202 M. Vauquelin on the [March, 



potash. Redissolve the precipitate in aqueous ammonia, satu- 

 rate the excess of alcah by nitric acid, and precipitate the copper 

 and iron by a bar of zinc. Nothing will now remain in solution 

 but nickel, and, perhaps, a little cobalt. To obtain the nickel 

 free from this metal, precipitate it by aqueous potash, and the 

 cobalt will remain in solution. If this last precipitate be dried 

 and mixed with borax and exposed to a heat of 1 60° of Wedg- 

 wood, the metal will be reduced in a pure state. 



I am, Sir, your obedient servant, 



Nicholas Mill. 



Article XL 

 Chemical Examination of Cubebs, By M. Vauquelin.* 



CuBEBS are the fruit of the piper cubeba (triandria trigynia), 

 a perennial plant which grows in the Phihppine Islands, in Java, 

 Guinea, and the Isle of France. 



The cubebs which were employed for these experiments were 

 presumed to have been collected three years ; they were imported 

 by the Dutch, and had been in a warehouse in Paris for 18 

 months. 



These grains do not all possess the same colour; they are 

 rounded, and attached to a stalk : if they are examined 

 after being macerated in water, four coverings are discoverable; 

 the first is fleshy, and softens in water ; the second is of a grey 

 colour, and is nearly transparent ; the third is thin like the peel 

 of an onion, of a yellowish-brown colour ; the fourth is a very 

 thin white pellicle immediately covering the grains, some of 

 which are round, and entirely fill their covering ; others are flat 

 on one side, and rounded on the other ; others again are 

 wrinkled and covered with fatty matter ; and lastly, there are 

 some which are of a white colour. 



Many of these grains contained a white concrete oily matter, 

 and which had every appearance of a crystal. This concrete 

 matter melted in a silver spoon, remained fused, and without 

 emitting any odour. 



Seven hundred and seventy-two grains of bruised cubebs were 

 put into a retort with water, and subjected to distillation. The 

 water which came over was turbid, and covered with small 

 drops of volatile oil, the consistence of which was greater 

 than that of common volatile oils. It had a strong taste, which 



• From the Memoiret du Muieum d'Histoire Naturelle, torn, tu 



