bigram

This is a table of type bigram and their frequencies. Use it to search & browse the list to learn more about your study carrel.

bigram	frequency
solar system	1224
milky way	625
let us	507
naked eye	440
one hundred	388
heavenly bodies	375
years ago	372
fixed stars	367
united states	334
sir william	317
double stars	314
astronomer royal	287
per second	259
one side	258
sir john	253
thousand miles	246
royal society	241
two stars	237
new york	233
two hundred	226
full moon	218
miles per	217
royal observatory	209
four hours	206
million miles	206
many years	198
new star	195
take place	195
john herschel	194
total eclipse	194
william herschel	192
thousand years	190
three hundred	188
straight line	184
hundred miles	183
much less	183
hundred years	173
years later	172
present time	171
three years	170
solar spectrum	169
much greater	167
first magnitude	164
well known	161
magnitude star	161
great bear	158
one another	157
nebular hypothesis	157
southern hemisphere	157
minor planets	154
per cent	153
central mountain	153
pole star	151
took place	151
astronomical society	148
present day	145
celestial sphere	142
cubic miles	142
great britain	141
le verrier	140
mean distance	139
proper motions	137
double star	137
centrifugal force	136
variable stars	134
nautical almanac	133
dark lines	132
north pole	132
two years	132
every one	130
lick observatory	130
two bodies	130
one time	129
crown vo	128
tycho brahe	128
five years	127
much larger	127
prime meridian	127
stellar universe	126
bright lines	125
bright stars	125
long time	124
greenwich observatory	123
great nebula	123
first place	121
taken place	121
northern hemisphere	120
right ascension	120
tells us	119
may th	118
bright star	118
observations made	118
right angles	118
zodiacal light	117
three times	117
thousand times	116
great number	116
royal astronomical	115
new moon	115
different parts	115
proper motion	114
every part	114
inch telescope	114
magnifying power	114
great comet	113
great deal	113
june th	113
far beyond	112
planetary system	112
first time	111
de la	110
good hope	109
opposite side	108
four years	107
solar eclipse	107
powerful telescopes	107
great circle	107
astronomical observations	104
nineteenth century	104
one day	103
takes place	103
copernican system	103
five hundred	103
good deal	102
will see	101
will find	101
celestial bodies	101
feet high	101
revolve around	100
second magnitude	100
august th	99
animal life	98
solar heat	97
four times	96
short time	96
opposite direction	95
shall find	95
miss mitchell	95
focal length	95
one star	95
every day	94
greater part	94
much smaller	94
will show	94
straight lines	93
four hundred	93
lunar theory	92
small stars	92
revolving round	91
one direction	91
hundred times	91
shall see	91
comptes rendus	91
new planet	90
powerful telescope	90
great distance	89
july th	88
two thousand	88
transit instrument	88
far away	88
many times	88
million years	88
apparent size	87
now known	87
nearly equal	87
nebulous matter	87
shooting stars	87
mount wilson	87
set forth	87
tell us	86
sir george	86
professor newcomb	86
years old	86
twenty years	86
thirty years	86
give us	85
november th	85
meteoric stones	85
square miles	85
local time	84
periodic time	84
either side	83
transit circle	83
close together	82
nearly circular	82
one point	81
revolving around	81
long ago	81
will appear	81
one second	81
three days	81
alpha centauri	80
faint stars	80
enable us	80
great pyramid	80
spiral nebula	80
much light	80
large number	80
ursa major	79
ten years	79
turned towards	79
fifty years	79
several years	79
ten times	78
six years	78
universal gravitation	78
human race	78
heavenly body	78
fixed star	78
hundred thousand	77
british association	77
great telescope	77
great work	77
may well	76
five miles	76
reflecting telescope	76
small telescope	76
revolution around	76
six months	76
two hours	76
every year	75
every direction	75
sir isaac	75
one thousand	74
one half	74
south pole	74
will take	74
lunar surface	74
chapter ii	74
left behind	73
almost exactly	73
brightest star	73
may say	73
whole mass	72
third magnitude	72
towards us	72
miles across	72
gives us	72
two planets	72
lord rosse	72
new stars	72
times less	72
miles long	72
like manner	71
miles away	71
trinity college	71
harvard college	71
universal day	71
dear sir	71
almost every	70
one end	69
mean density	69
yerkes observatory	69
many others	69
three stars	69
vernal equinox	69
lunar crater	68
first sight	68
fifteen years	68
apparent diameter	68
sun will	68
middle ages	68
earth must	68
seven years	67
now know	67
star clusters	67
times greater	67
us now	67
white light	67
inches aperture	67
unaided eye	67
sixth magnitude	67
cambridge observatory	67
relative positions	66
will probably	66
organic life	66
chapter iii	66
photographic plate	65
little bear	65
several times	65
one degree	65
orion nebula	65
variable star	65
celestial objects	65
stellar system	65
two points	65
one part	65
never seen	64
solar surface	64
something like	64
will give	64
solid matter	64
taking place	63
red spot	63
will now	63
isaac newton	63
scientific men	63
two great	63
great interest	63
even though	63
polar caps	63
many cases	63
polar axis	63
planetary orbits	63
greatest density	63
large enough	63
three months	63
mare imbrium	62
cosmic matter	62
solar atmosphere	62
chapter iv	62
seven days	62
around us	62
