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The country, by reason of its vast caverns and sub How tae lit lake shines, a phosphoric sea, terraneous fires, has been miserably torn by earth And the big rain comes dancing to the earth! quakes, so that the whole face of it is quite changed. And now again 'ris black,, and now,
the glee Addison on Italy. Of the loud hills shakes with its mountain-mirth, The god for ever great, for ever king,
As if they did rejoice o'er the young earthquake's Who slew the earthborn race and measures right
Id. To heaven's great habitants !
Earth, in ancient philosophy. See CHEMISTo earthlinys, the footstool of God, that stage which
TRY and ELEMENT. be raised for a small time, seemeth magnificent.
The Earth, in astronomy, is one of the primary
planets. See ASTRONOMY. • Although the rela
tive densities of the earth and most of the other Two earths, at the least, ere ye sow it bestow. Tusser.
The five genera of earths are, 1. Boles. 2. Clays. planets have been known a considerable time, it 3. Marls. 4. Ochres. 5. Tripelas.
is but very lately that we have come to the
Hill's Mat. Medica. knowledge of the absolute gravity or density of Of English talc, the coarser sort is called plaister or the whole mass of the earth. This, says Dr. parget; the finer, earthflax, or salamander's hair. Hutton, I have calculated and deduced from the
Woodward. observations of Dr. Maskelyne, astronomer royal, As a rustick was digging the ground by Padua, he at the mountain Schehallien in the years 1774, 5, found an urn, or earthen pot, in which there was and 6. The attraction of that mountain on a another urn, and in this lesser a lamp clearly burning. plummet, being observed on both sides of it, and
its mass being computed from a number of secLamps are infamed by the admission of new air, when the sepulchres are opened, as we see in fai tions in all directions, and consisting of stone; these earthy vapours of divers sorts. Id. Math. Mag.
data being then compared with the known attracIt must be our solemn business and endeavour, at
tion and magnitude of the earth, gave by proporfit seasons, to turn the stream of our thoughts from tion its mean density; which is to that of water earthly towards divine objects.
as nine to two, and to common stone as nine to The plow reckoned the most proper for stiff black five; from which very considerable mean density,
it clays, is one that is long, large, and broad, with a
may be presumed, that the internal parts condeep head and a square earthboard, so as to turn up a
tain great quantities of metals. From the dengreat surrow.
Mortimer. sity now found,' adds this writer, ' its quantity of Hence foxes earthed, and wolves abhorred the day, matter becomes known, being equal to the proAnd hungry churls ensnared the nightly prey. duct of its density by its magnitude.'
Tickel. Mr. Boyle suspected that there are great, Sudden he viewed, in spite of all her art, though slow, internal changes, in the mass of the An earthly lover lurking at her heart. Pope. earth. He argues from the varieties observed in
Now scarce withdrawn the fierce earthshaking power, the change of the magnetic needle, and from the Jove's daughter Pallas watched the fav’ring hour;
observed changes in the temperature of climates. Back to their caves she bade the winds to fly,
But as to the latter, there is reason to doubt that And hushed the blustering brethren of the sky. Id. Poor, earth-created man! Young,
he could not have diaries of the weather sufficient a thousand furies more did shake
to direct his judgment. Boyle's Works, Abr. Those weary realms, and kept earth-loving man awake.
Vol. I, p. 292, &c.
Armstrong. Respecting the figure of the earth, the ancients It is no uncommon thing for the honour of an had various opinions : some, as Anaximander earthly monarch to be wounded through the sides of and Leucippus, held it cylindrical, or in the his ministers.
Hason. form of a drum : but the most general opinion The only amaranthine flower on earth
was, that it was flat; that the visible horizon was Is virtue; the only lasting treasure, truth. the boundary of the earth, and the ocean the
boundary of the horizon: that the heavens and Behold your bishop! well he plays his part, earth above this ocean were the whole visible Christian in name, and infidel in heart;
universe: and that all beneath the ocean was Ghostly in office, earthly in his plan, A slave at court, elsewhere a lady's man. I.
