BAILEY. | Methods of Analysis. 87 
is dissolved in water acidified with nitric acid, filtered if neces- 
sary, and treated with a few drops of ammonium chlorid, then 
with ammonium hydroxid and sodium hydrogen phosphate, by 
the ordinary methods. 
For the determination of Sulfuric Acid, a fresh portion of the 
water, from 100 cc. to 1000 cc., is acidulated with hydrochloric 
acid, filtered if necessary, and evaporated somewhat, if the 
amount of sulfuric acid issmall. The solution is heated to boil- 
ing and treated with as small a quantity of hot barium chlorid 
solution as possible to insure complete precipitation, and after 
standing for some time the precipitate of barium sulfate is fil- 
tered off. After weighing, as this precipitate is so liable to 
carry down with it other barium salts, it is boiled with hydro- 
chloric acid, and, after the addition of water, filtered, ignited, 
and again weighed. 
For the determination of Potassium and Sodium, the filtrate 
from barium sulfate is evaporated to dryness with hydrochloric 
acid, and silica is separated as usual. The solution is then 
treated with barium hydroxid, and, after standing for some 
time, is filtered. The filtrate is concentrated to small bulk and 
ammonium carbonate is added and the solution is again filtered. 
The filtrate is evaporated to dryness in a platinum vessel, and 
the residue is ignited at a low temperature. A few drops of 
water are added to the residue and a small piece of solid am- 
monium carbonate is added, and the solution is allowed to stand 
for ashort time. In case a precipitate, which would be carbon- 
ates of alkaline earths, is obtained, filter off, and evaporate the 
filtrate to dryness and again heat cautiously, and weigh. The 
residue consists of chlorids of the alkalies, and may be exam- 
ined for the individual alkalies by well-known processes. If 
lithium has been found by a spectroscopic test, a larger quan- 
tity of water must be used and a special determination of lith- 
ium made. 
For the determination of Sodiwm Carbonate, a liter of the wa- 
ter is evaporated on a water-bath to dryness, distilled water is 
added, and the solution is filtered, with slight washing of the 
