eclipfed; as the places are near, or dif-
tant from the centre of the penumbra.
Lady Mary. What is the fignification of
the word penumbra?
་
Ment. It implies a faint kind of ſhadow,
on the extremity of the perfect, or complete
fhadow, which renders it difficult to deter-
mine where the fhadow begins, or ends. By
the obſervations I have made, I hope you clear-
ly underſtand that Eclipfes are a privation of
light, which the inhabitants of the Earth derive
from the Sun, or Moon. It moſt frequently
happens in folar Eclipfes, that the Moon's difk
is covered with a faint light, which is aſcribed
to the reflection of the light from the illumi-
nated parts of the Earth; in total Eclipfes of
the Sun, what is called the Moon's limb, (by
which is meant the exterior border of her diſk)
appears furrounded by a pale circle of light,
that fome aſtronomers imagine indicates a lunar
atmoſphere of the Sun. When the Moon ap-
pears much leſs than the Sun, ſhe is ſaid to be
in apage, and he in perige; the former term
implies the greateſt poffible diſtance, the latter
the neareſt fituation any Planet is removed from
us. The total occultation of the Sun can never
exceed four minutes, and more commonly not
more
112
On Eclipfes and Tides.
more than two minutes, though at ſome particular
place on the Earth an Eclipfe may laſt for more
than two hours. A Solar Eclipfe does not happen
at the fame time in all places where it is feen;
but is vifible earlieſt in the Weſtern parts, and
later to the Eaftern region, occafioned by the
fhadow of the Moon, as her motion is from
Weſt to Eaſt.
Lady L. I with very much to hear what
occaſions a Lunar Eclipſe.
-Ment. An Eclipfe of the Moon is produce
ed by the Earth paffing between the Sun and
the Moon, in confequence of which, the latter
is deprived of the folar light; this only happens
at the full Moon, as at that period fhe is oppo-
fite to the Sun; even in a total Eclipfe, the
Moon is feldom in a perfect ſtate of occultation,
or darkneſs; which is occafioned by the Sun's
rays being refracted in paffing through the at-
mofphere of the Earth.
Lady M. What is the cauſe the Sun is not:
eclipfed every New Moon, and the Moon:
every time ſhe is at the full ?
-
-Ment. Becauſe the Moon's orbit is inclined
to the plane of the Ecliptic, therefore an Eclipfe
can never happen but when the Moon is either
in or near one of the Nodes, which are the
two
On Eclipfes and Tides.
113
two points in which the orbit of the Moon
cuts the Ecliptic.
Lady L. Do Eclipfes appear in every part
of the Globe?
Ment.
A Lunar Eclipfe is vifible in all parts
of the Earth, which have the Moon above their
horizon, and are every where of the fame ex
tent and duration; whilſt a folar Eclipfe varies
its appearance at different places. Eclipfes of
the Moon always begin on her eaſtern fide,
whilft thofe of the Sun commence on his weſt.
ern.
Lady L. How many Eclipfes of the Sun
and Moon can there poffibly be in one year ?
Ment. Seven are the greateſt number that
can happen in that space of time, and two the
leaſt that can occur ; the moſt uſual number is
four, and there are very rarely more than fix,
one half of which are generally inviſible at any
particular place; and no Eclipfe of the Moon
can laſt above 5 hours and a half from the pe-
riod of the Moon's first touching the Earth's
penumbra, to its departure from; it; but an
Eclipfe of the Moon by the Earth's thadow
probably never exceeds 3 hours and three quar-
ters, and when total, is not more than I
hour and three quarters. Having thus clearly
Specified
114
On Eclipfes and Tides.
$
ſpecified the interpofition of the heavenly bo
dies which occafion the privation of light, called
Eclipfes, it only remains. for me to remark, that
fome of the fixed ſtars are ſubject to the fame
conſequences; in particular Aldebaran is fre
quently obfcured by the Moon, when it is be-
hind that Planet, and Jupiter alfo is in like
manner darkened by its brightnefs being inter-
cepted.
Lady M. I think Eclipfes are very extraor-
dinary things; before their caufes were known,
I fhould fuppofe the inhabitants of the Earth
were alarmed at their appearance.
Ment. To have the Sun obfcured, or the
light of the Moon withheld, for even the fhort-
eft fpace of time, must have excited much af
toniſhment; but experience in this, as well as
in a variety of other inftances, fupplied the de-
fect of ſcience. The ancients obferved theſe
phænomena; But as they perceived no bad ef-
fects, most probably were not apprehenfive
when they appeared. I recollect a remarkable
inftance of the fagacious ufe that Columbus.
made of the circumftance of knowing from his
profeffional ſkill, that an Eclipſe muſt at a cer-
tain period occur, which ſerves to thew the ve-
ry great advantages the learned have over the ig-
norant
On Eclipfes and Tides.
115
norant and uninformed part of the community.
Lady M. I am greatly obliged to you my
dear Mentoria; I remember in your inftruc-
tions on Geography, you informed us Colum-
bus difcovered America.
譬
​Ment. In the proſecution of that great un-
dertaking, Columbus experienced much trou-
ble from the factious fpirit of the officers and
men who engaged with him in that hazardous
enterprize. At one time a ferious mutiny took
place, and as Columbus was at that period but
a little diſtance from land, near one of the
Weft India Iſlands, he obtained articles of fuf-
tenance of every kind from the Indians, his
own provifions having been either confumed ör
fpoiled. For fome time he was amply ſupplied
by the natives, who bartered their food for the
alluring bait of a bit of tin, or a few glaſs beads,
and on thoſe who were of a fuperior clafs, he
beſtowed a ſmall looking-glafs, a red cap, or a
pair of fciffors. This traffic was carried on to
the mutual fstisfaction of both parties, but un-
fortunately the mutineers who were on fhore,
prejudiced the Indians against Columbus, and
as in thoſe uncivilized countries they cultivate
little more than is neceffary for their own ufe,
they began to be apprehenfive of experiencing
a fear-
116
On Eckpfes and Fides.
a ſcarcity; therefore were very remifs in their
fupply of food, which greatly diftreffed Colum-
bus, as his men had been grievously afflicted
with ſevere and dangerous diſorders, which are
peculiarly incident to hot climates; a circum-
ſtance that rendered freſh provifions abfolutely
neceffary, as the moſt effectual means of eſtab-
lifhing their health. In this critical predica-
ment, Columbus had recourfe to the follow-
ing expedient. From aftronomical obſerva-
tions, he knew that in the courſe of three days
there would be an Eclipfe of the Moon; he
therefore ſent an Indian on fhore, who was
on board his fhip, to inform the inhabitants
(whom he convened) that he came to acquaint
them of an extraordinary circumſtance, in which
they were all nearly concerned. That Columbus
and his people were Chriftians, and believed in
God, who created Heaven and Earth, reward-
ed the righteous, and punished the wicked;
that this omnipotent Being was incenfed againſt
the Indians for having neglected to fupply his
people with food, and had determined to pu-
nish them by peftilence and famine, in token
of which, they would that very night fee the
Moon rife with an angry and bloody aſpect, as
a prefage of the tremendous evils that would ac
crue..
On Eclipfes and Tides.
117
}
crue. This prophetic denunciation produced
different effects upon the minds of the Indians,
fome were alarmed, and others treated it with
contempt and derifion; but when they perceiv-
ed the Eclipſe of the Moon, which took place
in the manner exprefsly foretold, they were
unanimous in expreffing their confternation and
contrition. The confequence of this internal
conviction was productive of the happieſt ef-
fects as they zealously entreated Columbus,
with loud cries and lamentations, to intercede
with his God on their behalf, as the means of
averting the fcourge that threatened them; on
which terms they promiſed in future to ſupply
him amply with every kind of provifion he re-
quired. Columbus hearkened to their entrea-
ties, yet did not grant their requeſt till the
Eclipfe began to go off; when after due delibe-
ration, and the appearance of great condefcen-
fion on his part, he informed them, they might
ceaſe to afflict themſelves, as he had prayed to
God in their favour, who had graciouſly for-
given them, on condition they would always be
kind and hoſpitable to Chriftians, and in proof
of this gracious pardon, they would perceive the
Moon difperfe her angry countenance, and re-
fume her former beauty. When they experi
༣
enced
118
On Eclipfes and Tides.
enced the fulfilment of this pleaſing affurance,
they praiſed the God of the Chriftians, and re-
garded Columbus, as a perfon peculiarly favour-
ed by heaven; as notwithstanding they had
feen Eclipfes, it was beyond the compaſs of
their comprehenfion, to imagine that any one.
could foretel their appearance, except by divine
inſpiration.
Lady L. It was fortunate Columbus thought
of ſuch a means to prevent the evils he dread-
ed; but was it ſtrictly right, that he pretended
this natural event was a divine judgment?
Ment. Particular circumſtances, and exi-
gent cafes, require extraordinary means of re-
drefs; and in this inftance, on the behalf of C»-
lumbus, I fhall urge that the happy effects his
conduct produced, in a great meaſure plead his
excuſe, more eſpecially as it ferved the benefi-
cial purpoſe of forcibly impreffing on theſe fa-
vage Indians an awful idea of the Supreme Be-
ing, which perhaps they would not have acquir
ed by any other means. In defining the cha-
racter of Columbus, we muſt acknowledge he
poffeffed very ſuperior merit; his fkill in naviga-
tion was wonderful at that period, his genius
enterprizing, and his prefence of mind fignal,
in
On Eclipfes and Tides.
119
in all the complicated misfortunes his arduous
undertaking unavoidably produced.
Lady M. What do you mean by preſence
of mind, my dear Mentoria?
Ment. That powerful impulfe, which di-
rects us to pursue in any emergency, thofe mea-
fures that will prove effectual; as perfons in-
volved in intricate and apparently inextricable
difficulties, if they were to deliberate, would be
loft!
Lady L. I think it was very ungrateful of
Columbus's officers and men to fhew any incli-
nation to rebel, under fo great a coinmander.
Ment. In enterprizes of vaft importance,
the projectors have many adverſe events to con-
tend with. The greater part of the perfons
who joined Columbus in the profecution of the
expedition he had planned, were actuated by
motives of gain, and were impatient under the
delay, which in the natural course of things re-
tarded the object they had in view; confequent-
ly the principal obſtacles he had to encounter,
arofe from the avarice, ingratitude, and igno-
rance of his fellow labourers: thus you will per-
ceive the paffions were to him more turbulent in
their effects, than the Elements. Human nature
is the fame in every age and nation, the children
of
120
On Eclipfes and Tides.
of Ifrael murmured againſt Mofes for the dan-
gers and inconvenience they experienced in the.
defert, in their progrefs to the Land of Promife;
and reproached their wife benign leader, with
being, the cauſe of all their ſufferings.
Lady L. It must have given Columbus
great pleaſure, to have the Indians pay him
fuch reverence.
Ment. In a variety of inftances, recorded
in hiftory, we find that the human race, in a
ſtate of profound ignorance, are eaſily wrought
upon by any circumſtances which bear a ſuper-
natural appearance; this gave rife to the abfurd,
and I may add impious. ftories, which were im-
preffed on the multitude in the firſt ages of the
world in Pagan countries; as under the fanc--
tion of a pretended divine origin, no one pre-
fumed to doubt the validity of any affertion or
event. Numa, who governed the Romans af-
ter Romulus, was a man of confummate wif-
dom and prudence; and as he was convinced
he could not rule peaceably over his fubjects,
without fome fuperior aid, he pretended to
have an intercourfe with the Goddefs Egeria,
whom he apparently confulted in her grotto, on
all fubjects and matters of importance; thus by
impoſing on the minds of his fubjects this
feigned
$
On Eclipfes and Tides.
12-1
feigned. facred authority, he poffeffed their en-
tire confidence, and much to his honour it may
be added, that he was the first who inſpired
the Romans with an awful fenfe of the facred
obligation of an oath, which was undoubtedly
the foundation of the credit they afterwards ob-
tained; as it rendered them juft and honourable
in all their proceedings.
Lady L. I am much pleaſed with the in-
ſtances you have produced of the fuperior abili-
ties that Numa and Columbus poſſeſſed.
Ment. As I have endeavoured to fhew you,
the advantage perfons inveſted with power derive
from the adoption of wife and prudent meaſures,
the refult of a highly cultivated good underftand-
ing; as a contraft, I will now point out the
contrary effects, by the example of Francis Pi-
zarro, who obtained the conqueft of Peru.
Various have been the conjc&tures refpecting
his origin, fome are of opinion he was a no-
bleman by birth, whilst others (with greater
probability) mention, he was the illegitimate-
fon of Gonzalo Pizarro, an officer of Truxillo
in Spain, who expofed him as a foundling at
the door of a church; from the circumſtance
of the cheat being difcovered, his father was
compelled to fupport him, who bestowed no
G
educa-
12:2
On Eclipfes and Tides.
↓
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education on him, but employed him in the
moſt ſervile offices, chiefly in tending his hogs;
as this neglected youth advanced in age, he grew
weary of this degrading courſe of life, and as
he was of an enterprifing fpirit, entered on
board a fhip bound for the Weft Indies. In
this new fcene of action, Pizarro fo eminently
diftinguiſhed himſelf by his bravery, in the wars
of Hifpaniola and Cuba, that he gained a com-
miffion in the Spanish army; after a variety of
fortunate events, he became poffeffed of great
riches, and joined with two other adventurers,
to undertake the conqueft of Peru, in which
hazardous attempt he fucceeded.
Lady L. I feel quite intereſted in your ac-
´count of Pizarro, and am furpriſed a perſon fo
'defective in education fhould achieve. fuch a
brilliant victory.
Ment. Perfonal courage, perfeverance, and
concurring favourable circumſtances, are more
effectual in compalling great deſigns, than mere
intellectual poffeffions, or the genuine effects of
regular fcience; yet when they are added to
the other qualities they give an inexpreſſible de-
gree of confequence to the triumphant Hero:
which was manifeſt in the character of Julius
Cæfar, who was an excellent fcholar, a
gallant
•
On Eclipfes and Tides.
123
gallant foldier, and in every department, a moſt
accompliſhed man.
$
1
Lady M. Pray Mentoria, now inform us
of fome ſtriking proofs of Pizarro's ignorance?
Ment. At the time the conqueft of Peru
was undertaken, there was a contest between
two brothers, named Huefcar and Atabiliba,
for the fucceffion to the Peruvian dominions, on
the death of their father. This event proved
fortunate for Pizarro, who by artfully feeming
to eſpouſe the cauſe of both thefe incas, or prin-
ces, who were competitors, at length by ſtrata-
gem, and a kind of fictitious cauſe of offence,
Pizarro impriſoned Atabiliba, and very foon
after Huefcar was murdered, which in a great
meaſure ſecured the victory that was afterwards
obtained. Atabiliba was a prince endued with
great penetration, and as he earnestly wished to
procure his liberty, fought to difcover the man-
ners, abilities, and cuftoms of the Spaniards,
as the beſt method of enabling him to offer for
his ranfom thofe gifts that would be the moſt
acceptable to them. What appeared the moft
incomprehenfible to him, was, their being able
to read and write, which he was at a lofs to de-
termine, whether they were natural gifts, or
acquired by application and labour.
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As the
micaus
124
On Eclipfes and Tides.
means of obtaining this information, he afked
one of the Spanifh foldiers, if he could write.
the name of God upon his thumb nail; the
man immediately complied with his requeft;
and the inca went to feveral of the Spaniſh cap-
tains and foldiers, to enquire of them the figni-
fication of the word infcribed on his thumb,
and by their reply was convinced they under-
ftood its meaning, from which he concluded
that the art of writing and reading were natural
to the whole Spanish nation. This opinion he
was fo in convinced was erroneous, as by chance
he met Pizarro, and aſked him the fame quef-
tion refpecting the mark on his nail, which the
other Spaniards had fo readily interpreted; when
he from the conſciouſneſs of not being able to
write or read, blufhed and turned away from
him with evident figns of confufion, from not
being qualified to give a fatisfactory anfwer.
This circumftance convinced Atabiliba, that the
accomplishments he fo greatly admired were.
the effect of fuperior education, and infpired
him with contempt for Pizarro, whom he now
perceived was of a very low origin, fince he
was exceeded in knowledge by even foldiers of
the moſt inferior rank.
Lady
On Eclipfes and Tides.
125
Lady M. I am aſtoniſhed that Pizarro did
not learn to read and write when he was a great
man, as it is very difgraceful to be fo igno-
rant.
Ment. Knowledge is very difficult to at-
tain, except in the ductile feafons of infancy
or youth; the procefs of acquiring it is flow
and progreſſive, and muſt be purſued without
intermiffion, which, when perfons are advanced
to the mature ſtages of life, is not eaſy to ef
fect; as a variety of avocations at that period
unavoidably engage their attention. Pizarro's
time was I make no doubt wholly employed in the
purfuit of riches and power, which he obtained
to the full extent of the moſt fanguine ambi-
tion: but to counterbalance theſe advantages
he was fubjected to the humiliating mortifica-
tion of his fecretary writing his name as a fig-
nature, between two ftrokes which Pizarro
drew, a circumſtance that made his ignorance
univerſally known.
Lady M. When perfons are fo high in
rank, it is particularly unfortunate when they
are fo illiterate.
Ment. In commercial countries, it frequent-
ly happens that individuals of low birth, by ha-.
bits of induſtry, perfeverance, or enterprize,
G 3
attain
326
On Eclipfes and Tides.
attain in the regular courſe of things, great
riches, and confequently a proportionable de-
gree of power and confequence. When fuch
perfons. by the influence of their wealth and
connections, becomè fenators, or affociate with
the higher circles, they betray their own infuf-
ficiency in what the liberal minded eſteem the
moft valuable poffeffions; as their language is
incorrect, and their opinions generally con-
traced and ill founded: thus you will perceive
the inefficacy of riches, which may purchaſe
parade, and flate, but cannot deſerve the tri-
bute of applaufe or admiration, unless they are
accompanied by intrinfic and fuperior worth.
J
Lady L. I recollect that Tides are the next
fubject of your inftructions; I have fome know-
ledge of them, as I spent part of laſt Sum-
mer in a beautiful ſituation on the ſea coaſt.
}
Ment. The Tides are produced by the At-
traction of the Sun and Moon, and are caufed
by the flux and reflux of the motion of the vatt
expanfe of the ocean, which is in a perpetual
ftate of agitation, as it ebbs and flows alter-
nately, without intermiffion. This wonderful
effect is more particularly occafioned by the
Moon, in conféquence of her being much near-
er to the Earth than the Sun, therefore her
powers
On Eclipfes and Tides.
127
powers of attraction, though inferior, act with
greater force, and as a natural confequence,
raiſe the water much higher, which from being,
a fluid, lofes in a great meaſure its gravitating.
property.
1.
!
Lady L. How furprising thefe circumftan-
ces are, and how very few. I imagine have a
knowledge of their wonderful effects..
Ment. The Moon in paffing over any part
of the ocean, attracts and raiſes the water in
that particular place, which in the courfe of
about fix hours and eleven minutes falls again,
and thus invariably rifes and falls in little more
than the ſpace of twelve hours. The Moon
produces the effect of raising the water, not
only on that part of the fea over which he is
paffing, but alfo on that which is fituated in
an immediate oppofite direction. The effects
that the Moon occafions on the water are not
perceived till three hours after it has paffed the
meridian of that place.
Lady L. I imagine the Tides, perform their
changes with equal uniformity in all parts of
the ocean.
Ment. The remarks I have made, more par-
ticularly belong to fuch fituations as are open to.
large oceans; as in feas and channels that are
1
G 4
*
more
128
On Eclipfes and Tides.
more confined, many circumftances concur to caufe
deviations from the rules I have ſpecified; the
effects would be general, if the whole furface.
of the globe were covered with water; but the
great number of iflands and continents inter-
rupt the regular courfe of Tides in fome parti-
cular regions.
Lady M. I know that rivers have Tides as
well as the ocean, as I have obferved them re-
gularly change, when I was at Greenwich.
Ment. All rivers which fall into the fea have
a flux and reflux, at ſome diſtance from their
mouth. I have already explained why the
Moon attracts the ocean in a greater degree
than the Sun, the proportion of the attractive
powers of the latter, with respect to the Tides,
is computed to be four times and a half leſs.
than what is produced by the Lunar influence,
which effect is caufed by the great diſtance of
the Sun from the Earth; I ſhall now endeavour
to fhew you, in what degree the Tides are af-
fected by the concurrent addition of the Sun's
force of Attraction. At the time of the new
and full Moon, the Sun and Moon, by acting
together on the water, raife it to a more confi-
derable height: thefe elevations are called the
Spring Tides; at the firſt and laſt quarters of
the
On Eclipfes and Tides.
129
T
1
the Moon, the Sun and Moon act in oppofition
to each other, and the water in confequence,
does not rife ſo high as under the operation of
their mutual attraction: thefe are called Neap
Tides.
Lady L. Are not the Tides later every day
for a certain ſpace of time?
Ment. Undoubtedly, as the Earth is re-
volving on its axis 24 hours, the Moon will be
advancing in her orbit; therefore the Earth muſt
turn as much more than round its axis, before.
the fame place, which was under her, can
come to the fame place again with reſpect
to her, as he has advanced in her orbit;
during that ſpace of time, which is 50 minutes,
this number being divided by 4, gives 12 mi-
nutes and a half; fo that it will be 6 hours,
12 minutes and a half from high to low water,
and the fame portion of time from low to high
water again, which make in the whole 12
hours, 25 minutes, from the period of high wa-
ter to its regular return.
Lady L. The Tides I fuppofe are of great
ufe, as I have obferved when I have been near
the fea, or River Thames, how many veffels
pafs in conftant fucceffion."
Ment,
1:30
On Eclipfes and Tides.
Ment. Important and numerous are the be-
nefits we derive from the regularity of the Tides.
Water in a ſtagnate ſtate becomes foul, and de-
generates into putridity, which is productive of
the moft baneful and fatal effects; as the efflu-
via that arifes from it, by its noxious qualities.
corrupts the air, and confequently produces pef-
tilential difeafes. Another effential advantage
from the flux and reflux of the Tides, is the
means they afford for a wide extended com-
merce; as by their variations, veffels of all def-
criptions and dimenfions can proceed from the
ocean to the centre of the metropolis, by which
channel commodities from all parts of the globe
are collected in the great emporium of trade,
and from thence diffuſed by different meaſures,
not only for the general accommodation of this
kingdom, but alſo for the ſupply of foreign
I fhall conclude this differtation on
Tides, by obferving, that the doctrine refpect-
ing them was involved in obfcurity, till Sir
Ifaac Newton removed thefe doubts and myſ-
teries by the clear demonftration of the power of
Gravity and Attraction.
marts.
Lady L. Pray Mentoria, explain this mat-
ter more fully, as I have a general but not a
clear idea of its properties; particularly I wiſh
to
On Eclipfes and Tides.
£31
to be informed what the term Gravitation.
means.
Ment. It fignifies the tendency which all
bodies have to defcend, and the point to which
they tend is called the centre of Gravity.
Lady L. This I comprehend, but en-
treat you will be more explicit on this ſubject.
Ment. In the Solar fyftem, the Sun is the
centre of Gravity; and the centre of the Earth,
and of all the other Planets, is a centre of gra-
vity towards which all bodies placed upon their.
furface are attracted...
Lady L. By what means are you convinced.
of this?
Ment. The Sun from, its fuperior magni-
tude attracts the Earth, and other Planetary
Orbs of its ſyſtein, which may all properly be faid
to gravitate, or have a tendency to approach the
Sun as their centre.. The Earth, by being of
larger dimenfions than the Moon, attracts her,.
and the, as a fecondary Planet, gravitates to-
wards the Earth. The Planets are attracted by
and alſo gravitate towards each other. When
a ſtone is thrown from the Earth, its weight or
gravitating power attracts it to the Earth again ;.
and by this univerfal power of Gravitation, we
ftand upon all parts of the Earth, with our feet
G 6
pointing
132
On Eclipfes and Tides.
as
pointing to the centre. The power by which
the Planets are attracted towards the Sun,
their centre, is called the Centripetal Force,
and that by which they endeavour to fly from it,
is termed the Centrifugal Force: thus by the
contrary action of thefe different powers, the
Planets are made to move round the Sun, in `a
circular, or rather in an elliptical Orbit, and it
is by the joint action of thefe oppofite forces,
that the Planets are retained in their proper Or-
bits.
Lady M. I wish to know what produces
this effect.
Ment. It may be proper to inform you that
all motion which is termed fimple, is naturally
rectilineal, that is, that all bodies, if there
were no counteracting power, would move in
ftraight lines, which might be proved in a va-
riety of familiar inftances; you will therefore
perceive, as the planetary motion is nearly cir-
cular, it cannot be called fimple, being a com-
pound of the two qualities already fpecified,
which are diſtinguiſhed by the following terms,
the Attractive or Centripetal force, and the Pro-
jectile, or Centrifugal force.
✓
Lady L. I am very attentive to theſe in-
ſtructions, as they appear to me of great con-
fequence>
On Eclipfes and Tides.
133
, ?
fequence, by enabling me to tinderſtand the
general order of the Planetary fyftein.
Ment. The attraction of the Earth and the
reſiſtance of the atmoſphere or body of air
through which it moves retards its progrefs or
it would continue to move in a ſtraight line
with a degree of velocity, equal to that which
was first impreffed on it. The wiſe Creator
of the univerſe, has bestowed a force on all
the Planets, equal to that of the attractive
power of the Sun, that one might not be over-
powered by the other; the Attractive or Cen-
tripetal force of the Sun, being adequate in
proportion to the Projectile, or Centrifugal force
of the Planets, which are by Attraction prevent-
ed from moving in a ſtraight line, being in a
manner driven towards the Sun, and by the
Projectile force are hindered from being over
come by the Attractive power, conſequently they
revolve in circular orbits, though in fact they
are rather elliptical in form. All bodies mov-
ing in a circle have a natural tendency to fly
off in a straight line did not the central force act-
ing againſt it preſerve its circular motion Be-
fore I conclude thefe remarks upon the general
law of Nature, I mull mention the remaining
branches of Magnetiſm, Electricity, and what
is
134
On Eclipfes and Tides.
is called the Attraction of Coheſion: the two-
former I thall diftinctly confider on fome fu-
ture occafion, but ſhall briefly inform you that
the latter, Attraction of Coheſion, fignifies that
property that all bodies inherently poffefs, which
tends to unite the different particles of which
they are compofed, and connects the general
fyftem; or they would, uninfluenced by theſe
Attractive powers, be hurled to immenfe dif
tances, or ſeparated into an infinitude of atoms..
Lady M. Do the rules and confequences
you have enumerated reſpecting the heavenly
bodies relate only to the primary Planets, which
have the Sun for their centre ?
Ment. The fecondary Planets are governed
by the ſame laws, in revolving about their Pri-
maries. By the Attractive power of the Sun,
joined with the Projectile force of the primary
Planets, they are retained in their orbits; ſo the
action of the Primaries, upon their respective
fecondaries, blended with their projectile force,
will preſerve them in their proper orbits or
ſpheres; all which, with their Primaries, move
round a centre of Gravity, by the univerfal in-
fluence of Attraction.
Lady
On Eclipfes and Tides.
135
Lady L. How very extraordinary it is that
the Heavenly Bodies are permitted to move, and
are reſtrained by fuch wonderful means.
Ment. Every ſyſtem in the univerfe is fup-
poſed to revolve in like manner round one com-
mon centre. In contemplating the order and
regularity which prevails in the various works
of the Creation, we are led to reflect on the
infinite, fupreme wisdom, that planned and ex-
ecuted all the wonders which excite our admi-
ration. We ought from hence, alſo, to derive
the uſeful leffon of an uniform, fteady perfor-
mance of the various duties allotted in our
ſphere of action, as rational Beings; to us, in-
tellectually, God is the centre of all poffible
perfection, the point to which all our hopes
and wiſhes invariably fhould tend. Our frailty
too often cauſes us to fly off in a ſtraight direction
from our proper orbit, and it is only by the
precept, example, and interceffion of our bleſſ-
ed Redeemer, that we are enabled to perform
our deſtined courſe, and ultimately gain the re-
ward of immortal happineſs.
DIALOGUE
DIALOGU E VI.
SATURDAY.
On Light and Darkneſs.
Mentoria.
>
IN endeavouring to defcribe the properties
and qualities of Light, I fhall alſo point
out the effential benefits which arife from its
diffuſive genial influence, and deduce thofe re-
flections which are naturally fuggeſted in fo
intereſting a difcuffion. Various have been the
conjectures and opinions refpecting the nature
of Light, which is now demonftrated to be a
material fubftance, flowing directly from the
Sun. By the term Light, I mean that cer-
tain
On Light and Darknefs.
137
tain principle by which objects are made per-
ceptible to our viſual organs, after a variety of
fpeculations whether thefe impreflions pro-
ceeded from thofe objects or the eye of the per-
fon who viewed them; the difcoveries of Sir
Ifaac Newton have tended to remove theſe
doubts, by eſtabliſhing a doctrine that may be
relied on. According to his fyftem, Light
confifts of a great number of very ſmall parti-
cles thrown off from the luminous body, by an
oppofing or repulfive power, in all directions,
and with an immenfe degree of velocity, from
which it is evident, Light is produced by mo-
tion, but as all motion will not produce Light,
it follows as a natural confequence, that it de-
pends on the quality of bodies, fome of which
are inherently luminous, and have the property
of emitting particles of Light; of this clafs are
the Sun, Stars, and every fort of flame. The
velocity with which thefe particles move is al-
moſt incredible, being computed to be at the
rate of near two hundred thousand miles in a
fecond of time, that is near a million times
greater in proportion than the rapid movement
of a cannon-ball, which is calculated by obfer-
vations on Eclipfes; it has alfo been demon-
ftrated that the progreſs of Light from the Sun
10
$38
On Light and Darkneſs.
to the Earth, is effected in the fhort fpace of
time of eight minutes and three-quarters, though
the diſtance is 95 millions of miles!
