162 JOSEPH FOURIER. 



close of his life lie gave uiiinistakable evidence that he thought it un- 

 justj by causiug his me?iioir to be printed in our volumes without chang- 

 ing a single word. Still, the doubts expressed by the commissioners of 

 the Academy reverted incessantly to his recollection. I^om the very 

 beginning they bad poisoned the pleasure of his triumph; These first 

 impressions, added to a high susceptibility, explain how^ Fourier ended 

 hy regarding with a certain degree of displeasure the efiorts of those 

 geometers who endeavored to improve his theory. This, gentlemen, 

 was a very strange aberration of a mind of so elevated an order. Our 

 colleague had almost forgotten that it is not allotted to any person to 

 conduct a scientific question to a definitive termination, and that the 

 important labors of D'Alembert, Clairaut, Euler, Lagrange, and La- 

 place, while immortalizing their authors, have continually added new 

 luster to the imperishable glory of Newton. Let us act so that this ex- 

 amjde may not be lost. While the civil law imposes upon the tribunes 

 tbe obligation to assign the motives of their judgments, the academies, 

 which are the tribunes of science, cannot have even a pretext to escape 

 from this obligation. Corporate bodies, as well as individuals, act 

 wisely when tliey reckon in every instance only upon the authority of 

 reason. 



At any time the "Theorie Mathematique de la Chaleur" would have 

 excited a lively interest among men of reflection, since, upon the suppo- 

 sition of its being complete, it threw light upon the most minute pro- 

 cesses of the arts. In our own time the numerous points of aifinity ex- 

 isting between it and the curious discoveries of the geologists have 

 made it, if I may use the expression, a work for the occasion. To point 

 out the intimate relation which exists between these two kinds of 

 researches would be to present the most important part of the discov- 

 eries of Fourier, and to show how hapinly our colleague, by one of 

 those inspirations reserved for genius, had chosen the subject of his 

 researches. 



The parts of the earth's crust which the geologists call the sediment- 

 ary formations were not formed all at once. The waters of the ocean, 

 on several former occasions, covered regions which are situated in the 

 present day in the center of the continent. There they deposited, in 

 thin horizontal strata, a series of rocks of different kinds. These rocks, 

 although superposed like the layers of stones of a wall, must not be con- 

 founded together. Their dissimilarities are palpable to the least prac- 

 ticed eye. It is necessary, also, to note this capital fact, that each 

 stratum has a well-defined limit; that no process of transition connects 

 it with the stratum which it supports. The ocean, the original source 

 of all these deposits, underwent then formerly enormous changes in its 

 chemical composition, to which it is no longer subject. 



With some rare exceptions, resulting from local convulsions, the effects 

 of which are otherwise manifest, the order of antiquity of the successive 

 strata of rocks which form the exterior crust of the globe ought to be 



