20 ANIMAL ACIDS DESTITUTE OF AZOTE. 



the ether are dissolved separately in boiling alcohol, and the so- 

 lutions are left to spontaneous evaporation. These solutions and 

 crystallizations are repeated two or three times. Two sets of 

 crystals are obtained. The one in groups of round tubercles is 

 the adipic acid ; the other in elongated plates is the lipic acid. 



Adipic acid thus obtained is in tubercles composed of needles 

 radiating from a centre. Laurent always obtained it of a brown 

 colour, which enabled him to distinguish it from pimelic acid, 

 which is white. The spherules of which it is composed are softer 

 and longer than those of pimelic acid. After being dried at 212, 

 it melts when heated to 293, and, like pimelic acid, it may be 

 readily sublimed in beautiful crystals. It is almost equally so- 

 luble in ether, water, and nitric acid. 



Adipate of ammonia crystallizes in needles. It does not pre- 

 cipitate chlorides of barium, strontium, and calcium; nor sulphates 

 of magnesia, manganese, nickel, cobalt, and copper ; nor ace- 

 tate of lead. It precipitates perchloride of iron brick-red. When 

 nitrate of silver is dropt into adipate of ammonia, no precipitate 

 appears at first ; but when a sufficient quantity of nitrate has 

 been added, a white precipitate falls. 



M. Bromeis analyzed adipate of silver, and found it compos- 

 ed of 



Adipic acid, . 39-39 or 18-846 

 Oxide of silver, 60-61 or 29. 



100-00 

 The adipate of barytes was composed of 



Adipic acid, . 48-58 or 17-95 

 Barytes, . . 51-42 or 19. 



100-00 



Bromeis found the constitution of the hydrous acid to be 

 Carbon, . 49-56 



Hydrogen, . 7.06 



Oxygen, . 43-38 



100- 



The analysis of adipate of silver agreed with this ; only that 

 there were two atoms of water in the acid. They had been dis- 

 placed by the oxide of silver. Now, the formula that accords 



