166 
SAMUEL BEOUeHTON. 
piyxanati:* 
FEANCIS NICHOLSON, F.Z.S. 
tht €<0«;iutl 
EOBEET DUKINFIELD DAEBISHIEE, B.A., F.O.S, 
WILLIAM BOYD DAWKINS, M.A., F.E.S., F.O.S. 
BALFOUE STEWAET, LL.D., F.E.S. 
ALFEED BEOTHEES, F.E.A.S. 
EEV. BEOOKE HEEFOED, 
CHAELES BAILEY. 
The following communication from Dr. Joule, F.R.S., 
was read by Mr. Baxendell : — 
“ Will you permit me, in reference to Mr. Howorth’s com- 
munication to the last meeting, to refer to my papers in the 
Phil. Trans., 1859, p. 91 and p. 183, in which experiments 
are described proving what had previously been shown by 
Sir W. Thomson to be corollaries to the dynamical theory of 
heat, viz. : — That the heat evolved by substances on being 
compressed is never exactly equivalent to the force of com- 
pression ; is generally very different therefrom ; while in the 
case of water taken between the limits 82° and 89° Fahren- 
heit, cold, not heat, is the result of compression. I cannot 
therefore, admit the axiom on which Mr. Howorth builds his 
ingenious theory.” 