Hades. Of this opinion were some of the ChrisMan mounts on man, on camels camels rush,
tian fathers, as Lactantius, St. Augustine, &c. Hosts march o'er hosts, and nations nations crush,
Such of the ancients, however, as understood any Wheeling in air the winged islands fall,
thing of astronomy, and especially the doctrine of And one great earthy ocean covers all! Darwin. eclipses, must have been acquainted with the cir
Earthquakes have raised to heaven the humble vale, cular figure of the earth; as the ancient BabyloAnd gults the mountain's mighty mass entombed ; nian astronomers, who had calculated eclipses And where the’ Atlantic rolls wide continents have long before the time of Alexander, and Thales bloomned,
Beattie. the Grecian, who predicted an eclipse of the sun. Earth's coarsest bread, the garden's bomeliest It is now indeed agreed on all hands, that the form roots,
of the terraqueous globe is globular or very nearly And scarce the summer luxury of fruits,
so. See Astronomy. This is equally evident His short repast in humbleness supply
from the eclipses of the sun and of the moon; With all a hermit's board would scarce deny. Byron.
in all of which the earth's shadow appears circu
Impart The purity of heaven to earthly joys,
lar upon the face of those bodies, what way Expel the venom and not blunt the dart soever it be projected, whether east, west, north, The dull satiety which all destroys
or south; and howsoever its diameter vary, And root from out the soul the deadly weed which according to the greater or less distance from the cloys.
Id. earth. The spherical figure of the earth is also
evinced from the rising and setting of the sun, vestigate the cause of this phenomenon; which moon, and stars; all which happen sooner to they attributed to the revolution of the earth those who live to the east and later to those liv- about its axis. If the earth were in a fluid ing to the west, and that more or less so, according state, its rotation round its axis would necessarily to the distance. So also, going or sailing to the make it put on such a figure, because, the centrinorth, the north-pole and northern stars become fugal force being greatest towards the equator, more elevated, and the south-pole and southern the Auid would there rise and swell most; and, stars more depressed; the elevation northerly that its figure really should be so now, seems neincreasing equally with the depression southerly'; cessary, to keep the sea in the equinoctial regions and either of them proportionably to the distance from overflowing the earth about those parts. gone. The same thing happens in going to the See this curious subject well treated by Huygens, south. Besides, the oblique ascensions, descen- in his discourse De Causâ Gravitatis, p. 154, sions, emersions, and amplitudes of the rising where he states the ratio of the polar diameter to and setting of the sun and stars, in every latitude, that of the equator, as 577 to 578. And Neware agreeable to the earth's spherical form: all ton, in his Principia, first published in 1686, which could not happen if it were of any other demonstrates from the theory of gravity, that the figure. The globular form of the earth is farther figure of the earth must be that of an oblate confirmed by its having been often sailed round: spheroid, generated by the rotation of an ellipse the first of these important voyages was made in about its shortest diameter, provided all the parts 1519, by Ferdinand Magellan, who accomplished of the earth were of a uniform density throughit in 1124 days. In 1557 Sir Francis Drake out; and that the proportion of the polar to the performed the same voyage in 1056 days: in equatorial diameter of the earth, would be that 1586 Sir Thomas Cavendish performed it in 777 of 689 to 692, or nearly that of 229, to 230, or days; Simon Cordes, of Rotterdam, in 1590, in as :9956522 to 1. This proportion of the two 1575 days: in 1598 Oliver Noort, a Hollander, diameters was calculated by Newton in the folin 1077 days; Van Schouten, in 1615, iu 749 lowing manner: having found that the centrifudays; Jacob Heremites and John Huygens, in gal force at the equator is my of gravity, he as1623, in 802 days. Many others have since per- sumes, as an hypothesis, that the earth is to the formed it, particularly Anson, Bougainville, and diameter of the equator as 100 to 101, and Cook; sometimes sailing round by the east some- thence determines what must be the centrifugal times by the west, till at length they arrived again force at the equator to give the earth such a in Europe, whence they set out; and, in the form, and finds it to be sts of gravity : then, course of their voyage, observed that all the phe- by proportion, if a centrifugal force equal to t nomena, both of the heavens and the earth, cor- of gravity would make the earth higher at the respond to, and prove this spherical figure. equator than at the poles by ra of the whole
