Sil. Potassa, Calc.

But the herb under consideration contains a relatively larger proportion of inorganic salts, as those of lime, potassa, and ammonia,and especially of highly nitrogenized substances; which explains why tobacco is so exhausting a crop to the soil, and why ashes are among its best fertilizers.

Ferrous oxalate works quite well with plates of that kind; so do soda and potassa developers.

More pleasant to work with is Dr. Stolze's potassa developer.

In manufactories where no refining is done, the crude potassa in powder is pushed on to a prolongation of the apparatus which is cooled by means of water, and is removed from time to time with shovels by the workmen, so that the orifice of the boiler remains constantly covered externally by the mass, and that the air cannot re-enter the apparatus.

After this, steam is injected directly through the tube, k, in order to distill the acetic acid that still remains in the residuum, and which passes thus through the tube, e, into the worm, h, and flows into the two-necked bottle, S. There may be added to the boiler, C, certain materials for purifying the acetic acid, such as permanganate of potassa or acetate of soda, so as to obtain an absolutely pure article.

Carbonic acid gas maybe for this purpose developed by the chemical decomposition of bicarbonate of potassa (saleratus), or bicarbonate of soda, by some acid such as sour milk, hydrochloric acid, tartaric acid, nitrate of potassa, or the acid phosphate of lime.

Carbonic acid gas maybe for this purpose developed by the chemical decomposition of bicarbonate of potassa (saleratus), or bicarbonate of soda, by some acid such as sour milk, hydrochloric acid, tartaric acid, nitrate of potassa, or the acid phosphate of lime.