88 CONTRIBUTIONS TO CHEMISTRY AND MINERALOGY. [bull. 167. 
Tetraphosphonitrilic chloride forms colorless, brittle prisms, not 
easily wet by water, and therefore having a strong tendency to float. 
Superficially, these are not always to be distinguished from those of 
triphosphonitrilic chloride, but in a general way it may be said that 
they tend to be much smaller, and are to be measured by millime- 
ters rather than centimeters, and that they tend to vary toward an 
acicular rather than a tabular form. In alcohol and in benzene it is 
much less soluble than P 3 N : ,C1«. Hot concentrated sulphuric acid dis- 
solves it, and, on boiling, much hydrochloric acid is evolved, but some 
of the substance sublimes out unchanged. It may be recrystallized 
from glacial acetic acid; on boiling this solution with zinc dust a little 
hydrogen phosphide is given off, and the solution contains ammonia. 
It is noticeably volatile at its fusing point, its vapor having an odor 
suggesting, but perceptibly differing from, that of triphosphonitrilic 
chloride, and less aromatic. The fused substance solidifies to a mass of 
nearly parallel needles, while triphosphonitrilic chloride gives trans- 
parent plates. As mentioned above, its volatility with steam is com- 
paratively slight. If boiled for some time in contact with air, a minute 
amount of substance is formed, which swells enormously to a clear 
gelatinous mass in benzene. Alcohol converts it slowly into an oily 
ether, which aqueous ammonia, on warming, saponifies to tetrameta- 
phosphimic acid. 
Action of water on tetraphosphonitrilic chloride. — In its chemical 
behavior it resembles triphosphonitrilic chloride. It is scarcely acted 
on by boiling water, yet on prolonged boiling a minute amount of tetra- 
metaphosphimic acid is formed; aqueous fixed alkalies are without 
perceptible action, while alcoholic alkalies decompose it easily, but the 
product is mainly something else than tetrametaphosphimic acid. 
A smooth decomposition is effected by dissolving in ether and shak- 
ing protractedly with water. The first products of this action consist 
of chlorhydrines, which remain dissolved in the ether, are crystalline, 
and readily soluble in cold water, from which solution tetrametaphos- 
phimic acid is rapidly deposited in the form of thick needles; the same 
acid is the final product of the action of water on the ether solution. 
The action of water proceeds rather more rapidly than in case of 
triphosphonitrilic chloride, but many days are required for complete 
decomposition. The small amount of material at present in my pos- 
session made it unadvisable to attempt to isolate any of the chlorhy- 
drines, of which seven are theoretically possible. 
Tetrametaphosphimic acid, P 4 N 4 OaH 8 + 2H 2 0, will be described in a 
separate section. It may be remarked here preliminarily that it has 
highly characteristic properties, is highly crystalline, very difficultly 
soluble in cold water, and much less soluble in dilute acids; that it 
readily decomposes soluble chlorides, nitrates, and sulphates, and gives 
three series of salts, in which, respectively, one- fourth, one half, and all 
the hydrogen is replaced by metal; many of these show characteristic 
