344 SALTS 



colour of no great depth of shade, and destitute 

 of beauty. It is tasteless, insoluble in water, 

 and not altered by exposure to the air. It does 

 not alter vegetable blues, but dissolves in acids 

 with a strong effervescence. 



8*125 grains of this salt were exposed to a red 

 heat in a platinum crucible ; there remained a 

 black powder weighing 4'75 grains. It was per- 

 oxide of cobalt, and equivalent to 4'25 grains of' 

 protoxide : hence, the constituents of the salt are 



1 atom carbonic acid 2 -75 



1 atom protoxide of cobalt 4-25 

 1 atom water 1-125 



8-125 



Phosphate, 5. Phosphate of cobalt. This salt was pre- 

 pared by dissolving carbonate of cobalt in phos- 

 phoric acid and mixing the solution with alco- 

 hol. A copious precipitate falls, which was col- 

 lected on a filter, and edulcorated first with 

 alcohol and then with water. It was gelatinous, 

 and had a fine crimson colour. When dried, it 

 concreted into a hard dark red matter, which 

 reddened vegetable blues. ] grains of it, when 

 heated to redness, lost very nearly 2'25 grains ; 

 hence, I consider the salt as composed of 



1 atom phosphoric acid 3-5 



1 atom protoxide of cobalt 4'25 



2 atoms water 2-25 



10 