forty years	62
one place	62
hundred feet	62
ten thousand	62
line joining	62
see plate	61
universal time	61
modern astronomy	61
may seem	61
much nearer	61
copernican theory	60
paris observatory	60
small bodies	60
already mentioned	60
foot telescope	60
greater distance	60
far greater	60
five degrees	60
sun must	59
four days	59
magnitude stars	59
revolve round	59
celestial equator	59
sir david	59
bright crater	59
one might	59
physical constitution	59
brightest stars	59
one may	59
temporary stars	59
ptolemaic system	59
modern times	59
astronomical instruments	59
first seen	59
th part	58
eight years	58
us suppose	58
hollow sphere	58
november meteors	58
large part	58
illustration fig	58
many stars	58
five thousand	57
five times	57
inch refractor	57
three hours	57
angular distance	57
see also	57
long period	57
professor young	57
various parts	57
less dense	56
may now	56
must therefore	56
aqueous vapor	56
refracting telescope	56
stars may	56
binary stars	55
royal vo	55
modern science	55
comparatively small	55
solar systems	55
great importance	55
revolves around	54
quite different	54
perihelion passage	54
will therefore	54
much like	54
miles high	54
square inch	54
object glass	54
magnitudes six	54
spectrum analysis	54
small star	54
young man	54
many millions	53
sir robert	53
every star	53
outer planets	53
ever since	53
common centre	53
next day	53
two centuries	53
attractive force	53
third law	53
see fig	53
twenty miles	53
present state	53
solar spots	53
five days	53
stars visible	52
mean temperature	52
inferior conjunction	52
polar regions	52
orbital motion	52
whole earth	52
tidal friction	52
one way	52
greater number	52
twelve hours	51
fourth magnitude	51
original nebula	51
already seen	51
sir norman	51
equatorial regions	51
even now	50
dark body	50
great majority	50
practical astronomy	50
six hundred	50
easily seen	50
least one	50
well seen	50
moon must	50
two days	50
june report	49
shows us	49
mural circle	49
question whether	49
must also	49
resisting medium	49
chapter vi	49
continuous spectrum	49
visible surface	49
nearest star	49
great planet	49
little doubt	49
totally different	49
last century	49
brighter stars	49
enables us	49
many thousands	49
star cluster	49
et seq	49
may also	48
carbonic acid	48
one planet	48
great astronomer	48
astronomical observation	48
six miles	48
large proportion	48
total eclipses	48
dark ring	48
crossley reflector	48
seventeenth century	48
astronomical work	48
thousandth part	48
radius vector	48
evening star	48
apparent motion	48
planet mars	48
living things	48
distance apart	48
great discovery	48
central body	47
one occasion	47
three miles	47
four miles	47
will make	47
multiple stars	47
great extent	47
foot reflector	47
opposite sides	47
reversing layer	47
must always	47
faint star	47
northern crown	47
six times	47
private history	47
six thousand	47
sun may	47
ten days	47
following year	46
canes venatici	46
reader will	46
large telescopes	46
three thousand	46
demy vo	46
solar corona	46
solar energy	46
first quarter	46
will enable	46
celestial body	46
good telescope	46
magnetic field	46
starry heavens	46
may see	46
telescopic power	46
planetary motions	46
directed towards	45
reflected light	45
will always	45
eleven years	45
whole system	45
initial meridian	45
small planets	45
put forward	45
outer edge	45
little less	45
mean time	45
spectral lines	45
stellar parallax	45
may take	45
solar eclipses	45
nothing else	45
mare serenitatis	44
nearly three	44
fifth magnitude	44
six feet	44
will continue	44
present century	44
chapter vii	44
fifty miles	44
great difficulty	44
long since	44
seven stars	44
christian era	44
north america	44
every point	44
march th	44
whole solar	44
temporary star	44
inferior planet	44
entirely different	44
feet long	44
human mind	43
larger planets	43
hundred millions	43
april th	43
average distance	43
physical astronomy	43
two parts	43
already referred	43
one year	43
ursa minor	43
naval observatory	43
might well	43
important part	43
good reason	43
thousand feet	43
line drawn	43
red star	43
old man	43
zodiacal constellations	43
put together	43
college observatory	43
intelligent beings	42
long enough	42
visible universe	42
must necessarily	42
hundred million	42
earth around	42
look like	42
professor pickering	42
four thousand	42
luminous matter	42
little crater	42
will come	42
high temperature	42
nearly half	42
great many	42
still greater	42
sometimes called	42
canis major	42
norman lockyer	42
schmidt shows	42
earth moves	41
planet must	41
planet saturn	41
bright ring	41
late professor	41
half times	41
sun spots	41
complete revolution	41
one thing	41
recent years	41
total solar	41
principal stars	41
new system	41
solar light	41
eight minutes	41
go back	41
stars forming	41
near enough	41
professor proctor	41
know nothing	41
attractive power	41
george airy	40
different times	40
planetary motion	40
high degree	40
four minutes	40
professor henry	40
stars whose	40
professor challis	40
meteoric matter	40
astronomical observatory	40
next year	40
neutral meridian	40
relative distances	40
another way	40
one case	40
per square	40
five minutes	40
two bright	40
long series	40
extra crown	40
one great	40
copernican doctrine	40
common center	40
red stars	40
de morgan	40
far less	40
eighteenth century	40
like ours	40
every night	40
ninth magnitude	40
