Chemical Instruments and Operations. 279^ 



10. Application of the Volumescope to the analysis of car- 

 bonic oxide, so as to shoiv that the result confirms the the- 

 ory of volumes. 



Carbonic oxide requiring for its saturation half its bulk of 

 oxygen ; in order to analyse it in the apparatus last describ- 

 ed, after the preliminary preparations mentioned as necessa- 

 ry, in case of the gaseous elements of water, introduce two 

 volumes of carbonic oxide, and one of oxygen gas, and ig- 

 nite the platina wire. A feeble explosion will take place, 

 and one volume will disappear. To complete the analysis, 

 by means of a funnel screwed on to the cock inserted into the 

 perforation in the mahogany block at the top of the eudiom- 

 eter, lime water may be introduced, and thus all the carbon- 

 ic acid, generated by the combustion of the carbonic oxide 

 with the oxygen gas, may be absorbed. Of course, if the 

 gases be pure, the absorption will be complete. It might 

 perhaps be found preferable to introduce lime water by 

 means of the syphon and bag, fig. 5. 



11. ACCORDANCE OF THE ANALYSIS OF OLEFIANT GAS WITH 

 THE THEORY OF VOLUMES, ILLUSTRATED BY THE VOLUME- 

 SCOPE. 



As a volume of olefiant gas consists of two volumes of hy- 

 drogen, and two volumes of carbon vapour, if it be exploded 

 with an excess of oxygen, say four volumes, all the hydrogen, 

 and one volume of oxygen, will be converted into water. 

 Meanwhile, two volumes of oxygen, uniting with two of car- 

 bon vapour, will constitute two volumes of carbonic acid. 

 These may be absorbed by lime water introduced as in the 

 case of carbonic oxide. It follows that one volume of oxy- 

 gen will remain. 



12. ANALYSIS OF A MIXTURE OF CARBONIC OXIDE, WITH ONE 

 OR MORE OF THE GASEOUS COMPOUNDS OF CARBON WITH 

 HYDROGEN. 



If defiant gas be present, it may be condensed by min- 

 gling, in any tall, narrow vessel protected from light, over 

 water, one hundred measures of the mixture, with two hun- 

 dred measures of chlorine ; and at the end of about a quar- 

 ter of an hour, agitating the residue with a caustic alkaline 

 solution, to remove any excess of the last mentioned gas.* 



* See Traite de Chimie par Thenard, vol. v. page 34. 



