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Scientific Intelligence. — Geology. 
12. General Remarks on the Temperatures of the Terrestrial 
Globe , and of the Planetary Spaces ; by M. le Baron Fourier . — 
M. Fourier’s interesting memoir on the temperature of the globe, 
presents a review of all his inquiries on the subject, and is to be 
considered as exhibiting the present state of our knowledge regard- 
ing a matter of much interest to the geologist, as well as to the na- 
tural philosopher. It may even be said that the question of the 
proper temperature of the globe and of the changes which it may 
have undergone at the surface, forms one of the most important 
bases of geological knowledge. Under this point of view, we are 
happy in being at last able to support, by learned mathematical 
theories, which are only the expression of observed facts, the 
opinions which we have long held out on the subject of the de- 
pression which the temperature of the surface of the earth has 
experienced, — a change to which we have attributed the modifi- 
cations which life has undergone at this surface, by proclaiming 
the return to the principal geological opinions of Buffon as ine- 
vitable. The heat of the earth, according to the learned acade- 
mician, is derived from three sources : 1st, The earth is heated 
by the solar rays, the unequal distribution of which produces 
the diversity of climates ; 2d/y, It participates of the common 
temperature of the planetary spaces, being exposed to the irradi- 
ation of the innumerable stars which surround on all sides the 
solar system ; 3dly, The earth has preserved in the interior of 
its mass a part of the original heat which it contained when the 
planets were formed. M. Fourier then examines separately each 
of these three causes, and the phenomena which it produces. 
We shall only relate here the considerations which are most im- 
portant with regard to geology. The opinion of an internal fire, 
says M. Fourier, the perpetual cause of several great phenomena, 
has been renewed in all the ages of philosophy. The form of 
the terrestrial spheroid, the regular disposition of the internal 
strata rendered manifest by the experiments of the pendulum, 
their density increasing with the depth, and various other consi- 
derations, concur to prove that a very intense heat has formerly 
penetrated all parts of the globe. This heat is dissipated by the 
irradiation into the surrounding space, the temperature of which 
is much inferior to that of freezing water. Now, the mathema- 
tical expression of the law of refrigeration shews, that the origi- 
