60 Temperature of the Terrestrial Globe, 
heat, the temperature, at this time, is more than 2000 degrees, (3) 
at a distance from.the surface not exceeding the one hundredth 
of the earth’s radius; while at the centre of our globe this tem- 
perature surpasses 200,000 degrees, estimating it according to the 
ordinary formulas which relate to solid, homogeneous bodies. (4) 
But, although this explanation has been generally adopted, I have 
shown, in my work, the difficulties which it presents, and which, 
it appears to me, render it inadmissible. I believe I have there 
shown in what manner the earth must have long since lost all 
heat which it may primitively have had; and subsequent reflec- 
tion having confirmed me in this opinion, I shall present it here 
with more precision and assurance than at first. 
The almost spherical form of the earth and planets, and their 
depression at the poles of rotation, leave no room to doubt that 
these bodies were originally in a fluid state. In the problem 
having for its object the determination of the figure of these 
bodies, geometricians consider them, in fact, as liquid masses, 
composed of layers, each having the same density throughout all 
its extent ; and the whole revolving round the same axis, of con- 
stant direction, with a known and constant velocity. The den- 
sity decreases, from one layer to another, in receding from the 
centre towards the surface, either because these heterogeneous 
layers have distinct densities, and are regarded as incompres- 
sible, and that the most dense have sunk towards the centre 
for the stability of the system; or rather because, according to 
the opinion of D. Bernouilli, subsequently revived by Thomas 
Young, all these layers were formed of one homogeneous liquid, 
susceptible of a certain degree of compression, and of which the 
density consequently increases, in approaching the centre, by 
reason of the pressure, also increasing, which the liquid exercises 
upon itself. In either case they suppose the entire mass of liquid, 
(3) Centigrade division is that employed by the author, throughout his work. 
(4) At page = of the author’s Théorie Mathématique de la Chaleur, he has the 
saa pass 
* At the pace and throughout the greater part of its mass, the materials of 
which the earth is composed would then be in a state of incandescent gas; yet 80 
condensed that their mean density would surpass, five times, that of water. To 
contain these, at such a degree of condensation and of heat, an extraordinary force 
would be necessary, of which we can form little idea; and we may doubt hres the 
layers of the globe would have thickness and cohesion sufficient to 
= fluid layers.” 
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