C40 



SCIENTIFIC RECORD FOR 1883. 



compiled the following table of the present soda production in various 

 countries : 



Present soda production of the world. 



From this it is evident that the total quantity of soda now being man- 

 ufactured annually is nearly 709,000 tons, of which more than 163,000 

 tons are made by the ammonia process. 



Although the ammonia process was first proposed by Dyer & Hem- 

 ming more than forty-seven years ago, it is less than seventeen years 

 since it has been carried on industrially. Iu 1866 Ernest Solvay, of 

 Brussels, began to produce soda by the ammonia process at his works 

 near Charleroi; in 1866-'07 he manufactured 179 tons; this increased 

 to 11,580 tons in 1876-'77, and 53,400 tons in 1881-'82. Mr. Weldon 

 estimates that about 40 per cent, of the total soda now made on the con- 

 tinent is produced by the ammonia process. In England, also, the com- 

 petition of the ammonia process has attained a magnitude which is 

 alarming the makers of Leblanc soda. 



Another circumstance is injuriously affecting the Leblanc system, 

 viz, the loss of profits on the by-products. Originally, soda was the 

 only commercial product of the process, the hydrochloric acid being 

 turned to'no account. In time a demand grew up for chlorine, and the 

 hydrochloric acid began to be utilized profitably ; then the soda ceased 

 to be profitable, and became a by-product in the manufacture of chlo- 

 rine ; next, this source of profit failed and recourse was had to the " burnt 

 ore" or "pyrites cinders" obtained as a secondary product by roasting 

 pyrites for sulphuric acid, and which is treated for copper, silver, and 

 to some extent for gold. The Eio Tinto Company, of Spain, owning 

 enormous deposits of pyrites, intend establishing in France and else- 

 where works for manufacturing Leblanc soda, and expect to derive their 

 profits neither from the soda nor from the chlorine, but from the copper 

 and the residual oxide of iron. 



The extension of the ammouia process of manufacturing soda has led 

 to devising plans for obtaining ammonia itself more cheaply, and it is 

 now collected from coke ovens in France and in England, and from 

 blast furnaces in Scotland. From the latter source alone Mr. Weldon 