The natural cause of this form of the globe is, height at the poles, a centrifugal force that is according to Sir Isaac Newton, the great princi- of gravity will make it higher by a proportional ple of attraction, with which the Creator has excess, which by calculation is als of the height endued all the matter in the universe; and by at the poles; and thus he discovered, that the which all bodies, and all the parts of bodies, diameter at the equator is to the diameter at the mutually attract one another. This is also the poles, or the axis, as 230 to 229. But this comcause of the sphericity of the drops of rain, putation supposes the earth to be every where quicksilver, &c. The inequality of the surface of of a uniform density ; whereas if the earth is the earth, by mountains and valleys, is nothing more dense near the centre, then bodies at the considerable; the highest eminence being scarcely poles will be more attracted by this additional equivalent in its proportion to the bulk of matter being nearer; and therefore the excess of the earth to the minutest protuberance on the the semi-diameter of the equator above the surface of an orange. Its difference from a semi-axis, will be different. According to this perfect sphere, however, is more considerable proportion between the two diameters, Newton in another respect, by which it approaches farther computes, from the different measures of nearly to the shape of an oblate spheroid; a degree, that the equatorial diameter will exceed being a little flatted at the poles, and raised the polar by thirty-four miles and g. Nevertheabout the equatorial parts, so that the axis from less, Messrs. Cassini, both father and son, the pole to pole is less than the equatorial diameter. one in 1701, and the other in 1713, attempted to What gave the first occasion to the discovery of prove, in the Memoirs of the Royal Academy of this important circumstance was, the observa- Sciences, that the earth was an oblong spberoid: tions of some French and English philosophers and in 1718, M. Cassini again undertook, from in the East Indies, and other parts, who found observations, to show that, on the contrary, the that pendulums, the nearer they came to the longest diameter passes through the poles; which equator, performed their vibrations slower: gave occasion for Mr. John Bernouilli
, in his whence it follows, that the velocity of the descent Essai d'une Nouvelle Physique Celeste, printe} of bodies, by gravity, is less in countries nearer at Paris in 1735, to triumph over the British por to the equator; and consequently that those parts losopher, apprehending that these observations are farther removed from the centre of the earth, would invalidate what Newton had demonstrated. or from the common centre of gravity. See the And in 1720 M. De Mairan advanced arguHistory of the Royal Academy of Sciences, by ments, supposed to be strengthened by geometDu Hamel, p. 110, 156, 206; and L'Ilistoire de rical demonstrations, farther to confirm the 2l'Academie Roy. 1700 and 1701. These obser- sertions of Cassioi. But in 1735 two companies ations having established the fact also stimu- of mathematicians were employed, one for a lated M. Huygens and Sir Isaac Newton to in- northern, and another for a southern expediuos,
the result of whose observations and measure- earth's figure, and for the ellipticity of the homoment plainly proved that the earth was flatted at geneous spheroid,
P- II the poles. The proportion of the equatorial
= 2€-o: therefore 8 = 28diameter to the polar, as stated by the gentlemen Il
n employed on the northern expedition for mea- and, therefore, according to your observation, suring a degree of the meridian, is as 1 to 0.9891 ; =. This is the just conclusion from your by the Spanish mathematicians as 266 to 265, or observations of the pendulum, taking it for as 1 to 0-99624 : by M. Bouguer as 179 to 178, granted that the meridians are ellipses : which is or as 1 to 0.99441. As to all conclusions, how
an hypothesis upon which all the reasonings ever, deduced from the length of pendulums in of theory have hitherto proceeded. But, plausidifferent places, it is to be observed, that they ble as it may seem, I must say that there is much proceed upon the supposition of the uniform reason from experiment to call it in question. density of the earth, which is a very improbable If it were true, the increment of the force which circumstance; as justly observed by Dr. Horsley actuates the pendulum as we approach the poles, in his letter to captain Phipps: 'you finish your should be as ihe square of the sine of the latitude: article, he concludes, relating to the pendulum or, which is the same thing, the decrement, as with saying, that these observations give a figure we approach the equator, should be as the square of the earth nearer to Sir Isaac Newton's com- of the cosine of the latitude. But whoever takes putation, than any others that have hitherto been the pains to compare together such of the obsermade;' and then you state the several figures vations of the pendulum in different latitudes, as given, as you imagine, by former observations, seem to have been made with the greatest care, and by your own. Now it is very true, that, if will find that the increments and decrements do the meridians be ellipses, or if the figure