Intelligence and Miscellaneous Articles. 429 



acid, and one part of pyroxylic spirit. With a gentle heat a gas is ob- 

 tained, which may be collected over water, and which is pure chlo- 

 rhydrate of methylene. The water retains any gaseous admixtures. 



Chlorhydrate of methylene is a colourless gas which has an sethereal 

 odour and a sweet taste. It burns with a white flame in the middle 

 and a green one at the edges • water at 60° dissolves 2*8 times its 

 volume of this gas. In its gaseous state, or dissolved in water, it is 

 a perfectly neutral compound, not acting either upon litmus or nitrate 

 of silver ; its properties perfectly resemble those of muriatic aether. It 

 is composed of 



1 atom of methylene 1/8-05 or 28*12 



1 atom of chlorhydric (muriatic) acid .... 455*15 — 71*88 



633-20 100*00 



At a red heat this substance is decomposed into muriatic acid and a 

 carburetted hydrogen gas. 



Hydriodate of Methylene.— This is very readily procured by distilling 

 one part of phosphorus, eight parts of iodine, and twelve or fifteen 

 of pyroxylic spirit. The iodine is to be dissolved in the pyroxylic 

 spirit, and the phosphorus is to be gradually added to it in a retort. 

 Rapid action, accompanied with heat and the production of hydride 

 acid, soon takes place ; as soon as the ebullition is over, the remainder 

 of the phosphorus is to be added with agitation • the retort is soon to 

 be heated, and distillation is to be continued as long as an aethereal 

 liquor is produced. 



The residue consists of phosphorous acid, phosphomethylique acid, 

 and phosphorus, and it is quite colourless. The liquor obtained in 

 the receiver is composed of pyroxylic spirit and hydriodate of methy- 

 lene j the latter is separated by water, which immediately precipitates 

 it • the weight of it is nearly equal to that of the iodine employed. 

 This hydriodate is not, however, pure; it must be distilled in a water 

 bath from chloride of calcium and great excess of massicot. This 

 hydriodate is, when pure, colourless and slightly combustible ; it burns 

 only in the flame of a lamp, and then yields abundant violet vapours. 

 Its density is 2237, and it boils at from 105° to 125° Fahr. The den- 

 sity of its vapour is 4*883. It is composed of 



1 atom of hydriodic acid 1592*00 or 1006 



1 atom of methylene .. , 178*05 — 89*94 



1770*05 100-00 



(To be continued.) 



COMPOSITION OF PYROMUCIC ACID. 



M. Boussingault states that M. Houton-Labillardiere, who first 

 removed all doubt as to the existence of the pyromucic as a peculiar 

 acid, found its composition to be 



Carbon 52*1 



Hydrogen 2*1 



Oxygen 45*8 



1000 



