Technical Chemistry. 285 
4 pure gas. It is remarked however by Mr. Crookes® that the mixed gas 
of Webster’s process is as pure as can be used in the arts unless in the 
metallurgy of the platinum metals. “3 
5 
: 1O+-Al,O,, and free carbonic acid. An excess of chalk in the 
ae is found to be advantageous, as it renders the charge less fusible. 
© operation is conducted in a reverberatory furnace similar to those 
Usually employed in alkali works. The compound of alumina and soda 
: inolved in hot water and subsequently decomposed by carbonic acid, 
th Mention is made of the economic application of the large amount of 
® fluorid of calcium produced in the above operation—aside from its 
Use for making fluohydric acid, it unquestionably can be advantageously 
Plied as a flux in many metallurgical operations. G. J. B 
3 Chem. News, vi, 221. 
Aw. Jour. Sct.—Szconp Series, VoL. XXXV, No. 104—Maron, 1863. 
37 