Lady L. My aftonishment increaſes as my
knowledge is augmented; how little did I ima-
gine that the Light which is difpenfed to us,
came by fuch rapid means.
Ment. The more we know, the more we
are convinced there remains to be known than
our finite abilities can attain. Perfons of pro-
found knowledge may be compared to deep wa-
ters, that are clear and genuine in their qual
ty, whilft thoſe that are fuperficial in their a –
quirements may be juſtly ſaid to reſemble fhal-
low ftagnate pools, which have only a ſmall
portion of degenerate loofe matter floating on
their furface.
1
Lady L. I hope that fimilitude will not be
verified in me or Lady Mary; my best endea-
vours ſhall be uſed to acquire every branch of
valuable information..
Ment. Attention and application will pre-
vent the evil you dread: profit by the advan-
tages you poffefs; as of all the afflictions inci-
-dent to human nature thoſe only can be deemed
infupportable to which we can attach any felf-
reproach or blame. As I have already explain-
Let
J
ed
On Light and Darkness.
139
រ
ed the velocity of light, I fhall now pro-
ceed to inform you that the particles of which
it is compofed are astonishingly fmall, even be-
yond human conception; it is computed that
from the flame of a candle in a fecond of time
there fly out ten thousand millions of times
more particles of light than there are vifible
grains of fand in the whole Earth. It is alfo
evident that theſe particles of light are emitted
or fent forth in ftraight lines, or what is ufually
called rectilinear motion, which they invariably
preſerve unleſs they are turned from their natu-
ral courſe by what is termed Inflection, Refrac
tion, Reflection, or finally, Extinction.
Lady M. Pray my dear Mentoria explain
theſe terms, as they are above my compre-
henfion?
Ment. Inflection means when light is ob-
ftructed in its path, by the attraction of fume
other body, whereby the progrefs of the ray
is hindered from moving in a ſtraight line. Re-
fraction fignifies when the rays of light by
paffing in an oblique direction through any
body of a different density or thickneſs, do
not afterwards move in ftraight lines, but ap-
pear broken or bent, and as if they originated
from another point, You frequently ſee theſe
{
?
effects,
140
On Light and Darkneſs.
effects, without knowing their natural caufe:
1
thus for inſtance, a ftick when one part is in
water and the other in air, feems broken, and
that part which is in the water, appears higher
than it is in reality. You may alſo experience
the effects of Refraction, by putting a piece of
coin, or any other viſible thing into a tub or
bafon, by receding from which, that you can
but juſt ſee the object, and then by getting a
perſon to fill the tub more than half with wa-
ter, the money, or whatever you have placed
as an experiment, will appear as if it were
removed at a greater diftance from you. The
term Reflection implies, when the rays of light-
are oppoſed by fome intervening body, which
cauſes them to recede. The laſt ſtage of the
luminous procefs, is Extinction, which is occa
fioned, by the rays of light being ſtopped in.
their progreſs by fome body, into which their
fubtle particles effectually penetrate.
•
Lady M. What do you mean by a ray of
light?
Ment. When a fucceffion of the luminous
particles I have juſt deſcribed, follow each o-
ther in a right line, they are denominated rays
of light. Amidst the various properties of light,
none are more extraordinary, than the effect which
Reflection
On Light and Darknefs.
{
141
Reflection and Refraction occafion, particularly
in the production of colours; this fubject I
fhall more fully confider, in my obſervations
on the Rainbow, which is an affemblage of
the moſt beautiful tints.
Lady L. I promife myfelf much pleaſure
from the deſcription of fuch a fine object.
;
Ment. From the obſervations made on the
quality of light, it appears evident, that the
Sun is its primary fource; therefore it follows
as a natural confequence, that from the time
of the Sun's rifing above our horizon, to his
appearing to fink beneath it, we have day, and
from his fetting to rifing again, are involved
in darkness, which conftitutes night. I can-
not mention the Sun rifing or fetting, without
expreffing in fome degree, the fenfations thoſe
glorious fpectacles exhibit; there is a peculiar
quality in folar fplendor which caufes the ima-
gination to foar beyond the height or depth of
human praiſe, or admiration. Who can be-
hold the gilded horizon and the Sun's glory
reflected in the refponfive wide expanfe of the
ocean, and not be awed into a fublime ſenſe
of their Supreme Origin? When the Sun emits
his beams, and exhilarates every furrounding
object, to the contemplative mind, it prefents
a ftriking
4
1
142
On Light and Darkness.
{
a ftriking type of the chearing influence of
Divine favour, whilft the remiffion of his rays
fhould impreſs us with ferious apprehenſion of
being excluded from the participation of re-
fplendent immortal glory, in the realms of
blifs.
Lady M. From your deſcription of Light,
it
appears to me very clear, that the Sun, from
which it is derived, must be a body of fire;
yet you fay Dr. Herfehel is of a different
opinion.
Ment Some Philofophers have fuppofed
the Sun was a maſs of Gold, as that ſubſtance
can bear fire longer than any other metal. On
fubjects fo far above our comprehenfion, and
that cannot by any poffible means be reduced to
certain proof, we should be cautious of receiv-
ing opinions till there appears almoft indubita-
ble grounds for the principles of new theories
or fpeculative fyftems; thofe firmly established
fhould be adhered to, till others can be adopted,
on a more unquestionable and durable bafis ;
though all perfons zealous to make ufeful dif
coveries are entitled to applaufe,' and claim our at-
tention. Some ingenious obfervations have been-
made on the properties of light and heat, by many
modern
On Light and Darkness.
143
modern philofophers.
Dr. Fordyce afferts
that the Sun has probably no inherent heat, and
that the Solar rays are not in themſelves of a
hot quality, but only poffefs, the power of pro-
ducing heat in other bodies. Thefe fentiments
very nearly coincide with thoſe advanced by Dr.
Herſchel, who is of opinion, from obfervations
he has made on the Sun and Fixed Stars, that
they are all moft probably inhabited.
Lady M. That would be impoffible if the
Sun were a body of fire.
Ment. On fubjects of fuch importance we
are incompetent judges, therefore must not be
hafty in our decifions. For the fake of the
argument we will confider the Sun as a ſpheri-
cal body of fire, and yet confiftent with our
ideas of the omnipotence of the Supreme Be-
ing, may acknowledge not only the poffibility.
but the probability of its being inhabited, as that
creative power which conftructed fiſhes to live.
in water, animals on the earth, and birds and
infects in the air, might alfo form beings fuited
to the only remaining element, fire. Exiſtence
is derived from the power of refpiration, being
congenial to the ſtate and condition of each in-
dividual; therefore God could even in this in-
tance deprive fire of its confuming quality, or
render
144
On Light and Darkneſs.
render thoſe who lived in immediate contact
with it, not fenfible of its force: a remarkable
proof of which we find in the miraculous pre-
fervation of Shadrach, Meshach, and Abed-nego,
who were caſt into a fiery furnace by the com-
mand of Nebuchadnezzar and were not even
fcorched by the flames.
Lady L. I am fully convinced that all things
are pollible with God, and acknowledge my
own folly and preſumption in an attempt to
doubt what he wills to perform.
Ment. Thoſe opinions, which are formed on
the immutable foundations of juft principles and
divine truth, never fail to produce the moſt laſting
conviction. As the means of ftrengthening theſe
right impreffions, I fhall add a few remarks on
the various difpenfations refpecting animal life,
which experience has proved beyond contro-
verfy or doubt.
or doubt. In the firft inftance, I fhall
produce the example of the ftructure of filhes,
many of which fubfift at the bottom of the
In this fituation you would imagine
they could not exift, but it is wifely decreed by
Providence that moſt fishes have a bladder or
bag of air, which they are enabled to enlarge or
contract, and by that means to rife or fink, ast
beft fuits their purpoſe: their gills alfo act as
a kind
ocean.
On Light and Darkneſs.
145
a kind of lungs and admit air, with particles of
which water abounds. The next inſtance I
fhall fpecify, are thofe kind of animals which
exift by burrowing in the earth, often far be-
neath its furface, and in a fituation remote from
the aperture they have formed for their entrance
into their fubterranean recefs. Another ſpecies
of extraordinary existence is thofe claffes of ani-
mals that are abforbed in a torpid ſtate during
the whole winter, and in that interval of fom-
nient repoſe, take no ſuſtenance, but are alone
fupported by the peculiar temperature of their
blood, and the degree of fat with which they
are clothed. Theſe unquestionable facts ought
to repreſs our diſtruft of Supreme Power, and
extend our credulity to the utmoſt bounds in all
matters relative to his Divine appointments and
univerſal influence: therefore if the Sun and
Fixed Stars are inhabited, as well as the infini-
tude of Planetary Oibs which form their fyf-
tems, there cannot remain a doubt they have
a juſt proportion of all the bleflings we enjoy as
terreſtrial inhabitants, as they are equally de-
pendant on, and ſupported by an Omnipotent
and Omnifcient Deity.
Lady M. Your reflections on theſe ſubjects
I feel very forcibly; accept, my dear Mentoria,
H
my
€46
On Light and Darkness
my beſt thanks for your zealous endeavours to
improve us.
Ment. The nature of the fubject has caufed
me to digrefs beyond the intent I had originally
formed. I must therefore now refume my ob-
fervations on the influence of Light, to which
I fhall oppoſe the contrary effects of its priva-
tion.
Lady L. Light is fo agreeable, I am almoſt
inclined to wish that we were never deprived of
it.
Ment. Like many other bleffings, the value
of it is enhanced by the contraft which Darkneſs
or Night affords. Light appears to be the fource
of every intelle&ual enjoyment, whether natu-
ral or artificial; it is the means of enlivening
our perceptions and impreffing permanent ideas
of visible objects which could not be obtained
but through that medium. For inſtance, if we
were to hear the fplendor of the Sun's refplen-
dent beams defcribed by the molt eloquent ora-
tor, we ſhould form a very imperfect idea of
its irradiate glory. If the most elaborate pains
were taken to expreſs the varied beauties of the
creation, nothing but ocular demonftration
could impreſs us with just conceptions of the
Deity, which muſt be derived from the convic-
tion
On Light and Darkneſs.
147
n
sion we have of his infinite attributes in the
works of the creation, which combined or fe-
parate, are deſerved objects of admiration, and
juſt claimants of our gratitude and praiſe.
Lady L. I clearly perceive the benefit of
Light, but cannot fo eaſily difcern the advan-
tages of Darkneſs.
Ment. Darkneſs, or the kind of light which
the brighteſt night affords, feems admirably
fuited to the purpoſes of repofe. Animal ſpirits
require a fufpenfion of the exertions and avoca-
tions to which, in a variety of cafes, they are
expofed. The ploughman who is employed
in the moſt laborious offices of agriculture, or
the philofopher who is engaged in the moſt
profound and ingenious reſearches, equally
ftand in need of refreshment from fleep, to which
the ſtillneſs and darkneſs of night moſt benefici-
ally conduce. In Summer vegetation alfo is
cherished by the fame falubrious means, dew
operating the fame on the productions of the
Earth, as fleep does on animals of every kind,
by fhedding a kind of renovating recruit; by
which one attains a fupply of ftrength and ſpi-
rits, the other of freſhneſs and growth.
H 2
Lady
148
On Light and Darkneſs.
Lady M.
I will never again wiſh that there
was no night, as I find it is attended with ſuch
beneficial effects.
Ment. As animals, we may be compared to
machines, or wonderful pieces of mechanifin,
compoſed of various fprings and movements,
compacted and conftructed with confummate
fkill; if thefe powers were always on the
ftretch, they would prove but of very fhort du-
ration. Exercife and reft are the hinges (if I
may be allowed the expreflion) on which our
temporal exiſtence depend; this may be confi-
dered mentally as well as corporeally, as intenfe
application cannot be purfued without intermif
fion, any more than the conftant motion of the
body can be effected without fuftaining a mate-
rial injury. Thus you will perceive it is by the
due accordance of Light and fhade, exertion
and repofe, that the whole ceconomy or ſyſtem
of Nature is fuftained, and our enjoyments ren-
dered fubftantial and permanent.
Lady L. If Light is fo effential to happi-
nefs, how miferable thofe perfons muſt be who
are blind!
Ment. I am convinced that is very far from
being the cafe, which I can affert from experi-
ence, by examples of fome perfons with whom
I have
On Light and Darkness.
149
2
I have been in habits of intimacy. If they are
blind from their birth, they are not fenfible of
the lofs they fuftain by the privation of fight,
and in general they have that defect fupplied,
by poffeffing a taſte for muſic, and are endowed
with a remarkable juft conception of found,
and by touching an object can judge of its qua-
lity they are alſo frequently bleifed with fire
perceptions, which are not diffipated by the fuc-
ceffion of external objects, therefore are very
often intellectually enlightened in an eminent
degree, though in other refpects involved in
darkneſs. It is remarkable, that perfons who
are deprived of fight are uncommonly cheerful;
and when this blindneſs is the effect of diſeaſe
in the optic organs at a mature period of life,
by the recollection they have of objects, can
give their opinion with the most accurate pro-
priety; and from their ideas in a manner being
concentred, are intelligent, agreeable compa-
nions.
Lady L. In future I will not pity perfons
who are blind, fince I find their fituation lefs
melancholy than I imagined.
Ment. That is not the effect I wish to pro-
duce, I have only endeavoured to fhew you,
on the fyftem of the general difpenfation of
bleffings,
H 3
150
On Light and Darkness.
&
bleffings, that perfons deprived of fight, are not
deſtitute of comforts; though undoubtedly they
are objects that excite commiferation, by be-
ing not fufceptible of the cheering influence of
Light, which our viſual powers receive in a va-
riety of pleaſing forms. In the lower claffes
of life, where a fubfiftance is to be gained, they
peculiarly demand our pity and aſſiſtance; as
perfons deftitute of fight, notwithſtanding by
fome extraordinary means they may gain a
maintenance, thofe inftances are comparatively
rare, and in general they have fo many obftacles
to encounter, and fuch great difficulties to fur-
mount, they ſeem to have a fuperior claim to
the moſt munificent effects of public charity
and private pecuniary relief. On this ſubject I
will only add, that it is my earneſt wiſh, when
any opportunity offers for you to realize thoſe
benevolent leffons I fo ftrenuously inculcate; that
you will purfue the means your fympathetic
feelings fuggeft, by giving liberally to the af-
flicted, and with heart-felt fatisfaction propor-
tion your gifts to the feeming neceffities of the
object who claims your affiftance.
Idy M. I will readily obey your injunc-
tions on this fubject, and am certain Lady
Louiſa will unite with me in relieving the blind,
and
On Light and Darkneſs.
151
and every other deſcription of afflicted perfons,
as acts of charity are productive of the higheſt
fatisfaction.
Ment. It is worthy of obfervation that two
of the greateſt geniufes who have produced har-
mony of the most exquifite kind, in poetry and-
muſic, were both blind; it is almoſt needlefs
to add, that I mean Milton and Handel, and
it is highly probable their imagination would
not have foared to fuch heights of excellence, if
their viſual organs had been able to contemplate
external oftenſible objects; ſo that their misfor-
tunes, perhaps, proved the means of rendering
their fame immortal.
Lady M. I fhall admire the works of Mil-
ton and Handel more than ever, now I have:
heard they were both afflicted by the lofs of
fight.
Ment.
Excellence of every fpecies demands
our applauſe; but that fuperior kind which a-
rifes from fuch extraordinary inftances of per-
fection in any Art or Science, as what this
great poet and muſician attained, is of a nature
to excite our admiration to almoſt an enthuſiaſtic
pitch. As theſe eminent perfons are equally
diſtinguiſhed by the fublimity of their reſpective
compofitions, they may not unaptly be com-
pared
H 4
152
On Light and Darkneſs.
pared to the Planets, which from being dark, or
opaque, tranfmit the light of the Sun by the
powers of reflection; and with juſtice their
bright genius may bear fome degree of fimili-
tude to that glorious luminary, as their effects
are of the moſt brilliant quality, and muſt, from
their fuperior luftre, be derived from a Divine
fource!
1
DIALOGUE
DIALOGUE VII.
MONDAY.
On Air, the Atmoſphere, and
Sound,
As
Mentoria.
SI flatter myſelf with the hope that you
have now a juſt conception of the Celeſ-
tial Bodies, I ſhall zealouſly aim to inſtruct you
in fome important branches of Natural Philofo-
phy, as they appear collaterally connected with
my Lectures on Aftronomy. After having ex-
plored the wonders of the Firmament, it be-
comes in ſome degree neceffary to examine the
quality of that thin tranfparent fluid body, de-
nominated Air, which furrounds the Terra-
H 5
queous
154
On Air, &c.
queous Globe we inhabit, and covers it to a
very confiderable height. In the definition of
this fluid mafs, if we include the conftituent
parts of air, watery, and other vapours, electric
matter, &c. which encompafs the whole Earth,
and participate of its motions, we call it the
Atmoſphere, as a general term.
Lady M. I recollect hearing you frequently
mention the Atmoſphere; pray, my dear Men-
toria, be kind enough to explain what it is?
Ment. The Atmoſphere is a body of Air,
confifting of aqueous vapour, blended with a
mixture of heterogeneous particles, exhaled from
all folid and fluid fubftances on the furface of
the Earth this compound etherial matter fur-
rounds the Globe, through which the Sun's rays
paſs before they reach it; in their progrefs they
do not move in ſtraight lines, except when the
Sun is at the zenith, or directly over our heads;
but when they reach our Atmoſphere they bend
downwards, which produces what is called
Crepufculum or Twilight. The rays of light
pointing upwards from the Sun before he rifes,
and after he has fet, bend towards the Earth
upon reaching the Atmoſphere; and in conſe-
quence it begins to be light in the morning
when the Sun arrives at 18 degrees below the
Eaftern
On Air, &c.
155
Eaftern horizon, and continues to be light in
the evening till he has funk 18 degrees below
the Weſtern horizon.
Lady L. What do you mean by the rays
light bending downward?
of
Ment. This is produced by Refraction, and
is cauſed by their paffing in an oblique direction
from one medium to another, as from Air into
water, or water into Air. As I explained this
matter very explicitly in my definition of Light,
I ſhall ſay no more on that ſubject at preſent.
Lady L. Pray Mentoria inform us of all
the properties compriſed in the Atmoſphere.
Ment. It is a thin invifible fluid, more
denfe or heavy near the Earth, but gradually is
of a lighter quality the higher we afcend; there-
fore at the fummit of fome high mountains it
is fcarcely poffible to breathe. The Atmof-
phere ferves not only to fufpend the clouds, to
ſupply us with wind and rain, but to furniſh
us with the means of refpiration; it alfo pro-
duces the morning and evening twilight, as I
have juſt deſcribed. This body of Air, which
is termed the Atmoſphere, is about 45 miles
above the furface of the Earth, therefore the
Sun's rays falling upon the higher parts of it
before rifing, by Reflection cauſes a faint light,
H 6
which
-
156
On Air, &c.
which increaſes till he appears above the hori-
zon, and in the evening it decreaſes, till he is
18 degrees below the horizon, when the morn-
ing twilight begins, and the evening twilight
ends.
Lady M. I never before thought by what
means I breathed, or what produced Light,
Rain, or Wind.
Ment. It is a common but much to be la-
mented proof of human frailty, that we fre-
quently enjoy bleffings, without being able phy-
fically to account for them.
Lady L. What do you mean by the term
Phyſically? that expreffion feems to relate to
Medicine.
Ment. Its more extenfive fignification im-
plies any thing that can be accounted for by na-
tural cauſes, fuch as the various branches of
Philofophical inquiry; but all matters beyond
the power of human ability to folve or demon-
ftrate, are faid to be Metaphyfical, a term par-
ticularly appropriate to Divine fubjects. The
Atmoſphere is the fource of almoſt every terreſ-
trial comfort we enjoy; it is the medium through
which we obtain the light of the Sun, the re-
freſhing falubrious breezes of the Air, vegeta-
tion, and every relative and combined effect ef
fential
On Air, &c.
157
}
ſential to exiſtence. In proportion to the qua-
lity of the Atmoſphere that furrounds us, we
are faid to be in a good or bad temperature;
Air is the vital principle of life, and our lungs
the organs of reſpiration, by which fuch a por-
tion is imbibed as is neceffary for the recruit of
the animal ſpirits, and the fupport of our gene-
ral ftamina.
Lady L. I had no idea of the beneficial con-
ſequences of the Atmoſphere.
Ment. When you perceive the day appear
bright, and the profpect cur horizon affords
clearly vifible, you may then be convinced the
Atmoſphere enables you to difcern theſe pleaſing
objects; as if there were no Atmoſphere, the
Sun would yield us no light but when our eyes
were directed toward him, and the heavens.
would appear dark, and as full of ſtars as on a
dreary winter's night; but the Atmoſphere, by
being ſtrongly illuminated by the Sun, reflects
the light back upon us, and cauſes the whole
heavens to fhine with fo much fplendor, that
the faint light of the Stars is obfcured, and by
that means rendered invifible.
Lady M. I am very happy that I am now
convinced of the advantages we derive from the
body of Air that furrounds the Earth; I am
thank-
158
On Air, &c.
thankful for every freſh branch of knowledge I
acquire.
Ment. Learning (which is a perverted term,
unleſs expreffive of uſeful information) is the
greateſt treaſure that you can poffefs. Riches
may diminiſh, but knowledge cannot fail to in-
creaſe, provided you uſe the natural means that
we are all endowed with, to acquire this defira-
ble poffeffion. The ignorant pafs through life
as it were blind-folded; as they obferve nothing
beyond the common perceptions of their natural
fenfe; therefore wonder on fubjects that are
plain and fimple in their effects; and from their
few reſources of information, are not fenfible of
the great advantages that are derived from a
highly cultivated underſtanding, which like the
diamond, ever ſhines with refplendent luftre.
Lady L. I hope you have not finiſhed your
account of the different qualities and effects of
Air.
1
Ment. As I have already fpecified the vari-
ous advantages we derive from the Atmoſphere,
as being effentially neceffary to exiſtence and the
production of vegetation, it may be proper to
add thoſe of Sound, Rain, and Dew. Air dif-
fers from other fluids in the following inſtances.
It is capable of being compreffed into a much
lefs
On Air, &c.
159
<
lefs ſpace than what it naturally poffeffes; it is
of a different thickneſs or denfity in every part
upward from the furface of the Earth, decreaf-
ing in its weight in equal proportions, the higher
it rifes, and confequently muft decreaſe in den-
fity; it is alfo of an elaftic nature, and the ef-
fect of this fpringy quality is proportionate to
the force by which it is compreffed; and the
elaſticity of the air is encreaſed by heat, and
diminiſhed by cold.
Lady L. I have heard perfons frequently
mention the weight of the Air, but I did not
know their caufe for fo doing.
Ment. Moft probably their obſervations a-
rofe from their perception of the denfe quality
of the furrounding Air, unconnected with the
philofophical grounds they had for that affer-
tion. The variations in the weight of the Air,
ariſe in a great degree from the different portions
of heat which are in the etherial fluid near the
Surface of the Earth; and alfo from the changes.
in the Atmoſphere, caufed by the viciffitudes of
winds and vapours. It is computed there is a
preffure of Air equal to 15 pounds avoirdupois
weight, upon every fquare inch; therefore it is
calculated that a human being of full fized di-
menfions
160
On Air, &c.
£
menſions ſuſtains the aftoniſhing burthen of
21,600 pounds.
Lady M. I am amazed they are not cruſhed
by ſuch an immenfe load.
Ment. Great as that preffure is, the divine
will and power could increafe it to any degree
his providence ordained; however we may fafe-
ly rely that the denfity of the atmoſphere like
the revolutions of the Celeſtial Bodies and every
other part of the Univerfe is directed in its
operations by Supreme Wifdom.
Lady L. I fear you have compleated your
differtation on Air, which I greatly regret.
Ment. As far as relates to its genuine ſtate
when not fubject to motion, though there re-
mains a very effential branch for me to difcufs,
which compriſes the variations its agitations pro-
duce in what are ufually called the wind,
which is in effect a ſtream of air that proceeds
from one region to another. In fome parts of
the torrid zone there are regular winds which
blow invariably from the fame point, theſe are
called trade-winds and are of great utility, as
ſhips when they attain to a certain degree of la-
titude and longitude are ſure of having proſper-
ous gales: there are alſo ſome particular parts
between the tropics, where the winds blow pe-
riodically
On Air, &c.
161
riodically for the ſpace of fix months in one
courfe and fix months in the contrary direction,
thoſe are called monfoons; theſe and other ref-
pective variations are exemplified on the globe
by arrows pointing different ways, which I in-
treat you will obferve with great attention, I
therefore will be the more concife in my re-
marks on that fubject. Winds are more uni-
form in their courfe on the fea than on the land,
which is occafioned by the temperature of the
latter being affected by the influence of electri-
city, volcanoes, exhalations and meteors. It
is alſo obſerved that the Eaft wind and thofe
which come from the Poles are ſtronger than
the Weſt and thoſe which proceed from the
Equator; whilft on the contrary, the Weft and
South winds are more or lefs violent than the
Eaft or North winds. Winds are more tre-
mendous in their effects in mountainous fitua-
tions than in plains; and the higher we go the
greater we experience the force of the wind,
till we attain the common height of the clouds,
which is nearly one quarter of a league per-
pendicular height, beyond which the ſky is gene-
rally ferene, more particularly in the Summer fea-
fon, and the wind imperceptible even on the fum-
mit of mountains. In continental countries the
winds are not only variable but produce extraordi-
nary
162
On Air, &c.
:
•
nary effects, fuch as the heat of Summer be-
ing experienced on one fide of a mountain and
the rigour of Winter on the other. During the
Summer ſeaſon in Egypt hot Southern winds
are very prevalent, which fufpend the breath
and raiſe fuch a quantity of fand of a quality fo
fine and fubtle it penetrates into every object,
and often caufes peftilential difeafes. The moft
tremendous effect of wind is what is uſually
called hurricanes, in which the wind feems to
proceed from all directions and produces a whirl-
ing kind of irreſiſtible motion that is inexpref-
fibly awful and fatal in its effects; a calm ge-
nerally precedes thefe dreadful tempefts.
Whirlwinds are produced by the conflicts of
fudden rarefaction when contrary currents of air
meet in the fame place. I have been thus par-
ticular on this fubject as it muft frequently oc-
cur in common diſcourſe, and you are no doubt
informed the four cardinal or chief points the
wind blows from are North, South, Eaft and
Weft; therefore the quality of the weather na-
turally in a great meaſure depends, from which
of thoſe the current of air proceeds. I muft
now endeavour to give you fome idea of the
properties of Sound.
Lady
On Air, c.
163
Lady L. I think that will not be very dif
ficult, as we are all fenfible of its effects.
Ment. But I am doubtful whether you
know by what caufe they are produced. Sound
is the natural confequence cauſed by an agitation
of the air, arifing from the tremulous motion
of the parts of any fonorous body when ſtruck
upon, which by occationing the air around it to
vibrate to a certain diſtance, conveys the Sound
to the ear that is within the reach of that vibra-
tion and various experiments which have been
made on the air-pump clearly demonftrate that
Sound cannot be produced without air, as on
the motion of its particles it entirely depends.
It is by this elaftic force that Sounds are conveyed"
to the organ of hearing, which is wonderfully
conftructed not only to receive the impreffion
but to convey it to the brain which is the feat
of perception, and from the concurrent opera-
tions of thefe extraordinary inftances of divine
fkill, we are fufceptible of a variety of fenfa-
tions arifing from the influence of Sound. In
the variations and proportions theſe act upon
our feelings, they are faid to be pleaſing or pain-
ful in their effects, as a certain degree of har-
mony or coincidence is neceffary to render them
accordant to our fenfitive perceptions. Mufic
is
164
On Air, &c.
is unquestionably the moft refined and difun-
guiſhed effect of the property of Sound, and
by its influence on the paffions, and intellectual
powers, may be confidered to comprize the
general œconomy of the do&rine of Sound.
Lady L. I am extremely delighted with
mufic of every kind, and thall in future pay
great attention to the different kinds I hear.
Ment. Mufic from its general pleafing.
effects, is a fcience almoft univerfally admired,
and very frequently perfons acquire a great de-
gree of perfection in the practical parts; moſt
of whom I make no doubt are ignorant, that
the different Sounds produced by different in-.
ſtruments, are occafioned by their peculiar con-
ftruction, and the natural confequence of the
properties of air, which tend to conſtitute
thofe variations of tones, which are compre-
hended in the compound term, of Mufic.
Lady L. It is furpriſing at what diſtance
one can perceive any noiſe.
Ment. Sound moves at the rate of 68,520
feet in the ſpace of a minute; or 1142 feet in a
fecond or moment: this computation will en-
able you in fome meaſure to account for the
diftant perception of Sound; as the rapidity
with which it is conveyed to our auricular or-
gans,
On Air, 3%.