will never	39
two minutes	39
natural history	39
binary systems	39
total number	39
short period	39
ever seen	39
moon will	39
may therefore	39
atmospheric pressure	39
much longer	39
will also	39
parallel lines	39
andromeda nebula	39
short distance	39
soon found	39
give rise	39
atmospheric conditions	39
may call	39
absolute temperature	39
periodic times	39
small part	39
may add	39
nearly two	39
nebular theory	39
small crater	39
william huggins	39
autumnal equinox	39
celestial motions	39
superior planets	39
lord kelvin	39
absolute zero	39
twelve years	39
philosophical transactions	39
days later	38
human eye	38
ten hours	38
liquid state	38
revolution round	38
many centuries	38
much attention	38
much time	38
telescope will	38
ten miles	38
tenth magnitude	38
just mentioned	38
large telescope	38
lead us	38
great telescopes	38
dark bodies	38
bright little	38
generally accepted	38
diurnal revolution	38
will become	38
reach us	38
sixty years	38
due south	38
nova persei	38
de revolutionibus	37
stars appear	37
two months	37
hydrogen lines	37
specific gravity	37
solar parallax	37
astronomical discoveries	37
french astronomer	37
philosophical society	37
two different	37
different kinds	37
axial rotation	37
planetary bodies	37
lick telescope	37
two miles	37
following letter	37
one hand	37
great part	37
professor adams	37
seven miles	37
grand duke	37
living creatures	37
four feet	37
minor planet	37
corona borealis	37
great planets	37
central mass	37
seven times	37
terrestrial magnetism	37
careful study	37
cosmical axis	37
small portion	37
passed away	37
national observatory	37
planet jupiter	37
stars will	37
spectroscopic binaries	37
many astronomers	37
equal times	37
anything else	37
th century	36
great variety	36
professor peirce	36
centuries ago	36
may perhaps	36
seven hundred	36
two opposite	36
hydrogen gas	36
now see	36
nearly one	36
four satellites	36
chapter viii	36
summer solstice	36
civil war	36
component stars	36
nearest approach	36
inner edge	36
intense heat	36
small craters	36
first discovered	36
may appear	36
whole surface	36
apparent movements	36
scientific world	35
globular clusters	35
last night	35
central sun	35
perhaps even	35
leads us	35
still less	35
given us	35
sixty miles	35
greenwich time	35
canis minor	35
lunar eclipse	35
december th	35
scientific work	35
whole world	35
four stars	35
great circles	35
first step	35
interesting objects	35
different planets	35
holy office	35
different places	35
planet venus	35
half years	35
almost entirely	35
many miles	35
half hours	35
magnitudes five	35
opposite directions	35
different observers	35
low sun	35
nine years	35
must remember	35
much better	35
heat received	35
highest degree	35
mount hamilton	34
may find	34
solar nebula	34
minute stars	34
century ago	34
distant objects	34
inch glass	34
two large	34
greatest elongation	34
best known	34
chemical elements	34
coast survey	34
revolves round	34
smaller ones	34
become visible	34
years since	34
infinite space	34
father secchi	34
eight times	34
every side	34
fraunhofer lines	34
mr peacock	34
inner slope	34
lowell observatory	34
stellar spectra	34
magnifying powers	34
two lines	34
per hour	34
small fraction	34
various planets	34
diurnal motion	34
miles deep	33
eighth magnitude	33
mare crisium	33
fairly well	33
brother william	33
large scale	33
five hours	33
right hand	33
clear night	33
already described	33
anything like	33
solid body	33
stars near	33
inch reflector	33
two distinct	33
ninety degrees	33
general strachey	33
david gill	33
repulsive force	33
thousand stars	33
individual stars	33
must now	33
per minute	33
great discoveries	33
comparatively near	33
morning terminator	33
caroline herschel	33
whatever may	33
motion round	33
mutual attraction	33
will pass	33
one revolution	33
may possibly	33
bright enough	33
place among	33
eight days	33
western horizon	33
certain extent	32
early part	32
dusky ring	32
central peak	32
every thing	32
great mass	32
best seen	32
good fortune	32
magnetic needle	32
celestial phenomena	32
circle round	32
rotary motion	32
see whether	32
several days	32
whole universe	32
certain stars	32
william thomson	32
already stated	32
sidereal system	32
highly probable	32
two suns	32
different distances	32
curious fact	32
rotation period	32
lunar craters	32
physical conditions	32
elliptic orbit	32
greatest distance	32
dark spots	32
star will	32
partial eclipse	32
la rue	32
inferior planets	32
six days	32
human life	32
latter part	32
longitude deg	32
several planets	32
last year	32
eight thousand	32
chapter ix	32
two others	32
alvan clark	32
major axis	32
vs vf	32
six hours	31
twenty minutes	31
distant stars	31
material substance	31
central portion	31
small one	31
brought together	31
much heat	31
reflecting telescopes	31
low power	31
last quarter	31
civil day	31
large one	31
equal areas	31
radiant point	31
solar disk	31
two feet	31
new england	31
make one	31
nearly feet	31
meridian circle	31
much farther	31
telescopic stars	31
professor ball	31
south america	31
living organism	31
photographs taken	31
earth may	31
every revolution	31
eastern horizon	31
set aside	31
new world	31
two men	31
base line	31
shortly afterwards	31
several hundred	31
certain amount	31
old age	31
somewhat similar	31
acid gas	31
gold medal	31
outer ring	31
rudolphine tables	31
natural philosophy	31
