106 
CONTRIBUTIONS TO CHEMISTRY AND MINERALOGY. 
[BULL. 107. 
If a solution of sodium trimetaphosphimate, to which exactly 3 molec- 
ular weights caustic soda, or an excess of ammonia, have been added, be 
dropped into an excess of dilute silver nitrate, a light sulphur-yellow, 
voluminous, and amorphous precipitate is formed, which may be washed 
with cold water without change, and does not change color on drying. 
This likewise contains 6 atoms of silver, and is insoluble in ammonium 
nitrate. If boiled with a trace of silver nitrate it remains unchanged; 
but if boiled with pure water it changes slowly, or if sodium trimeta- 
phosphimate or ammonium nitrate be present, in a few moments, into 
the same orange-red, crystalline powder above mentioned. 1 On one 
occasion a deep red crystalline powder was obtained, but the conditions 
for its formation could not be determined. The following figures resulted 
from the analyses of these salts, in every case dried at 100° : 
P. 
Ag 
Calculated for 
P 3 N 3 7 H 2 Ag 6 . 
10.39 
72.21 
Calculated for. 
P 3 N 3 G Ag 6 . 
10.59 
73.69 
WHITE SALT (AMORPHOUS). 
Found. 
Remarks. 
Lowest. 
Highest. 
Mean. 
p 
Ag 
10.54 
71.04 
11.28 
71.93 
10.92 
71.58 
4 preparations. 
Mean ratio P : Ag = 3 : 5.66. 
YELLOW SALT (AMORPHOUS AND CRYSTALLINE). 
10. 44 7 preparations. 
72. 53 Mean ratio P : Ag = 3 : 5.99. 
ORANGE-RED SALT (CRYSTALLINE). 
P . 
A- 
10.69 
72.38 
10.91 
72.91 
10. 81 ! 5 preparations. 
72. 61 Mean ratio P : Ag = 3 : 5.79. 
RED SALT (CRYSTALLINE). 
Ag 
10. 65 1 preparation. 
73.18 Ratio P:Ae = 3: 5.93. 
' This is seen to crystallize from the liquid, so that temporary solution must take place. 