165
gans, is with a degree of velocity almoſt beyond
the powers of our comprehenfion: thus you
perceive, that even what you hear, comes
through a medium, and by a means which can-
not fail to excite your wonder and admiration.
There yet remains a curious Phænomenon
refpecting Sounds, which I will briefly explain:
you have frequently heard, an Echo, this like
many natural caufes is commonly perceived,
though but rarely traced to its original caufe.
An echo is produced by the vibrating air being
obftructed in its paffage. The undulating mo-
tion of the air, in its progreffive courſe fre-
quently meets with repellant objects, and by
ftriking against them is reflected back to us,
and occafions new vibrations, which if the ob-
ject is in a proper fituation, repeats the fame
word or found first formed, and this fometimes
not only once, but by feveral diftinct repetiti-
ons.
Lady L. We are much obliged to you, my
dear Mentoria, for giving us a juſt notion of
an echo; there are fome places in our park,
and gardens, which produce that Phænome-
non.
Ment. You will now be convinced this
conſtant effect arifes from fome permanent
obftruc-
166
On Air, &c.
obftruction of the current of Sound, which
cauſes it to return to you the very word or
tone you uttered. As I have enumerated the
general effects of Air, I thall now endeavour
to fubjoin fome appofite reflections on its uni-
verfal beneficial qualities. Air like every other
fpecies of matter, is expanded by an increaſe
of fire, or heat, blended with its particles, in
which ſtate it is faid to be rarefied. As a proof
of its elaſticity, the greateſt degree of cold is
never able to deftroy its fpringy quality, as the
particles of which Air are compofed are fub-
ject, like every other fpecies of matter to the
laws of gravitation, they are expanded by a
decreaſe of its general maſs or quantity.
Lady L. Pray my dear Mentoria do not
conclude your remarks on Air.
Ment. I will extend them fo far as to
fhew you that Air, not only contributes to
produce animal, and every other degree of heat
neceffary to exiſtence, but alſo what is called
combuſtion, by which you are to underftand
any body or fubftance that may be burned or
deſtroyed by conflagration.
Air may properly
be faid to be the fuel of fire, as by conbining
with combuftible matters, the Air is condenfed
or deſtroyed by the fire being emitted, which
kept
On Air, &c.
167
kept it in a ſtate of elafticity. Every animal is
poffeffed of fome means of afpiration or breath-
ing, by which they can acquire as much Air
as is proportioned to their conftruction, and
other relative circumstances of exiſtence. The
greater part have lungs, and others that have
not, have that defect ſupplied by a kind of blad-
der, by which ſuch a portion of Air is imbibed,
as ferves the purpoſe of ſupporting animal
life; most infects are endued with a kind of
tube, which ſerves as a ſubſtitute for lungs, and
enables them to gain as much Air as their ſtate
and condition requires. It is not alone to the
animal part of the Creation, that the diſpenſing
hand of Providence has been fo diffufive in its
bleffings, as vegetables are alfo furniſhed with
tubes or pipes, by which they receive fuch a
portion of Air, as not only tends to their exift-
ence, but their growth; this is not merely ef-
fected by the fibrous parts of the roots, but alſo
by thoſe which are fituated on the leaves, as
Air conftitutes an effential part of vegetative.
preſervation.
Lady M. I am almoſt aſhamed, when I re-
flect, that I have breathed without being fenfible
of the importance of Air, and have feen all the
effects
1.68
On Air, &c.
effects you deſcribe, perfectly unconſcious of
their important ufes, and divine fource.
Ment. In your cafe, there is neither cauſe
for regret, nor reproach. Youth is the period
of life, in which information is to be gained;
we cannot be wife by intuition, Inſtruction is
the general medium by which you are to obtain
knowledge, and obfervation and experience are
the auxiliaries that tend to complete the great
end of effential Improvement. Education ope-
rates on the mind, as Air does on the body;
it expands, it animates, and vitally fertilizes the
whole intellectual fyftem.
DIALOGUE
DIALOGUE VIII.
TUESDAY
On Electricity and Magnetiſm.
You
Lady Louifa.
have explained many very furpriſing
things to us; pray, my dear Mentoria give
me fome idea of Electricity?
Ment. Electricity is that peculiar quality
which fome bodies poffefs, that after having been
rubbed, and by that friction heated to a certain
degree, acquire a power of attracting and repel-
ling other bodies, and frequently of emiturg
fparks of fire. All fuch bodies as have this
inherent quality, and require only a certain de-
gree of friction to excite it, are called Electrics,
I
and
170
On Electricity
•
and all thoſe which have not this property, and
can only receive it by communication with elec-
trified bodies, are denominated Non-Electrics.
Thales, the Milefian, was the first who difco-
vered the electrical properties of amber, by
attracting light bodies when it was rubbed, a-
bout 600 years before the Chriſtian æra; and
nearly at the period of 300 years previous to
that epocha, Theophraftus obferved that the
Lyncurium, a fubftance now called Tourmalin,
had the fame attractive property. From this
period to the 17th century, this branch of Phi-
lofophy appears to have been neglected, except-
ing that Mr. Bofe diſcovered that Jet and A-
gate were poffeffed of electric properties. About
the year 1600, Dr. Gilbert, by various obfer-
vations, extended the difcoveries refpecting the
variety of other electric bodies. In the year
1670, Mr. Boyle greatly enlarged and improved
the Science of Electricity; but to Sir Ifaac
Newton, who flourished at the clofe of the 17th
century, we are indebted for many valuable
difcoveries, who afcertained that the electric
attraction and repulfion penetrated through
glafs. After this period a variety of modern
philofophers have made great improvements in
this part of Natural Philofophy.
Lady
and Magnetifm.
171
Lady M.
How frequently you mention
Thales and Sir Ifaac Newton as being the cauſe
of great diſcoveries in fcience; how very fupe-
rior their merit muſt have been!
}
Ment. They were both fignally diftinguifh-
ed by their learning and abilities. Thales was
one of the ſeven wife men of Greece, and Sir
Ifaac Newton one of the most brilliant geniufes
that this, or perhaps any other country ever pro-
duced. I muſt now recal your attention to the
properties of Electricity, which are to attract or
repel all kinds of very light bodies at a fenfible
diſtance, when the attracting body is heated by
friction, which is in cffect nothing more than
the attraction of Coheſion, excited by a strong
attrition to act with lefs force in a larger fphere,
fuch as amber, jet, fealing-wax, glafs, &c. It
will be beyond my purpoſe to enumerate each
fubſtance endued with this property, I fhall
therefore briefly divide them into the following
claffes: metals, fuch as gold, lead, copper,
iron, fteel. Animal fubftances, bones, fhells,
hair, &c. &c. Vegetable fubftances in infinite.
variety. Corallines, or marine productions of
fponge, coral, &c. &c.
fubftances, and, laftly,
I
2
}
Foffils and mineral
artificial fubftances,
namely,
172
On Electricity -
namely, china-ware, glafs, elaſtic gum, filk,
&c. &c.
Lady L. By what means are theſe effects
produced?
Ment. The electric property in fome in-
ftances may be proved by the fimple proceſs of
friction, though its philofophical ſyſtematic
ufes are aſcertained by an ingenious apparatus,
called a machine. The principal parts of theſe
electrical machines are the Electric, the Moving
Engine, and the Prime Conductor; theſe curi-
ous pieces of mechaniſm conſiſt of globes, ſphe.
roids, cylinders, wheels, &c. fo conftructed as
to produce the effect of Electricity. Their va-
rious forms and qualities would carry me be-
yond my prefent purpofe; 1 fhall therefore only
mention, that formerly a variety of fubftances
were uſed as Electrics in theſe machines; but
at prefent finooth glass globes are very generally
adopted.
Lady M. I have heard of many of our
friends being electrified; what advantages did
they derive from it?
Ment. We are compofed of the Elements,
Earth, Air, Fire and Water, which are our
component or conſtituent parts.
Lady
and Magnetifin.
173.
Lady L. I cannot comprehend this matter;
pray my dear Mentoria be more explicit on that
fubject.
Ment. Our corporeal frame is compriſed
of folids, and fluids; the folids are evidently
Earth, as in the Scriptures we are expreſsly
told, duſt we are, and unto duft we fhall return.
The fluids, which confift of blood, and other
juices, have a great proportion of water in their
compound; and it is evident that breath which
is the chief principle of exiftence is derived from
Air; therefore there only remains to prove that
we poffefs alfo a portion of Fire, as well as of
the other Elements blended in our compófition,
which Electricity demonftrates beyond a doubt,
Lady M. I can fcarcely believe we have
Fire in our compofition.
Ment. This quality is philofophically ter-
med animal heat, by which is to be underſtood
that principle, which is produced by the agita-
tion of the body, and the fire contained in it,
which excites the idea of heat in our minds,
and in the body thus heated, is merely the
effect of motion. Various are the opinions.
reſpecting animal heat, though it appears moft
probable, that the abfolute heat, which is fepa-
rated in reſpiration, and abſorbed by the blood,
I 3
is
374
On Electricity
is the genuine caufe of the portion of this ele-
mentary fluid, which is difperfed through our
general mafs, and almoft in every other com-
pofition namely in plants, in moſt ſpecies of
trees, the bores, feth; and blood of animals,
which is evident from their combuftible quality
when dried; alfo in minerals and a variety of
other things. In this inftance, there is pecu-
liar caufe for gratitude, that this active fluid
fire which is incorporated in our frame, is kept
in due bounds refpecting its operation, by the
effects of Divine wifdom. I hope you are now-
convinced you are compofed of the Elements,
which is a term expreffive of the original fimple
or unmixed parts of any body, or that to which
it is ultimately refolvable.
Lady M. I recollect ſeeing a lády electri-
fied, and it ſeemed to be a very ingenious appa-
ratus that was uſed to produce that effect; in
what refpect could it prove beneficial to her
health, as fhe was in an invalid ſtate?
Ment. This branch of Philofophy, which
is converted to medical purpofes with great fuc-
ceſs, has been brought to a furpriſing degree of
perfection. In paralytic, and other cafes that
require a ftimulus, Electricity often produces
the happieft effects; but like all other remedies
powerful
and Magnetiſm.
175
powerful in their operations, they ſhould not be
adopted, but by the advice and under the im- '
mediate direction of the moſt ſkilful practi-
tioners.
Lady M. I heard once of a perfon receiv-
ing fuch a fhock by touching fome electric pow
er, that it had nearly proved fatal.
Ment. The confequences of the electric'
force in many instances have been tremendous :
a very melancholy accident happened in 1753
to profeffor Richman at Petersburg, as he was
making experiments on lightning, which he had
drawn into his chamber for the purpoſe of af-
cêrtaining its electric qualities; when dreadful
to relate, juſt as he was going to prove philofo-
phically the proportion of electric fire, a ball
of fire iffued from the lightning, ftruck him
dead, and conſumed and deſtroyed moſt of the
things in the room.
Lady M. How much the death of ſuch an
ingenious man is to be lamented, particularly
as he was feeking to gain freſh knowledge.
Ment. Perfons who die in fuch a glorious
cauſe may be confidered as martyrs to the gene-
ral good of mankind. I recollect an inftance.
equally unfortunate, and in many refpects fimi-
lar, in the death of the elder Pliny who loft his
I 4
life
176
On Electricity
life by his determined refolution to obſerve the
effects of the dreadful eruption of Mount Ve
fuvius which happened A. D. 79. He was
in vain adviſed to recede from the danger that
threatened him, by exploring this tremendous.
abject too nearly. As Pliny had at this awful
feaſon a fleet of fhips under his command, he
ordered the gallies to put to fea, with the hope
of rendering fervice to his friends on the coaft,
as well as to fatisfy his laudable philofophical
curiofity. After various difficulties he at length
determined to go on fhore to his friend Pompo-
mianus at Stabia, in the gulf of Naples, obferv-
ing when he debarked, "Fortune befriends the
brave." In the extremity of diftrefs this erup-
tion caufed, by the fire, fmoke, and cinders
that iffued from it, the people were involved in
inextricable danger; therefore, whilft on the
fhore deliberating whether to go on board his
fhip again, this great man was fuffocated, as it
was imagined, by fome noxious vapour from
the eruptive matter.
Lady L. I feel much regret that two ſuch
eminent men fhould have fallen facrifices to
their eager purſuit of ſcience.
Ment.
To die is the common lot of human
nature, but to expire heroically is the fate only
of
and Magnetifm.
177
of perfons of diſtinguiſhed bravery and magna-
nimity of foul. A fenfe of danger will never
operate to retard a truly great mind from en-
gaging in any noble enterprize, as Glory is
more valuable than life!
J
Lady M. The melancholy fate of Profeſſor
Richman will make me fearful of being electri-
fied, if ever that remedy fhould be advifed for
my benefit.
Ment. You might with as much propriety
never eat any grapes, as the Grecian poet Ana- .
creon was choked by fwallowing that fruit; and
a number of cafes might be adduced, that would
excite dread on every fubject, if thoſe fenfations
were not counteracted by truft and implicit
confidence in Divine protection. To quell
your fears on this occafion, I can fafely affert
that a judicious operator in Electricity, poffeffes
the ſkill of proportioning the degree of the fhock
produced by the electric quality, to the circum-
ftances of the cafe; and by that means even the
eye, which is of a most delicate texture, can
receive a flight touch of its force, which is often
productive of the greateſt advantage. This like
many other things is poffeffed of great utility
when properly applied, but deftructive when
perverted or abuſed. As a means of entertain-
ment,
1:5
178
On Electricity
ment, many ingenious experiments are made
that come immediately under the clafs of Lec-
tures upon Natural and Experimental Philofo-
phy, from which much improvement is de-
rived.
Lady L. I now clearly underſtand the pro-
perties of Electricity, and am greatly obliged to
you for the information.
Ment. The next fubject I fhall difcufs is
Magnetifm, a wonderful phænomenon that is
produced by the power of the Magnet or Load-
itone, which is a mineral that has the property
of attracting and repelling iron.
Lady M. I have heard the Loadſtone fre-
quently mentioned; therefore, my dear Men-
toria, let me intreat you to be very explicit re-
fpecting its qualities.
༔
Ment. The Loadſtone, or Magnet, is a
kind of ferruginous ftone, in weight and colour
refembling iron ore, though rather of a harder
fubftance and heavier quality, endued with
the powers of attraction. It is fuppofed to have
derived its name from Magnefia, a part of the
ancient Lydia, where it is faid to have been first
found; though many imagine it was fo called
from a fhepherd named Magnes, who firſt dif
covered its attractive qualities, by the iron in
his
and Magnetism.
179.
his crook, on Mount Ida.
This wonderful
production is ufually found in iron mines, fre-
quently in large pieces, half iron and half Mag-
net. The beſt Loadſtones are brought from
China and Bengal, which refemble iron in hue;
it is also found of various dimenfions, and in a
great number of different places; thoſe of Eng-
land, Germany, and Hungary have a ſtrong fi
militude to unwrought iron.
Lady M. I have feen a Magnet attract a
needle, and obſerved when the Magnet was held
up, the needle appeared to be faftened to it, till
it was removed by force.
Ment. This extraordinary circumftance was
moft probably produced by what is called an
Artificial Magnet, which is a piece of poliſhed
fteel impregnated with a magnetic quality. The
effect you defcribe may be produced at any time,
if you place a bit of iron near to one end of a
Magnet, which will clearly prove its power of
attraction. Every Magnet has what are called
its North and South Poles, one of which has a
repellant force to drive backwards the fame
piece of iron which the other will attract.
Lady M. By what means was the uſe of the
Loadſtone difcovered?
I 6
Ment
180
On Electricity
·
Ment. Its attractive powers were known in
the early ages of the world. Thales, the Mi-
lefian Philofopher, who flourished about 600
years before the Chriftian æra, furprized at its
conftant effect, afcribed to it the property of a
foul. Ariſtotle and Pliny have mentioned its
magnetic quality: but it was not till the twelfth
century that it was diſcovered invariably to point
to the North. The knowledge of theſe extra-
ordinary properties prepared the way for the
grand diſcovery of turning them to advantage
in nautical matters. The only uſe the ancients
made of this mineral fubftance was, as a remedy
for burns and defluxions of the eyes: happily
for fucceeding generations its more important
utility has been afcertained, as in the fourteenth
century the mariner's compaſs was brought into
ufe, and after various improvements has attain-
ed its prefent perfection. To the diſcovery
of the attractive power of the Loadftone, we
are indebted for the invention of this uſeful in-
ftrument; as by obferving the invariable ten-
dency of a magnetic needle to point to the
North, it has proved of the greateſt ſervice in
determining the courfe of fhips and the variation.
of the winds.
Lady
and Magnetiſm.
131
Lady M. Pray my dear Mentoria explain
the conftruction of this valuable machine.
Ment. The mariner's compafs is of a cir-
cular form, and has a kind of dial-plate divide d
into thirty-two equal parts, by right lines drawn
from the centre to the circumference, which are
called the points of the compaſs; the four prin-
cipal ones, viz. Eaft, Weft, North, and South,
are termed the Cardinal Points. Over this
dial-plate is fufpended a thin piece of iron,
which being touched by a magnetic virtue, by
that means its two Poles are made to point
nearly to the North and South Poles of the
World; this is called the Magnetic Needle,
and ferves the important purpoſe of directing
failors what courſe they are to purfue.
Lady L. I cannot yet clearly underſtand by
what means the Loadſtone is fo uſeful to navi-
gators.
Ment. The compaſs may be invariably re-
lied on as their guide, for however the ſhip may
change its fituation, the Magnetic Needle before.
deſcribed conſtantly points to the North, and
by obſervations on the other parts, they are ena-
bled to purſue the courſe that leads to the object
of their deſtination, and to avoid what would
fteer them from it,
Lady
182
On Electricity
}
Lady M. Who first invented the Mariner's
Compass?
Ment. This valuable difcovery is ufually af
cribed to Flavio da Melfi Gioai, a Neapolitan,
about the year 1302, in confequence of which,
Principato, his native place, bears a Compaſs
for its Arms. Others are of opinion that Mer-
cus Paulus, a Venetian, A. D. 1260, made a
journey to China, and brought back this uſeful
invention: thofe who fupport this belief, al-
ledge that when firft the coinpafs was uſed, it
was on the fame conftruction that is at preſent
adopted by the Chineſe, by having the Magne-
tic Needle floating on a piece of cork, inſtead
of being fufpended on a pivot; it is alfo fup-
poſed that the Chinefe had fome knowledge of
the Loadſtone's properties 1120 years before the
Chriftian æra, as Chiningus their emperor was
a great aftronomer, and they affert made this,
amongst many valuable difcoveries. The French
alſo put in a claim for the honour of this inven-
tion, from the circumftance of the Fleur de Lys
being generally uſed as a fign to denote the
North on any map or globe. The English
form the plea for their fhare in this diftinguifh-
ing honour, by the word compafs being adopt-
ed for the appellation of this ufeful inftrument,
}
as
and Magnetism.
183
as that word is ufed by them to express circuit
or extent; and though they cannot afpire to the
fame of the invention, they are moſt likely en-
titled to the credit of having brought it to per-
fection, by fufpending the box that holds the
Magnetic Needle. I have enumerated the moſt
próbable fources of the valuable difcovery of the
Mariner's Compaſs; though it is afferted by
the French, that they had a prior knowledge of
the Magnetic properties, as being of great uti-
lity in navigation, from the circumſtance of
ſome verſes being extant, written in praiſe of
the Marinette, or Mariner's Stone, in the year
1200. At fuch remote periods it is not poſſi-
ble to aſcertain decifively on any controverted
point; it is therefore beft to embrace thofe opi-
nions which are the most generally received.
་
Lady L. By what means did failors conduct
their fhips, before there were any Compaffes?
Ment. Previous to the diſcovery of the Polar
Star and the attractive powers of the Loadſtone,
navigation was limited within very narrow
bounds. The greateſt enterprizes that were
undertaken, and the principal traffic that was
carried on by the ancients, were effected by
coafting; the mariners being afraid to quit the
ſhores and launch into the main ocean, as they
were
184
On Electricity
were poffeffed of no fpecific rules to aſcertain
their respective diftances and courfes. The
Phoenicians were the first who obtained the
knowledge of the Polar Star; and they com-
municated this valuable difcovery to the Ionians
and other Grecian ftates, about 600 years be-
fore the Chriſtian epocha. This circumſtance
will convince you that we are indebted to the
Phoenicians for the first rudiments or elements
of navigation. Tyre and Sidon, the chief ci-
ties in the Phoenician diftricts, were the centre
or emporium of trade in thoſe remote times;
therefore the hope of extending their commerce.
made them zealous to adopt every means that
could increaſe its channels, as their wealth and
confequence were derived from no other ſource,
their country being inconfiderable in extent,
and from their intenfe application, to traffic,
its cultivation in a great meafure neglected. In
a progreffive furvey of nautical improvements,
it appears evident, that from the indefatigable
purſuits of the Tyrians and Sidonians, and their
conſtant regard to the direction of the Polar
Star, we derived the knowledge of the coafts of
the Ocean, and thoſe of the Mediterranean Sea,
on the moſt Eaſtern part of which Phoenicia was
fituated. Theſe commercial people extended their
traffic
*
and Magnetiſm.
185
traffic to Africa and many diſtant regions in A-
fia, and fettled ſeveral colonies in various parts,
which ſerved the purpoſe of eſtabliſhing a ge-
neral mart for all valuable commodities.
Lady M. In this inftance the Phoenicians.
appear to have had great merit; but who were
the first who had courage to explore the Ocean,
and undertake the valuable difcoveries we read
of?
Ment. Theſe important effects have been
produced by the knowledge we have attained
of the Loadſtone's wonderful powers. When
their properties were fully known, many ſtates
availed themſelves of the benefits derived from
them, and in confequence feveral important
difcoveries have been made; but the moſt emi-
nent and earlieſt example we can find, is the
great and fuccefsful enterprize of Columbus,
A. D. 1492, who traverfed an expanſe of O-
cean, unknown but to his great ideas, and by
compafling his intrepid undertaking, afcertain-
cd an immenfe extent of continental country,
and a great number of islands, which comprize.
the regions of America, and what are ufually
called the Weſt Indies, from which many va-
luable productions and great wealth are ob-
tained. The ancients had a knowledge but of
a ſmall
186
On Electricity
a fmall part of the Globe, all America and the
internal regions of Africa were wholly unknown.
to them: they were ignorant of the flux and re-
flux of the Sea, and were not convinced the
Ocean furrounded the Globe entirely, though it
was in fome degree fufpected; but none ven-
tured to attempt a voyage round the World, till
A. D. 1519, when Magellan, a Spaniard, un-
dertook this great enterprize, and diſcovered
the ftraits in South America, which bear his
name. Sir Francis Drake was the firft Eng-
lifh circumnavigator, who returned from his
fucceſsful voyage round the Globe in the year
i580.
Lady L. I remember in your Sacred Hifto-
ry you mentioned the great fervices Hiram,.
king of Tyre, rendered to Solomon, when he
erected the Temple.
Ment. He furnished him with timber, con-
fifting of fir and cedar trees, from Mount Le-
banon, which he conveyed on floats to Joppa,
where they were delivered to Solomon's fer-
vants, and from thence brought to Jerufalem;
and alſo provided him with artificers of various
kinds, fkilled in working gold, filver, and in-
ferior metals, and dying fearlet, crimfon, pur-
ple, and other colours, for which the Tyrians
were
and Magnētiſm.
187
were famed. For theſe effential ſervices Hi-
ram required to be fupplied annually with
twenty thoufand meaſures of wheat, and twenty
thouſand barrels of oil for his houfhold, exclu-
five of the fame quantity of barley, wheat, wine
and oil which Solomon was to beſtow on the
workmen employed in his fervice. Thefe
were the most acceptable compenfations Hiram
could receive for the benefits he conferred on
Solomon, as Phoenicia was but a ſmall tract of
country on the fea coaft, and agriculture but
little attended to, as the inhabitants were ab-
forbed in the acquirement of riches.
Lady M. I nevertheleſs think it was be-
neath the dignity of a king, to make a bargain
for the ſupply of his table.
Ment. Solomon, exclufive of that condi-
tion, gave-Hiram, as á token of gratitude, when
the Temple and Queen's Palace were finished,
twenty cities in Galilee, which from the nature
of the foil difpleaſed Hiram; he therefore re-
fufed the proffered gift, and in contempt called
the whole land Cabul, which fignified dirty or
difpleafing, thereby intimating no one could
walk on it without being up to the ancles in
dirt. Solomon afterward rebuilt and improved
thefe
188
On Electricity
thefe cities, and planted colonies of Ifraelites in.
them.
Lady L. I hope that you have not finiſhed
your account of Tyre; is it now a place of im-
portance?
I
Ment. In confequence of the power and
eminence it obtained by the great influx of
riches, the natural effects of its extenfive coin-
merce, the inhabitants were guilty of every fpe-
cies of enormity, which attracted the Divine
diſpleaſure, and caufed a prophetic prefage of
their deſtruction to be announced, and its ful-
filment was completed by Nebuchadnezzar,.
King of Babylon. The great wealth of the
Tyrians rendered the conqueft of their country
a matter of great importance to the Babylonians,
who after a ſiege of thirteen years fubdued it,
deſtroyed the city, and put the few remaining.
inhabitants to the fword, the greater part having.
fled with their poffeflions to a new city they had
built about half a mile diftant from the ſhore:
this event happened 572 years before the Chrif
tian ara.
Lady M. I fuppofe Solomon would not
have been able to have erected the Temple, if
Hiram had not affifted him in the undertaking.
Ment.
and Magnetifm.
189
Ment. No great defign can ever be executed
without the concurrence of auxiliary co-opera-
tion; gold in the mafs, or precious ftönes in
their native ſtate, would not have embelliſhed
the facred edifice; fkill was required to form
one, and poliſh the other; and theſe combined
qualities could only be obtained by the joint ef-
forts of perfons poffeffing theſe feparate gifts.
The erection and decoration of the Temple.
were not the only advantages Solomon derived
from his connection with the Tyrians. As
the means of defraying the immenfe expences
he had incurred in the execution of his diffufive
plans and improvements, he built a great num-
ber of fhips at Ezionzeber on the coaſt of the
Red Sea, and when they were finiſhed put them
under the conduct of ſome expert Tyrian ma-
riners, who with his men fteered them to O-
phir, or the Land of Gold, near a thouſand-
years before the Chriſtian æra.
Lady L. Where is Ophir, or the Land of
Gold? I imagine many perfons refort to it.
Ment. Refpecting where it was fituated, the
learned differ in opinion; the moſt probable con-
jecture appears to be, that it was in fome part
of the Eaſt Indies, as thoſe regions abound with
the pureft gold, filver, precious ftones, ivory,
ebony.
190
On Electricity
ebony, and other curious wood, fpices, pea-
cocks, monkies, and a variety of other valuable
commodities, which greatly encreaſed the reve-
nue of Solomon's kingdom: thus the Tyrians
proved the means of this monarch eſtabliſhing
a navy, as their ſkill in navigation qualified
them for executing the vast projects Solomon's
power and riches enabled him to undertake.
Lady L. I think three years appear a greať
length of time for the fhips to be going from the
Red Sea to India, and back again.
Ment. In thoſe early agés voyages were un-
dertaken with extreme caution, and executed
with great timidity; at this period the Phoeni-
cians had no knowledge of the Polar Star, or
of the Mariner's Compafs, they were confe-
quently obliged to ſteer in fuch a ſafe courſe, as
would prevent their being expofed to the dan-
gers of the wide Ocean, as they poffeffed no
certain means to determine the diſtance they
were from the regions that were the ultimate
objects of their deftination. This circumſtance
points out the fignal benefits we derive in thefe
more enlightened times, from the perfection
attained in the Arts and Sciences, a confidera-
tion which ſhould infpire us with gratitude to
the
and Magnetifm.
191
the great fource, from whence thefe and all o-
ther mercies are obtained.
Lady M.
I am forry you have clofed your
account of the Loadſtone, as it has proved very
inſtructive and entertaining to me.
Ment. And on reflection may impart an uſe-
ful leffon, as I will fuggeft it is in your power
to have its diſtinguiſhing properties reflected and
exemplified in your own conduct and character,
and alſo in Lady Louifa's.
Lady M. How can that be poſſible? What
refemblance can there be between us who are
comparatively fo infignificant, and a ſubſtance
which poffeffes qualities of fuch inestimable
worth?
Ment. Intrinfic merit can only be appre-
ciated in the certain fphere in which it acts;
therefore if you perform the feveral duties al-
lotted you, there cannot remain a doubt but
that you will, like the Loaditone, attract the
efteem of all worthy perfons, as that mineral
operates on iron; and I truft your juft princi-
ples and difcretion will in like manner poffefs
the inclination and repellant power to reject all
unworthy purſuits; as the Magnet repulfes
Iron that is in immediate contact with it, in
direct
192
On Electricity, &c.
direct oppofition to its attractive properties:
thus you will find Virtue is a Mental Magnet,
which points as invariably to temporal felicity
and eternal reward, as the Loadſtone does to the
regions of the North Pole; and to purſue the
fimile, as the latter conducts mariners to their
deſtined port, the former will ſteer you to the
haven of celeſtial blifs!
DIALOGUE
DIALOGUE IX.
WEDNESDAY
On Meteors of the Watery kind.
THAT
Mentoria.