harvard observatory	31
professor barnard	31
every case	31
human intellect	31
yet another	30
later years	30
apparent motions	30
planet will	30
must go	30
great distances	30
miles wide	30
th magnitude	30
favourable conditions	30
careful examination	30
another planet	30
vegetable life	30
extremely small	30
young men	30
orbit round	30
numerical lunar	30
meteoric shower	30
one knows	30
superior conjunction	30
miles apart	30
seventh magnitude	30
present condition	30
unknown planet	30
thirty miles	30
also called	30
one million	30
two observers	30
considerable distance	30
still remains	30
whole heavens	30
might almost	30
aqueous vapors	30
central position	30
stars composing	30
recent times	30
given rise	30
last two	30
little planet	30
mountain ranges	30
du monde	30
standard time	30
many instances	30
interplanetary space	30
solid bodies	30
one third	30
past ages	30
lunar atmosphere	30
coma berenices	29
dark side	29
planet uranus	29
closely associated	29
seven degrees	29
million times	29
circular motion	29
equal parts	29
aurora borealis	29
ever made	29
eighteen years	29
white spots	29
heat produced	29
simon newcomb	29
aqueous vapour	29
astronomical science	29
new astronomy	29
still farther	29
cape observatory	29
robert ball	29
star alpha	29
high tide	29
observer will	29
inverse square	29
us consider	29
may suppose	29
southern cross	29
glowing gas	29
greenwich observations	29
whole sky	29
fainter stars	29
three feet	29
dark line	29
lunar mountains	29
two kinds	29
planetary systems	29
great men	29
three bodies	29
nineteen years	29
new method	29
great advantage	29
upper end	29
san domingo	29
oceanus procellarum	29
whole number	29
night sky	29
star near	29
astronomical knowledge	29
dense atmosphere	29
internal heat	29
reflected sunlight	29
large portion	29
white stars	29
mean distances	28
one will	28
may exist	28
transit room	28
annual motion	28
well worth	28
two small	28
ring system	28
brilliant white	28
solar activity	28
just described	28
doubtful whether	28
will fall	28
planetary nebula	28
every twenty	28
magellanic clouds	28
generally believed	28
yale college	28
annual parallax	28
nearly central	28
smithsonian institution	28
exceedingly small	28
volcanic action	28
seventy years	28
lunar day	28
professor newton	28
given time	28
even one	28
material universe	28
magnitudes four	28
now generally	28
much brighter	28
eight miles	28
close double	28
george biddell	28
new observatory	28
sixteenth century	28
many things	28
great numbers	28
wilson observatory	28
southern horizon	28
show us	28
looks like	28
far back	28
percival lowell	28
may still	28
feet deep	28
earth will	28
outer slope	28
nearest fixed	28
many persons	28
rapid rotation	28
three bright	28
glass will	28
astronomical research	28
empty space	28
winter solstice	28
astronomical discovery	27
made known	27
first point	27
six inches	27
told us	27
long way	27
henry draper	27
solid crust	27
next chapter	27
will serve	27
different points	27
chapter xii	27
might expect	27
professor langley	27
every reason	27
modern astronomers	27
round numbers	27
past history	27
american astronomer	27
orbital revolution	27
stars must	27
twenty times	27
october th	27
may fairly	27
great size	27
diffused light	27
forty miles	27
chief stars	27
much interest	27
fifty thousand	27
five feet	27
may make	27
sir james	27
stars within	27
carried round	27
two million	27
meteoric masses	27
move round	27
far enough	27
single star	27
southern fish	27
hundred proofs	27
polar diameter	27
february th	27
radiant heat	27
turned toward	27
one peak	27
varies inversely	27
quite possible	27
chapter xi	27
gamma draconis	27
dry land	27
large crater	27
carried along	27
many illustrations	27
new ones	27
north star	27
might say	27
upper part	27
many thousand	27
nebulous mass	27
six weeks	27
work done	27
come back	27
matter composing	27
large ring	27
fixed point	27
powerful instruments	27
light reflected	27
almost impossible	27
large extent	27
one hour	27
still remain	27
retrograde motion	26
thirty times	26
count lewenhaupt	26
telescopic objects	26
true one	26
rapid motion	26
magnetic storms	26
one body	26
another star	26
two principal	26
big dipper	26
solar rays	26
general law	26
special attention	26
due north	26
accurate observations	26
last chapter	26
low temperature	26
say nothing	26
will go	26
brilliant star	26
made many	26
central hill	26
two satellites	26
now proceed	26
terrestrial paradise	26
come within	26
certain distance	26
many hundreds	26
morning star	26
also found	26
first two	26
hundred pounds	26
may easily	26
human knowledge	26
two places	26
turned round	26
great accuracy	26
one particular	26
ring nebula	26
mutual attractions	26
us see	26
make use	26
nearest stars	26
left hand	26
every possible	26
photograph taken	26
individualized substance	26
case may	26
knew nothing	26
small circle	26
go round	26
solid earth	26
vast number	26
scientific research	26
far removed	26
nearly every	26
almost certain	26
remarkable fact	26
earth revolves	26
without much	26
superior planet	26
due time	26
hooker telescope	26
otto struve	26
mare nectaris	26
favorable circumstances	26
sun moves	26
well defined	26
will occur	26
gaseous matter	26
nearly parallel	26
physical condition	26
spectroscopic observations	26
georgium sidus	26
planets must	26
might seem	26
major planets	26
one foot	26
hollow centre	26
