The term alkali is employed in a technical sense for the carbonate and hydrate (of sodium), but since in the Leblanc process the manufacture of sodium sulphate necessarily precedes that of the carbonate, we include this as well as the manufacture of hydrochloric acid which is inseparable from it.
From that time onward the Leblanc process spread more and more, and for a considerable period nearly all the alkali of commerce was made by it.
The fuel required is less than half the amount used in the Leblanc process.
The only way in which the Leblanc process could still hold its own was by being turned in the direction of making caustic soda, to which it lends itself more easily than the ammonia-soda process; but the latter has invaded even this field.
One advantage, however, still remained to the Leblanc process.