HAT branch of Natural Philofophy which
comprehends the various kinds of Mete-
ors, is divided into the following claffes, thofe
of Fiery, Airy, and Watery properties.
Lady L. Of what do thefe refpectively
confift?
Ment. Fiery Meteors are formed of vapours
ignited, or fet on fire, fuch as Lightning, fal-
ing Stars, and other luminous phænomena that
appear
K
194
On Meteors of
appear in the air. Airy Meteors, as Wind,
Tornadoes, Hurricanes, &c. are the effect of
the unequal temperature of the air, arifing from
the action of heat or cold.
Watery Meteers
are compofed of vapours or particles of water
variouſly modified by heat or cold, namely,
Rain, Hail, Snow and Dew. As the means of
rendering this fubject intelligible to your percep-
tions, I muſt explain the different properties of
evaporation and exhalation, which in their re-
gular proceſs occafion the production of Me-
teors.
Lady M. I will be very attentive to theſe
remarks, as thofe expreffions I am wholly un-
acquainted with.
Ment. They are diſtinct terms and of a very
different tendency. Evaporation implies the
action of difperfing or diffipating the moisture.
or humidity of a body, and Exhalation fignifies
a diſperſion of particles of a dry quality from
any maſs or ſubſtance.
Lady L. Though we fo frequently fee it.
rain and experience its benign effects, I am to-
tally ignorant of its natural caufe.
Ment. The clouds from whence rain pro-
ceeds are produced by the heat of the Sun,
whoſe attractive power draws the damp from
the
the Watery kind.
195.
the Earth, and the water from the rivers and
feas: when theſe vapours unite in the air they
form what are termed clouds, which are a com-
pound of water and air; theſe fometimes dif
perſe again, but when the aqueous particles
become fuperior to thoſe of the air, they break
through it and fall in rain, which forms diftinct
drops by the reſiſtance it meets with from the
ætherial body in falling to the Earth.
Lady M. When it rains the drops of wa-
ter appear round, what cauſes that effect?
Ment. Their globular appearance is pro-
duced by the power of attraction: for as every
particle of water of which the drop is formed
tends to a centre, every part must be equidif-
tant from that point, which confequently
makes it of a ſpherical form: from the ob-
fervations I have already made you will perceive
that the afcent of vapours confifts in a repulfive
force between the parts of matter, by which
fuch as were ſeparated from the furface of hu-
mid and other bodies, were repelled and driven
up into the air in the form of exhalations; I have
previously remarked that the denſity or weight
of the air is greateſt near the furface of the
Earth, and that its denfe quality gradually de-
creaſes as it afcends; whence it happens differ-
K 2
ent
196
On Meteors of
ent effects are produced according to the height
of their respective regions, which is occafioned.
by the various proportions of the gravity or
weight of the air.
Lady L. How different the clouds appear,
fometimes they are beautiful beyond expreffion,
at others, lowering and tremendous in their af
pect.
Ment. This effect is produced by the vari-
ous proportions of the weight of the air which
occafion the clouds to afcend in progreffive or-
der, and by reflecting the light of the Sun a-
bove and below the horizon, preſent to our
view fuch a variety of beautiful tints and ſhades as
delight the eye and excite our aftonishment:
as I have enumerated the general cauſe of rain
as produced by the concurrent effects of Air and
Water, I ſhall now proceed to point out the influ-
ence of the Winds in the production of Rain.
Lady L. I have frequently heard perfons re-
mark that it was likely we fhould have rain, as
the Wind was Southerly or Wefterly.
Ment. They had rational and philofophical
grounds for their expectation, becauſe thoſe
Winds that blow from the Ocean, as the South or
Weft Winds bring large recruits of vapours to
the clouds, and therefore are more likely to pro-
}
duce
the Watery kind.
197
duce rain than other winds which proceed from
the land or continental regions, like the North
or North Eaft Winds which generally operate to
diſperſe the vapours or diffipate the clouds.
Having thus explained the nature and properties
of Rain as to their phyfical caufes, it only re-
mains for me to delineate the proportions in
which they are difpenfed, which are the effect of
divine goodneſs; as, inſtead of being falubrious,
or beneficial, Rain would be productive of
floods, and abforb the general mafs of animal
and vegetable nature in deftruction if it came in
torrents without due intermiffion. By the dif
pofing Omniscient Power of the great Creator
of the Univerſe the general means of receiving
the bleſſing of rain conſiſts in gentle ſhowers,
or rains, that from their quantity and quality are
exacly ſuited to the important purpoſes of pro-
ducing vegetation, and fulfilling other effential re
quifites to animal exiſtence,
Lady L. I reflect with much concern that
I have never formed a proper eſtimate of this blef
fing, as I have often murmured when it rained,
if by that means I was deprived of walking or
going out in an open carriage.
Ment. This regret was occafioned by the
ftrong impulfe of your natural feelings impati-
ent under the delay of an expected enjoyment
K 3
and
198
On Meteors of
and from want of due reflection, ignorant that
your diſappointment was perhaps an univerfal
bleſſing; as rain is the harbinger of plenty,
whilst continued drought mult inevitably pro-
duce peftilence and famine;
Lady M. Pray my dear Mentoria what is
Hail, it fometimes falls in tremendous fhow-
ers?
Ment. Hail is only the drops of rain con-
gealed into ice, which is occafioned when in
their paffage through the inferior regions of the
air they meet with nitrous particles that in a
great meaſure contribute to freeze or congeal
them. In aſcertaining the properties of Hail,
it is evident it feldom hails but when the air is
heavy and the vapours
which is ufually the
afcend to a great height,
cafe in Summer time,
more frequent than in
when hail-ftorms are
Winter. In the higher regions of the air the
cold is more intenfe, and therefore it is imagin-
ed abounds with a fuperior quantity of Nitre,
which cauſes a more immediate and ſtronger
congealment of the aqueous particles, and
forms them into a body of ice of various ſizes,
their magnitude differing according to the de-
grees of cold which produced them. Theſe
icy ſubſtances acquiring confiderable weight,
defcend
the Watery kind.
199
defcend from thofe heights to the Earth in the
form of a fhower of hail.
Lady L. Hail-ftones are often of a great
fize and do much mischief.
Ment. Their fize or magnitude is in fome
degree occafioned by their acquiring a freſh ac-
ceſſion of matter in their deſcent and progreſs to
the Earth. Hail-ftones are various in dimen
fions; it is afferted there have been fome
in foreign regions as large as a turnip or Seville
orange; in our country they have been frequent-
ly found one fourth of an inch in diameter:
theſe formidable fhowers are productive of the
moſt deſtructive confequences, particularly to
vegetation of a delicate texture or infant growth;
the form of Hail-ftones is not always the
fame, they are generally conical or oblong.
Lady M. You frequently mention Nitre
as a part of the compofition of Meteors; I ima-
gined it was a medicine: explain this circum-
ftance to me ?
Ment. The Earth is formed of different
Aratums or layers of matter which by the Sun's
attractive power is diffufed through the body of
the atmoſphere for the general benefit of the
Univerfe. Thus the Air is impregnated with
different qualities, Nitrous, Sulphureous, &c.
which
K 4
200
On Meteors of
which co-operate to produce vegetation, and by
their falubrious effects, to prove univerſally be-
neficial. Nitre, which is the fubject of your
inquiry, is a falt extracted out of the Earth, a-
bundantly incorporated with the ſpirit of the
air; it is of great and general uſe in medicine,
as its cooling faline properties are very effectual
in the reduction of fevers, and a variety of other
cafes produced by an exuberance of heat.
Lady L. I am impatient to hear what Snow
is compofed of; it is a beautiful fubftance.
which I greatly admire.
Ment. Snow is produced by the vapours be
coming confiderably condenfed, yet not in fo
great a degree as to be changed into Water; in
this ſtate, by a great degree of coldness in the
upper regions of the air, the particles of the
condenſed vapour are congelated into ice; feve-
ral of them, by adhering together, compofe
fmall fleeces of a white fubftance, fomething
heavier than the air, which confequently defcend
in a flow and gentle manner through its medi-
um, being fubject by their peculiar light quality
to be driven about by the various motions of the
wind, which produce what we call drifts of
Snow.
Lady
the Watery kind.
201
Lady L. When I fee the Snow fall, I fhall
obſerve it with more pleaſure than I did before
I knew from what cauſe it was produced...
Ment. Snow, when philofophically defined,
is demonſtrated to be the natural effect that fa
line particles of every quality poffefs, to collect
together and conftitute fome ſpecific form: this
is what is called cryftalization ; therefore
Aakes of Snow are only thefe accumulated bo-
dies, which defcend to the Earth when their
weight is too great to be fuftained by the Air;
fo that Snow, when analyzed, is evidently no-
thing more than faline, aqueous particles, con-
gelated by the degrees of cold in the higher re-
gions of the Atmoſphere.
'
Lady M. I am much obliged by your giv-
ing me fo copious an account of Snow, and
entreat the favour, you will explain the qualities
of Froſt.
Ment. The converting a fluid body into a
hard folid mafs, by the influence and action of
cold, is denominated Freezing or Congelation,
which terms are appropriate to liquids when
transformed into Ice. Various are the opinions
reſpecting the natural cauſes which produce
that effect; it appears highly probable it is oc-
cafioned from an abundance of faline, nitrous
K 5
particles
202
On Meteors of
particles then abounding in the air, which pe
netrate into the porous parts of the water, and
by that means render them denſe in quality.
The effect of Congelation is uniformly attended
with the emiffion of heat; Water alfo dimi-
nifhes in weight by the procefs of its frozen
ftate, and evaporates almoſt as much as when it
was in its native fluid form, and in proportion
to the degree of cold this evaporation increaſes.
It is alfo obferved that Water that has been
boiled is more fpeedily Congelated than before
it has undergone that operation.
Lady L. Frofty weather is very agreeable,
when it is not too fevere.
Ment. This, like every other Elementary
diſpenſation, abounds with advantages, which
on a curſory view, we are not always able to
eſtimate to its due extent. In the ceconomy of
Nature, the primary object appears to be uni-
verfal benefit, which is purfued by wife mea-
fures, ordained and adminiſtered by the great
Author of Existence. The effects of Froft, like
every other means employed for the advantage
of the whole fyftem, though partially or indivi-
dually they may prove unpleaſant or deſtructive,
yet in a compound fenfe eventually operate be-
peficially. Thus you who bask in the fun-fhine
of
the Watery kind.
203
:
of Proſperity walk out on a Froſty day, and en-
joy the clearness of the Atmoſphere, warmly
clad, and fenced against the cold, and on your
return, with an appetite encreaſed by the keen-
nefs of the air, fit down to a plentiful and ele-
gant repaſt, cheared by a blazing fire and en-
livening intercourfe: reflect, that whilſt you
enjoy all theſe bleffings, many pine in want for
the common comforts and conveniences of life.
Numbers who acquire a competent fubfiftence
in the lower ranks of life, by cultivating the
Earth, working on the Water, or in other em-
ployments influenced by the weather, are by the
means of Froſt deprived of fupport, from not
being enabled to purſue their reſpective voca-
tions. How many by this circumflance can
obtain neither Food, Raiment, Fire, nor Shel-
ter? to them the ftorehoufes of plenty feem
fhut, and if it were not, that the hearts of thoſe
who poffefs abundance, did not melt in pro-
portion as the Earth and Waters freeze, a great
and valuable part of the community would pe-
rifh and be plunged into an abyfs of mifery,
The human race are not the only beings who
fuſtain a trying conflict during this ſevere yet
falutary feafon; Beafts of the Field, Birds of
the Air, Fishes, except thofe in Seas or great
K 6
Rivers,
204
On Meteors of
Rivers, Reptiles and Infects feel the force of
this congelated temperature, as their natural
refources of food in a great meaſure fail by the
influence of a long continued Froft: thus there
appears an irreſiſtible claim for liberality, when
the very Elements confpire to lock up their trea-
fures in impenetrable fecurity. Charity is the
mental folar ray which thaws the icy chains of
Poverty; Benevolence is the balm which heals
the galled wound of an afflicted heart, zealous
to acquire the neceffaries for ſupport, yet by the
rigour of the feafon deprived of the due means.
During this inclement period, various are the
appeals for aid, the calls of neceffity render the
timid bold, and felf-prefervation (which is one
of the first laws in nature) operates to induce
the ſubordinate parts of the creation to urge by
their near approach and plaintive tones, the be-
nevolent afliſtance their deſtitute ſtate requires;
under this influence the Robin-Red-Breaſt al-
moſt becomes an inmate in human habitations,
and many other inſtances might be produced of
a fimilar nature, to enforce the practice of that
philanthropy which it is my endeavour to incul-
cate.
Lady
the Watery kind.
205
Lady L. There is fo much pleaſure in rè-
lieving the diftreffed, I will never neglect any
opportunity afforded me.
Ment. I wish your charity to be diffuſive,
but not indifcriminate; as judicious benefac-
tors ſhould beſtow thofe gifts which are likely
to prove moſt ufeful to the objects of their
bounty. The circumſtances I have been enu-
merating, whenever they occur, are but fo
many opportunities to place your virtues in the
fairest light be liberal in your donations, but
not oftentatious; feek the afflicted in their moſt
obfcure and concealed receffes; obey the im-
pulfe of your feelings, which will lead you to
perform kind fervices; but above all, blend
fympathy with your alms; as many when they
beſtow gifts, by an ungracious look, or an un-
guarded harsh expreffion, eclipſe the merit of
the act, by the rigid, auftere mode of its per-
formance.
Lady M. I will ever avoid this unamiable
conduct, and in every inftance will ſtrive to
mitigate the ſufferings of the afflicted.
Ment. Philoſophy may make you Wife,
but it is Chriſtianity alone that can make you
Good; and in its divine precepts the practice
of Charity is enforced as an effential quality in
the
206
On Meteors of
the formation of a perfect character, by which
quality we are to underſtand not only the giving
of alms, but alſo that general benevolence of
heart, that is productive of univerfal philan-
throphy or good will.
Lady L. I will endeavour to regulate my
conduct by theſe and every other rule preſcribed
in the Scriptures.
Ment. An adherence to this refolution will
render you reſpectable and happy, as uniform
good conduct is fure of attaining eternal reward.
I fhall now endeavour to explain the properties
of Dew, Hoar Froft, Mifts, &c. which will
cloſe my remarks on the procefs of Freezing,
or Congelation. When the air is full of va-
pours, if a breeze arifes and checks their folu-
tion, they form clouds in the lower regions of
the atmoſphere which conftitute a miſt or fog:
this effect is ufually produced in a cold morn-
ing, and is difperfed when the Sun has rarefied
the air fufficiently to diffolve the aqueous parti-
cles, of which mift of all qualities are compofed.
From theſe obſervations it will appear evident,
that what we uſually call a Fog, is a Watery
Meteor, compoſed of grofs vapours floating
near the furface of the Earth, and is produced
by the intenſe cold quality of the air, that
prevents
the Watery kind.
207
- 1
prevents the vapours aſcending through it, which
by becoming condenſed in the lower regions of
the atmoſphere, either fall in Dews, Hoar Frofts,
or drizzling Rain, or continue fufpended in the
form of Fogs. The dimenfions of any object
viewed through the medium of a Fog appear
magnified, and in fact Fogs are only clouds of
vapour formed in the atmoſphere near to the
furface of the Earth, which render their effects
very dangerous to travellers and perfons engaged
in many particular occupations.
Lady M. I was furprized one day laſt win-
ter, that our coachman was fo much alarmed,
when he found the Fog encreaſed to a very
great degree.
Ment. He knew from experience that cau-
tion, not ſkill, would be the only probable
means of counteracting its dangerous confe-
quence. The grofs particles of which Fog is
compofed, obfcured the perception of viſible
objects; therefore he was fully aware, unleſs he
could obtain artificial light to pervade the miſty
vapour that furrounded him, he might the next
inftant be immerged in a river, or be hurled in-
to an abyſs from which no human means could
extricate him; as what we uſually call accident,
is frequently natural confequences, which might
be
208
On Meteors of
be timely avoided by vigilance and prudent cir-
cumfpection..
Lady L. Are not Fogs very unwholeſome è
Ment. The grofs quality of vapour that
forms their conſtituent parts, is in many in-
ftances too powerful and oppreffive for delicate
organs of reſpiration to contend with. I fhall
now proceed to inform you of the qualities of
Dew, which is a denfe vapour of a moiſt qua-
lity that falls on the Earth, like a kind of driz-
zling rain. The refreſhing nature of this Aque-
ous Meteor is fo well known, and its falubrious.
effects fo generally experienced, I fhall only ob-
ferve, that the Earth in fair dry weather natu
rally becomes parched by the heat of the Sun,
at which period the watery and other lefs volatile
particles, as thofe of a faline or oily quality are
by the attractive power of the Sun, raifed into
the air, and occupy thofe regions in the atmoſ
phere that are neareſt to the furface of the
Earth. Whilſt theſe exhalations are kept in a-
gitation by the folar heat, they are not viſible;
but when that heat begins to abate, a white
denfe vapour collects, which continues till by,
the genial heat of the rifing Sun in the morning
it is entirely diffipated. The effential difference
between Rain and Dew, confifts in the follow-
ing
the Watery kind.
209
ing particulars: that the condenſation of the
former is produced at a confiderable diftance.
from the Earth, and the latter is occafioned by
that effect very near to the object on which it
falls, which happens from the various opera-
tions of cold upon the vapoury air; and what
is called the Hoar or white Froft is nothing
more than the Dew changed into ice by the in-
fluence of extreme cold: black Froft differs on-
ly from this in not being attended with a miſt
or Fog, and by not appearing white.
Lady L. I have frequently perceived the
great advantages that plants of every deſcription
derive from the Dew falling on then; but I
think I recollect taking cold from wetting my
feet, by walking on grafs which was very damp,
in confequence of a great degree of Dew that
had fallen after a very hot day.
Ment. This unlucky circumftance is no ar-
gument in disfavour of the falutary influence of
Dew, the fame heat that had parched and near-
ly withered the flowers and plants, had alfo
opened the pores of your fkin; the former were
repleniſhed and recruited by the natural ſupply
of Dew, which is congenial to their generic
qualities, and in fact operates on vegetation as
food and medicine; whilft on the contrary,
your
210
On Meteors of
your temperament received a check which it
was happy proved productive of only a flight
degree of indifpofition, as thofe effects often
prove fatal to the human conftitution, which
evinces the neceffity of avoiding expofing our-
felves injudiciouſly to the fudden tranſitions of
the Elements. Thus much for the general
properties of Froft and Dew, which naturally
lead me to confider the quality of what is term-
ed Cold, that produces them in their varied ef-
fects. On ftrict inveſtigation, Cold appears to
be only a comparative term, and implies nothing
more than a lefs degree of Heat. By various
experiments it is proved that many bodies will
liquify with one degree of heat, and become
fixed or frozen with another; which is the cafe
with Metals, Salts, Oils, and Water; with one
degree of warmth the latter will appear in a fluid.
ftate, and with a lefs degree the particles will
be found to be fixed or congelated; in like
manner the vapours in a warm air are in a fluid
ſtate, and when condenſed by the cold of the
evening and defcend, they adhere to the grafs,
and affume the appearance of pearly drops, which
in that ſtate is called Dew; but thefe particles.
by the influence of a colder air become fixed,
and whilst they are floating in the Atmoſphere,
con-
the Watery kind.
211
conſtitute a rainy fog or frozen miſt which
when they deſcend fall on the grafs, fhrubs,
trees, &c. and produce a beautiful effect from the
kind of cryftaline incrustation this hoar or
white froft exhibits.
Lady M. I cannot exprefs how greatly La-
dy Louifa and myſelf are obliged by the va-
riety of information with which you ſtore our
minds.
Ment. It is my hope, and my endeavour to
render you rich in Nature's beft gifts, extenfive
knowledge and a juft fenfe of the various obliga-
tions of duty; valuable poffeffions that I would
not on your behalf exchange for all the gold
and diamonds, that Golconda and Peru pro-
duce.
Lady L. I am forry you appear to have fi-
niſhed your account of the watery Meteors.
Ment. Perhaps this definition may be in-
complete, if I do not give you fome idea of the
properties of Water in its fluid ftate. This
element poffeffes many extraordinary qualities
which would carry me beyond my preſent pur-
pofe, circumftantially to enumerate; I fhall
therefore only dwell on thoſe particulars that
may tend to give you a general fenſe of its im-
portance.
212
On Meteors of
portance. As fluidity is the effect of the influ-
ence of heat, it is afferted on philofophic
grounds that ice is the natural ſtate of Water;
by the increaſe of heat Water is rendered elaſtic
and volatile and becomes a vapour, which is
again condenſed into Water by the ſuperfluous-
heat being withdrawn. I fhall next obſerve
the effect it produces from preffure or force,.
which varies in proportion as its depth does,
without any refpect to its breadth; if it were
not for this property veffels would be forced
againſt the ſhore in their failing process, and
navigation conſequently impeded in its courfe..
It is alſo obfervable that Water always rifes to
the level of its fource, even when conveyed in
pipes or other channels: this wonderful effect
is occafioned by the preffure of the atmoſphere,
which by its general influence on all parts of
the fluid body impels it from its fource to pafs.
through any medium or vehicle till it meets with
an equal reſiſtance from the preffure of the at-
moſphere at the other end or termination: when
this preffure of the atmoſphere is removed, Wa-
ter will rife to the height of thirty fix feet,.
which is occafioned by the weight of the bo-
dy of Air on the Water's fource. It is on
theſe principles that Water-works, fountains,
and
the Watery kind.
213
and even common pumps are conftructed. Wa
ter contains a certain quantity of air, and from
its various changes produces many beneficial
effects; in their various viciffitudes we may
trace that vapours are raiſed by the Sun from
the expanſe of the Ocean by the general opera-
tions of evaporation, the effects of which are
diffuſed by the Winds through every region and
climate; when their courfe is interrupted by the
fummit of Mountains their accumulated matter
forms itſelf into clouds and defcends to the fur-
face of the Earth in the quality of Rain, Snow,
Dew, &c. The exuberant parts of theſe ex-
halations by their tendency to gravitate, bend
their courfe through Brooks and Rivulets till
they meet with Rivers, and from thence revert
to the Sea, and again are ſubject to a rotation of
the falutary confequences I have previouſly def-
cribed.
Lady M. How furpriſing thefe circumſtances
are: I am very happy I am fenfible by your kind
inftructions of their wonderful variations.
Ment. The quantity of fubterraneous Wa-
ters is incalculable; it is generally imagined
that in the fpace of the Earth's furface more
than two thirds of the Globe confift of Seas.
The diverſity of Mountains, Hills and Vallies
are
214
On Meteors of
are an eminent example of the wiſdom of God
manifefted in the creation; as, if the Earth
were perfectly level the Waters would be un-
avoidably ſtagnated, and in confequence pro-
duce feveral fatal effects. When we ſeriouſly
reflect on the beneficial properties of Water in
the general ſyſtem, it excites our gratitude and
praiſe; but when we extend our enquiry to the
individual advantages it produces to the human
race and every ſpecies of animals as well as eve-
ry branch of vegetation, we are loſt in wonder
in the contemplation of theſe tranſcendant in-
ftances of Divine Mercy. This active fluid
conduces very univerfally to the comfort and ex-
iſtence of animals of every genus; it is the me-
dium to produce the fruits of the Earth, to di-
lute food, to allay thirſt, and alſo is the genu-
ine element of a variety of animated beings
who could not live in any other ſphere: from
theſe confiderations it appears evident that Wa-
ter is an effential blefling without which we
could not fubfift, as the poffeffion of folids
would not operate to the preſervation of life un-
affifted by the happy effects derived from fluidity
in the concoction of our food, and many other
important purpoſes. Another advantage may
be
the Watery kind.
215
be fuggefted, experienced by the human race,
from the various ſprings of Water that ariſe in
the Earth, endued with medicinal virtues, oc-
cafioned by the different ftratum of the Earth
through which they pafs, fome being hot or
fulphureous, others chalybeate or of an irony or
fteel quality, and ſeveral impregnated with a
variety of nitrous and other properties, derived
from the mineral particles, of which the maſs
of Earth is compoſed.
Lady M. I have been at Bath and Tun-
bridge, and have tafted the Waters which ren-
der thoſe places ſo much reforted to.
Ment. Health is the greateft bleffing that,
as human beings, we can enjoy ; its uncertainty
and privation convinces us of its value; yet like
many other important poffeffions, it is frequent-
ly lavished by the intemperate fallies of youth,
or the depraved effects of paffions at a more ma-
ture period of life. In purſuit of this treaſure,
many who are afflicted with diſeaſes go to places
diſtinguiſhed by medicinal ſprings to feek relief,
which they often find; and I hope are duly fen-
fible of the Source or Fountain which flows
with the Streams that recruit impaired ftrength,
and tend to the prolongation of life.
Lady
216
On Meteors of
Lady L. I had no idea of the variety of
good effects we experience from Water, which
I am afraid many inconfiderate perfons do not
eftimate as they ought. I am confcious I never
afcribed to it half the confequence I now per-
ceive it poffeffes. Pray, Mentoria, do not quite
cloſe your remarks on it.
tery
Ment. As far as relates to its genuine pro-
perties, I believe I have exhauſted all the obfer-
vations neceffary for your immediate confidera-
tion, therefore ſhall cloſe my account of Wa-
Meteors; but as I ever wifh to comply.
with your requeſts, I will extend my lecture, by,
endeavouring in a kind of metaphor to fhew
you the contrary effects of Froft and Dew, ex-
emplified in the characters of Avaro and Bene-
volus, that the contraft may produce in your
mind fome forcible impreffion refpecting the op-
pofite qualities of Avarice and Philanthropy,
which bear a ſtrong fimilitude to the rigidity of
Froft and the benign effects of Dew.
Lady M. Forgive me, my dear Mentoria,
if I betray a degree of impatient anxiety for you
to begin theſe intereſting traits of human life,
which I have no doubt will have a ftrong moral
tendency.
Ment.
the Watery kind.
217
-
Ment. Avaro was of a low origin, yet by
the concurrence of fome favourable circum-
ftances, at an early period of life was eſtabliſhed
in a lucrative employ. His underſtanding was
moderate, and received no degree of cultivation
beyond the common rudiments of education,
effentially neceffary to fulfil the laborious me-
chanical duties of a commercial vocation. By
the joint efforts of perfeverance and uniform
punctuality in the general routine of buſineſs,
Avaro fucceeded in all the enterprizes he under-
took; an increaſe of wealth was the confequence
of his profperity, and in the courſe of a very
few years he became poffeffed of confiderable
property, the natural refult of unremitted affi-
duity. His conduct in his youth had been
marked with approbation, as his fuccefs was in
fome degree imputed to his merit, and in his
private domeftic concerns he adopted a rigid
economical plan, which at firſt attached to him
the character of a Prudent Man. As Avaro's
ſphere of action was circumfcribed to the ſmall
fpace of the Royal Exchange, Cuſtom-Houſe,
and Bank, his ideas were inadequate to a more
excurfive range, confequently his imagination
refpecting happineſs never foared beyond a con-
fined fituation in one of the most undefirable
རྩྭ
*
L
}
parts
2
218
On Meteors of
parts of the city, which afforded him neither light
nor air, in a degree much fuperior to what might
be obtained in a dungeon. Avaro's increaſe of
wealth ſerved no other purpoſe than to contract
his heart, and the rapid accumulations he expe-
rienced only tended to make him the more infa-
tiable in purſuit of Riches, and their confequent
concomitants, oppreffion and power. The for-
did quality of Avaro's difpofition precluded a
tafte for the convivial pleaſures of ſociety, there-
fore his habits of life were parfimonious and mi-
fanthropic. His notions of enjoyment alone
confifted in an extention of thofe poffeffions,
which when fought with unreftrained ardour,
are too often gained by means difgraceful to hu-
man nature. His rapacity kept pace with the
increaſe of his treafures, and fteeled his heart
with that kind of Apathy, which might be faid
to reſemble Froſt, as it congealed the Fountains
of Compaffion, and ſtopped the Current Tide
of every benevolent fenfation. He was Deaf to
the eloquent entreaties of haplefs innocence in
diftrefs, Blind to the oftenfible wants of the
hungry and naked, Oppreffive to his tenants,
Reproachful to the very poor to whom he refuſed
relief; and above all, was Niggardly to him-
felf, as he experienced Want in the midft of
Plenty,
the Watery kind.
219
Plenty, lived as an Alien from friendly inter-
courfe, and died unlamented by even his nearefo
relations!
Lady L. I cannot fee for what purpoſe A-
varo was fo penurious; pray what became of
his vaft poffeffions?
Ment. In defining the character of a Mifer,
we muſt conſider him as an Agent, employed
in amaffing riches that will in the end be con-
verted to their proper ufe. Avarice is one of
thoſe perverfions of human bleffings, that one
cannot contemplate without abhorrence, and
unquestionably is a difeafe of the Mind; as an
inordinate thirst for Wealth is like the eager
defire which delirious perfons feel in a raging
fever for the attainment of liquids, in a propor-
tion fuperior to what they can fwallow or en-
joy. The incitements to this vice are gradual
in their progrefs, and in the firſt inſtance ori-
ginate in the fallacious idea of ſelf-gratification;
as the Miſer aims at Riches, which according
to his principles are the fource and end of hap-
pinefs, unheedful that his Golden Harveft will
probably be reaped by an unthankful legal de-
fcendent, who will diflipate his Wealth with
the fame degree of profufion, as he has uſed of
artificial penury, to effect its amaffment. This
L 2
general
220
•On Meteors of
general confequence: Pope, thus emphatically
exprelles.
