178 Dr. Hare on the Construction afid Applications of the 



When there is a copious supply of the gas to be examined, 

 the barometer-gauge eudiometer may.be used advantageously; 

 as much larger quantities of gas may be exploded in it than 

 could be exploded in the same time in the sliding-rod eudio- 

 meter. 



In order to render the process with the barometer-gauge 

 eudiometer safe, the quantity introduced in the first instance 

 should be as small as can be ignited. Afterwards successive 

 portions may be introduced and exploded until the receiver 

 be nearly full of the residual gas. That this operation may 

 be still more secure, I propose to employ, as a receiver, an 

 iron bottle (such as are used to hold mercury) surmounted by 

 a very stout glass tube, in which the platina wire may be si- 

 Then M + O will constitute the whole weight of the products. 



And M + O— C the whole weight of water, 

 g 



Also —(M-fO— C) = all the oxygen in the water. 



8 C 



-rr-will be all the oxv!;en in the carbonic acid. 

 11 • " 



3 C 



-pj- all the carbon in that acid, and consequently the whole con- 

 tained in the products. 



8 8 r 



— (M+O— C)+ — - will be all the oxygen in the products. 



8 8 P 

 And — (M-l-0— C)H ^—0 will be that portion of oxygen which 



existed previously in the gas, which call X. 



We have therefore the following equation, 



8M+8 0-8C 8C „ ^vK- V. 1 .u II 



X = ■ -4- O. W hich may be thus reduced. 



" 9 ^ 11 



88M + 88 0-88C+7'2C 

 X - 99 



, _ 88 M +88 0-16 C 



88 M+88 O- 16 C-99 O 



X 



99 

 88M-16C-11 O 



99 

 It follows from the atomic weights, and the premises, that 



~ — = the carbon in carbonic oxide. And X H = weight of car- 



4 4 



bonic oxide. 



Also — '■ = the carbon united to hydrogen. 



11 4 



3t^ 3X M-+0-C • , r ■ J u I 



f^^^ .r J. — J— — weight Ot carburettcd hydrogen. 



114 9 



tuated, 