two components	25
solar rotation	25
smaller one	25
first attempt	25
every time	25
chemical constitution	25
every particle	25
though perhaps	25
one inch	25
mare humorum	25
periodic comets	25
even greater	25
space occupied	25
multiple star	25
twenty feet	25
meteoric bodies	25
gave rise	25
costa rica	25
already remarked	25
first satellite	25
planets move	25
large bright	25
solar disc	25
moon may	25
first day	25
outer space	25
admiral smyth	25
east longitude	25
many people	25
many hours	25
red end	25
among astronomers	25
regular intervals	25
angular diameter	25
first law	25
turned away	25
us take	25
much lower	25
brought forward	25
two classes	25
violet rays	25
bright line	25
one focus	25
glowing hydrogen	25
much broken	25
one else	25
constantly increasing	25
might easily	25
early days	25
inner half	25
first thing	25
widely different	25
freezing point	25
will ever	25
popular astronomy	25
bright central	25
seems probable	25
wide double	25
observed facts	25
planet mercury	25
yet even	25
considerable portion	25
next morning	25
little ring	25
planet neptune	25
great measure	25
water vapor	25
nearly four	25
infinite number	25
one night	25
stony meteorites	25
astronomical telescope	25
following table	25
three inches	25
three different	24
vs bm	24
polar snows	24
solar cluster	24
close approach	24
often called	24
meteoric showers	24
general rule	24
northern heavens	24
polar snow	24
considerable number	24
west longitude	24
telescopic object	24
true nature	24
various kinds	24
lunar eclipses	24
larger star	24
many respects	24
galileo galilei	24
never see	24
important question	24
intimately connected	24
large masses	24
central part	24
chapter xiii	24
nearly twenty	24
snow caps	24
great ring	24
way across	24
revolved around	24
great amount	24
physical science	24
personal equation	24
widely separated	24
three million	24
two inches	24
farther away	24
six minutes	24
far apart	24
powerful enough	24
dark stars	24
des sciences	24
three minutes	24
mean solar	24
relative position	24
various ways	24
falling stars	24
nearly twice	24
little star	24
celestial vault	24
twenty degrees	24
late years	24
must pass	24
certain degree	24
planets revolve	24
southern pole	24
among us	24
different colors	24
comet appeared	24
different portions	24
earth might	24
inch achromatic	24
may even	24
new planets	24
less brilliant	24
brings us	24
astronomical journal	24
particular star	24
second law	24
intensely heated	24
celestial object	24
conspicuous object	24
apparent magnitude	24
exactly equal	24
planets revolving	24
still another	24
george iii	24
much higher	24
commander sampson	24
doubt whether	24
sun rises	24
smaller stars	24
great length	23
three weeks	23
visible stars	23
many different	23
average density	23
will move	23
magnetic storm	23
every second	23
three seconds	23
one evening	23
astronomische nachrichten	23
professor lowell	23
years afterwards	23
well acquainted	23
violet end	23
already known	23
thousand millions	23
concave mirror	23
central parts	23
brilliant stars	23
will remain	23
two sides	23
special interest	23
great problem	23
still higher	23
might possibly	23
many months	23
latter case	23
thirty feet	23
mean diameter	23
ten minutes	23
miles distant	23
vastly greater	23
binary system	23
get rid	23
chromatic aberration	23
holy scriptures	23
lunar tables	23
southern heavens	23
great red	23
outer surface	23
slightly different	23
sixteen years	23
excessive heat	23
magnetic observations	23
large comet	23
extremely difficult	23
general appearance	23
recent observations	23
lower part	23
different periods	23
smaller star	23
fifteen degrees	23
circular orbits	23
another time	23
common sense	23
slow motion	23
earth rotates	23
apparent movement	23
hundredth part	23
electrical repulsion	23
johns hopkins	23
enormous distance	23
first view	23
within reach	23
eighty degrees	23
solar radiation	23
surface must	23
near approach	23
pretty well	23
great lick	23
express train	23
pure mathematics	23
strong enough	23
elapsed since	23
annular eclipse	23
relatively small	23
moon revolves	23
spectral type	23
miss herschel	23
spot period	23
earliest times	23
photographic plates	23
solar constant	22
light coming	22
two equal	22
radial velocities	22
another great	22
also known	22
similar manner	22
near together	22
planets may	22
less conspicuous	22
gaseous envelope	22
best advantage	22
least three	22
body revolving	22
considerably less	22
generally known	22
distinctly visible	22
eighteen miles	22
toward us	22
mare nubium	22
exactly opposite	22
moving towards	22
piazzi smyth	22
old friend	22
larger one	22
great man	22
every way	22
telescopic comet	22
rising sun	22
actual distance	22
remained visible	22
millionth part	22
deep crater	22
little way	22
many ages	22
fall towards	22
greatly increased	22
cosmic time	22
ancient times	22
will soon	22
elliptic path	22
soon became	22
small telescopes	22
inner ring	22
miles broad	22
every hour	22
various forms	22
star may	22
hardly possible	22
first suggested	22
giordano bruno	22
fifteenth century	22
system must	22
infernal regions	22
far distant	22
axial revolution	22
one must	22
observer may	22
regular solids	22
crape ring	22
bright streaks	22
must take	22
four months	22
black spot	22
great care	22
stellar systems	22
equatorial diameter	22
present form	22
may become	22
magnetic observatory	22