J
30
** DRO
Whò fees pale Mammon pine ainidft his ſtore,
Sees but a backward Steward for the Poor; .
This year a Reſervoir, to keep and fpare;
The next a Fountain, fpouting through his
Heir!
1
Obfervations on human life and manners bear
evident proof that Gold, when once it has ob-
tained the medium of circulation, like Water,
will always rife to the level of its fource; as
notwithſtanding it may for a ſeaſon be confign-
ed to the dreary abyfs of the Mifer's iron cheft,
by the decrees of an over-ruling Providence
contingencies happen that operate as the weight
of the atmoſphere invariably does on Water, to
bring it to its native channel, for the univerfal
benefit of the community.
Lady M. I can clearly perceive a very great
fimilitude between Avaro's character and the
qualities of Froft, as both are rendered impene-
trable to tender impreffions. How effentially
Splendidus's conduct differs from the example
of the fordid conduct you have juſt deſcribed!.
Ment.
the Watery kind.
221
Ment. Splendidus does not appear to me to
form the strong contraft I with to exhibit to
Avaro's unamiable character; profufion of ex-
pence, and apparent magnificence in the gene-
ral courſe of life, frequently rather impede than
produce generosity and benevolence of mind;
as an oftentatious difplay of riches is often ac-
companied by ſelfiſh principles, meanneſs of
fpirit, and corruption of heart; therefore I fhall
chufe the intermediate qualities which Benevo-
lus poffeffed, to exemplify the happy effects his
uniform condu& produced,, which operated like
the benignant Dew.
Lady L. My dear Mentoria, how can we
exprefs our obligations to you for thus portray-
ing the characters of Virtue and Vice in fuch
ſtrong colours, that they produce in our minds
the juft fenfations of abhorrence and eſteem!
Ment. Benevolus was defcended from an
ancient family, and refided on his paternal e-
flate, which was fituated in a Weſtern county,
at a confiderable distance from the metropolis.
In his youth he acquired a competent ſhare of
every uſeful and polite accompliſhment, uſually
attained in the regular courſe of a liberal edu-
cation; as his fortune was very large, he did
not purfue any profeffion from lucrative mo-
L 3
tives,
222
On Meteors of
tives, but as his general plan was as a citizen
of the World, to be diffufively uſeful within
his fphere of action, he ftudied Law to enable
him to affert his own rights, and to protect
thofe of others; and alfo beftowed great attention
on the Medical Art, that he might adminiſter
relief to his indigent tenants and other diftreffed.
objects in the vicinage of his domain. With
thefe laudable inclinations and ample qualifica-
tions for their difcharge, Benevolus dwelt in
the manfion inhabited by his anceflors for many
centuries, which he judiciously improved, but
preferved every veftige that remained of its ve-
nerable antiquity and as his turn of mind was
perfectly domeſtic, he married a very amiable
woman, who coincided in all the good offices.
Benevolus planned or executed, and in her pe-
culiar department fuggeſted many improvements
and falutary meaſures for the completion of
their philanthropic fyftem. As wealth is an eſ-
fential quality in the performance of munificent
acts of charity, Benevolus apportioned a cer-
tain part of his income to that laudable purpoſe,
and formed a regular arrangement for his own.
expenditure, with which he maintained a de-
gree of fplendor adequate to fupport the dignity
of
the Watery kind.
223
24
of his family, yet under fuch reftrictions as to
avoid profufion and prodigality. Under the
influence of this prudent conduct, Benevolus
became the arbiter in all difputes in the circle
of his neighbourhood; the friend and the phyſi-
cian to adminiſter relief to the difeafed in body,
or afflicted in mind; and the patron to advance
the intereſt of all who implored or required af-
fiftance. The difconfolate Widow and helplefs
Orphan found the defect of a Huſband and Fa-
ther fupplied by Benevolus's judicious bounty;
the Aged experienced in his kindneſs a ſtaff to
lean on for fupport; the Infants lifped his praiſe,
and perfons of all defcriptions and ages refound-
ed his eulogium. To theſe perfections he alſo
added a diſtinguiſhed degree of zeal for the ad-
vancement and welfare of all public inftitutions.
and improvements, to which he largely contri-
buted his pecuniary aid. In the execution of
his defigns for the general benefit of fociety, he
found employment for the idle; by his admoni-
tions and example, reclaimed the profligate, and
often by his zealous efforts effectually restored
thofe who had flagrantly wandered from the
path of duty. This philanthropic turn of mind
and genuine purity of heart, was produced by
Strict
L 4
224
On Meteors of
ſtrict adherence to the principles of Chriſtianity,
trengthened by reliance on the decrees of the
Supreme Being, which operated to conſtitute a
character that rendered Benevolus an object of
univerfal eſteem during his terreftrial probation,
and caufed his death to be a ſubject of general
regret; as his virtues were of that ſuperior qua-
lity, to entitle him to the loudeft plaudits of
Fame!
Lady L. Benevolus may with great juſtice
be compared to Dew, as he appears to have
poffeffed all thofe qualities which are the cha-
racteristic excellencies of that falutary Me-
teor.
Ment. The Chriftian charity which com-
prehends a general fyftem of moral perfection,
and was eminently confpicuous through the va-
ied fcenes of Benevolus's warfare upon Earth,
bears a literal fimilitude to the fructifying ef
fect of Dew, which is difpenfed to recruit ve-
getation in its languid drooping flate; as phi-
lanthropy enlivens the plants of adverſity, and
caufes them to fhoot with bloffoms of hope! I
cannot cloſe this account of Watery Meteors
without fubjoining fome obfervations on the
advantages which are obtained by the abforption.
of
the Watery kind.
225
of folar heat produced by the general procets of
evaporation, which conduces to the gradual
change of the temperature that in every progres-
five feaſon. we experience, and largely contri-
butes to prepare the Earth for culture, and pro-
duce the benefits derived from fertilization, and
the univerſal harmony of terreftrial bleflings.
{
}
J
L S
DIALOGUE
10.
DIALOGUE X.
THURSDAY..
On Meteors of the Fiery kind..
I
Mentoria.
{
AM now going to enter on the ſubject of
the moſt awful and ſublime effects of Divine
ſkill, exèmplified in Thunder and Lightning.
It was generally believed that this tremendous
Meteor was the natural effect of Sulphureous,
Nitrous, Spirituous, Bituminous, and Acetus or
acid particles, exhaled from various bodies which
afcended into the air, and after various fluctua-
tions by the motions of the wind, were in con-
féquence fo much agitated, that by ſtriking a-
gainſt
On Meteors of the Fiery kind.
227
gainst each other they forced themſelves through
the clouds, and by their joint action produced
the explosion which is termed Thunder, and a
flaſh denominated Lightning, the bituminous
and fulphureous occafioning the ftream of light,
and the nitrous and other qualities the tremen-
dous found, by repeated efforts or claps. of
Thunder. Modern philofophical obfervations
have at length demonftrated that Lightning is
an Electric fluid, and that fome clouds poffefs
a pofitive, and others a negative ſtate of Elec-
tricity, and the greateſt flaſhes are probably pro-
duced by the Electric fluid combining in ſome
degree with the vapoury particles of the air.
The claps of Thunder which are connected
with the flaſhes of Lightning appear to be oc-
cafioned by the filling of the great ſpace made
by the progreſs of the electric matter; as its vi-
bration, which is the fource of its found, com-
menced at the very inftant: which is evident
from the echo, or repercuffions that are heard
before the found finally reaches the ear. From
various experiments on the different properties.
of the Electric Fire, it is a probable conjecture.
that thefe variations are produced by the fer-
mentation of different particles in the atmof-
L. 6
phere,
228
On Meteors of
phere, fuch as thofe of a fulphureous and acid
quality.
Lady L. The found of Thunder is ſo terri-
fic, I tremble when I hear it; and am greatly
alarmed when it lightens.
Ment. It may not be in our power to con-
quer apprehenfion, when the fubject of our
dread is fraught with evident figns of portending
danger; yet the kind of refignation that is pro-
duced by truft in Divine Providence, keeps
thoſe ſenſations within proper bounds. In a
tremendous ſtorm of Thunder and Lightning,
no rational being can deny that the moſt fatal
confequences may accrue; but as theſe inftances.
are comparatively rare, wethould fortify our
minds by a firm reliance on the protection of
God, under whofe omnipotent direction Bolts
of Thunder and Flaſhes of Lightning purfue
their deſtined courſe. When befet with inftru-
ments of danger, it would be prefumptuous to
think ourſelves fecure; yet on the other hand
we ſhould zealously guard againſt thoſe emo-
tions, which when properly defined, are in ef-
fect a kind of finful diſtruſt.
Lady L. I will endeavour to adopt the
conduct which you inculcate with fo much e-
nergy.
Ment.
the Fiery kind.
220
f
Ment. It is not fufficient that you avoid be-
ing apprehenſive, the circumftances of this aw-
ful predicament require alfo that you ſhould
expreſs gratitude for the protection you experi-
ence during this general convulfion of the Ele-
ments; as objects of greater magnitude and
importance are often deftroyed, whilft you have
eſcaped the dire effects exhibited in a tremen-
dous ſtorm, which is the entire effect of Divine
mercy, not of your fuperior merit.
1
Lady M. Pray, my dear Mentoria, favour
us with fome further particulars of the proper-
ties of Thunder and Lightning. What is a
Thunder Bolt?
་
Ment. It is a fubftance confifting of a com-
pact undiffolved body of ignited matter, which
had not time to explode in the air, but is darted
with the velocity of light itſelf, to the objects
on the ſurface of the Earth, and acts with irre-.
fiftible force; its fatal effects are manifeftéd by
the deſtruction of trees, buildings, and everý
other ſubſtance (even thoſe of the fſtrongeſt tex-
ture) that obftruct its progrefs..
Lady L. Lightning is not always deftruc-
tive; and does it not frequently appear unat-
tended by alarming ſymptoms?
Ment
230
On Meteors of
Ment. The Electric matter of which Lightning.
is compofed, may be divided into three diſtinct
claffes the firſt is that in which it fimply ex-
plodes and flaſhes, in a degree of force infuffi-
cient to be deftructive; the ſecond is when it
explodes with greater force, or denfity, which-
often operates to ftrike perfons blind, or fet va-
rious objects on fire; the third and laſt ſtage is
that of the Thunder Bolt, which is the moſt
awful ſtate of this wonderful phænomenon.
From the obfervations I have already made, you
will perceive that Thunder is probably produced
by a fudden kindling of combuftible exhalations
in the clouds, and Lightning is nothing more
than the Fire bursting from thofe clouds this
opinion is confirmed in a great degree by forms
of Thunder and Lightning, being moſt fre-.
quent in fultry weather, when the air is more
ftrongly impregnated with fulphureous and o-
ther combustible particles. With all due ref-
pect to modern experiments and opinions, from
juſt deference to Sir Ifaac Newton's theory of
optics, I fhall inform you that he defined
Lightning in the Heavens as analogous to the
flaſhing of Gunpowder in an unconfined flate
or condition, and that Thunder produced a fi-
$
:
milar
the Fiery kind.
231
7
milar effect to the report of a Gun, from the
powder kindled but confined in the barrel.
Lady M. I recollect feeing Iron conduc-
tors put on houſes and other buildings, as the
means of preventing fatal accidents from Light-
ning; how can they operate ſo beneficially?
Ment. The Fire of Lightning is Electrical,
therefore can be attracted by non-electric bo-
dies, fuch as Iron, Earth, &c. fo that theſe
conductors are intended to prevent general bad
effects, by the antidote of a partial attraction.
Lady L. Is not Lightning invariably ſeen
before the Thunder is heard?
Ment. Undoubtedly, and always in a me-
dium of proportion to the diſtance of the Thun-
der clouds; as Light travels with a greater de-
gree of velocity than Sound.-
Lady M. In what refpect does Thunder
prove beneficial?
Ment. By altering the ftate of the air, and
by an exploſive effort difperfing thoſe particles
which might prove of a hurtful tendency, if
they remained floating in the atmoſphere. Air,
like Water in a ſtagnate ſtate, would be pro-
ductive of difeafes and fcarcity, originating
from its putrid tendency; this dire effect is
happily counteracted by Winds, Thunder,
Light-
232
On Meteors of
Lightning, and other Meteors which operate
to purify the regions of the air, and conduce to
the general harmony of the feafons.
Lady L. I will forbear in future repining
when it Thunders, as I clearly perceive it is
attended, with general benefit to fociety.
Ment In treating of Meteors I muft not-
omit mentioning Falling Stars, which are alfo
vapours kindled in the Air, often very near to`
the furface of the Earth, and fometimes in the
higher regions of the atmoſphere: many are of
opinion theſe, like other fiery meteors, are pure
Electric matter.
Lady M. In fome of your former inftruc-
tions I remember you mentioned a Meteor
called Ignis Fatuus, commonly termed Will
with a Wifp, or Jack with a Lantern.
Ment. It was a fubject of general belief,
that theſe luminous vapours frequently aroſe in
marshes, and other damp fituations, forming a
Meteor reſembling the flame of a candle, which
frequently miſled travellers; but at preſent there
are doubts entertained whether theſe effects were
not more the conſequence of a deluded imagina-
tion, than a circumftance exifting in nature.
The real quality of this exhalation is defined to
be an ignited vapour produced by the decompofi-
1
tion
the Fiery kind.
233
tion of vegetable fubftances in low marshy fitua-
tions, or bogs, that from the inflammable air
with which they abound, caufe a luminous ap-
pearance, and by wafting near the ſurface of
the Earth, create alarm and apprehenſive fenfa-
tions in fuperftitious uninformed minds, and
confequently attach the idea of this phænome-
non being the effect of fupernatural cauſes.
Theſe Meteors are fometimes feen in different
numbers on the fame ſpot, and by interſecting
each others paths with great rapidity, they fre-
quently disappear all at once, which is probably
occafioned by their meeting with ſome object in
their progrefs, which obftruct's their courfe.
Lady L. Thofe muſt be very weak perfons
who are frightened when theſe Meteors ap-
pear.
Ment. Prejudices are conveyed by the igno-
rant, and implicitly received by thoſe who are
immediately connected with them, by the rela-
tive ties of kindred or friendly affociation; this
medium is the native fource of the propagation
of error which takes deep root in underſtandings.
that are not within the fphere of receiving ge-
nuine information.
Lady
234
On Meteors of
Lady L. I have frequently feen the Aurora
Borealis, Streamers, or Northern Lights, are
they Meteors?
Ment. Without doubt, and of the Fiery
kind, as they have a luminous appearance,
which is fometimes visible at night in the
Northern part of the heavens, and is almoſt con-
ſtantly perceptible in the regions near the North
Pole; its natural caufes have not hitherto been
decifively afcertained, though it is almoſt uni-
verfally allowed that this Phænomenon is folely
produced by Electric light.
Lady M. I fear that you have finiſhed your
account of Meteors, which I much regret.
Ment. As I have fo fully deſcribed thoſe
of the Watery and Fiery kinds, there only re-
mains the Airy clafs to be confidered, the pro-
perties of which I explained in the regular
courſe of my definition on Air; therefore I
fhall only add a few general obfervations reſ-
pecting the benefits that are derived from the
variations of the Winds. In a commercial
country like Great Britain, the fluctuations of
the Air, which comprehend the various Me-
teors denominated Winds, are productive of
many fubftantial advantages; as they cannot
blow from any point, without wafting to our
fhores -
the Fiery kind.
235
hores the productions of the moſt diſtant
climes.
Lady L. I am convinced of the advantages
'you have enumerated; yet 1 fhould always like
the Wind to be calm.
Ment. Before we ſeriouſly form fuch a
wifh, we fhould duly confider the probable
confequences of a tranquil ſtate of the air. If
there were a general calm, the Winds would
undergo but flight variations in the body of the
atmoſphere, which would produce the moſt fa-
tal effects; veffels would be flow in their pro-
grefs, and the general purpoſes of trade and na-
vigation confiderably impeded. After having
thus amply confidered the different properties of
Watery, Fiery, and Airy Meteors, and their
natural cauſes, there appears no branch remain-
ing that claims attention, except the general
qualities of Fire, which I will endeavour to ex-
plain.
Lady L. I wish to hear an account of this
Element, as it produces many great and won-
derful effects.
Ment. The real nature of Fire has been the
fubject of difpute with naturalifts and philofo-
phers; ſome maintain the opinion it arifes
from a violent motion of the parts of any body
or
236
On Meteors of
or fubftance, whilft others affert it is a fluid pof
feffed of certain qualities diftinct from every
other the latter feems to be the ſyſtem beft ap-
proved, and moſt generally received.
:
By the
term Fire, I with you to underſtand that won-
derful fubtile agent of nature, which by fome
inviſible caufe, expands bodies, and renders
them hot to the touch, by the effects of which
fluids are rarefied and changed into vapour, and
in the end evaporate, or terminate, by being
melted into glafs. From various experiments
it is evident that Fire exifts and acts unconne&ed
with matter, independent of every terreftrial
fubilance, neither being produced nor com-
pounded with any thing of which we have any
knowledge or perception. The action of Fire
is proved by a number of ingenious experiments,
as well as by the common confequences we per-
ceive; and from an inveſtigation of folar light,
a certain modification of that quality is moft
likely the primary caufe of heat, expanfion, va-
pour, &c. as it in every refpect anfwers to the
characteriſtic properties of Fire; and it is
thought highly probable that the Electric mat-
ter is in effect nothing more than the ſolar heat
abforbed by the Earth, and by thus undergoing
fome tranſmutations effentially differing from its
}
appear.
the Fiery kind.
237
appearance when acting as Light, therefore the
affinity between Fire, Light and Electricity arè
by many identified as one ſubſtance.
Lady M. I am happy to hear fome rational;
account of Fire, as though I daily experience
the comforts arifing from this element, I am
ignorant of their philofophical cauſe.
{
Ment. The elementary fluid of Fire is
univerfally difperfed in almoſt every part of
the Creation, and it is generally afferted that
Fire or Heat is the only permanent elaftic fub-
ſtance in Nature: Air is its natural food, which.
produces, ignition or the kindling quality; for,
by uniting with combuftible matter ſuch as
coals, wood, &c. &c. in infinite variety, the
Air is deſtroyed and the fire that conftituted its
elafticity is confequently emitted; this effect is
demonſtrated by combustibles not burning when
excluded from Air...
•
Lady M. I fhall now have a clear idea of
what cauſes the Fire to burn which blazes in
Winter to infufè warmth into us at that dreary
feafon.
Ment. It is a common but vulgar error to
imagine that flame is the quality poffeffed of
a greater degree of heat than the other parts of
Fire: its properties have been defined by Sir
Ifaac
238
On Meteors of
Ifaac Newton to be a burning ſmoke which has
not the fame degree of intenſe heat as the com-
bustible body from which it proceeds, only by
aſcending and diffuſing itſelf, confequently com-
municates Fire to a greater extent than its ori-
ginal fource; this is the caufe of the devafta-
tion produced by conflagrations, which often
rage with ſuch violence as not to be eaſily ex-
tinguiſhed by the ſtrongeſt efforts of human
ſkill.
Lady L. I have heard of the tremendous
confequences of Fire, which I dread when I
am in London or any populous fituation.
Ment. Fire like the other elements, is be-
neficial in its operation, yet in its extreme ef-
fects proves deftructive; in like manner Water
may produce inundations, Air hurricanes and
tempefts, and the Earth a general convulfion of
Nature. With gratitude we muſt reflect that the
good we enjoy greatly preponderates in the ſcale
of human allotments when weighed in the balance
againſt the evil which is placed in the oppoſite
medium; in proof of this felf evident principle
I will endeavour to enumerate the benefits de-
rived from Fire in the general economy of the
Univerſe. As inhabitants of this terreſtrial
Globe we are peculiarly indebted to Providence
for
the Fiery kind.
239
-
for the difpenfation of Fire; if it were not for the
cheering influence of this element nearly half
our time would be obfcured by the gloomy ef
fects of darkneſs and the painful fenfations of in-
tenſe cold; our food could not be duly prepar-
ed, and confequently not maſticated in a degree
fuited to our powers of digeftion. Minerals
and metals would be of no effential uſe, as with
out Fire they could not go through the various
chymical proceffes which render them eventual-
ly of diffufive utility in arts, manufactures
and commerce; it is therefore to the general
beneficial effects of Fire that we may afcribe
moſt of the bleffings we daily enjoy; even gold
would not anſwer the important purpoſe of pro-
curing the commodities neceffary for our exiftence
till purified by Fire; as, by its confequent fufion it
is converted into coin and becomes the principa!
agent of wealth by adminiſtering all thoſe qua-
lities on which human accommodation ſeems
to depend. Thus much for the univerſal influ-
ence of Fire which enlivens the general fyftem,
and operates to produce comfort to individuals.
of every rank and clafs: the Fire that burns in
the cottage of a Peaſant diffuſes warmth with
as much ardor as that which blazes in the
pa-
lace
240
On Meteors of
lace of a Monarch: the taper that illuminates
the Mechanic ſheds as bright a flame as that
which cheers the most renowned Potentate,
there being no gradation in the diffuſion of this
bleſſing in its genuine quality, all ſtand in need
of its aid to render fubfiftence replete with en-
joyments and permanent; therefore it is wifely
ordained its influence fhould be univerfal.
Lady M. In Winter I fhall now more
forcibly be fenfible of the advantages of Light and
Heat: I will be ingenuous enough to confefs
I never reflected by what means they were ob-
tained, neither did I gratefully acknowledge
the benefits I derived from them.
Ment. If it were poffible to tranfport you to
Lapland or Kamtfchatka, you would then experi-
ence a degree of cold that would excite compa-
rative fenfations of regret when you reflected
on the more temperate regions you had left;
this like other inftances requires the experience
of contrary effects to render a perfon duly fen-
fible of imparted bleffings. As your wants are
liberally fupplied, abundance precludes an expe-
rimental perception of penury, and in all other
cafes your profperity prevents your being ex-
poſed to thoſe exigences which bring conviction
to
the Fery kind.
241
to the teſt; I fhall therefore conclude with ex-
preffing my ardent wiſhes that you may ever
poffefs a due proportion of every elementary
bleffing, for which I moft earnestly exhort you
to inwardly feel, and exteriorly demonftrate
uniform gratitude, and every other ebullition of
moral virtue,
Y
M
DIALOGUE
}
DIALOGUE XI.
FRIDAY.
On the Phænomena Halo, Parhe-
lion, and Rainbow.
1
Mentoria.
I
Shall request you will beſtow great atten-
tion on the curious Phenomena I am going
to defcribe, denominated Halo or Crown, Par-
helion or Parhelium, or Mock Sun. Thefe won-
derful appearances are cauſed by the reflection
and refraction of Light. The Halo or Crown
is frequently viſible, confequently excites no fen-
fations of furpriſe or aftoniſhment ; but the Par-
helion from its rare appearance is regarded by
the
On the Phanomena Halo, &c.
243
1
the common people as a prefage of fome extra-
ordinary event. The Corona or Halo is a lu-
minous circle furrounding the Sun, Moon, the
Planets, and fixed Stars. Thefe circles are
fometimes white, and at other times coloured
like the Rainbow: it often happens that only
one is vifible, and at other periods feveral con-
centric Coronas make their appearance at the
fame time. Thoſe which have been obſerved
about Sirius and Jupiter never exceeded three,
four, or five degrees in diameter; thofe which
furround the Moon are alfo fometimes of fimi-
lar dimenſions, but they, as well as thofe
which furround the Sun, differ in magnitude :
their diameters alfo differ very effentially during
the time of obfervation, and the breadth of the
coloured and white circles vary very much, viz.
from two, three, four, to feven degrees. The
colours of theſe Coronas are alſo more foftened
or lefs vivid than thoſe of the Rainbow, and are
arranged in a different manner according to their
fize. Thoſe which were obferved by Sir Ifaac
Newton in 1692 were claffed in the following
order, beginning from the interior part in the
first or innermost part were Blue, White and
Red in the middle were Purple, Blue, Green,
ጎ
:
Yellow and pale Red; in the outermoft pale
M 2
Blue
244
On the Phænomena Halo, c.
.
Blue and pale Red: thefe Coronas are very fre-
}
quent in Holland. M. Mufchenbroeck afferts
fifty may be feen in the day time alinoſt every
year; but it is very difficult to difcern them, ex-
cept the eye is fo fituated that not only the body
of the Sun but alfo the neighbouring part of
the Heavens can be ſeen. In North America
they are fo common that there are uſually one
or two furrounds the Sun every week, and the
fame number about the Moon every Month.
Halos round the Sun are alfo very common in
Ruffia; it is afferted that in the year 1758
twenty-fix were perceptible from the month of
April to September. Defcartes has obferved
it never rains when this Phænomenon appears,
from which he concludes it is occafioned by the
refraction of the light in the round particles of
ice which are then floating in the atmoſphere;
and though thefe particles are flat when they
fall to the ground, hé imagines they muſt be
protuberant in the middle before their defcent,
and in proportion to that projection he ſuppoſes
that the diameter of the Halo would vary.
Lady L. I never heard of thefe things be-
fore, and am much furpriſed at their exiſtence in
the works of Nature.
Ment. You are perhaps a firanger to the
philofophic
On the Phanomena Halo, &c. 245
philofophic terms that defcribe thefe Phænome-
na; though I make no doubt you have frequently
feen the Halos which furround the Moon, and
have heard people exprefs their expectations of
change of weather from a burr appearing round
that Planet, which was identically one of the
Halos or Coronas I have been defcribing.
Lady L. Whenever thefe appear, I fhall ob-
ferve them with great attention, and will in-
form all my young friends of theſe extraordina
ry circumſtances..
Ment. Perhaps you may
Perhaps you may extend your infor-
mation beyond the limits of youth, as I am
fearful too many at a more mature period of life
are ignorant of thefe-wonderful inftances of cu-
rious Phænomena, that you muſt recollect are on-
ly visible in frofty, misty or hazy weather,
which caufes them to be regarded as the harbin-
gers of rain. There is an artificial mode of re-
preſenting theſe Halos or Coronas by placing
the flame of a candle in the midst of a team in
cold weather, or elſe at the diſtance of fome
feet on the other fide of the window, which
will caufe the flame to be encompaffed by a co-
loured Halo; this effect may alfo be perceived
when the window in the room is encrufted with
a thin body of ice, through the medium of which
M 3
the
246 On the Phanomena Halo, c
the Moon will appear with a large Halo of Tex
veral varied tints.
}
11
Lady L. I fhall be impatient for the kind
of weather that you defcribe as neceffary.
to make this experiment, when I fhall with
much pleaſure bring all your obfervations on
this fubject to the proof.
Ment. The next fubject to be confidered is
the Parhelion, Parhelium, or Mock Sun, which
appearance is extremely curious. This Meteor
is exhibited in the form of a very bright light
appearing on one fide of the Sun, it is appa-
rently of the fame fize of the luminary it re-
prefents, though not always equally bright nor
even of the fame fhape, and when a number
appear at one time, they vary in magnitude,
and luftre. In their exterior parts they are
tinged with colours like the Rainbow, and
many of them have a long fiery tail oppoſite to
the Sun, but of a paler or fainter hue towards.
the extremity. Parhelia are ufually accompa-
nied with Coronas, fome of which are white
and others tinged with the colours found in the
Rainbow: they differ effentially in number and
dimenfions, but uniformly agree in breadth,
which is the fame as the apparent diameter of
the Sun. A very large circle parallel to the ho-
1
rizon
On the Phenomena Halo, &c. 24%
rizon paffes through all the Parhelia, which if
it were entire would go through the centre of
the Sun frequently there are arcs of leffer
circles concentric to this touching thoſe colour-
ed circles which furround the Sun, theſe are
tinged with colours and contain other Parhelia:
the order of the colours in thefe circles refem-
ble thofe of the Rainbow, but in the interior
part with refpect to the Sun they are Red,
which effect is alfo obfervable in many other
Coronas, Sometimes the Sun has rifen or fet
with a luminous tail projecting from him of the
fame breadth with his diameter, and perpendi-
cular to the Horizon,
Lady M. I am amazed at thefe circum-
ftances; I fhould be much furpriſed if I were
to fee this Mock Sun,
TY
Ment. This effect is probably produced from
the infinitude of fmall particles of ice floating
in the air, which multiply the image of the Sun
either by refracting or breaking his rays, and
thus caufing him to appear where he is not, or
by reflection reprefenting his form, as objects
are feen in a looking-glafs.
Lady M. I wonder who firft obferved theſe
Phænomena.
M4
Ment.
241
On the Phenomena Halo, &c.
!
Ment. Appearances of this kind have been
mentioned both by ancient and modern Phi-
lofophers; Ariftotle obferves they are only
difcernible when the Sun is very near the Hori-
zon, though he ſpecifies two that were feen in
Bofphorus from morning till evening. Pliny
allo has recorded the period when this Phæno-
mena appeared in Rome. In more modern
times the Parhelia were viſible in Rome A. D.
