21 
Ordinary Meeting, December 16th, 1862. 
E. W. Binney, F.R.S., F.G.S., President, in the Chair. 
Dr. Joule read the following letter addressed to himself : — 
“ Varagnes, near Annonay, Ardeche, France, 
“ November 25, 1862. 
“ Dear Sir, 
“ I am much obliged to you for the disinterestedness 
you have maintained in reference to the discovery of the great 
principle that my uncle, the celebrated Montgolfier, revealed 
to me some sixty years ago. Since that time I have passed 
my whole life in studying this question. 
“Much merit is due to you, sir, for your defence of another’s 
rights, especially after the compositions which you have pub- 
lished, and are, without doubt, the best explanations yet 
written of the great principle so continually occupying you, 
myself, M. Grove, M. Mayer, and many others. Among the 
latter there are many Avho endeavour to persuade the public 
(every one in his interest) that the world owes the great 
advancement of the dynamical theory of heat solely to their 
works ; but the public do not like being led in this kind of 
logic, and look with indifference upon the pretended authors 
of these discoveries, at the same time raising the merit of 
those, like yourself, who take a pleasure in rendering justice 
to those who wait patiently until just and impartial men 
judge them by their works and not by their words. 
“ For more than sixty years I have studied the question of 
identity of caloric and movement, and yet have perceived 
no advancement of this subject; nothing that either has been 
said or written has helped me towards the conviction I have 
arrived at. Indeed, almost all the experiments since then 
have proved this a fact (which formerly no one endeavoured 
to contest), viz., that immediately movement disappears, heat 
is produced, reciprocally. We cannot, however, praise too 
much your studies, and those of the physicists who have 
Pbockedings — Ltt. and Phii.. Society— -No. 4. — Session 1862-3. 
