140 
SPECIFIC HEAT OF GASES. 
Apparatus 
and f-Aoeri- 
ments to de- 
termine the 
specific lieat 
ef the uases 
A Memoir on the Specific Heat of the Gases- By Messrs. F. 
Delaroche Beuard. To which the Prize proposed by 
the Class of Mathematics and Natural Philosophy of the 
Institute of France, in the year 1811, has been awarded. 
Abstracted by the Authors. 
(Continued from />.284. Vol. XXXF) 
\ 
Section II. 
Apparatus used to cause a regular current of hot gas to pass 
through the Calorimeter 
I N order to obtain a regular current of gas, we made use of 
the gazometer of Wollaston ; but in order to heat the 
calorimeter to the point at which its temperature would have 
been stationary, very considerable quantities of gas would have 
been required, which would have in some instances been very 
expensive, and at all events the dimensioris of the gazometcrs 
would have required to be very great. To obv iate these incon- 
veniences, gazometers were constructed of tire same kind, and H 
so disposed as to afford two similar currents of gases j and 
these instruments were so disposed, that the current from one 
of them was admitted into the other, without disturbing the 
regularity of the current. The gas from one gazometer, before 
it arrived at the second, was made to pass through a tube of 
more than one metre in length, included in another larger 
tube in which the vapour of water was continually circulating. 
In this tube the gas was heated, whence it was passed through 
the calorimeter, and thence into the second gazometer. When 
the lirst gazometer was thus quite emptied, the gas was passed, 
back again, and by means of cocks properly tii>persed, again 
became heated in its course through the tube surrounded by 
boiling water, and was a second time passed through the calori- 
meter. I 