1629, at which time four were diftinctly ob-
ferved; fome were alfo obferved 1683. In Eng-
land and Scotland two have frequently been
feen at a time. Parhelia have been difcernible
for one, two, three and four hours, and in
North America where they are frequently vifi-
ble they are often feen from Sun-rife to Sun-fet,
when they diſappear: it fometimes rains, or
there are falls of fnow of an oblong form, which
is occafioned from the Air in North America
abounding with frozen particles in the form of
fpiculæ, that are perceptible to the naked eye,.
and are probably the caufe of Coronas and Par-
helia. Sometimes it happens that the Parhelia
appear in a different manner; as when three
Suns have been perceived in the fame vertical
circle, well defined and touching one another;^
the true Sun was in the middle, the loweſt
touched
On the Phenomena Halo, c. 249
touched the Horizon, and they fet one after ano-
ther; a fourth Parhelion has alfo appeared di-
rectly under the real Sun, but this effect is very
uncommon.
2002
J
Lady M. I am fearful you have clofed your
account of the Parhelia, which I regret as it
is a fubject entirely new to me.
Ment. Novelty, which confifts in the conf-
deration of ſubjects unexplored by common
obfervers, is peculiarly attached to the feafon of
youth: every year, nay, every month, week
or day developes fome branch of knowledge,
and by thus extending your information quick-
ens the defire for frefh attainments. Though
I have finished my account of the Parhelion or
Mock Sun, I must add fome remarks on an ex-
traordinary. Phænomena that have been obferved
called Parafclence or Mock Moons: thefe won-
derful meteors are accompanied by tails and co-
loured circles like thofe which are perceived in
the Parhelia: an account of ſeveral and a par-
ticular defcription of a fine appearance of this
kind may be found in the obfervations of Muf
chenbroeck.
A
Lady L. I fhall in time ceafe to wonder.;
as every fresh inftance of information that I re-
ceive increaſes in furprifing caufes and effects.
M5
Ment,
250
On the Planomena Halo, &c.
but
Ment. Aftonishment, or what we ufually
call wonder, is the natural effect of ignorance;
the well informed rarely meet with objects and
very
few occurrences or circumftances to ex-
cite furprife. The works of Nature are fo dif-
fufive, and many of their operations fo pro-
found and occult, it is fcarcely poffible for an in-
dividual to attain a complete knowledge of eve-
ry particular quality or perfection, yet a moder-
ate degree of application will furniſh a mind re-
plete with acute perceptions and due reflection
with a competent fhare of learning on moft.
philofophic fubjects; if we avoid perplexing
our ideas with intricate theories and abftrufe
points of ſcience, which often tend to obfcure the
truth and obſtruct the paths of valuable infor-
mation.
Lady L. I am convinced, my dear Mentoria,.
you will fhield us from this error, as the infor
mation you impart cannot fail to enlarge our
ideas.
Ment. It is my principal aim to accompliſh
this defirable purpoſe, I therefore endeavour to
exprefs myſelf in terms that are upon a level with
your conceptions: It is reported that thể Of-
trich can digeft iron, but as I fear your intel-
lectual powers are not of an equal ftrong tex-
ture,
On the Phænomena Halo, c. 251
}
ture, I render your mental fuftenance adequate
to your concoctive faculties. Technical terms,
ſcientific expreffions, and philofophical proceffes
are extremely uſeful and indifpenfibly neceffary
for the propagation of knowledge; yet their ge-
neral adoption and familiar ufe would render a
female, particularly one of tender years, ſubject
to the reproachful epithet of pedantic, or rank
her as a ſmatterer in learning. From thefe ob-
fervations it will appear evident, that I wiſh your
knowledge to be genuine; but your expreſſions
fimple, that is, unmixed with an oftentatious
difplay of learning, and uncorrupted by an ex-
uberance of ornament, and an apparent defire
to acquire an oppreffive degree of fuperio-
rity.
Lady M. There is little danger of my er-
ring in that point; as when I am in company
I have not courage to give my opinion, and
I perceive the fame fenfations in Lady Lou-
ifa.
Ment. Courage, or that quality which in the
general intercourfe with fociety is in fome de-
gree neceffary, may with more propriety be
termed proper confidence. Too great a portion
of timidity, or what we uſually call baſhfulneſs,
obfcures merit, as it prevents the due exercife
M 6
of
252
On the Phænomena Halo, &c.
of thofe powers and accomplishments which are
an honor to human nature.
To this falle qua-
lity we may afcribe the errors of moſt young
perfons in common behaviour, and alfo the im-
perfect performance of whatever they undertake
to execute in company: as the means of over-
coming this evil, from the earlieſt, age, children
fhould be accuſtomed to fing, dance, and per-``
form all other parts of their education, even
though their attainments in thoſe reſpective
branches are incomplete, by which means they
acquire an eafy unembarraffed manner, that adds
great grace and dignity to their general deport-
ment. I have been thus particular on this fub-
ject, as I earneſtly hope that you will obferve the
due medium between a bold forward addreſs,
and an infignificant fneaking behaviour, as they
both will deſtroy every fenfation of reſpect or
confequence.
Lady M. What will be the next fubject on
which you will be kind enough to expatiate?
Ment. The Rainbow or Iris, which is one
of the moſt beautiful objects that nature exhi-
bits.
Lady L. I always admire the Rainbow, as
the colours, though they are brilliantly gay, are
fo
On the Phanomena Halo, &c.
253
to fkillfully blended, there appears not the leaft
degree of glare.
Ment. This is evidently the triumph of na
ture over art, the greateſt effort of human taſte"-
or fancy could not compact fuch a variety of
tints without producing an effect that would
weary the eye and offend a correct taſte. An
affemblage of varied hues fuch as the Rainbow
preſents, if arranged by an artiſt poffeffed of ſu-
perior excellence in his profeffion, would be con-
fidered as a compoſition incongruous in its ar-
rangement; yet by the plaſtic power of Nature,
all the component parts fo well accord they
form a regular harmonic effect, the lights and
ſhades are fo gradually contraſted, that brillian-
cy and fplendour are produced, and the mind
ftruck with the impreffion of perfect beauty.
Having thus confidered the general effects of the
Rainbow or Iris, I fhall proceed to explain its
natural cauſe.
Lady L. I wish to be informed by what
means the Rainbow is produced?
کے
Ment. When a cloud converted into Rain,
is expoſed to the rays of the Sun, and the eye
of the perſon who views it is between the Sun
and the Cloud, the Rainbow is clearly perceptio
ble.
Lady
254
On the Phænomena Halo, &c.
}
Lady M. I can clearly diſtinguiſh every kind
of colour, red, orange, yellow, green, blue;
indigo, and violet.
Ment. Thefe beautiful tints are occafioned
by the refraction of the rays of light that paſs
through the Rain, which fills the atmoſphere at
that period. The uppermoft drops reflect the
red rays, the next in degree is the orange, and
fo on in regular gradation, the violet being the
laft that appears.
Lady L. Are there any particular periods
when the Rainbow is difcernible?
3
Ment. The Sun cannot poffibly be more
than 42 degrees above the horizon when a Rain-
bow appears; becauſe when it is higher than
that point, its axis paffes beyond the eye of the
fpectator. The different dimenfions of the
Rainbow entirely depend upon the height of
the Sun at that period; when the Sun is in the
Meridian, the Rainbow appears the leaft to us,
and as he gets gradually lower and lower, the
Rainbow increaſes in height; and when the
Sun is in the horizon, the Rainbow attains its
greateſt dimenſion, and appears nearly of a ſe-
micircular form. The Rainbow always is vifi-
ble in that part of the heavens apparently oppo-
fite to the Sun, from which it appears evident
that
On the Phænomena Halo, &c. 255
that it is occafioned by the Solar rays falling on
the drops of Rain.
Lady L. I recolle& frequently perceiving a
fainter kind of Rainbow in the ſky; by what
means is that phænomenon produced?
Ment. This fainter coloured Bow that ap-
pears above the Rainbow, is commonly termed
a Water Gall, and as the colours are reverfed in
pofition and effect, it is undoubtedly a fpecics
of reflection from the Rainbow, and as a confi-
derable portion of light is loft in each reflection,
the colours in the higher Bow, as a natural
confequence, become more diluted or foftened
than thofe in the lower, from which they are
derived.
Lady M. I am more obliged than I can ex-
prefs, by your explicit defcription of the Rain-
· bow.
Ment. You muſt keep in mind that the
Rainbow never appears but when it rains, or
nearly at that period, and you may ſimplify its
philofophical effects by an eaſy experiment, as
a bubble at the end of a pipe will refract the
Sun's light in the fame manner as the drops of
Rain which form an Iris or Rainbow, in both
cafes the gradation of colours is uniform. An
artificial fountain alfo will exhibit, in form and
colour,
255 On the Phænomena Halo, &c.
*
colcur, the exact properties of this extraordinary
phænomenon, and from the peculiar conítrac-
tion of our vifual organs, the dimenfions.
though 'fo near, will appear as far off, and as
large in fize, as the real Rainbow.
Lady L. I fcarcely know any object in Na-
fure more beautiful than the colours of the
Rainbow.
Ment. Its form is equally worthy of admi-
ration, as there is ſomething inexpreffibly grace-
ful and majeſtic in the femicircular figure in
which this phænomenon generally appears, in
the vaulted concave of the Celeſtial Hemif-
phere.
Lady M. Is not the Rainbow particularly
mentioned in the Bible?
Ment. For a full explanation of this ſub-
ject, it may be neceſſary to revert to the account
I gave you of the Noahchical difpenfation of
the Covenant of Grace which God entered into
with mankind, immediately after the Flood.
The Supreme Being, when he had enjoined.cer-
tain conditions of obedience, affured Noah of
profperity and his bleffing; and in token. that
the Earth ſhould not again be deſtroyed by a
Deluge, thus declared, "I do fet my Bow in
the Cloud, and it fhall be a Covenant between
me
On the Phanomena Halo, &c.
257
}
me and the Earth, and it fhall come to paſs,
when I bring a cloud over the Earth, that the
bow fhall be ſeen in the cloud, and I will re-
member my covenant, which is between me,
and you, and every living creature of all flefh,
and the waters fhall no more become a flood to
deſtroy all fleſh, and the bow fhall be in the
cloud, and I will look upon it, that I may re-
member the everlasting covenant between God-
and every living creature of all freſh that is upon
the Earth. And God faid unto Noah, this is
the token of the covenant which I have eſta-
bliſhed between me and all fleſh that is upon the
Earth." Thus graciously did God indemnify
the inhabitants of the Earth from experiencing
his wrath, by the fame means as before had ex-
preffed his difpleaſure: therefore we ought to
regard this inftance of Divine condefcenfion
with the moſt reverential gratitude.
Lady L. I always thought the Rainbow a
very pleaſing ſpectacle, but had no idea of its
ferious import.
Mint. You will perceive in a variety of other
inftances, your perceptions have been able only
in a very limited degree to appreciate the im-
portance of objects to the extent of their intrin
fic worth, or latent tendency. The contem-
plation
258
On the Phenomena Halo, &a
plation of the works of Nature leads in an efpe-
cial manner to enlarge the conceptions, wher
we reflect that God is ever preſent, our actions
fhould be guided by the ftricteft rules of circum-
fpection; and when we feriously confider his
infinite attributes are not confined by fpace, nor
his exiſtence or duration circumfcribed by time,.
our imaginations naturally foar to the boundleſs
ages of eternity. The Firmament, and the
various luminaries that adorn it, which are pro-
bably diſtinct worlds, all co-operate to impreſs
the mind with the moft fublime and awful fen--
timents; and in this reſearch our intellectual
powers are abforbed in wonder; and when ex-
erted to their greateſt ſtretch, cannot fully com
prehend the heights of omnipotent perfection !
{ A
DIALOGUÉ
*
}
}
DIALOGUE XII.
>
!
SATURDAY
On the Terraqueous Globe, various
kinds of Earth, Foffils, and
precious Stones.
}
Mentoria.
IN the courfe of my Lectures on Aftronomy
and Natural Philofophy, I have hitherto
only deſcribed the Earth as a Planet annually re-
volving round the Sun, as a part of the Solar
fyftem; I fhall therefore now endeavour to enu-
merate, its properties and perfections, as the
Terraqueous Globe, which is affigned to us
as a temporary abode, in our prefent probation-
ary ftate.
Lady
260
,
On the Terraqueous Globe, છે.
&eLady Louifa. I think that will be a fubject
replete with many interefting and important
particulars.
Ment. We must first confider the Earth as a
large mafs or body, of a Spheroid form, rather
flatted at the Poles, and more protuberant at its
equatorial parts, the furface of which is divided
from one Pole to the other by two bands of
Earth, and two of Water, of immenfe magni-
tude and dimenſions. As navigators have not
been able to penetrate to regions at the Poles,
from the ice in thofe feas, the proportion of
Earth and Water cannot be precifely aſcertain-
:
ed only from what is difcovered, it is generally
believed there is more fea than land. As it is
my intent that my prefent inftructions fhould
be rather Philofophical than Geographical, I
fhall not specify the different kingdoms and
countries on the Earth, but confine myſelf to a
definition of its conftituent parts, and fhall af-
fix a Copper-Plate of the Globe, which will
enable you to judge of its conftruction refpect-
ing its Terreftrial and Aquatic properties.
Lady Mary. I thall be very attentive to your
obfervations, from which I have no doubt Lady
Louifa and myſelf will reap folid advantage.
Ment
On the Terraqueous Globe, &c. 26T
Ment. I fhall firft confider the Univerfal
power, energy, or fpirit that is to be regarded
as the Divine agent or efficient principle by
which the whole mafs of matter in the Earth is
actuated, agitated, or put into constant motion;
this evidently exifts, and is demonftrated, by
every object in Nature; as if there were no mo-
tion, there could be no heat, of which there
is a confiderable portion in the Earth, unquef
tionably proved by the wonderful Phænomena
of Hot Springs, Volcanoes, &c.
Lady L. I am amazed at theſe inftances of
Divine fkill, exemplified even in the Earth, on
which I never beftowed a thought.
Ment. The next point to be explained is
the Univerfal Vegetation in the Earth, by which
term you are to underſtand fuch natural bodies
as grow and increafe from parts organically.
formed; but that have no fenfation or life.
This effect is not confined alone to plants and
trees, but is extended to fpars, foffils, minerals,
and metals, as Silver difcovers as perfect an ex-
panſion in branches and leaves as Fern; and
Gold grows in grains of different dimenfions:
thus it is demonstrated that metals increaſe in
their proper Earth, or Ores, in a regular pro-
cefs of Vegetation.
Lady
262
On the Terraqueous Globe, &c.
Lady L. I could never have imagined that
Gold was capable of growth, or increaſe of
bulk.
Ment. The laſt branch of theſe wonderful
effects is the Univerfal Plaſtic Power in Na-
ture, by which is meant that Principle which
from the Creation arranged the various forms
of Matter into that beautiful fyftematic order,
which is uniformly manifeft in the general oe-
conomy of the Earth. To this permanent ef-
fect may be ascribed the invariable ſimilarity
and characteriſtic marks that are preferved in
every genus and fpecies of animals, plants, and
the general productions of nature, which never
depart from the leading traits of their genuine
character thus for inftance, Earth, Sand, Gra-
vel, Clay, Loam, &c. are unchangeably of the
fame form or quality. Stones, Flints, Peb-
bles, Slate, Marble, Marcafites, and Metals,
have the ſame ſpecific properties in every region.
Spars, Cryſtals, and precious Stones are al-
ways the fame kind of Body: thus the works of
Nature are uniform in their operations, and
never deviate from the preſcribed line of organic
diftinctions.
Lady M. I fall in future think the Earth
a fubject of importance, and fhall neglect no
oppor-
On the Terraqueous Globe, Sc.
263
Opportunity of obſerving its extraordinary qua-
ities.
Ment. The folid parts of the Earth are
formed of beds or ftrata of different materials,
which lie one upon another in regular order.
The first ftratum conſiſts of Mold, or common
foil, intermixed with a great variety of decayed
vegetable and animal matter blended with fan-
dy and stony particles. In different regions
the other ftrata are found to confift of incon-
gruous materials, variouſly difpofed, ſuch as
Sand, Gravel, Loam, Clays, Argile, Marl,
&c. In fome fituations the ftrata are horizon-
tal, in others they are inclined, and veins or
fiffures of Metals, Coals, and other minerals,
frequently penetrate through the different beds
or ſtrata to a great depth and divide them: every
ftratum, either horizontal or inclined, has an
equal thickneſs throughout its whole extent. In
this maſs of folid matter, the fuperficial, or
that neareſt to the furface of the Earth, is the
leaſt pure in quality; all fubftances derived
from the fea in form of ſediment or fand, and
thoſe compofed of the combinations of the ani-
mal and vegetable productions, and that have
been changed by volcanean fires or fublimed by
the internal heat of the Globe, are transformed
in
264 On the Terraqueous Globe, Sc.
الأمر
in quality, and become vitrifiable, or can be
turned into Glafs, by the fole action of fire, as
all fixed matter, when decompoſed in the great-
eft degree, is reducible ultimately into Glaſs.
You will therefore perceive that the different
firata or beds of which the Earth are compoſed,
confiſt of diſtinct layers of Sand, Stone, Clay,
Shells, Marble, Gravel, Loam, Marl, Chalk,
&c. &c. and thefe beds are invariably parallel
to each other, and of the ſame extent. Chalk
affords a ſtriking inftance, where Nature devi-
ates from the ufual refemblance, between a
production and its parent ftock, as Flint that is
the hardeſt in texture and blacker in hue than
any ftony ſubſtance, is produced from Chalk,
which is of the ſofteſt and whiteft quality it is
not unuſeful here to add the importance of Flint
in ftriking fire with fteel; Chalk alfo is of ex-
tenſive uſe, as it can be converted into Lime,
Whiting, &c. and is the most remarkable ab-
forbent in nature. Chalky hills afford the beſt
Springs 1 foft water, and foften thoſe which
are of a hard quality: and to conclude my eu-
logium on Chalk, I ſhall remark, it is in a va-
riety of caſes efficacious as a medicine, and an
excellent manure for Land: theſe uſeful pro-
perties
On the Terraqueous Globe, &c.
265
perties render it fo valuable, it may be juftly
ranked as a celebrated Foffil.
Lady L. I fear you have. finished the ac-
count of Earth as an element, which I much
regret, as I find it very curious and entertain--
ing.
Ment. There are fome other fpecies of
Earth I will enumerate, as they are of effential
utility to us in the general accommodation of.
life. The first is Fullers Earth, which poffeffes
an extraordinary purifying quality, and is of
great uſe in cleansing cloth from fpots of greafe;
and alfo is of important fervice in manufactur-
ing cloths. The next is the Earth from what
are called the Soapy Rocks in Cornwall, near
the Lizard Point. This fubitance has the ap
pearance of foap, and produces the fame effect
to the eye and touch; but is not poffeffed of
its cleansing quality, yet is of great uſe in ma-
nufactories of China, on account of the white,
fine, and firm grain of its texture,
༣
Lady M. The extraordinary properties of
this Earth, like every other part of the creation,
excite my wonder and admiration.
Ment. I will next endeavour to deſcribe a
remarkable Foffil called Mufcovy Glafs, which
is the most fuperior fpecies of Talk that the
N
Earth
266 On the Terraqueous Globe, &c.
Earth produces. The internal parts conſiſt of
plates or flakes of a thin tranfparent fubftance,
very much reſembling thin fheets of glaſs, and
transparent in proportion to their thickness; and
are often fo thin as to float in the air, and by
reflection, produce the moft brilliant colours in
nature this Foffil is not of a brittle quality,
but pliant, elaſtic, and ſtrong; which render it
of great utility in optics, as it is not eafily af-
fected by fire or flame. Amber is another Fof-
fil, the qualities of which I will briefly ſpecify,
it is ſuppoſed to be of a mineral nature, confift-
ing of a kind of bitumen, that was once in a
fluid ftate, hardened by a mineral acid, which
is evinced, from the number of extraneous
objects obferved in it, fuch as ftraws, ſmall
infects, &c. its native colour is yellow, its fub-
ftance is tranfparent, and of a hard compact
confiftency, admits of a high poliſh, and is of
an inflammable nature. This was the first
ſubſtance obſerved to poffefs an attractive pro-
perty, which I have already mentioned in my
obfervations on electricity. The next ſubſtance
the ancients diſcovered to be of an electric qua-
lity, is now called Tourmalin, and as the Dutch
jewellers found it attracted aſhes, they named
it Aſhes Tracker; as electricity is of two kinds,
amber poffeffes one quality, and glaſs the other,
but
On the Terraqueous Globe, c. 267
but Tourmalin is endued with both, or rather
each fort may be excited in it, the pofitive degree
of electricity being on one fide, and the nega-
tive on the other, which are put in action alone,
by the influence of heat. This Foffil may be
properly faid to be a jewel or gem, endued with
wonderful properties; yet from its ſmall bulk,
is not converted to practical ufes, but is regard-
ed only as a curious object.
Lady L. I never thought Foffils were fo ex-
traordinary in their nature as you defcribe.
Ment. The most renowned and delicate Fof-
fil the Earth affords, is called Ifland Cryſtal,
which is celebrated by naturalifts and philofo-
phers, for its fingular property of a double re-
fraction of light; like other Crystals it is of
a pure pellucid quality, and as clear as water,
and like them grows from the hardeſt rock and
ſtone, in form of hexagonal pyramids, with ve-
ry fharp points. This Crystal is converted to
the form of prifms, and by that means pro-
duces not only a double reflection of one object,
but a multiplicity, which occafion a variety of
prifmatic colours that are of great uſe in the ſci-
ence of optics. As I have already deſcribed
the Magnet or Loadſtone, I will not repeat my
remarks on that ſubject.
N 2
Lady
268
On the Terraqucous Globe, &c.
Lady M. Thefe obfervations on Foffils are
fo new to me, I cannot exprefs the pleaſure
they afford me; but pray my dear Mentoria,
what does the word Foffil imply?
Ment. The term Foffil is derived from the
latin, and means any fubftance which is, or
may be digged out of the Earth; but is more
particularly applied to fome peculiar fpecies,
that are diſcovered in the interior part of its
fubftance. One of the most extraordinary of
this numerous tribe, is the Afbeftos or Amian-
thus, which poffeffes the wonderful quality of
refifting the force of fire. In form and fub-
flance it appears like a common Foffil ſtone
on one fide; but on the other, exactly refem-
bles a piece of fine green filk or fatin; filky fi-
laments run through the whole length, owing
to the firmneſs of its texture, and the natural
polifh of its fibres, which when raifed up with.
the point of a needle, appear of a ſoft filky ſub-
ftance, and as white as cotton. The ancients
poffeffed the art of manufacturing this into fine
webs of filk for garments, and the moderns are
not ignorant of the means, though its rare qua-
lity prevents its common uſe.
Lady M.
muſt have been.
How valuable fuch garments
Ment.
On the Terraqueous Globe, &c.
269
Ment.
This wonderful Foffil is of fo rare a
quality, a fufficiency of the curious fpecimen I
have deſcribed to you cannot be procured; alſo
from its brittle nature it muſt be interwoven with
flax, and when formed into a fine thread, be
put into the fire to deftroy the flax, and by that
means leave a pure Amianthus, Afbeftos, or in-
combustible cloth; this kind of Foffil, which is
found in England, is of an inferior quality and
no great value; as thofe of fuperior excellence,
like every other kind of Foffil, are produced in the
greatest perfection in hot countries.
Lady L. It is wonderful fuch extraordinary
fubtances are found in the Earth.
Ment. The ground on which we tread con-
ceals a fubterraneous mufeum of invaluable
treaſures and curiofit.es; the deeper we penetrate,
the more profound our ideas muſt be of that
Being who created all the fe extraordinary pro-
ductions. The next fpecies of Fofils I thall
deferibe is called Mundic, which is a kind of
Marcafite, efteemed fo.its glowing colours
that are innate and permanent, and when in an
opaque folar microſcope, appear not only great-
ly magnified, but exhibit an inexpreffible de-
gree of refplendent beanty.
N 3
Ment.
170
On the Terraqueous Globe, &c.
Lady M. It would give me great pleaſure
to ſee the objects yon have defcribed, and I hope
my dear Mentoria you will be kind enough to con-
trive fome means of affording me this fatisfaction.
Ment. I will ufe my beft endeavours to that
effect; and ſhall now proceed to give you ſome
idea of that clafs of Foffils which are held in
the higheſt eſtimation, as Jewels, Gems, and
Precious Stones. The Crystal is the most
common kind, it is devoid of colour, tranfpa-
rent, and of a very hard texture, growing
from rocks in a pyramidical form, and
fometines in the fhape of a pebble, as the Bra-
zil kind. Agate is ranked in this clafs, though
very common, it is for the moſt part opaque and
variegated with colours in a beautiful irregular
manner. Jaſper is found in form of a flint or
pebble, and when wrought appears a beautiful
green, fometimes fpotted with white clouds,
and is rarely tranfparent except when it is very
thin. The Emerald is green and in forms of
pebbles and Crystal and when polifhed is of
a beautiful luftre. The Cornelian Sardius or
Sarda, found in pebble form, when poliſhed
is of a whitish flesh colour, or blood-red hue,
and frequently variegated and veined with pale
red and white. Onyx is a precious ftone, femi-
tranfparent, formed in zones about a central
body,
On the Terraqueous Globe, &c.
271
body, which conftitute its beauty.
The Sardo-
-
nyx is nearly of the fame quality, refembling
the Sardius in its flesh colour, and the O-
nyx in its annular marks and tabulated form.
The Topaz is invariably found in an oblong
pebble form; by the ancients it was denomi-
nated Chryfolite from its golden colour, in
which it excels, but varies from a very deep to a
pale tinge. Sapphire is a beautiful gem, dif
tinguiſhed by its azure or ſky coloured blue ap-
pearance. They are fometimes found in colum-
nar cryſtalline forms, and frequently in the
fhape of pebbles, and vary in the tinges of their
colour, from the paleft to the deepest degree.
The Ruby is greatly esteemed for its glowing
red colour and hard texture. The Carbuncle
is only a fpecies of Ruby, but is fo denominated
as when held up to the Sun it reſembles a glow-
ing charcoal, The Beryl is a finer fort of
Crystal, generally of a columnar form, but
alſo found in pebbles, it is of a fine bluish green.
colour, which it never lofes. The Jacinth or
Hyacinth is a Gem of the pellucid fort, of a
red colour with a mixture of yellow; it is of
a columnar form, fometimes found in Pebbles
and is fubject to a great variety of tinges from the
Ruby to Amber. The Amethyst is a ſtone of
a beau.
N 4
272 On the Terraqueous Globe, &c.
a beautiful colour, being a mixture of red and
blue, which produces every degree and gradation
of a purple hue; it is fouud in form of Pebbles.
and Cryſtal. The Garnet is a Gem of a deep
red colour with a caft of blue, variable in its
tinges down to a fleſh colour, it is always found
in the Pebble form, and does not lofe its colour
in fire like other Gems,
Lady M. I fhall view the brilliant Gems.
that you have enumerated with additional plea-
fure ; now you have informed me of their ref-
pective properties.
Ment. There yet remains the moſt reſplen-
dent fpecies of Gem or precious ftone for me
to deſcribe, which is the Adamant or diamond:
this Jewel excels every fubítance in nature by its
peculiar hard quality and the power of refracting
light; it is cut and poliſhed by its own fub-
ſtance reduced to fine powder, and its fuperior
brilliancy is produced by its wonderful refracting
quality, which greatly exceeds that in Cryſtal
or Glaſs. It is found in various forms of
Cryſtal and Cryſtalline pebbles with ſeveral
irregular fides which often have a native poliſh;
its dimenſions are various, the great Mogul has
one, that weighs two ounces and a quarter,
worth feven hundred, feventy nine thouſand,
two
}
On the Terraqueous Globe, &c.
273
two hundred and forty four pounds. The heat
of common fire does not affect this Gem; it is
the produce of the Eaft Indies, and other parts
of the Torrid Zone, where all the fpecies of the
moft valuable precious ftones are alfo found.
Lady L. Diamonds are fo beautiful in their
effect, one cannot fee them without admiration,
accompanied by a wiſh to obtain fuch brilliant
ornaments.
Ment. They may morally be confidered as a
leffon, as well as an external decoration; their
latent brilliancy refembles intrinfic merit and
fuperior abilities, and their refplendent luftre in
a polifhed flate, forcibly inculcates the advan-
tages derived from the joint efforts of ſkill and
judicious refinement.
Lady L. Be affured, my dear Mentoria, I
will be more zealous to refemble the Diamond
in its valuable re plendent qualities, than to pof-
fefs it literally as an exterior diſtinction reſpect-
ing rank or drefs.
Ment, There are fome other Fofils, not
diſtinguiſhed by brilliancy, which are of great
utility in Medicine, Arts, and various occupa-
tions. The Lapis Lazuli, of which the fiueft
blue colour, called Ultramarine, is made. The
Turquoiſe Stone, fometimes reckoned amongst
Geins.
N 5
274
On the Terraquecus Globe, Sc.
1
1
Gems.
Bifmuth and Zink, much uſed in fol-
dering Gold and Silver. Antimony, celebrated
for its medicinal qualities. Native Cinnabar,
which is a kind of Mercurial Ore, from which
Mercury is obtained. Sulphur, the moſt in-
flammable fubftance in nature, and of very
effential ufe in Medicine, and for the common
Bitumen, of a pitchy fulphu-
Afphaltos is alfo of a bitumi-
nous quality. Naptha, a liquid Bitumen, very
inflammable and difficult to extinguish. Petro-
purpoſes of life.
reous, property.
leum, a fulphureous oil diftilling from the clifts
of rocks, and Arfenic, a mineral of a moſt de-
ftructive poiſonous quality.