of the by no means follow these proportions; and, in earth be that of a spheroid generated by the those which I have examined, I find a regularity revolution of an ellipsis, turning on its shorter in the deviation which little resembles the mere axis, the particular figure, or the ellipticity of error of observation. The unavoidable concluthe generating ellipsis, which your observations sion is, that the true figure of the meridians is give, is nearer to what Sir Isaac Newton saith it not elliptical. If the meridians are not ellipses, should be, if the globe were homogeneous, than the difference of the diameters may indeed, or it any that can be derived from former observations. may not, be proportioned to the difference beBut yet it is not what you imagine. Taking the tween the polar and the equatorial force; but gain of the pendulum in latitude 79° 50' exactly it is quite an uncertainty, what relation subas you state it, the difference between the equa- sists between the one quantity and the other; torial and the polar diameter is about as much our whole theory, except so far as it relates to the less than the Newtonian computation makes it, homogeneous spheroid, is built upon false asand the hypothesis of homogeneity would re- sumptions, and there is no saying what figure of quire, as you reckon it, to be greater. The pro- the earth any observations of the pendulum give.' portion of 212 to 211 should indeed, according Dr. Horsley then lays down the following table, to your observations, be the proportion of the which shows the different results of observations force that acts upon the pendulum at the poles to made in different latitudes; in which the first the force acting upon it at the equator. But this is three columns contain the names of the obserby no means the same with the proportion of the vers, the places of observation, and the latitude equatorial diameter to the polar. If the globe were of each ; the fourth column shows the quantity homogeneous the equatorial diameter would ex- of p II in such parts as II is 100,000, as deceed the polar by išo of the length of the latter: duced from comparing the length of the penduand the polar force would also exceed the equa- lum, at each place of observation, with the length torial by the like part. But, if the difference be- of the equatorial pendulum as termed by M. tween the polar and equatorial force be greater than Bouguer, upon the supposition that the increzo (which may be the case in an heterogeneous ments and decrements of force, as the latitude is globe, and seems to be the case in ours), then increased or lowered, observe the proportion the difference of the diameters should, according which theory assigns. Only the second and the to theory, be less than sto, and vice versa, Ï last value of p-11 are concluded from comconfess this is by no means obvious, at first parisons with the pendulum at Greenwich and sight; so far otherwise, that the mistake, which at London, not at the equator. The fifth column you have fallen into, was once very general. shows the value of o corresponding to every value Many of the best mathematicians were misled of p- II, according to Clairault's theorem : by too implicit a reliance upon the authority of Newton, who had certainly confined his inves
Observers. Places. Lat.
8 tigations to the homogeneous spheroid, and had thought about the heterogeneous only in a loose
Bouguer Equator 0 0 and general way. The late Mr. Clairault was the
Bouguer Porto Bello 34 741.8 The first who set the matter right, in his elegant and Green Otaheitee 17
29 563.2 3:26 subtle treatise on the figure of the earth. That
Bouguer San Domingo 18 27 591.0 to work has now been many years in the hands of Abbé de La Il Cape of mathematicians, among whom I imagine there
Caille s Good Hopes are none, who have considered the subject atten
48 50 585:1 31 tively, that do not acquiesce in the author's con TheAcadeclusions. In the second part of that treatise, it
66 48 565.9 kg
micians , is proved, that putting p for the polar force, II Capt. Phipps
79501471•2 ohi for the equatorial, & for the true ellipticity of the
* By this table it appears, that the observations joined, and mo drawn parallel to aC: Co is the
less axis and published by Mr. Robertson, serves to find cos. Ex: ✓ Then
tan. E the proportion between the axis and the equato
greater axis rial diameter, from measures of a degree of the But M, or the length of a degree, obtained by meridian in two different latitudes, supposing the actual mensuration in different latitudes, is known earth an oblate spheroid. Let A Pap (Pl. 124, from the following table:fig. 1.) be an ellipse representing a section of the earth through the axis Pp; the equatorial diameter, or the greater axis of the ellipse, being
Lat. Value of M. Aa; let E and F be two places, where the measure of a degree has been taken ; these measures
Maupertuis, &c. 66° 20° are proportional to the radii nf curvature in the
M = 57438 Cassini and
49 22 M = 57074 ellipse at those places; and if CQ, CR, be con
45 00 M = 57050 jugates to the diameters whose vertices are E
