of Benzoaie of Copper. 5 



its bulk was exceedingly diminished, and probably a consider- 

 able quantity of it decomposed. The portion insoluble in al- 

 kalies dissolved very readily in hot alcohol, and crystallized 

 on cooling in long snow-white crystals. These were melted 

 and subjected to analysis in the usual way. 



"I. 0'581 grm. gave 1*675 carbonic acid and 0*265 water. 

 "II. 0-5655 gave 1*633 carbonic acid and 0*258 water. 

 I. II. 



Carbon . 78*55 7^*76 



Hydrogen 5*06 5*06 



Oxygen. 16*39 16*18 



100*00 100*00 



" When that portion of the distillate which dissolved in the 

 potash-ley was boiled in a retort, water passed over mixed 

 with a few drops of an oily matter, which was not more closely 

 examnied. What remained in the retort, on being saturated 

 with sulphuric acid, became a mass of shining crystals, which 

 closely resembled benzoic acid. When the brownish-red co- 

 loured salt which remained in the retort was treated with sul- 

 phuretted hydrogen gas, it became very hot and was covered 

 with a sublimate of white crystalline needles, while hydrogen 

 gas was given off and sulphuret of copper remained. This 

 sublimate was soluble both in alcohol and water, and crystal- 

 lized on cooling in long shining needles, having a strong acid 

 reaction and an appearance quite different from that of ben- 

 zoic acid. The acid can also be extracted from the copper 

 salt by means of ammonia. It readily crystallizes when the 

 ammonia is saturated with acetic acid, and the copper is preci- 

 pitated by sulphuretted hydrogen." 



The quantity of the neutral crystalline compound which I 

 subjected to examination was obtained from benzoate of cop- 

 per prepared exactly in the way already described by Dr. 

 Ettling. The dried salt was distilled in a copper retort over 

 the naked fire. The amount of the neutral body which the 

 salt yielded was pretty considerable ; it came over in oily drops 

 which condensed into a pasty crystalline mass as the receiver 

 cooled. The products of the distillation were benzoic acid, 

 the neutral crystalline body, and a small quantity of a heavy 

 oil, in appearance and smell much resembling benzone. The 

 pasty mass was first strongly pressed between folds of blotting- 

 paper to remove adhering oil. The crystals were then re- 

 peatedly agitated with a hot solution of carbonate of soda in 

 great excess, which removed the benzoic acid, the amount of 

 which considerably exceeded that of the neutral body. It is 



