414 JOSEPH FOURIER. 
pletely verified, they have become laws of nature; they 
point out latent properties of caloric which could only be 
discerned by the eye of the intellect. 
In the second question treated by Fourier, heat pre- 
sents itself under anew form. There is more difficulty in 
following its movements; but the conclusions deducible 
from the theory are also more general and more impor- 
tant. 
Heat excited, concentrated into a certain point of a 
solid body, communicates itself by way of conduction, 
first to the particles nearest the heated point, then grad- 
ually to all the regions of the body. Whence the problem 
of which the following is the enunciation. 
By what routes, and with what velocities, is the prop- 
agation of heat effected in bodies of different forms and 
different natures subjected to certain initial conditions ? 
Fundamentally, the Academy of Sciences had already 
proposed this problem as the subject of a prize as early 
as the year 1736. Then the terms heat and caloric were 
not in use; it demanded the study of nature, and the 
propagation OF FIRE! ‘The word jire, thrown thus into 
the programme without any other explanation, gave rise 
to a mistake of the most singular kind. ‘The majority of 
philosophers imagined that the question was to explain 
in what way burning communicates itself, and increases 
in a mass of combustible matter. Fifteen competitors 
presented themselves ; three were crowned. 
This competition was productive of very meagre re- 
sults. However, a singular combination of circumstances 
and of proper names will render the recollection of it 
lasting. 
Has not the public a right to be surprised upon read- 
ing this Academic declaration: “the question affords no 