Lady M. I have heard of fatal accidents,
by perfons taking Arfenic, by accident or de-
fign.
Ment. The mifapplication of a variety of
things proves detrimental, though in many rèſ-
pects they may be uſeful when ſkilfully employ-
ed. As I have finiſhed my account of Mine-
rals, I fhall proceed to inform you the Earth
alfo yields many faline productions, diſtinguiſh-
ed in the following fpecies of Salts, fuch as A-
lum, Sal Ammoniac, Nitre, Borax, Sal Gem,
&c. Vitriols of various kinds, blue, green,
red, white, &c.
Lady
On the Terraqueous Globe,
c.275
Lady L. I have frequently heard theſe things
mentioned, but had not the leaft idea they were
taken out of the Earth..
Ment. The interior part of the Globe is an
inexhaustible magazine of invaluable treaſures:
the fuperficial obſerver, who does not penetrate
beneath its furface, has no knowledge of the
riches unexplored by his narrow conceptions;
whilst the Philofopher and curious Speculator
difcern perfection in every atom of the varied
compound Terreftrial mafs. The Deity may
be traced in the moſt minute object, and his
attributes fhine with equal refplendence in the
common Flint as in the Diamond's blaze! It is
a circumftance which fhould excite our grati-
tude and praiſe, that the feveral varieties of
Stone, Coal, and many other articles which are
of extenfive ufe, are abundantly diffuſed, whilft
Gems and precious Stones are comparatively
rarely found. A diverlity of foil is alſo a re
markable intance of Divine mercy and good-
nefs, as it greatly tends to produce abundance
and diffufiye bleffings. In fome diftricts the
Earth is of a light fandy quality, in others of a
clayey, chalky, ftony, or flinty property, and
in many parts gravelly, or of a mixed ſubſtance,
which conduces to our general accommodation,
N6
f
and
276
On the Terraqueous Globe, &c.
y
and promotes univerfal vegetation. Some re-
gions abound with quarries of Slate, Lime-
ftone, Freeſtone, and Marble, others with mines
or pits of Coal, and a variety of fubterranean
ſubſtances too numerous to be ſpecified, yet too
important to pafs unregarded by the moſt un-
learned of the human race.
DIALOGUE
DIALOGUE XIII.
MONDAY.
On the Terraqueous Globe, Ores,
Metals, Vegetation, and ter-
reſtrial Beings.
A
Mentoria.
SI have no doubt your curioſity is excited
by my account of the various kinds of
Earth and Foffils, I fhall continue our fubter-
ranean reſearch and proceed to inform you of
the nature of Ores and Metals.
Lady L. I have frequently heard of Metals,
nd know in fome degree what they are, but
pray my dear Mentoria what do you mean by
Ores ?
Ment.
278 On the Terraqueous Globe, &.
.
ཧཱ
ccMent. Ore is a hard Mineral Stone, either
Rock or Pebble, which is more or lefs impreg-
nated with particles of Metal, thefe when fepa-
rated from the earthy part, are melted into a
folid mafs or body of pure Metal: I will en-
deavour to give you a conciſe idea of this pro-
cefs. The Miners have ftamping mills, which
by repeatedly breaking the lumps of mineral ore,
at laſt reduce them to a kind of duft or powder,
which is carried by a ſtream of Water from the
mill, over feveral platforms of Wood, lying
one below the other, upon a gradual defcent,
and confequently upon each platform the pow-
dered mineral adheres, in proportion to the fize
and weight of its particles, the loweſt being as
fine as is neceffary. Thus pulverized, it is
conveyed to what is called the Smelting-houſe,
where it is put into a large furnace, with a pro-
per flux to promote its fufion, and there by the
influence of the Fire it is melted, and finks to
the bottom in a fluid ftate, and the Earthy part
all rifes to the top by being of a lighter quality.
The melted metal is drained off into fuitable
veſſels, where it gradually confolidates by cold
into mally fubftances of metal, fuch as Blocks,
Ingots, &c. &c. I have previouſly obſerved
+
the various effects of vegetation in ſilver ore,
which
On the Terraqueous Globe, &c. 279
which appears like branches and leaves in a
multiplicity of beautiful forms. Copper Ore
is alſo remarkable for the variety of brilliant
tints it exhibits, and it is generally fuppofed,
produces the different hues in the feveral ſpecies
of Marcafites or Mundics, Cryſtals, Precious
Stones, &c.
>
Lady L. Theſe circumftances appear very
extraordinary, I cannot forbear expreffing my
admiration of their beneficial effects; how ma-
ny kind of Metals are there?
Ment. From thoſe properly called Metallic
Ores, only ſeven, Gold, Silver, Copper, Iron,
Tin, Lead, and Mercury, which all agreè in
the common character or nature of Metal, viz.
a hard fhining mineral body, fufible by various
degrees of heat, principally Fire, ſubject to its
particles being concreted by cold, malleable or
ductile under the hammer, or any other weight,
and ſpecifically the heaviest of all Bodies.
Lady L. Is not Gold the moſt valuable Me-
tal ?
Ment. It is not only the moſt valuable, but
the purest of all compound bodies; it is proved
to be the heaviest by being 19 and a half times
more weighty than water; and is more ductile
or malleable than any other metal. It is fufible
(that
280 On the Terraqueous Globe, &c.
(that is, can be melted in the Fire), but is more
fixed, and lofes lefs in the Fire than any other
metallic ſubſtance. It is of a yellow colour by
reflected Light, and of an azure colour by re-
fracted Light, through the thin leaves thereof ;
has an obtufe found, and is only diffolvable in
Aqua Regia and Mercury. Gold is fometimes
though but rarely found in Ore, often in its na-
tive ftate, but most commonly in fmall Grains
or Dult in the fand of many Rivers on the Gold
Coaſt of Guinea, and 'many other places.
Lady L. Which is the next Metal that
are to deſcribe, my dear Mentoria ?
you
Ment. Next to Gold, Silver is the moſt
pure, fixed, and ductile Metal. It is of a per-
fect white colour, and reſpecting its growth and
form, bears a greater degree of fimilitude to ve-
getable ſubſtances than any other metallic body:
it can be diffolved into a pellucid fluid, by Aqua
Fortis, and poffeffes no colour. The next
Metal in regular order is Copper, which is pe-
culiarly diſtinguiſhed by its found, or ſonorous
quality. It is of a red, or deep purple colour,
but gives a fine blue to a folution of it. It is
chiefly found in a very hard ftone of a dark co-
lour, running in veins between beds or layers
of rocky Earth or Stone; and fometimes in its
pure
On the Terraqueous Globe, &c. 281
pure native form of a perfect malleable quality.
It appears to have a vegetative power of ſhoot-
ing into twigs and branches, and very frequent-
ly exudes in the mine, in form of blue pointed
fhining Cryſtals, in large heads of. fix or eight
inches wide, which have a beautiful appear-
ance.
Pray, Mentoria, what are the
Lady M.
qualities of Iron ?
Ment. Iron is the hardeſt of all metals, it
is fufible by only the greatest degree of heat, but
malleable and ductile with a common red hot
heat, and may be hammered till it becomes red
hot, and is the only body in Nature fufceptible
of the Magnetic power. It diffolves in Aqua
Fortis very eaſily, and more rapidly than any
other metal, but is corroded, by the acid in the
air, and becomes rufty. When red hot under
the hammer, it emits fcales or flakes of calcined
iron, highly magnetical. Iron is never found
pure, but always in Ore, either Pebble or a
hard Stone, it may be extracted by the Load-
ftone from the Ashes of Plants, and in Cryſ-
talizing, diſcovers lefs of a vegetable form than
any other Metal; it is of a whitifh glittering
colour when broken.
Lady
-282 On the Terraqueous Globe, &c.
ए
Lady L. I recollect Tin is the next Metal,
according to the rank or order you mentioned.
them in.
Ment. Tin is the lightest of all Metals, in co-
lour it is as white as Silver, but fofter than any
other Metal except Lead. It melts with a ſmall
- degree of heat, is malleable, not very ſubject to
ruft, and poffeffes no fonorous quality. It has
the leaft fixity in fire of any Metal, eafily blends
with other kinds, all of which it renders brittle.
except Iron. It is found in Ore of hard ſtone,
and alfo in opaque Pebbles.
Lady L. I am greatly indebted to you for
informing me of the properties of fuch uſeful
and valuable productions of Nature by which I
benefited, but was not fenfible of their extra-
ordinary qualities.
}
Ment. Lead is the next metal I am, to def-
cribe; it is the heaviest of all metallic fub-
ftances, except Gold and Mercury. It is the
fofteſt of all Metals, confequently melts the
fooneft, and is very ductile and flexible, and
leſs ſonorous than any other kind, and the leaſt
fixed by Fire. It is feldom found pure, but in
an Ore of a gloffy black hue.
Lady
L
On the Terraqueous Globe, &c.
283
Lady L. I fear you are now come to the
laft branch of the Metallic Ores, which is Mer-
cury.
Ment, The properties of Mercury, or
Quick-filver, will require particular explana-
tion; though a Metal, it is a Fluid Body, there-
fore you muſt underſtand that Fluidity is one
ftate of Metal produced by a certain degree of
heat, and fixity or folidity is another, by a de-
gree of cold that our air invariably affords, which
is found infufficient to fix Mercury, or convert
it into a folid body, even in the frigid regions
at the Arctic circle; though at Peterſburg an
artificial degree of cold has been made to fix it
into a body as hard as Lead, and whiter than
Tin when cut, and to render it ductile and
malleable, by which is meant a ſtate capable of
being beat by a hammer.
}
Lady M. In your defcription of Metals I
am ſurpriſed that you have made no mention of
Brafs, Steel, or Pewter.
Ment. They are not natural, but factitious.
metals that are made by art.
Brafs is a com-
pound produced by mixing pulverized Cala-
mine ſtone with Copper, which by letting it
ſtand a proper time in a wind furnace, is con-
verted into Brafs. Steel is not a diftin&t Metal
from
284 On the Terraqueous Globe, &c.
}
from Iron, but only fo purited and altered by
art, as to be of a finer grain and of a harder
quality, confequently better fuited for making
fharp inftruments and implements to cut with.
Pewter is a compound of feveral metals and mi-
nerals fo compounded, as Tin mixed with Lead
and Brafs, Bifmüth, &c. Tin Plates are in
reality Iron plates covered, with Tin on both
fides, and are penetrated fo flrongly by the Tin,
they appear to be fuch by the whitenefs when
cut; but ftill the Iron retains its magnetic qua-
lity. There is alfo a new mineial, called Pla-
tina, which is even heavier than Gold, and in
colour reſembles that Metal, but is very hard
and brittle; when blended with Gold or Silver
it produces a rich compound, fuperior in quality
to Bell Metal, Pinchbeck, or Princes Metal,
of which a variety of articles are made. I have
been very explicit and diffufe in my remarks
on metallic ſubſtances, as inoft fpecies of metals
are of effential utility. In the first inftance,
Gold and Silver, by being converted into cur-
rent coin, produce the various accommodations
of life; and from the value, by the general con-
fent of all civilized nations intrinfically allowed
to them, in a great degree conftitute wealth.
It is fcarcely poffible to enumerate the advan-
tages
On the Terraqueous Globe, &c. 285
tages we derive from Copper, Iron, Tin, and
Lead, if it were not for the ſeveral properties of
thofe metals, we could have no buildings or hips
conftructed, no ufeful implements or utentils
made for agriculture or domeftic purpoſes, and,
in fine, our fituation must be reduced to nearly
a favage ftate, refpecting the varied comforts
and conveniences of ſocial intercourfe. From
Mercury we receive many benefits we are not
in every inſtance able to trace, as it is uſed in a
variety of means, and produces many good ef-
fects philofophically and medicinally, which
would be beyond your comprehenfion and my
prefent purpoſe to explain. I have dwelt more
on theſe ſubterranean treaſures, as I am con-
vinced very few comparatively have a clear no-
tion of their importance and wonderful quali-
ties, though in other refpects what are ufually.
termed well-informed and cultivated by a liberal
education; thus many who are deeply fkilled in
fcientific learning are totally ignorant of the pro-
ductions of Nature, and the general fyftem of
the Univerſe.
Lady L. I am furprized that the generality
of perfons fhould be fo inattentive to ſubjects of
fuch importance.
Ment.
286. On the Terraqueous Globe, &c.
Ment. This almoſt univerſal confequence
arifes from the prevailing erroneous habit of
confining inſtruction. to particular branches of
knowledge, ufually called fcholaftic or claffical,
which render perfons learned refpecting words,
and ignorant concerning the general structure.
and properties of things. As I have endea-
voured to explain the interior productions of the
Earth, I fhall now proceed to confider thoſe
inftances of Divine power exemplified in the
varied vegetable ſubſtances that grow on its fur-
face. Vegetative Nature differs very eſſentially
from animal exiftence, as it confifts alone in
growth, which is commonly called its life. E-
very Plant properly defined confifts of various
determinate parts, which have this vegetative
power by Nature, of unfolding themſelves from
a certain fixed point or bafis downward into the
Earth, and upward into the Air: the defcend-
ing part is gradually unravelled, protruded, ex-
tended, and carried forwards in numberless
branches and ramifications through the circum-
jacent parts of the refifting Earth, Stones,
Rocks, &c. to the moft filamentary ftate; and
this affemblage of parts is called the Root. The
afcending part confifts of much greater variety,
and in fact conftitutes the whole fubftance of the
Plant
On the Terraqueous Globe, &c.
287
Plant in miniature. The vegetative power in
the Earth cauſes the feveral parts in the Plantula
(or embryo of the plant contained in the feed) to
evolve and unfold themſelves by imperceptible
degrees, til at length they are ſeparated one
from the other, and appear above ground in the
proper and ſpecific forms in what are called
Leaves, Blades, Stalks, Stems, Branches, Flow-
ers, Seeds, &c. which compofe the adult, com-
plete Plant.
Lady M. I have frequently fown feeds in
the garden, and obferved with much pleaſure
their gradual proceſs of growth.
Ment. Every Seed contains in itſelf the
whole Plant's fimilitude on a ſmall ſcale which
produced it: this Plantule, or Plantula, is
placed in the fide of each Seed, confifting of two
parts called Lobes; it is included between and
connected with both on the fide where they
join. The economy of the circulation of flu-
ids through the body of the Plant, is as incom-
prehenfible as that in the body of animals in ge-
neral, though its obvious mechanical principle
is produced by the natural power of attraction
between the particles of matter in bodies. If
we attentively examine each particular part of a
Plant, they appear to be created for fome im-
portant
288
On the Terraqueous Globe, c.
portant purpoſe or ufe, the Root for its flability`
and nourishment from the Earth, the Fibres to
contain and convey the Sap,
are a large fort of veffels to
and ſpecific juice of the
befides which there
contain the proper
Plant, and others to
carry air for the degree of refpiration neceſſary
to its existence. The outer and inner Bark of
Trees ferve to defend the Trunk and Boughs
from the exceffes of heat, cold, and drought,
and to convey the Sap or vegetative nourishment
for the annual augmentation of the Tree, every
fpecies of which may in fome degree be faid
to be an annual Plant, as the Leaf, Flower
and Fruit proceeding from the coat that was
fuperinduced over the wood the laft year, which-
never bears any more, but with the old wood
ferves as a block to fulain the fucceeding annu-
al coat or covering. The Leaves ferve before
the Gemma or Bud is explicated, to defend the
Flower and Fruit, which are even then perfectly
formed, and afterward to preferve the Branches,
Flowers, and Fruit from the intenfe effects of
the Solar heat, and alſo to prevent the too rapid
evaporation of the moiſture about the Root.
is worthy of obfervation, that notwithstanding
Plants by culture and manure may be highly
improved in quality and dimenfions, yet the
It
fame
On the Terraqueous Globe, Sc. 289
fame Plaſtic Power which operates in every o-
ther part of the Creation prevents their exceed-
ing in growth beyond the limits of their original
Specific form.
Lady L. A Garden affords fuch a variety
of pleaſures, it is fcarcely poffible to ſuppoſe
any perfon wholly infenfible to their impreffive
effects.
Ment. Horticulture, or that kind of ſtudy
which is confined to the cultivation of Gardens,
is a purſuit fraught with innumerable ſources of
delight and improvement; yet Vegetation is fo
diffuſive in its extent, and in every branch even
in its wildeſt ſtate abounds with ſpecimens to
excite our wonder and admiration: I fhall there-
fore briefly confider its general effects. In the
first instance, the greateſt part of the dry land is
covered with a kind of carpet of green grafs and
other herbs, not only moſt pleaſing, but the
moſt falutary to the viſual organs, and this is
alfo decked with great variety of Flowers of
beautiful colours and forms, poffeffed of fara.
tive and fragrant odours, conducive to our gra-
tification, and the refreshment of our animal
fpirits. The Earth is likewife furniſhed with
beautiful Shrubs and ſtately Trecs, affording us
not only pleaſant and nouriſhing Fruits, many
O
Gums,
290 On the Terraqueous Globe, F.
Gums, Liquors, as Turpentine, Tar, &c. Drugs,
and valuable Medicines; but alfo Timber and
utenfils for all kinds of trade and varied occu-
pations conducive to the general convenience of
the human race, and the fupport of fubordinate.
animals. It is graciouſly ordained by Provi-
dence, that vegetables which are defigned for
animal fuftenance are abundantly produced and
increaſed, and many propagated not only by the
Seed, but alſo by the Root producing off-ſets,
fome by creeping under ground, and others a-
bove the furface of the Earth. It is a ftriking
proof of Divine mercy, that thofe kinds of grain
which are defined under the general term of
Corn, (by which you are to comprehend all
that are of a quality to make Bread) fuch as
Wheat, Rye, Barley, and Oats, are very gene-
rally diffufed; and that Wheat, which is the
pureſt and moſt falutary kind, flouriſhes not
only in temperate, but in regions of an extreme
hot and cold climate, and is alfo of a remarka-
ble fruitful nature; which even Pliny, who was
a Heathen, produced as an argument in favour
of the bounty of God difpenfed to Man. When
we reflect what myriads of beings are fupported
by herbs, grain, and general vegetation, we are
naturally led to acknowledge the wonderful
pro-
vifion
On the Terraqueous Globe, c.
291
vifion that is made for every fpecies and grada-
tion of animal life. The Earth yields an am
ple ſtore of every requifite to fuftain the general
œconomy of the Mundane fyftem, every parti-
cle of which is fubject to the fame general laws
and properties, as thofe clearly defined and ſpe-
cified in the regular order of the Univerſe, Ter-
reſtrial as well as Celeſtial. On a general fur-
vey of theſe bleffings, it would be a heinous fpe-
cies of neglect to withhold that tribute of grate-
ful acknowledgment for the benefits which, as
inhabitants of the Terraqueous Globe, we en-
joy from the combined effects of the varied per-
fections I have fo imperfectly delineated. The
Earth is the baſis and fupport of all animals
and Plants, and affords them the hard and folid
parts of their bodies, yielding us not only food
and fuftenance, but alfo raiment. The beings
uſually called Terreſtrial animals, from being
inhabitants of the Earth as their congenial Ele-
ment, are Man, Quadrupeds, Infects, and
Reptiles; theſe are all refpectively fo judici-
oufly arranged, that the moſt perfect harmony
fubfifts. Beafts of Prey are confined to deferts
and their native dens, by the reftraining hand of
Providence; whilſt thoſe which are docile and
domeſtic, are more generally diffuſed, and by
O 2
their
292 On the Terraqueous Glabe, &c.
their varied properties conduce either to our
fuftenance or convenience, fome being fit for
food, others for the fupport of burthens and la-
borious purpoſes, and many for our effential
benefit or amuſement. The noble qualities of
the Horſe, the fidelity of the Dog, the utility
of Oxen, Cows, and Sheep, are fubjects which
muft afford rational grounds for admiration.
The degree of instinct approaching to rationa-
lity, exemplified in the Elephant and Beaver,
and the eminent portion of fagacity found in a
great variety of other animals, cannot fail to
mpreis a contemplative mind with a juſt ſenſe
of Dine Wiſdom, more eſpecially when we
reflect that thefe beings, though fuperior in
ſtrength, are fubordinate to the human race, to
whom they are under fubjection by the decrees
of all gracious Providence. I will next confi
der the nature of Infects, which are fo called,
as their bodies appear as it were infected or di-
vided into different parts, their eyes are all fixed
in their heads, and not moveable as in other
animals; every fpecies of winged Infects have
but two eyes, but all the different kinds of ſpi-
ders have ſome four, many fix, and others eight.
The Infect Tribe is fo numerous, I fhall not
attempt to enumerate them, but ſhall only re-
mark
On the Terraqueous Globe, &c.
293
mark they vary very effentially, the fame ani-
mal being at one time an Infect, the next a
mere Reptile, and afterwards neither Infe&t nor
Reptile, and are alfo Aquatic as well as Terref
trial. The various changes of the Butterfly
and Silk-worm are well known; and many
remarkable inſtances might be produced of ſe-
veral tranfmutations in form and quality, that
would be beyond my prefent purpoſe to def-
cribe. The mechaniſm of the ſmallest Infec
is a ſubject of moft exquifite fymmetry, and
frequently of refplendent beauty; and their o-
perations, in their feveral allotments and ſtations,
extremely curious. The Spider, the Bee, the
Silk-worn, and the Ant, afford leffons of in-
genuity, induſtry, and prudent oeconomy, wor-
thy of praife, and in many refpects of imita-
tion. Spiders are not in reality proper Infects,
as they have no feelers, no wings, more eyes,
and more legs, and their heads are joined to
their bodies; fome Infects have two tranfpa-
rent membraneous Wings, with ſmall hairs or
briftles on the furface, and others have four
wings, two large and two finall.
Lady M. Pray my dear Mentoria, what is
a Reptile?
0 3
Ment.
R
204
On the Terraqueous Globe, Ut.
Ment. Any thing that creeps or crawls along
with many fmall feet, which caufes them gene-
rally to be called Multipedes, many of this
tribe have been denominated Centipedes, as if
they had a hundred feet, and many Milepedés,
as if they had a thoufand; which is not to be
underfood literally, but as implying, that the
animal has a great number of feet; ſuch as
Wood-Lice, Caterpillars, moft Worms, and
all the Lizard kind; for notwithstanding they
have but four feet, they move by creepting and
crawling along. Snails alfo have no diftinct
legs, yet belong to the Reptile claſs, as their
motions confiſt in gliding on the ſurface of any
fubftance.
Lady L. Are not Reptiles ufually confidered
as an inferior order of beings?
Ment. They poffefs many extraordinary
qualities, though perhaps not fuch diffinguiſhing
marks of excellence as many other parts of the
creation. I will next engage your attention on
the Feathered Race, which are the moſt gay,
melodious, and elegant fpecies of animals that
exit. If we confider the beauty of their plu-
mage, the exquifite harmony of fome of their
notes, the wonderful inftinct they difplay in
*forming their nefts, and rearing their young;
WG
On the Terraqueous Globe &c.
295
$
we muſt allow they are poffeffed of many emi-
nent qualities, as they delight the eye by their
exterior perfections, charm the ear by the moſt
perfect melody, and regale the appetite, by the
delicious quality of the fleth in many fpecies;
and by their great variety, and brilliant colours,
enliven the general appearance of nature. Birds.
that have a carnivorous appetite, are called
Birds of Prey, fuch as the Eagle, Vulture, Kite,
Hawk, &c. The feathered tribe are alfo di-
vided into two kinds, Land and Water Fowl,
which clearly diftinguithes their proper element.
When the formation and plumage of Birds are
attentively confidered, they appear to be poffeff-
ed of extraordinary beauty and agility; it is alfo
remarkable, that fome can fwim, whilft thofe
of lighter bodies, fly to great heights, and many
migrate at ftated feafons, and return in regular
order to their native regions. In theſe annual
excurfive flights, thefe delicate beings must be
ſubject to great exertions and difficulties, and
proceed with a degree of regularity which would
not diſgrace an army of veteran troops.
Lady M. I admire Birds, and take great
pleaſure in keeping and feeding them.
Ment. Every purſuit that tends to increaſe
your reverence for the Author of Nature, is
O 4
laudable
296 On the Terraqueous Globe, e.
faudable, and to a mind unperverted from a just
fenfe of the Divine attributes, every, the moit
minute object excites grateful fenfations. On
a moral retroſpect of the Terraqueous Globe,
we fhall find it abounds with varied fubflantial
provifion for its numerous inhabitants. The
beafts of the field are furnished with pafturage,
herbaceous, and farinacious food, Infects and
Reptiles are amply fupplied with fuftenance by
the various productions of vegetation. Birds
are fupported by feeds, fruits, and an infinitude
of refources the fields and gardens afford; and
as it is the property of moft animals to prey on
thofe of an inferior quality, they eat infects and
reptiles, whilft many animals of fuperior
ftrength and magnitude prey on them; this uni-
verfal property produces a general kind of car-
nage, as the human race are nouriſhed and fup-
ported by the inferior beings, which by the ex-
prefs appointment of their Maker, are created
for their ufe, and fubmitted to their care and
protection.
P
DIALOGUE
+
t
DIALOGUE XIV.
TUESD Á Y.
On Mountains, Rivers, the Sea,
Submarine Productions, Fiſhes,
Amphibious Animals, and Zoo-
phytes.
}
Mentoria.
IN
N´our progreſſive inveſtigation of the won-
derful qualities of the component parts of
the Terraqueous Globe, the next that demands
our attention is Mountains.
Lady Louifa. I know that Rocks and Moun-
tains are of a great fize and ftupendous height;
but pray Mentoria be very explicit refpecting
their feveral ufes and conftruction.
O 5
Ment's
298
On Mountains, &c.
}
Ment. A Mountain, or high hill is a part
of the Earth rifing to a confiderable height above
the level of its furface; and a rock is a large
mafs of ftone, rooted in the ground. The ori-
gin of Mountains, many fuppofe, was the na-
tural effect of the Deluge, whilft others main-
tain they have been produced by exploſions, by
the means of fubterranean fires, and that they
have probably great concavities beneath them;
fince it has been proved that fubterranean fires.
have raged in caverns under the fea. By ma-
ny, Mountains are rafhly confidered as excref
cences or imperfections, yet in reality they are
productive of great benefit to the human race,
and many ſpecies of animals, by affording fhel-
ter from the intenfe cold of the Northern and
Eaftern winds, and ferve alfo for the production
of a variety of vegetables and minerals, to which
no other foil is congenial. Thefe terreftrial
protuberances greatly add to the beauty of the
fcene, by the contrafted variety they produce of
hills and vallies; as it is certain if the Earth
were an even flat furface, the fea would cover
the whole Globe, and hence become only the
habitation of fishes and aquatic animals.
Lady Mary. That would be a dreadful fitua
tion, I will never in future preſume to wifh
any
On Mountains, Sc.
299
any part of the univerſe different from what is
produced by the unerring effects of Divine wif-
dom.
4
Ment. This determination will prove an ef-
feaual barrier against hafty conjectures, and
confequent erroneous opinions; as we may de-
pend that there is not an atom in the whole Vu-
lume of Nature, incongruous to the organic
conſtruction of the complete fyftem. In proof
of this affertion, it is evident the continuity of
ridges and chains of lofty mountains, generally
being found to run from Eaft to Weft, confe-.
quently prevent the progreſs of the vapours to-
wards the Poles, without which they would all-
run from hot countries and leave them deftitute
of Rain. Mr. Ray remarks, as an argument
of the importance of Mountains, that they con-
denſe theſe vapours like Alembic heads (by
which you are to underſtand a veffel uſed for the
purpoſe of diftilling liquids) and ſo by a kind of
external diftillation, give origin to Springs and
Rivers, and by that means, and by amathing,
cooling, and compacting them into Rain, ren-
der the torrid regions habitable. Mountainous
fituations are alfo the only temperature in which
animals of feveral defcriptions can exift.
0.6
>
Lady
300
On Mountains, Sc.
!
Lady L. I am now fully convinced of the
advantages derived from Mountains, and will
never be weak enough to with the Earth were a
perfect level furface.
!
Ment. To the benefits I have already fpeci.
fied, I must add their importance by the produc-
tion of Metals and Minerals; as the mountain-
ous parts of the Earth, though apparently only
very large and high Rocks, frequently covered
on the outfide with verdure and herbage, are
interiorly compofed of Mines which contain all
thofe productions, to which we annex the idea
of intrinfic values Mountains, by the diverſity
of the foil, are remarkable for producing the
greateſt variety of vegetables, and peculiarly
thoſe appropriated to medicinal purpoſes; they
alfo prove in fome degree boundaries and de-
fences to the territories and kingdoms in conti-
nental countries.
Lady M. When you are defcribing Moun-
tains, you fometimes mention Rocks; in what
degree, my dear Mentoria, are they counected?
Ment. All the Earthy fubftances of which
fome Mountains are compofed, and with which
they might once have been covered, have for
ages been waſhed away from their fummit, and
nothing is left remaining but immenfe Rocks,
that
X
On Mountains, &c.
130
that no tempeſt has been able to deſtroy, which
cauſe the tops of Mountains to be bare and
pointed, and occafion thofe maffes of Rocky
fubftances that frequently fall from tremendous
precipices. When Hills and Rocks are found
formed of a heterogeneous mafs of Marine pro-
ductions in inland fituations, fuch as thells and
ftalks of Sca-weed, and in other refpects of a
fimilar quality with thofe which ſtand within.
low water mark, it is reafonable to fuppofe they
are fo many wrecks and monuments of the ge-
neral devaſtation the Deluge produced; as a maſs
incorporated with petrified Sea bodies cannot
otherwiſe be probably accounted for at fo re-
mote a diſtance from their genuine native fource.
