408 JOSEPH FOURIER. 
MATHEMATICAL THEORY OF HEAT. 
The administrative duties of the prefect of lIsére 
hardly interrupted the labours of the geometer and the 
man of letters. It is from Grenoble that the principal 
writings of Fourier are dated; it was at Grenoble that 
he composed the Théorie Mathématique de la Chaleur, 
which forms his principal title to the gratitude of the 
scientific world. 
I am far from being unconscious of the difficulty of 
analyzing that admirable work, and yet I shall attempt 
to point out the successive steps which he has achieved 
in the advancement of science. You will listen to me, 
Gentlemen, with indulgence, notwithstanding several 
minute details which I shall have to recount, since I 
thereby fulfil the mission with which you have hon- 
oured me. 
The ancients had a taste, let us say rather a passion, 
for the marvellous, which caused them to forget even 
the sacred duties of gratitude. Observe them, for exam- 
ple, grouping together the lofty deeds of a great number 
of heroes, whose names they have not even deigned to 
preserve, and investing the single personage of Hercules 
with them. ‘The lapse of ages has not rendered us 
wiser in this respect. In our own time the public de- 
light in blending fable with history. In every career of 
life, in the pursuit of science especially, they enjoy a 
pleasure in creating Herculeses. According to vulgar 
opinion, there is no astrondmical discovery which is not 
due to Herschel. The theory of the planetary move- 
ments is identified with the name of Laplace; hardly 
is a passing allusion made to the eminent labours of 
D’Alembert, of Clairaut, of Euler, of Lagrange. Watt 
