176 Geological Results of the Earth's Contraction. 
Arr. XX.— Geological Results of the Earth’s sarah in 
consequence of Cooling ; by James D. Dan 
Tuere are few geological writers at the present day who do 
not admit the former igneous fluidity of our globe.* In this be- 
lief they recognize the fact that the earth has undergone contrac- 
tion as a consequence of cooling, and acknowledge a —— to 
receive as geological truth, whatever may be show the 
natural effects of such contraction. Yet why, after etteibiting to 
this cause, in a general way, much of the unevenness of the 
earth’s surface, should the subject then be dropped, as if no such 
cause had operat — H “ is a of the highest importance 
that an agency so universal and so fundamental in its n nature, 
should be followed ne in all its bearings to the very limits of its. 
possible effects. 
* As matter  Alirena D and on i principle also of “ honor to whom honor,” we 
cite here the following passages rom the Protogea of Leibnitz, written in 1691, 
giving his views respecting the nt in of the saltness of the sea, and the formation 
of ‘mountains and of rock strata.t On the first point he offers the true explanation ; 
and although his viele on the other points require <~ modification, at th exhibit 
the wonderful depth and penetration of his mind. Alludi ing in the outset to an 
original mate of igneous Huidity, he says (§ iv) :— 
“Ex genest rerum jam observata hactenus procedet salsi maris ori 
- perasta, i ay iguere, hamorem attrahunt, unde olea per Jeliguion Chemie 
ascuntur a; ita pronum erit credere, sub rerum initiis, nondum separato a 
lone opaco, cum globus noster adhuc : arderet, pulsu ae ane humorem avian in 
aur ras, deinde num 
vapores iterum v Yhinte densatum, et cima congelascente terest ris Ay erficiei m adi 
resorberetur, in aquam denique. rediisse, que terre er ablu 8 recentis 
em umatis vestigia, salem xum In: se rec de sat um est lixivit 
genus, quod deinde in mare _confluxit.”—* Postrem “credibile ef coderehehiogs 
se refrigeratione crustam, ut in metallis, et aliis, que fusione Pp bulla 
- * . . si 
reliquisse, ingentes pro rei magnitudiue, id est, sub vastis fornicibus us cavitates, qui- 
bus inclusus fuit aér r hamo titer tum etiam in folia quae dam discessisse, et varietate 
materi ealorisqite inagualiter subs ae massas, quin meen e pd frag- 
us eclivia 
andum 
matetiz, be crue apitite, fracti Prise maxi meque, ho mniore cavitanioue per 
ruinas cim deinde 
i ; 
0, 
rurstie sodimenta alla 
hi peteuiia nies 
simili causa, strata palecet diver alia aliis imponerentur, repo teneri adbuc orbis 
sepius novata est. Donec quiescent “se causis atque equilibratis, consistentior 
emergeret status rerum. Ur ide jam duplex origo intelligitur firmorum corporum ; 
una, ciim ab ignis fusione relriyeenseheiat altera cm concrescerent ex solu tione 
aquarum. eae igitur putandum est /apides ex sola esse Id enim potis- 
simum de prima tantim massa ac terre basi accipio ; si © dubito, postea materiam 
liquidam in superficie rage ite ves: quiete reddita, ex ramentis 
subactis ingentem materi# vim deposvisse, quorum stir dens con species form- 
arunt, alia in saxa induruere, : ts strata diversa ke fener imposita diversas 
ee vices bique intervalla testantur.” Here we have in general terms 
just mean betwee : n Wernerism and Huttonism attaitield long before either 
_ Again, | e remarks as follows, after some explanations, on the eleyation of moune 
tains, § xxii :—“ "Eso ut facilé admittam, initio cim liquida esset massa globi terre, 
¥ An abstract of this pa issage is given by Lyell in his Principles of Geol nd with illustrative 
remarks by Cony Deere in the Rep. Brit. Assoc., 1832, "368 ; also a brief abstract of the Proto- 
gwa by Prof. E. Mitchell, may be ound in this Journal, xx, 56, 1831. 
