[ 380 ] 
LI. Chemical Notices from Foreign Journals, By i. Arxin- 
son, Ph,D., F.C.S., Teacher of Physical Science in Cheltenham 
College. 
[Continued from p. 287.] 
EBRAY has described* some methods for obtaining -a 
number of artificial phosphates and arseniates, many of 
them identical'in form and composition with known minerals. 
When an insoluble carbonate is treated with excess of aqueous 
phosphoric acid, or arsenic acid, the carbonate is usually changed 
mto a crystallized phosphate or arseniate. The proportion of 
water of hydration varies with the temperature. With phos- 
phoric acid and carbonate of lime, a phosphate of lime is ob- 
tained of the composition PO®,2Ca0, HO+4HO. Ata tem- 
perature of 100° the phosphate PO®, 2CaO, HO is obtained. 
Arsenic acid and carbonate of lime at the ordinary tempera- 
ture give the body AsO®,2CaO,4HO, which is the mineral 
Haidingerite. 
In a similar manner the following bodies have been obtained :— 
At 70° phosphate of zinc. . . PO5,3Zn0O,4HO 
», 250° (ina sealed tube). . . PO*,3ZnO, HO 
» 70° phosphate of copper. . PO®, 3CuO0, 3HO 
» 70° arseniate of copper . . AsO°,2Cu0, HO, 3HO 
» 70° phosphate of manganese PO®*, 3MnO, 4HO. 
By acting on the insoluble phosphates of lime, magnesia, &e. 
with a metallic nitrate or sulphate, crystallized compounds are 
obtained, the composition of which varies with the temperature. 
At 70° phosphate of lime, PO®, 2CaO, HO, and arseniate of lime, 
AsO*,2CaO, HO, give with nitrate of copper the phosphate 
PO5, 8CuO, 3HO, and the arseniate AsO®, 3CuO, 4HO; and 
at a temperature a little above 100°C., 
The phosphate of copper, PO®, 4CuO, HO (libethenite) ; 
The arseniate of copper, AsO®, 4CuO, HO (olivenite). 
These latter bodies, which have the form as well as the com- 
position of the native minerals, are better obtained when the 
reaction is effected in a sealed tube at 140°—150°. 
At high temperatures (250°—270°) water transforms certain 
phosphates and arseniates into other well-crystallized species. 
Blue phosphate of copper, PO®,3Cu0,3HO, is transformed 
into magnificent crystals of libethenite ; and arseniate of copper, 
AsO®*, 83CuO, 4. HO, is changed into olivenite. 
Crystallized double phosphates are obtained by mixing the 
solutions of acid phosphates with metallic solutions. A solution 
of acid phosphate of lime, mixed with a solution of nitrate of 
* Bulletin de la Société Chimique, p. 134. 
