148 Scientifie Intelligence. 
the latter to be 64 fig vibrations more acute and, without 
for my forks giving 512 single vibrations he has found 516’7 only, 
with the tonometer which he used. Whence it would seem that 
the fundamental note of this latter instrament had become more 
nearly exact than that of the tonometer aceite’ by M. Helm- 
holtz, since the number of its vibrations is 507°3. This note, 
however, “ remains ae distant from its true ‘value 
e fact that M. Hel phen succeeded, with an instrument of 
self a little practice in the manipulation of acoustic instruments, 
efore la ing so slightingly the results obtained by Lis- 
sajous, by Despretz, by Helmholtz, by Mayer, etc., etc., and 
before seeking to deride discredit upon the labors of a constructeur 
who had no reason to expect so valde an attack. 
26 Rue de Pontoise, Paris, J une 5th, 1877 
Ov 
@) 255-97, (8) 255° 9, (4) 255°92, (5) 256-02, (6) 256°02. The 
ork’s vibrato ory BS eriod is accelerated or diminished sztor part 
by a difference of t —Eps. | 
SCIENTIFIC INTELLIGENCE. 
I. CHEMISTRY AND Prysics. 
of electrolytic gas. Since, hitherto, according to him, this term 
has not been defined with sufficient exactness, Than uses “ heat of 