43 00 M = 56972 and F, CQ will be to CR in the subtriplicated
De la Caille
33 18 M = 57037 ratio of the radius of curvature at E to that at
Juan and Ulloa
M = 56768 F, by Cor. 1, Prop. 4, part 6, of Milnes's Conic
Bouguer Sections, and therefore in a given ratio to one
M = 56753 Condamine
M 56749 another; also the angles QCP, RCP, are the latitudes of E and F; so thal, drawing QV rallel to P p, QXY W to Aa, these angles being Now, by comparing the first with each of the given, as well as the ratio of CQ to CR, the following ones; the second with each of the folrectilinear figure CVQXRY is given in species; lowing; and in like manner the third, fourth, and and the ratio of VC? — ZC? (=QXXW) fifth, with each of the following; there will be to RZ-QV?= (RX X XS) is given, which obtained twenty-five results, each showing the is the ratio of CA? to CPtherefore the ratio relation of the axes or diameters; the arithmetiof CA to C P is given. Hence, if the sine and cal means of all of which will give that ratio as cosine of the greater latitude be each augmented 1 to 0.9951989. If the measures of the latitude in the subtriplicate ratio of the measure of the of 49° 22', and of 45° which fall within the degree in the greater latitude to that in the lesser, meridian line drawn through France, and which then the difference of the squares of the aug
have been re-examined and corrected since the mented sine, and the sine of the lesser latitude, northern and southern expedition, be compared will be to the difference of the squares of the co- with those of Maupertuis and his associates in sine of the lesser latitude, and the augmented the north, and that of Bouguer at the equator, cosine, in the duplicate ratio of the equatorial there will result six different values of the ratio to the polar diameter. For Cg being taken in of the two axes: the arithmetical mean of all CQ equal to CR, and qu drawn parallel to QV, which, is that of 1 to 0-9953467, which may be Cv, and vg, CZ and į R will be the sines and considered as the ratio of the greater axis to the cosines of the respective latitudes to the same less: which is as 230 to 228-92974, or 215 to radius; and CV, VQ, will be the augmentations 214, or very near the ratio as assigned by Newof Cv and Co in the ratio named. Hence, to
Now the magnitude, as well as the figure find the ratio between the two axes of the earth, of the earth, that is, the polar and equatorial let E denote the greater, and F the lesser of the diameters, may be deduced from the foregoing two latitudes, M and N the respective measures problem. For, as half the latus rectum of the taken in each; and
greater axis A a is the radius of curvature at A, M
it is given in magnitude from the degree mealet P denote 37
: then Ñ
sured there, and thence the axes themselves are ✓co cos.? F - Px cos.? E less axis
given. Thus, the circular arc whose length is
equal to the radius being 57.29578 degrees, if this Po x sin. "E-sin. ?F
number be multiplied by 56750 toises, the meaIt also appears from the above problem, that sure of a degree at the equator, as Bouguer has when one of the degrees measured is at the equa- stated it, the product will be the radius of cur tor, the cosine of the latitude of the other being vature there, or half the latus rectum of the augmented in the subtriplicate ratio of the de- greater axis; and this is to half the less axis in grees, the tangent of the latitude will be to the the ratio of the less axis to the greater, that is, as tangent answering to the augmented cosine,' in 0.9953467 to 1; whence the two axes are 6583820 the ratio of the greater axis to the less. For, and 6564366 toises, or 7913 and 7950 English supposing E the place out of the equator, then, miles: and the differences between the two ares if the semi-circle Pimnp be described, and IĆ about thirty-seven miles. See Robertson's Navi
gation, vol. ii. p. 206, &c. Suite des Mem, de various theories that have been formed upon this l'Acad. 1718, p. 247, and Maclaurin's Fluxions subject, would, however, not only swell this vol. II. book i. chap. xiv. And very nearly the article beyond our bounds, but be fatiguing to same ratio is deduced from the lengths of pendu- many readers. As far as human industry has lums vibrating in the same time, in different hitherto penetrated, it has been found that the latitudes; provided it be again allowed, that the substances of which the earth is composed are meridians are real ellipses, or the earth a true neither ranged in a regular series, according to spherrid, which, however, can only take place in their specific gravities, nor yet thrown together in the case of a uniform gravity in all parts of the total disorder, as if by accident or chance. But earth. Thus, in the new Petersburgh Acts, for the depth of the earth, from the surface to the 1788 and 1789, are accounts and calculations of centre, is nearly 4000 miles; and yet the deepest experiments relative to this subject, by M. Krafft. mine in Europe, that at Cotteberg, in Hungary, These experiments were made at different times is not more than 1000 yards deep; so that little and in various parts of the Russian empire. This is as yet known of its interior parts. From what gentleman has collected and compared them, and has been discovered, however, of those parts drawn the proper conclusions from them: thus, which lie most contiguous to our observation, he infers, that the length x of a pendulum that naturalists have compared the structure of the swings seconds in any given latitude X, and in a earth to the coats of an onion, or the leaves of a temperature of 10° of Reaumur's thermometer book. And indeed, except in some of those immay be determined by this equation :
