Intelligence and Miscellaneous Articles, 155 



Stearic acid, treated in the same manner, yielded a substance 

 which M. Bussy calls stearon, which resembles margaron in its ex- 

 ternal characters. When purified by crystallization in alcohol, it 

 melts at 182° Fahrenheit, and it is less soluble than margaron in al- 

 cohol and aether. It is composed of 



Carbon 84-78 



Hydrogen 1377 



Oxygen 1*45 



10000 

 It appears to be equivalent to stearic acid deprived of carbonic acid. 

 Oleic acid, treated in the same manner as the two preceding, 

 yielded also carbonate of lime as a residue, but the product distilled 

 was fluid from the commencement of the operation. This fluid was 

 not acid nor saponifiable, and appeared to be to oleic acid what 

 margaron and stearon are to the preceding acids. The difficulty of 

 obtaining pure oleic acid, and of separating oleon completely from 

 other liquid products, which the distillation may have yielded, has 

 hitherto prevented an analysis of it. — Ann, de Chim. et de Phys., 

 torn. liii. p. 398. 



SUPPOSED COMPOUND OF HYDROGEN AND PLATINA. BY M. 

 BOUSSINGAULT. 



Berzelius (Chimie, torn. iii. p. 64.) mentions a supposed compound 

 of hydrogen and platina, which may be thus prepared : Dissolve equal 

 parts of iron and platina in aqua regia ; the solution, deprived of its 

 excess of acid, is to be precipitated by ammonia. The precipitate, 

 when washed and dried, is to be reduced by hydrogen gas, in a 

 glass tube heated to low redness : muriatic acid, muriate of ammo- 

 nia, and the vapour of water are given out. The gas is to be passed 

 until the tube cools. The residue in the tube is a mixture of platina 

 and iron, which acts strongly as a pyrophorus : it requires some 

 dexterity to put it into muriatic acid without its inflaming. The 

 acid dissolves the iron with an abundant evolution of hydrogen gas ; 

 there remains a black powder, which is very heavy, and which only 

 requires well washing. 



This black powder, heated in an open vessel, inflames much below 

 a red heat : sometimes it deflagrates, and the matter is thrown out 

 in sparks; at other times the combustion takes place slowly, the 

 powder burning like amadou. When heated in a close vessel, a little 

 moisture appears on the cold part of it, and this circumstance gave 

 rise to the opinion of the existence of hydrogen in it ; but M. Bous- 

 singault considers it as unquestionably hygrometric moisture. 



During combustion 311 parts of the powder increased in weight 

 to 314, a circumstance which rendered the presence of iron ex- 

 tremely probable ; but it is remarkable that the combustion occa- 

 sions no change in the appearance of the powder ; though it is no 

 longer combustible, and 311 of the black powder, treated with boiling 

 nitric acid, left 249 of finely divided platina : the acid contained only 

 peroxide of iron, which amounted to ^th of the powder. It is 

 therefore very probable that the ignition is owing to the combustion 

 of a part of the iron which is combined with the platina. 



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