270 Mr. Brown on the Products of the Soda Manufacture. 



10. Carbonic add. 



By the addition of muriatic acid to the ball soda, sulphuretted hydro- 

 gen and carbonic acid gases were evolved, which were passed through a 

 strong solution of caustic barytes. The precipitated carbonate of barytes 

 was filtered as rapidly as possible, care being taken to keep it covered 

 with a plate of glass during the process : — 



Ball Soda. BaO C0 3 C0 2 C0 2 p.c. 



45-35 gave, 28*90 6-487 14304 



90-18 — 59-20 13289 14-736 



Average, 14-520 



11. Carbon. 



To determine the amount of carbon, a portion of the ball was heated 

 with muriatic acid, and the solution evaporated to dryness. Dilute acid 

 was then added, and the insoluble matter thrown on a filter, which had 

 been previously dried at 212°, and weighed. The total amount of carbon, 

 silica, and sand, was thus ascertained. The whole was then ignited and 

 weighed, and from the loss the per centage of carbon was calculated: — 



Ball Soda. Insol. Matter. Carbon, p.c. 



100 gave, 15*941 which lost, on ignition, 7-998 



12. Water. 



The soda ball was dried at 212°, and the amount lost estimated: — 

 Ball Soda. Water. Water, p.c. 

 50-00 lost, 0-35 0-700 



Whilst washing out the soluble salts, it was observed that the filtered 

 solution was of a greenish colour, and upon boiling it a green coloured 

 substance was deposited, after which the supernatant liquor became 

 perfectly colourless. Upon examining this precipitate, it was found to 

 consist principally of silica and alumina, with a little lime. From this 

 it was concluded to be artificial ultramarine, which i3 frequently found 

 in the crevices of the ball furnaces, and which, when dissolved in caustic 

 soda, yields a green coloured solution, precisely the same as that men- 

 tioned above : — 



