Intelligence and Miscellaneous Articles, 221 



ON HYDROBROMATE OF CARBOHYDROGEN (METHYLENE). 



The hydrobromate of carbohydrogen discovered by M. Bonnet 

 is a colourless and extremely volatile liquid of an agreeable and pe- 

 netrating odour. Although water causes a precipitate in a solution 

 of it in pyroxylic spirit, yet a considerable quantity is retained in so- 

 lution; it is also soluble in alcohol and aether, from which it is preci- 

 pitated by water. It is decomposed by heat. The constitution of 

 this compound is represented by the formula Br 2 H 2 , C 4 H 4 , — 

 V Institute Feb. 1837. 



ON THE PREPARATION OF SULPHURET OF CARBON. 



M. Mulder directs, in an iron bottle in which mercury is im- 

 ported, that besides the hole which is already there, another should 

 be bored near it. Into the first of these openings a copper tube 

 bent twice at right angles is to be screwed, and into the second a 

 straight tube, also of copper, is to be introduced. Then the bottle is 

 to be filled with pieces of charcoal, recently heated to redness, of 

 such a size that they can easily pass down the tube. After having 

 firmly screwed in the straight and curved tubes, place the bottle in 

 a furnace and heat it, after having closed the opening of the furnace 

 with a stone cut in halves to prevent inconvenience to the operator 

 from the ascending heat. 



Adapt to the curved tube a WoulfF's bottle half rilled with water 

 and surrounded with a freezing mixture, and when the iron bottle 

 is sufficiently heated, introduce bj r the straight tube fragments of 

 sulphur and immediately close the mouth of the tube with a plug ; 

 the sulphur fuses, and falling upon, penetrates the pieces of charcoal, 

 and when the sulphur is gradually added, but little gas is evolved 

 and abundance of sulphuret of carbon obtained. — Journal de Phar- 

 made, Jan. 1837. 



SOLUBILITY OF OXIDE OF LEAD IN WATER. 



M. De BonsdorfF states that oxide of lead is entirely soluble in 

 water when it is formed by the action of damp air, or by the de- 

 composition of nitrate of lead by the application of heat*. — L'ln- 

 stitut, May 1637. 



ANHYDROUS CAMPHORIC ACID, CAMPHOVINIC ACID, AND CAM- 

 PHORIC iETHER. 



According to M. Malaguti, crystallized camphoric acid obtained 

 by the prolonged action of nitric acid on camphor, and possessing 

 all the properties of pure camphoric acid, affords by combustion with 

 oxide of copper : 



Carbon 60-20 



Hydrogen 8-00 



Oxygen 31-79 



which indicates the formula C 20 H 8 O 4 . 



* On this subject see Lond. and Edinb. Phil. Mag., vol. v. p. 81. 



