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Show 2tl CONSTI'rUENT MATERIA L S OF THE EARTH, equal in height to nearly t h e h'J g best onfd o suhra Arpn doefs .o uTtlihneey, are generally of extre:n:e steepfe~s, da for in a planet defia peculiartly which migh\be. oo {e'ng that these are the cient in water and atmosp 1er ed seei on the surface of our agents which wear down r~gge nesson a stupendous scale. Th 1 ic operatwns are h'l earth. e vo can .. o·ht s ots of t:he moon, w I e They are the cau~e oft~~ .b~!:::>guishes the duller portions, the want of them IS w la IS In In some parts, bright usually but erronP-ously calle~ seas. lar e atch radiates volcanic matter, besides .covering onetud!el with' subordiout in long streams, W~ICh fappe~r ~ · Other objects of a nate .foci of the same lund o .eneigy. mountains mounts most ''r emarka ble c h ar.a ctef r a·rteh lyn nvgo-lcanoes, sur' rounded like th.ose of the craters o .~;~und circular pits, hollowed immediately by vast a~d pr th e again being surrounded under the genel·al sur ace, . es rising far above the cen-by a circular :vall o~ m.~untfin,hich are terraces about the tral one, and 1n the II~SI e 0 w. e The well-known same height. as the Inner efn~:~t~r· called by astronobright spot In the s~~t~-eas b~ readi'ly distinguished b.Y mers, 1'ycho, al!-d w lC can rin -mountains. There IS the naked ey~, I~ on~ of th~s~ithg a it 22,000 feet deep; one ~f 200 .miles In rl~amete Etna. I~ is remark~bl~, th~t that Is, twic~ the hei~lt o~oldt of a volcanic distnct I:Q the maps g~ven bJ u~llustrative of the formerly valSouth America, an one I . France present features sctarnikicin gdilsyt rh~kcte omfa nAuyv pearr. fsn eo, /~he moon:s surface, as seen through a good gla~s.. th~ moon forbjd the idea that These charactenshcs lof t. f life like the earth, and it can be at presel1t .a ~~~~I~ ~~ever can become so. But almost seem to dec are such conclusions. The we must not rashlr dravv· a.\tfer stage of the progress moon may be only In an ear . one The elenlents through which th~ earth ha~:l~~~~~! co~binations diffewhich seem wanh.ng m~y -re and may yet be deverent in those whiCh ~xlst ~€ as' may yet fill the profound lop8d as \Ve here find t Cln. ~ here may spread over hollows of the surface.; an a ts~~rFe place, meteorologic.al the whole. Should these ev~n na of organic life will lJhenornena, and all the p l ~:o~~e earth will become a commence, and ~he moon, 1 e ' green and inhabttcd world. proof in "avor of any It is unavoidably held as a strong . AN'D OF TltE OTHElt BODIES OF SP AC.Jt:. 2fi nypothesis, when all the relative phenomena are in har mony with it. This is eminently the case with the nebulous hypothesis, for here the associated facts t\annot be explained on any other supposition. We have seen reason to conclude that the prithary condition of matter was that of a diffused mass, in which the component molecules were probably kept apart through the efficacy of heat: that portions of this agglomerated into suns, which threw off planets ; that these planets were at first very mu~th diffused, out gradually contracted by cooling to their present dimensions. Now as to our own globe, there is a remarkable proof of its having been in a fluid state at the time when it was finally solidifying, in the fact of its be .. ing bulged at the equator, the very form which a soft revolving body takes, and must inevitably take, under tha influence of centrifugal force. This bulging makes the equatorial exceed the polar diameter as 230 to 229, which has been demonstrated to be precisely the departure from a correct sphere which might be predicted from a knowledge of the amount of the mass and the rate of rotation. There is an almost equally distinct memorial of the original high temperature of the materials, in the store of heat which still exists in the interior. The immediate surface of the earth, be it observed, exhibits only the temperature which might be expected to be imparted to such materials, by the heat of the sun. There is a point very short way do\'\rn, hut varying in different climes, where all effects from the sun~s rays ceases. Then, however, commences a temperature from an entirely different cause, one which evidently has its source in the interior- of the earth, and ·which regularly increases as we descend to greater and gteater depths, the rate of increment being about one degree Fahrenheit for every sixty feet; a:.td of this high temperature there are other evidences in the phenomena of volcanoes and thermal springs, as well as in what is ascertained with regard to the density of the entire mass of the earth. This, it will be remembered, is four and a half times the weight of water; but the actual weight of the principal solid substances composing the outer crust is as two and a half times the weight of water ; and this, we know, if the globe were solid and cold, should increase vastly towards th.e centre, water acquiring the density of quir.ksilver at 362 miles below the surface, and other things 111 proportion, and these densities becoming much 3 |