Intelligence and Miscellaneous Articles. 77 



extremely fine, levigation being useless, must be mixed with from 4 

 to 6 times its weight of pure carbonate of barytes, and placed in a 

 platinum crucible ; this is then inclosed in a Hessian crucible covered 

 and luted, which placed on any convenient support in the furnace 

 must be heated to whiteness, and kept at that temperature for from 15 

 to 20 minutes : a perfectly fused mass is obtained, which dissolves with 

 facility in diluted muriatic acid. — Annales de Chimie, December 1835. 



ON SOME NEW COMBINATIONS OF CARBOHYDROGEN OR 

 METHYLENE. 

 MM. Dumas and Peligot have succeeded in obtaining some new 

 combinations of carbohydrogen. The first, hydrofluate of carbohy- 

 drogen, may be obtained by gently heating a mixture of fluoride of 

 potassium and sulphate of carbohydrogen ; sulphate of potash is formed, 

 and a gas evolved which collected over water is deprived of all foreign 

 substances, and is then pure hydrofluate of carbohydrogen. It is 

 colourless, of an agreeable aethereal odour, and burns with a flame 

 similar to that of alcohol, but rather more blue. By its combustion 

 hydrofluoric acid is formed, the vapours of which are diff"used in the 

 air. It is slightly soluble in water, 100 parts of water at 60° Fahr., 

 dissolving 1 66 of this gas. The analysis of this gas indicates its com- 

 position to be 



One volume of carbohydrogen 0'4904 



One volume of hydrofluoric acid 0'6788 — M692 



According to this, hydrofluate of carbohydrogen, like the hydrochlo- 

 rate of that base, contains as well as hydrochloric aether, 1 vol. of acid 

 and ] of carburetted hydrogen condensed into one volume. 



When a mixture of pyroxylic spirit, nitric acid, and nitrate of silver 

 is boiled in the proportions used in making fulminating silver, or in 

 any other proportion, no action takes place before the evaporation 

 of -i^trths of the liquor, unless the nitric acid is very strong and the 

 operation is conducted in a retort, when amongst the volatile products 

 abundance of nitrate of carbohydrogen is found. Towards the end of 

 the operation, when the solution is so concentrated that the nitrate 

 of silver would become solid by cooling, by continuing the ebullition 

 lively action takes place, much hyponitrous acid is liberated, and there 

 is deposited a white powder. This detonates with difficulty by a blow, 

 and deflagrates feebly when placed in contact with hot coals, from 

 which MM. Dumas and Peligot at first considered that it contained 

 fulminating silver ; but a more attentive examination showed it to be 

 oxalate of silver. 



By adding pyroxylic spirit to the acid nitrate of mercury, a consi- 

 derable quantity of a yellowish white and resinous-looking substance 

 is immediately deposited, which by boiling for a long time with con- 

 centrated nitric acid, produces a white powder which is perfectly pure 

 oxalate of mercury. 



On an analysis the substance formed by the immediate action of 

 pyroxylic spirit on nitrate of mercury gave from 1-025, water 0-024 

 and carbonic acid 0-180. 0600 gave by protochloride of tin, and 