Lady L. Are there not a great number of
Rocks in and near the Sea ?
Ment. Undoubtedly, and which frequently
produce the moſt fatal effects to mariners by the
calamity ufually called fhipwreck, occafioned
by the veffels dafſhing againſt the Rocks. Thefe
fubſtances are formed of the common fediment
of the Sea, as fand, bones of Fifhes, ftalks of
Sea Weed, empty Shells, and a variety of ex-
traneous marine productions, that are rolled in-
to beds by the conftant agitation of the Waters,
and thus being blended together, by the violence
of
302
On Mountains, c.
of the flux and reflux of the Sea, are banked up
towards the fhore, which is the caufe of the in-
clination or dipping of Rocks. No fooner is
this ftratum laid, than there is a continual ac-
ceffion of the fame matter, till the maſs has
reached a certain height in Water. Theſe loofe
materials, as foon as vegetation commences, are
adhered by a ſtrong cement, and affume the con-
fiftency of Stone, and frequently appear like
white Marble, capable of a high polish: this
definition I hope will give you a clear idea of
Rocky fubftances.
Lady M. I now have a clear notion of
Rocks and Mountains, but pray Mentoria def-
cribe what Volcanoes are, and by what means
produced?
Ment, Burning Mountains, ufually called
Volcanoes, contain in their interior parts ful-
phur and bitumen, with other combuſtible mat,
ter, which ferve as food to a fubterranean fire.
The orifice from which the eruptions proceed,
are often of great extent, from whence iffue
flame, streams, or rivers of bitumen, fulphur,
melted metal, and clouds of calcined ſtones,
cinders, and enormous maſſes of Rocks, which
are tremendous in their operations, cauſe Earth-
quakes, deftroy cities, overthrow, Mountains,
and
On Mountains, Sc.
303
and agitate the Sea. In Europe there are three
remarkable Volcanoes, Mount Etna, Mount
Vefuvius, and Mount Hecla. In Afia and A-
merica there are a great number of burning
Mountains that fometimes emit fire and fmoke,
and alſo in Africa there are feveral phænomena
of this kind: In continental countries, the
Mountains uſually form chains, and in Iſlands
are generally more diſtinct and raiſed above the
Sea in pyramidical or conical forms, and are
denominated Peaks; all theſe prominences are
maffes of Rocks heaped one upon the other,
from fome of their fummits occationally emit-
ting burning matter fimilar to Volcanoes. Pre-
cipices that are between Rocks, are cauſed by
the finking of Rocks, from the effect of air and
froft which ſeparates them, and by the joint ef-
fort of torrents, they are divided into a variety
of cleft forms.
ร
Lady L. I believe the next fubject you are
to illuſtrate will be Rivers; I expect they will
prove a pleafing contrast to the burning Moun-
tains.
Ment. In defining the properties of Rivers,
we fhall find they are only Waters defcending
by their gravity to lover parts of the furface of
the Earth, in proper channels, and are entirely
occa-
304
On Mountains, Fc.
葛
​occafioned by great quantities of Water col-
lected on the tops, and fides of Mountains and
high lands, from the accumulated vapours of
Rain, Snow, Fogs, Dews, and alfo Clouds,
which run through various chinks and apertures
into their internal cavities and refervoirs, ti b
they are completely filled. The fuperfluous
Water afterward flows through various channels
and receffes to the fides of Mountains, where
they form in concavities Pools, Ponds, or Lakes,
and alſo operate as bubbling Springs, many of
which are of a perennial, others of an intermit-
ting, and fome of a reciprocating quality.
Lady M. I have heard you frequently men-
tion the Head and Mouth of Rivers, what do
thefe terms fignify?
Ment. The Head of the River is the fource.
from which it firft fprings, and the Mouth im-
plies where it empties or difcharges itſelf into
fome Sea: thus the Nile rifes in the Abyffinian
Mountains and falls into the Egyptian Sea, a
fituation immortalized-in Fame, by Lord Nel-
fon's brilliant victory.
of your
Lady L. I recollect your fhewing me the
feven Mouths of the Nile, in the maps
facred hiſtory. Pray, Mentoria, what are the
principal benefits that we derive from Rivers ?
Ment.
On Mountains, &c.
305
Ment. They are fo diffufive, I cannot pof-
fibly reduce them to any ſpecific form or num-
ber. In the first instance, their flux and reflux
occafioned by the influence of Tides, which I
have already explained, are produced by the at-
tractive powers of the Sun and Moon on the
Ocean, and prevent that ftagnation which would
inevitably render the water of a putrid quality,
confequently of a deftructive tendency. In the
next place, Rivers fupply water for the general
accommodation of life, are indifpenfibly necef-
fary for Navigation, driving of Mills, working
of Engines, and a variety of other important
purpoſes, beyond my ability to ſpecify. Rivers
poffefs many extraordinary qualities; the prin-
cipal Rivers fall into the Sea; but there are
fome that loſe themſelves in the fand, and others
that appear to penetrate into the Earth; it is
alfo obfervable, that in inland fituations at a dif
tance from the Sea, they flow in a direct line,
but as they are near their Mouths they acquire
more of a winding or ferpentine courfe in their
progreffion.
Lady L. Pray, Mentoria, what are Lakes?
Mint. A Lake is a ſtanding pool, or great
collection of waters, which differ in quality;
fome have no connection with any River, and
from
306
On Mountains, Sc.
from which no water goes out; others do re-
ceive Rivers, and from which alfo others run;
and there are fome which only receive Rivers.
{
I fhall not ſpecify the different Lakes, as I fully
explained that branch in my Lecture on Geo-
graphy. :
Lady M.
As you have finished your ac-
count of Rivers, I fuppofe the next fubject of
your instructions will be the Sea.
Ment. Sea is a general term adopted to ex-
prefs the immenfe body of falt water oppoſed to
that of Rivers, which is of a different quality;
though thoſe vaft briny expanfes that encom-
paſs the Globe, with stricter propriety are de-
nominated the Ocean, the word Sea being with
more juftice applied to denote a particular part
or divifion of the general mafs, often fo called
from the countries it waſhes, or from other
circumſtances, as the Irifh Sea, Mediterranean
Sea, &c. &c.
Lady L. The Sea is an object that I con-
template with great delight; therefore I wish
to be informed of its dimenfions, and moft im-
portant uſes.
Ment. The extent of the fuperficies of the
Sea, compared to that of the Land, is not pre-
ciſely aſcertained, though it is generally fup-
pofed
On Mountains, c.
307
pofed to exceed two thirds. As the Waters of
the Earth must neceffarily rife to the ſurface
thereof, as being fpecifically of a lighter quali-
ty; it was expedient there fhould be large ca-
vities, as receptacles to contain théin, or they
would have overfpread the fuperficies of the
Globe, and rendered it uninhabitable for ter-
reſtrial animals.
Lady M. What would have been the im-
mediate caufe of that dreadful effect?
Ment. The centre of the Earth is fuppofed
to be of a magnetic quality, by being the com-
mon centre of Gravity, to which all objects on
the Terraqueous Globe invariably are attract-
ed; and as it is the nature of Fluids, that they
equally yield to equal powers, and the power of
attraction being every where equal, at equal dif
tances from the centre, it follows as a natural
confequence that the fuperficial parts of the Wa-
ter will every where conform themſelves to an
equi-diftant fituation from the centre, and by
that means conftitute the furface of a fphere, as
far as they extend.
Lady M. This rationally accounts for what
before appeared to me inexplicable; but pray,
my dear Mentoria, what is the depth of the
Sea?
Ment.
308
}
On Mountains, Sc.
Ment. The depth or profundity of the
巍
​cean in fome places is afferted to be unfathom-
able, and in others variable, fome few parts are
above a mile deep, but the most common
depths are from 60 to 150 fathom ; and the
profundities are much lefs in Gulphs and Bays
than in Oceans; and in general the depth of the
Sea bears a great analogy to the height of moun-
tains on land.
Lady L. I am furprized fo many Rivers
falling into the Sea, do not cauſe it to over-
flow.
7
Ment. The chief caufe why the Sea does.
not encreaſe by the means of a vaſt acceffion
of waters from Rivers, is principally occafioned
by the Waters returning from the Sea by fubter-
ranean cavities, and aqueducts, through vari-
ous parts of the Earth; and alfo from the quan-
tity of vapours raifed from the Sea and falling
on the land which by that means cauſe only a
circulation, but no increaſe of Water.
Lady L. It is furprifing that the Sea, which
frequently appears fo tempeftuous, does not at
thofe periods inundate the land.
Ment. It can only be ascribed to the om-
nifcient decrees of an over- ruling Providence;
that the Sea fhould compofe itſelf to a level, or
equal
On Mountains, Sc.
309
equal fuperficies, and with the Earth be com-
priſed into a ſpherical form, and that it ſhould
alfo be defined by ftrands, fhores, and certain
limits: as however the Sea, may appear to rage,
its Divine Creator thus proclaims, ** thus far
fhalt thou go, but no further! Notwithstand-
ing the Sea does not exceed its bounds in a de-
gree to prove deftructive, in fome inftances fe-
veral encroachments have been made, of no im-
portance when confidered as relatively connected
with the general ceconomy of the univerfe. It
is a matter of difpute whether thoſe encroach-
ments made by the Sea on the land, or whether
the Land or the Water are gaining on each´o-
ther, in this terraqueous Globe. In Great Bri-
tain feveral encroachments have been remarked;
in the time of Auguftus, the Ille of Wight was
a part of the Iſland of Britain, fo that at that
period the Britons croffed over towards it with
carts loaded with Tin. In general on the Eaſt-
ern fide, the Sea has gained ground, whilft on
the Southern and Weſtern it has increaſed in
fame places, and loſt in others.
Lady L. What produces the beautiful Waves
and different appearances of the Sea?
Ment.
The natural effects of the Flux and
Reflux of the Sea, by the mutual attraction of
the
310
On Mountains, Ec.
the Sun and Moon, but principally of the latter,
which I have fully defcribed in my explana-
tion of the doctrine of Tides, as produced by
the univerfal power of the Laws of Gravity
and Attraction. The Waves, Billows, and
Surges which caufe fuch a varied fublime effect,
are occafioned by the agitation of fo vaft a body
of Water, by the efforts of the Winds and the
joint influence of the Tides: and their diverſity
of tints and hues is derived from the Solar rays
emitting light in peculiar directions. The falt-
nefs of Sea Water is on very rational grounds
afcribed to Mines and Mountains of Salt dif
perſed in the depths of the Sea; this faline pro-
perty is of diffufive utility, as it preſerves the
great expanſe of Water from the effects of pu-
trefaction, by keeping it pure and uncorrupted;
it alſo renders the Water more denſe or heavy,
and confequently better fuited to ſuſtain ſhips
of large burthen, and promotes the purpoſes of
navigation by being lefs liable to freeze, and
thereby prove inacceffible, and alfo to nourish a
variety of beings whofe native Element is the
Sea, and laftly, to fertilize lands by the falutary
effects of its faline vapours, and the qualities
that are extracted from its extraneous matter,
as manuré.
Lady
On Mountains, &c.
311
Lady M. You have given me fo clear an ac-
count of the Sea, that next Summer, when I
go to Weymouth, I fhall view it with peculiar
pleaſure and attention.
Ment. There yet remains many wonderful
properties for me to defcribe, in particular, ref-
pecting fubmarine vegetative productions, which
include Plants, Shrubs, and Trees, that grow
under the Sea, or on its immediate coafts.
Lady L. I have frequently feen Sea Weeds
of varied defcriptions, and have had many in
my poffeffion.
A
Ment. The Submarine vegetables are di-,
vided into three claffes, Plants, Arborefcent
Shrubs, or Corallines, and Coral Trees; as
the hard fubftance of which thefe productions
confift is called Coral. The texture and forin
of theſe varied objects are fo well known, I
ſhall not attempt to defcribe or enumerate
them; they differ very effentially in their ori
gin from the nature of terreftrial Plants, which
are germinated from a feed, and derive their
nouriſhment from the Earth by means of their
root and fibres, whilſt Sea Plants are fixed by a
broad bafis to the hard furfaces of Stones and
Rocks, and appear to receive their nutriment
and growth through the general component parts
of
312
On Mountains, &c.
of their bodies, and have no Seeds or Flowers.
As theſe plants are confiderably lighter than
Sea Water, they are confequently fupported by
it; and when by accident they are torn from
the ſubſtance to which they adhere, they fwim,
and are waſhed on fhore by the furges of the
Sea, and by being caft on the Coaft, afford im-
provement to the curious, benefit to thoſe em-
ployed in agriculture, and alfo in glafs manu-
factories, by burning the Sea Weeds for the
falt their afhes contain.
Lady M. I never before knew that Coral is
a Sea production.
Ment. The fpecimens you have feen, dif-
fer very effentially from the Corallines I have
juſt mentioned. The Coral you admire is a
vegetable Spar or Cryſtal, that the Earth pro-
duces, which is nourished by Sea Water; it
chiefly grows upon Rocks in various fpecies,
forms, fizes, and colours; the moſt perfect fort
of Coral is the red and white, as the black Co-
ral is in fact only a fubmarine wood. Befides
this genuine kind of Coral, there is a ſpurious
fpecies, called Madrepore, of which ther eare
fome in Canada of a lively blue hue. The
form and growth of Sea Plants are a ſtriking
proof of Divine fkill, and that the motion of the
Water
On Mountains, c.
313
Water extends to a confiderable depth; as thoſe
Plants which grow at the bottom of the Sea,
and at a great diftance from its furface, gene-
rally are of a flat form, in fome degree refem-
bling the conftruction of a fan, but not with
lateral branches like Trees, which formation
is peculiarly adapted to enable them to encoun-
ter the flux and reflux of the tide, without fuf-
taining any injury as to their figure or duration.
In the most profound abyffes of the depths of
the Ocean, Mr. Ray thinks it highly probable
there are neither Plants nor Fifhes, as their re-
mote fituation from the external furface would
render the portion of air, and the ſupply of in-
fects as food, inadequate to the purpoſes of ex-
iftence; and from the influence of their aquatic
element, Submarine Plants are of a dufky olive
colour, but never of a vivid green hue, like ter-
reſtrial vegetables; though many are of the moſt
delicate texture, and poffeffed of inherent beau-
tiful colours and to the variety I have already
enumerated, the Sponges which are common
in uſe, conſtitute a diftinct order of Submarinc
Vegetables.
:
Lady L. Do we not derive feveral advan-
tages by being inhabitants of an Iſland?
P
Ment.
314
On Mountains, &c.
Ment. We are benefited very effentially by
our infular fituation; in the firſt inſtance, by
the extent of Trade and Commerce, and alſo
by the conſequent influx and connection with
the most diftant regions, which accumulate
wealth, and tend to the general civilization of
the inhabitants of fuch a diftinguiſhed Ifle, bleft
by local advantages, and protected by lenient
laws adminiſtered with impartial justice. Not-
withſtanding you are well informed refpecting
the principal Illands in the different parts of the
Globe, I must add fome remarks refpecting the
New Iſlands that are fometimes produced by
the fudden operation of fubterranean Fires, or
by the more gradual procefs of fediments of
Water, theſe are but rare; but there are many
New Ilands occafioned by the Mud, Sand,
and Earth, which the Rivers or the Sea convey
to different parts of the Globe; the Sea alfo by
retiring from certain Coafts, and by encroach-
ing on others, and thereby covering the loweſt
part of the ſurface, by that means produces the
fame effects; and it is obfervable, there are but
very few iſlands in the middle of the Sea, but
chiefly near to continental countries, where they
were probably formed, either by the retreat or
approach of that irreſiſtible body of Water. I
fhal
کر
On Mountains, e.
315
ſhall now cloſe my account of Iſlands; I hope
you are truly fenfible of the individual and gene-
ral bleffings we enjoy, as natives of a land en-
lightened by Christianity, refined by the pro-
grefs of Arts and Sciences, and protected by a
wife Conſtitution, which is the bafis of Civil
and Religious permanent fecurity.
Lady M. It is impoffible for me to exprefs
my gratitude for the difpenfation of the blef-
fings you have enumerated; and I regret the
probability of your having completed your ac-
count of the Sea.
Meat. Concerning its general properties,
I have little more to obferve, but as I have en-
deavoured to explore its most profound receffes
and its abundant productions, it is in fome
degree neceflary for me to make fome remarks
concerning its various Inhabitants. In this
refearch, Fithes are the first clafs of beings, that
preſent themſelves to our view, which may be
thus diftinguithed; firft of the cetaceous kind
that includes the Whale in all its varieties, the
Dolphin, the Grampus, and the Porpoife, which
in fome degree refemble Quadrupeds in their
internal construction and habitudes, and cannot
fubfift under the water, for any confiderable
length of time; the next tribe are of the Car-
tilaginous
P 2
316
On Mountains, &c.
tilaginous kind, which have cartilages or grif
tles inftead of bones, and are fubdivided into
the Shark, and Ray kind. The next are the
fpinous kind of Filhes, or thofe of the bony
kind, which are fo numerous, they are fome-
times divided into a variety of claffes, to denote
their feveral properties, fome of which poffefs
a poifoncus quality. The laft order is Shell
Fish, which are thus ranked. First the cruf-
taceous kind, fuch as the Lobfter, Crab, Tor-
toife and Turtle; next the teftaceous fpecies,
the fhell of which may be confidered as its ha-
bitation as thefe fubjects may be traced in
infinite variety, as the means of giving you a
clear idea of their feveral generic diftinctions,
I fhall inform you that Ariſtotle divided them
in the following manner. The univalve, or
turbinated, which conſiſt of one piece like the
fhell of a fnail; fecondly the bivalved, confifting
of two pieces united by a kind of hinge, as an
Oyſter; and laſtly the multivalve, confifting of
more than two pieces, many of which tribe are
formed of a number of parts. All theſe vari-
ed ſpecies are found in different depths of the
Sea, and are valuable in proportion to their
beautiful, or rare properties.
Lady
On Mountains, &c.
317
Q
Lady L. A friend of mine gave me a col-
lection of fhells which I greatly eſteem, I be-
lieve he brought them from the Eaſt Indies:
Pray Mentoria, are not Pearls produced from
fome kind of Shell Fiſh?
Ment. The moſt rare and beautiful ſpecies
of Shells are brought from Eaſtern regions;
your prefent will appear doubly valuable, if you
not only admire it for the varied exterior elegance
of its feveral fpecimens, but alſo reflect
that the moft minute article has been the abode
of fome animated being. Pearls, as you rightly
imagine, are the production of Shell Fish, ma-
ny of which are found to contain Pearls, but
particularly that fpecies which has obtained
the name of the Pearl Oyſter; it has a large
ſtrong ſhell of a whitish hue, exteriorly of a
wrinkled rough texture, and in the infide of a
filver colour and finooth quality, from which
what we call the Mother of Pearl is produced.
The Oysters which contain the fuperior kind of
Pearl, are principally found in the Gulph of
Ormus, and feveral parts in the East Indies;
though there are Pearl Fitheries eſtabliſhed in
various places in the Alian and American feas,
and theſe valuable Oytiers are procured by a re-
gular procefs of diving for them to a confidera-
P 3
ble
}
318
On Mountains, &c.
ble depth, which is effected by the efforts of
fkill, undaunted by imminent danger. Pearls,
which are eſteemed as an elegant coftly orna-
ment, next in degree to precious ftones, are
nothing more than a preternatural excrefcence of
the Fiſh, probably not the effect of diſeaſe,
but only produced by fome extraordinary means.
from the fame matter that conftitutes the fhell.
}
Lady L. It is extremely kind of you to give
us fuch a particular account of thofe things
which we ſo often view, but have never ſeriouſly
regarded.
Ment. I have endeavoured to defcribe the fe-
veral kind of Fifhes, which you must ftrive by
fome other means to be circumftantially ac-
quainted with. Fifh in general may be regard-
ed as inhabitants of the Sea; though fome par-
ticular ſpecies live in freſh Waters, and others
migrate annually to Rivers to depofit their
ſpawn, which could not be ſo ſafely diſpoſed of
in the tempestuous depths of the Ocean. The
conftruction of Fishes is admirably adapted to
the peculiar fituation; the air-bladder with
which they are almoſt univerſally endued, ena-
bles them to refpire in an element apparently un-
congenial to that purpoſe. Their fins, and tail
are formed of a texture, to accelerate their pro-
grefs,
On Mountains, c.
319
greſs, and keep their body in proper equilibrium
and due courſe: and their great fecundity is
wifely ordained for the preſervation of each ſpe-
cies, as they are not only food for Man, but
the objects of prey for all fuperior kinds of
Fishes, which make regular depredations on
each other, and fubfift by that means, and on
the infects and plants the Sea produces.
Lady M. Are not Fishes a very wonderful
tribe of animated beings?
Ment. Without doubt, and diſtinguiſhed by
feveral characteriſtic marks, as well as by great
inequalities in their dimenfions, fome being fca-
ly, others covered with fkins of a fmooth furface,
and many defended by a coat of a hard, yet often
of a brittle quality: they are alſo ſubject to great
variations in fize, fome being of a large magni-
tude and others diminutive; and great numbers.
fit for food, but fome particular ſpecies of a
poiſonous nature. Beſides Fiſhes, there is ano-
ther kind of animals whofe proper element is
the Sea; fuch as Seals in their ſeveral varie-
ties, the Walrus and the Manati: theſe crea-
tures all form a diſtinct claſs in the ſcale of be-
ings by being compounded of heterogenous
qualithich render them, not withitanding
they are animals, nearly allied to the Cetaceous
tribe
320
On Mountains, Sc.
tribe of Fishes; as the Seal and Walrus have
a kind of members refembling four feet, confe-
quently approach nearer to quadrupeds than to
Cetaceous Fishes; but the Manati by having
only two fore feet, refembles the Cetaceous
kind more than quadrupeds. The Seals, and
Walrus alfo, from the peculiar conftruction of
their heart, can fubfiit either on Water or
Land: but the Manati fpecies cannot properly
be termed amphibious, as they never entirely
leave the water, but only advance their head to
the fhore to eat grafs and herbage: they are
fometimes found in Salt Water, but chiefly in
Creeks and Rivers near the Sea, but not very
far from land.
Lady L.
What do you mean by am-
phibious animals, my dear Mentoria: is the
Sea Bear of that quality?
Ment. The Sea Bear, which is often called
the White Bear, the Polar Bear, or the Sea Bear,
is not of that clafs, as it only lives occafionally
on the fields of ice in the frozen Seas, and at
other times on land.
The term amphibious
fuch animals as are con-
is properly applied to
ftructed to breath the air, but pafs the greateft
part of their time in the Water, as that ele-
ment affords them the moſt food, fuch as the
Frog,
On Mountains, &c.
321
}
Frog, Otter, Beaver, &c. &c. and
ewife
to feveral ſpecies of plants as grow either on
Land or in the Water, viz. the Alder, Wil-
low, &c. &c.
Lady Mary. I fear you have finished your
account of the Sea, its productions and nu-
merous inhabitants; and I anticipate with
much concern that your inſtructions on Natural
Philofophy are nearly terminated.
Ment. There yet remains another branch.
of exiſtence immediately connected with the
Sea, called Zoophytes, that are not produced by
the ufual courſe, but by diffection; as, if they
are divided into feveral parts, each becomes in
due time a perfect animal; ſuch as the Polypus,
or Polypes, which according to their varied
fpecies have different names. There is alfo
another wonderful genus of Sea animals that ap-
pear to be a kind of animated plant, and grow
upon the furface of Rocks, Pebbles, Stones,
&c. to which they fo firmly adhere, it is with
difficulty they are ſeparated without effential in-
jury to their texture. They are of various fpe-
cies, forms, fizes, and different colours, one
in particular, is called the Sea Anemone, and
others reſemble young Aloe leaves, and many
when
322
On Mountains, &c.
when expanded, appear like Flowers beautifully
variegated.
Lady. L. How can thefe productions that
reſemble flowers, be animals?
Ment. It is evident they are poffeffed of
animal powers, from the motions and actions of
their bodies; and they are afferted to be very
expert in catching and devouring their prey;
fuch as Crabs, &c. &c. To this wonderful
clafs of beings, the Polypus, the Earth Worm,
and all the varieties of the Sea Nettles, properly
belong, and very probably alfo, thofe that pro-
duce Coral, and Sponges.
Lady M. The next time that I am on the
Sea coaft, I will endeavour to get fome of thofe
Animated Plants; as I fhall take great pleafure
in fuch curious Phænomena.
Ment. I have confidered the Earth, first as
a Planetary Orb, performing its annual courfe
round the Sun; fecondly, as a Terraqueous
Sphere compoſed of Land and Water; and
laftly, as a Congregated Globe, inhabited by
myriads of beings endued with powers ſuited to
their ſtate of exiflence. On a philoſophical
furvey of the operations of Nature, it appears
evident, that the Deity in a variety of inftances,
gradually unfolds his divine attributes in the ge-
neral
On Mountains, &c.
323
neral ſyſtem of the Univerfe. In the animal
claffes, the gradation is progreffive from Man
to the Ape; from the Ape to Quadrupeds;
from Quadrupeds to Cetaceous Animals; and
from thoſe tribes to Birds, Fishes, and Reptiles.
By extending this reſearch ſtill further, we may
clearly trace the degeneration from Reptiles to
Infects; from Infects to Worms; from Worms
to Zoophytes; and from Zoophytes to Plants.
In each variation the declenſion is marked by a
combination of qualities which have a kind of
analogy, and form a regular thade that connects
every genus into a ſyſtem of perfect order, and
organic harmony.
Lady M.
I had no idea there were fuch
fimilarities and connections as you have fpeci-
fied; but am now clearly convinced, that every
part of the Creation abounds with perfections,
which are not fufficiently the object of atten-
tion.
Ment. The Univerfe proclaims its Maker's
praiſe, by the various proofs it exhibits of Di-
vine Excellence; bleffings which are diffufively
diſpenſed, though but imperfectly eſtimated or
acknowledged. Our gratitude thould be pecu-
liarly excited when we reflect, that in the gene-
ral ſcale of Being, the Human Race hold the
firſt
324
On Mountains, c.
firſt claſs. This fuperiority arifes wholly from
their intellectual faculties; as feveral inferior
fpecies exceed them in ftrength and magnitude,
and by the operations of inftinct, equal them
in ingenuity, and many other valuable qualities;
therefore their pre-eminence alone originates
from the poffeffion of Reafon, and that immortal
pure intelligence of Mind that render them
capable to judge between Good and Evil, and
to contemplate the works of their Creator.
The general fubordination that may be deline-
ated in all parts of Animated Nature, as ne-
ceffary to the exiſtence and welfare of every
member of each fpecies, infpires a contempla-
tive mind with acquiefcent reſignation reſpect-
ing the feveral ftations and allotments in life,
which conſtitute collateral degrees, conform-
ing to thofe in the Animal Genera, as relative
to diſtinctive qualities. Thofe properties which
exalt Human Nature to its greateſt poſſible de-
gree of perfection, are univerfally diſpenſed;
fuch as Reaſon, and the various operations of
Intellect; whilft partial diftinctions, as ele-
vated Rank, Riches and Power, are only oc-
cafionally beſtowed to fulfil the general pur-
poſes of order, requifite for the benefit of the
Community; as individually, thofe poffeffions
neither
On Mountains, &c.
325
neither enfure happineſs nor prove an exemp-
tion from the various conflicts and viciffitudes
of temporal events. On an impartial retrof-
pect of Human Frailty, and a juſt ſtatement
of Divine Mercies and difpenfations, thoſe
muſt be confidered as ineftimable that deliver
Mankind from the dominion and penal confe-
quences of Sin, by the perfect atonement of
our bleffed Redeemer! Let theſe ſublime truths
enlighten your minds, and produce humility in
its moſt comprehenfive and refined fenfe, which
in he higheſt ſtation, is not inconſiſtent with
dignity of character; endeavour by your exam-
ple and precepts, to ftem the current of popu-
lar error in all matters that operate againſt the
fuggeſtions and decrees of Moral Principles.
By your general conduct evince an uniform de-
vout reverence for the Chriſtian Religion, Ho-
ly Ordinances, and Sacred things; but above
all, as the ultimate criterion of your duty, che-
rifh an entire, unlimited confidence in the Pro-
mifes of God, and the efficient Protection of his
Divine Providence!
FINIS.
DIRECTIONS TO THE BINDER.
The GLOBE to face the Title.
Table of Diameters and Distances of PLA-
NETS, to face Page
The NORTHERN CELESTIAL
--28
HEMI-
SPHERE, and the SOUTHERN CELESTI-
AL HEMISPHERE, to be placed between
pages 54 and 55, on a Guard.
Lift of CONSTELLATIONS & STARS to face p. 80
ERRAT A.
Page 6. Line
5. for is, read in.
8.
58.
66.
70.
145.
167.
244.
20. for bid, read hidden.
19. for Plecades, read Pleiades.
27. for is, read are.
17. for Archemedes, read Archimedes.
8. for is, read are.
13. for requires, read require.
9. for furrounds, read Jurround.
249. 18, for Parafclena, read Parafelena..
A 504655