quite certain	22
one man	22
first astronomer	22
will perhaps	22
first half	22
carefully observed	22
might find	22
many places	22
next return	22
though still	22
little dog	22
seen without	22
different positions	22
become acquainted	22
must look	22
every month	22
turn round	22
plant life	22
seven planets	22
comets whose	22
every kind	21
metallic vapors	21
conspicuous stars	21
take part	21
apparent distance	21
radiant energy	21
de vico	21
vertical circle	21
found among	21
main body	21
daily life	21
first discovery	21
red light	21
four degrees	21
th november	21
five planets	21
great difference	21
starting point	21
first made	21
international conference	21
see nothing	21
great globe	21
results obtained	21
astronomical world	21
solar equator	21
north latitude	21
stand still	21
well observed	21
well enough	21
imaginary line	21
must make	21
proctor says	21
different kind	21
polar cap	21
total phase	21
must revolve	21
direct observation	21
whose name	21
three degrees	21
curiously enough	21
practical astronomer	21
greater velocity	21
diurnal rotation	21
just outside	21
sea level	21
general character	21
bad weather	21
quite recently	21
low ridges	21
spherical aberration	21
years past	21
must exist	21
exact astronomy	21
mean motion	21
years previously	21
surface features	21
hunting dogs	21
august meteors	21
spherical form	21
little attention	21
know whether	21
highly heated	21
will prove	21
great heat	21
may look	21
general reader	21
earth round	21
now call	21
turns round	21
might take	21
lower end	21
sun appears	21
rapid changes	21
much pleased	21
least two	21
every planet	21
two hemispheres	21
almanac office	21
times farther	21
living organisms	21
vs sbm	21
feet per	21
small amount	21
liquid matter	21
optical power	21
almost always	21
telescopic observation	21
kinetic theory	21
several thousand	21
now come	21
one satellite	21
mathematical astronomy	21
already explained	21
immediate neighborhood	21
nebulous light	21
twentieth century	21
one quarter	21
new edition	21
spring tides	21
directly towards	21
must either	21
made use	21
large amount	21
high magnifying	21
half century	21
earth moved	21
setting sun	21
telescope may	21
little stars	21
nearly miles	21
lunar globe	21
well established	21
months later	21
two smaller	21
somewhat larger	21
report states	21
first lord	21
determine whether	21
almost certainly	21
less bright	21
equally well	21
larger scale	21
celestial spaces	21
white star	21
dudley observatory	21
star gamma	21
fifty feet	21
drawings made	21
circle around	21
new theory	21
mare tranquilitatis	20
without form	20
ages ago	20
somewhat less	20
whose components	20
whole length	20
two lenses	20
first one	20
solar prominences	20
torrid zone	20
interesting object	20
real motion	20
certain conditions	20
small ones	20
moon appears	20
national academy	20
sinus iridum	20
many hundred	20
four moons	20
somewhat smaller	20
revolved round	20
sharply defined	20
daily motion	20
must depend	20
annual revolution	20
astronomers royal	20
comparatively low	20
perfect sphere	20
four inches	20
yet known	20
british museum	20
great star	20
equal distances	20
eminent astronomers	20
first thought	20
general laws	20
turning round	20
forty degrees	20
inquire whether	20
high sun	20
white polar	20
white house	20
early times	20
early evening	20
nearly uniform	20
spectroscope shows	20
twenty thousand	20
magnitude companion	20
little later	20
incandescent gas	20
professor airy	20
giant stars	20
johnstone stoney	20
ten seconds	20
circular path	20
now well	20
little book	20
things seen	20
planets around	20
may come	20
earth turns	20
well understood	20
high water	20
whole year	20
like many	20
monthly notices	20
first comet	20
living beings	20
first observation	20
stars seem	20
smaller ring	20
space beyond	20
recent discoveries	20
la place	20
situated near	20
american museum	20
will gradually	20
every step	20
von zach	20
life may	20
telescope tube	20
stones fell	20
max wolf	20
far advanced	20
face towards	20
one month	20
central point	20
bodies revolving	20
chapter xv	20
two degrees	20
following extract	20
comet may	20
good many	20
fine ring	20
light streaks	20
every two	20
present purpose	20
five million	20
somewhat like	20
early years	20
already shown	20
professor hale	20
ancient nations	20
printed papers	20
full daylight	20
thirty degrees	20
largest telescopes	20
curved line	20
convex lens	20
single stars	20
neap tides	20
two astronomers	20
first great	20
globular star	20
constellation hercules	20
various members	20
volcanic eruptions	20
sixteen feet	20
certain number	20
different directions	20
will tell	20
greatest brilliancy	20
professor holden	20
put forth	20
may remark	19
square root	19
practical purposes	19
two seconds	19
may mention	19
luminous vapor	19
free hydrogen	19
sidereal period	19
inner surface	19
electric current	19
light will	19
dark regions	19
meteoric dust	19
first class	19
vacuum tube	19
circular form	19
octagon room	19
half inches	19
great value	19
high powers	19
time required	19
great square	19
fall back	19
due east	19
great mountain	19
various directions	19
eleventh magnitude	19
well founded	19
known fact	19
star catalogue	19
great velocity	19
three centuries	19
also made	19
sidereal day	19
half way	19
will say	19
edward everett	19
nearly overhead	19
first observed	19
distant object	19
