Progress oj Foreign Science. 323 



pretty long memoir, on tlie mode of analyzing the ores of nickel, 

 and on a new combination of nickel with arsenic and sulphur. 

 We shall reserve an account of this for our next Number, in 

 order to connect it with some more extended observations on 

 analysis, than we have room for in the present. Mr. Robiquet's 

 observations on the memoir of M. Berzelius, relative to the 

 composition of the triple prussiates or hydrocyanates, concerns 

 a subject too intricate and important to be lightly passed over. 

 We shall, therefore, bring it under review in the next Number. 



V. Organic Compounds. — Under this head we shall con- 

 sider all chemical combinations, which directly or indirectly 

 result from vegetable and animal organization. 



M. Dive, apothecary, of Mont-de-Marsan, has formed prus- 

 siate of potash by calcining in a covered crucible a mixture of 

 64 grammes of the dry powder of crude tartar, and 8 grammes 

 of pulverized sal ammoniac. He considers that the nascent car- 

 bon of the tartar, being presented to the nascent ammonia, dis- 

 engaged from the muriate by the potash, acts so as to form 

 cyanogen ; and that this action is favoured by the tempera- 

 ture, which weakens the combination of the hydrogen and azote 

 in the ammonia. The latter element being, in every point of the 

 mass, in immediate contact with particles of carbon, easily 

 unites to it, in the requisite proportions for forming cyanogen, 

 which is immediately fixed by the potash. The same gentleman 

 finds that a current of carbonic acid partially decomposes the 

 neutral tartrate of potash ; and he ascribes to this cause the 

 formation of the bitartrate in the juice of the grape during its 

 fermentation. Accordingly, on mixing neutrul tartrate with 

 fermentable materials, he found cream of tartar in the fermented 

 liquor*. 



In a report made to the Institute, 15th January last, by 

 M. M. Thenard and Berthollet, on M. Chevreul's 8th memoir 

 on Fat Bodies, we find the following results of their decompo- 

 sition by ignited oxide of copper. 



1. That the fat of man and the sow contain nearly the same 

 proportions of elements ; that mutton suet contains more carbon 

 and hydrogen ; and that in the three fats the carbon is to the 

 hydrogen, by volume, nearly as 10 to 18 ; which approaches to 

 the constitution of percarburetted hydrogen. 



2. That the steariucs contain less oxygen, and more carbon 

 and hydrogen than the claincs; and that the ratio of the car- 

 bon to the hydrogen in the stearines is 10 to 18, whilst it is a 

 little less in the claines. 



3. That the sum of the weight of the saponified fat, and the 



• Jnuni.iU P/ifiDii. (>(l. Id2l. I>. 487. 