mense mountains which have existed from the r = 439.178 + 2-321 sine ?, lines of a French creation, or at least from the deluge, where the foot,
matter, from whatever cause, is more homogeneor x = 39.0045 + 0.206 sine , in English in- ous, the earth is found to consist of various strata ches, in the temperature of 53 of Fahrenheit's or layers, which differ according to the circumthermometer. This expression nearly agrees, not stances of climate and situation. The surface only with all the experiments made on the pen- generally consists of a confused mixture of dedulum in Russia, but also with those of Mr. cayed animal and vegetable substances and earths Graham in England, and those of Mr. Lyons in rudely united together but, upon digging below 79° 50' N. lat., where he found its length to be this surface, the materials of the globe are found 431-38 lines. It also shows the augmentation of arranged in a more regular manner. Heaps of gravity from the equator to the parallel of a given stone are indeed frequently found, which do not latitude 1 : for, putting g for the gravity under consist of layers, but are confused masses of unthe equator, G for that under the pole, and y for equal thickness and are called rocks. The strata that under the latitude , M. Krafft finds are generally extended through a whole country, y=(1 + 0.0052848 sine ?)g; and therefore G and perhaps, with some interruptions and varie= 1:0052848 g. From this proportion of gravity ties, through the globe itself. When the country under different latitudes, the same author infers, is flat, these extensive bodies are found most rethat, in case the earth is a homogeneous ellipsoid, gular, being in that case nearly parallel to the its oblateness must be my instead of sto; horizon, though often dipping downwards in a which ought to be the result of this hypo- certain angle; in many places the beds have a thesis; but on the supposition that the earth is a wave, as where the country consists of gently heterogeneous ellipsoid, he finds its oblateness, waving hills and vales; and here also they in as deduced from these experiments, to be general dip. In passing over the ground the soil $; which agrees with that resulting from the is found, perhaps to the extent of a mile, mostly measurement of some of the degrees of the me- composed of sand; and perhaps for another it ridian. This confirms an observation of M. De consists chiefly of clay: which is occasioned by la Place, that if the hypothesis of the earth's ho- the edges of the different strata lying with an obmogeneity be given up, then the theory, the mea- liquity to the horizon. By a similar projection, surement of degrees of latitude, and experiments mountains, or ridges of mountains, are produced with the pendulum, all agree in their result with which commonly have what is called a back and respect to the oblateness of the earth. See Me- a face, the former smoother, and the latter more moires de l'Acad. 1783, p. 17. In the Philos. rugged. It is generally found, also, that the Trans. for 1791, p. 236, Mr. Dalby has given ascent is more gradual on the one side of a mountain some calculations on measured degrees of the than on the other; and this is occasioned by the meridian, from whence he infers, that those de- strata, which have risen above the general level grees measured in middle latitudes, will answer of the country, being abruptly broken off. The nearly to an ellipsoid whose axes are in the ratio order, number, situation with respect to the assigned by Newton, viz. that of 230 to 229. horizon, depth, intersections, fissures, color, conAnd as to the deviations of some of the others, sistence, &c., of these strata have been consiviz. towards the poles and equator, he thinks dered by Dr. Woodward with great attention. they are caused by the errors in the observed ce- The origin and formation of them all is ascribed
by him to the deluge. He supposes that, at The cosmogony, or knowledge of the original that dreadful revolution, all sorts of terrestrial formation of the earth, the materials of which it bodies had been dissolved and mixed with the was composed, and by what means they were waters, forming altogether, a chaos or confused disposed in the order in which we see them, is a mass; and he also supposes, that this mass of tersubject, which, though perhaps beyond the reach restrial particles, intermixed with water, was at of human sagacity, has exercised the ingenuity length precipitated to the bottom; and that, in of philosophers in all ages. To enter into the general, according to the order of gravity, the