makes one	19
red rays	19
prime vertical	19
great height	19
nine times	19
pass away	19
crab nebula	19
two forces	19
sir henry	19
synodical period	19
nearly thirty	19
nova cygni	19
long afterwards	19
one step	19
much correspondence	19
observed phenomena	19
spectroscopic binary	19
mira ceti	19
terrestrial gravity	19
diurnal movement	19
exact position	19
whole extent	19
years hence	19
uniform motion	19
near one	19
third star	19
now become	19
eight inches	19
hours minutes	19
different degrees	19
northern latitudes	19
necessary consequence	19
angular velocity	19
dark interior	19
accurately known	19
harton colliery	19
technical language	19
september th	19
directly overhead	19
will recollect	19
quite clear	19
thousand million	19
french academy	19
star names	19
matter may	19
something else	19
gives rise	19
various stages	19
arctic regions	19
geological survey	19
system may	19
inch hooker	19
iron ships	19
entire heavens	19
gaseous state	19
ever saw	19
iron meteorites	19
six stars	19
pacific ocean	19
separate stars	19
mont blanc	19
easily understood	19
per annum	19
already made	19
vassar college	19
circular orbit	19
lunar observations	19
another class	19
late mr	19
arthur biddell	19
sandford fleming	19
strangely enough	19
solid state	19
new instrument	19
highest point	19
nearly six	19
whole subject	19
main features	19
steady atmosphere	19
one mile	19
author says	19
next step	19
american association	19
comparative sizes	19
vice versa	19
often seen	19
exact time	19
shall presently	19
apparent path	19
eruptive prominences	19
many ways	19
sidereal sphere	19
professor smyth	19
two ways	19
lunar disc	19
mountain ring	19
among others	19
refracting telescopes	19
heavy bodies	19
giant planet	19
part ii	19
far larger	19
moon around	19
may serve	19
thirteen years	18
fifty minutes	18
considerably greater	18
circle described	18
generally speaking	18
seven thousand	18
ball says	18
never saw	18
degrees north	18
stars move	18
surface temperature	18
present knowledge	18
carefully studied	18
professor hall	18
look back	18
second time	18
precisely similar	18
small bright	18
mountain mass	18
every minute	18
almost say	18
moon system	18
path around	18
might suppose	18
entire surface	18
will readily	18
inner planets	18
previous chapter	18
former case	18
parallactic ellipse	18
short periods	18
ten feet	18
large planets	18
creative power	18
light takes	18
vast distance	18
conic sections	18
among many	18
roughly speaking	18
small central	18
ever lived	18
horizontal line	18
one twenty	18
cometary orbits	18
british astronomical	18
great attention	18
electrical currents	18
telescope shows	18
known laws	18
another form	18
drawn towards	18
different bodies	18
must suppose	18
general idea	18
many observers	18
satisfactory explanation	18
old times	18
new jersey	18
inch aperture	18
lunar acceleration	18
south africa	18
carries us	18
perhaps one	18
one whose	18
present work	18
solid particles	18
star must	18
faint light	18
italian astronomer	18
spectroscopic method	18
living matter	18
surface will	18
atlantic ocean	18
ruiz del	18
solar observatory	18
inner one	18
first case	18
soon afterwards	18
star beta	18
general level	18
various distances	18
found convenient	18
nine hours	18
every thirty	18
different ways	18
just visible	18
optical illusion	18
stellar evolution	18
within one	18
two separate	18
chemical composition	18
great law	18
rare occasions	18
must know	18
eastern limb	18
especially interesting	18
general surface	18
summer months	18
generally supposed	18
highest mountains	18
cubic foot	18
hopkins university	18
moves around	18
two comets	18
moving round	18
little craters	18
outer half	18
total mass	18
even among	18
must come	18
earliest ages	18
moves round	18
times larger	18
apparent change	18
however much	18
actual measurement	18
narrow limits	18
universal law	18
report brit	18
point overhead	18
globular cluster	18
two successive	18
teaches us	18
constellation lyra	18
faintest stars	18
opposite points	18
considerable size	18
horizontal parallax	18
apparent place	18
theoretical astronomy	18
unstable equilibrium	18
every variety	18
resolution offered	18
first noticed	18
will begin	18
goes round	18
differential equations	18
much work	18
like one	18
see page	18
terrestrial life	18
every new	18
late dr	18
del arbol	18
just one	18
elliptic orbits	18
moon passes	18
became known	18
whose orbit	18
early life	18
singular fact	18
primum mobile	18
tons per	18
bright spot	18
true system	18
de struve	18
human nature	18
nine hundred	18
just beyond	18
little bodies	18
accurately determined	18
instrumental means	18
called seas	18
central condensation	18
ten degrees	18
maria mitchell	18
great rapidity	17
easily see	17
northern part	17
extreme tenuity	17
general form	17
celestial photography	17
feet thick	17
observer must	17
motion will	17
table ii	17
elliptical orbit	17
going round	17
among men	17
flat ring	17
became visible	17
hard work	17
third edition	17
different rates	17
different seasons	17
outer planet	17
holds good	17
mars will	17
one kind	17
may expect	17
may yet	17
may regard	17
natural science	17
apparent displacement	17
much shorter	17
became evident	17
newtonian law	17
degrees apart	17
sufficient accuracy	17
already pointed	17
never heard	17
known facts	17
dark room	17
small planet	17
might make	17
comet must	17
greatest interest	17
differential calculus	17
nearly five	17
diametrically opposite	17
senior wrangler	17
directed toward	17
disturbing influence	17
great pleasure	17
come together	17
obedient servant	17
unassisted eye	17
still larger	17
reflective power	17
chief star	17
eastern side	17
travel round	17
magnetic disturbances	17
south poles	17
biddell airy	17
hundred stars	17
may note	17
crescent moon	17
carried away	17
james south	17
near us	17
every body	17
place within	17
one among	17
pole will	17
minute craters	17
large meteor	17
lost sight	17
david brewster	17
laden atmosphere	17
large planet	17
twelve miles	17
greater portion	17
polar distance	17
infinite variety	17
looked like	17
comparatively short	17
enormous mass	17
immense distance	17
beautiful object	17
enormous size	17
whole time	17
harvard university	17
remarkable manner	17
human beings	17
directly opposite	17
one hemisphere	17
small angle	17
strongly marked	17
single exception	17
life exists	17
solar phenomena	17
new discoveries	17
seventy miles	17
form one	17
lady huggins	17
equatorial belt	17
luminous bodies	17
large irregular	17
observation made	17
electric currents	17
low density	17
gave us	17
better known	17
moon moves	17
miles thick	17
lady herschel	17
will seem	17
common zero	17
upper regions	17
second edition	17
small mirror	17
whole series	17
perihelion distance	17
simple one	17
almost infinite	17
solar translation	17
last half	17
way round	17
time will	17
nineteen miles	17
solar temperature	17
one minute	17
ordinary telescopes	17
actual size	17
difficult problem	17
scientific investigation	17
just south	17
astronomical tables	17
harvard annals	17
shall take	17
great weight	17
moral law	17
informs us	17
distinct vision	17
new era	17
may arise	17
left us	17
certain point	17
discovery made	17
whose distance	17
less time	17
higher powers	17
solar constitution	17
solar motion	17
circling round	17
circle will	17
favorable conditions	17
favourable circumstances	17
several stars	17
terrestrial volcanoes	17
actual observation	17
seems likely	17
may occur	17
must admit	17
times brighter	17
crowded together	17
seasonal changes	17
greater degree	17
comet will	17
last years	17
first appearance	17
greatest number	17
absolutely necessary	17
great oceans	17
must first	17
may consider	17
great masses	17
meteoritic hypothesis	17
early history	17
computing room	17
diurnal circle	17
interior surface	17
accurate knowledge	17
emperor rudolph	17
various places	17
solar day	17
seems almost	17
ancient astronomers	17
triple star	17
extremely minute	17
smaller bodies	17
charles ii	17
vast numbers	17
true theory	17
mountain arm	17
easily found	17
future time	17
every astronomer	16
mean longitude	16
distant suns	16
direction towards	16
apparent time	16
will doubtless	16
initial point	16
stars scattered	16
assure us	16
many observations	16
called attention	16
approaching us	16
cambridge philosophical	16
considerable time	16
force acting	16
give way	16
bound together	16
us first	16
thirty thousand	16
planet may	16
either case	16
new one	16
magnetic force	16
minute particles	16
bright rays	16
eight hours	16
true position	16
et de	16
one period	16
little group	16
great force	16
mutual relations	16
must follow	16
first instance	16
actually seen	16
metallic lines	16
high light	16
travels round	16
whole visible	16
common motion	16
eight feet	16
will suffice	16
years earlier	16
nine miles	16
geological time	16
purely scientific	16
surrounding space	16
original position	16
let fall	16
now called	16
point near	16
little beyond	16
still smaller	16
meteoric astronomy	16
various sizes	16
first glance	16
south latitude	16
vast amount	16
chapter xiv	16
general public	16
north side	16
early age	16
plumian professor	16
ordinary star	16
take care	16
time occupied	16
urban viii	16
great advance	16
tobias mayer	16
may ask	16
telescopic observations	16
known planets	16
present volume	16
january th	16
several miles	16
looking back	16
distance equal	16
greenwich meridian	16
shooting star	16
post office	16
first saw	16
totally eclipsed	16
century later	16
first letter	16
interesting fact	16
general way	16
every respect	16
mere point	16
last three	16
many small	16
planetary perturbation	16
metric system	16
fifty million	16
time taken	16
tidal wave	16
vast distances	16
inner satellite	16
distant planet	16
teach us	16
twelve days	16
contained within	16
two poles	16
present rate	16
professor schumacher	16
without doubt	16
stars like	16
shall now	16
often happens	16
nebulous stars	16
bodies may	16
winged horse	16
vast mass	16
light travels	16
density must	16
vacant space	16
somewhat greater	16
near keswick	16
little farther	16
makes us	16
good work	16
le monnier	16
alpha herculis	16
average number	16
two cases	16
general principles	16
another point	16
must needs	16
natural phenomena	16
five seconds	16
gaseous condition	16
called canals	16
many days	16
much trouble	16
three quarters	16
several parts	16
level surface	16
first part	16
inhabited worlds	16
plainly visible	16
continually changing	16
tidal action	16
due course	16
little distance	16
celestial globe	16
long exposure	16
remarkable feature	16
binary star	16
terraced walls	16
move around	16
attenuated vapors	16
large body	16
two weeks	16
star marked	16
black spots	16
former times	16
subsequent years	16
outer regions	16