Extracts from Berzelius's Annual Report for 1843. 193 



easily reduced into powder. It is infusible and insoluble in cold water 

 and in warm water, in a cold solution of an alkali, in nitric, hydrochlo- 

 ric and sulphuric acids, and in aqua regia. It is not altered by hydro- 

 gen at the temperature of incandescence ; the vapor of water on the 

 contrary decomposes it at a temperature below red heat— boracic acid, 

 potash, and ammonia, being the products ; all those bodies which retain 

 water at an elevated temperature decompose it, as caustic potash, phos- 

 phoric acid, lime, &c. It is probable that its composition is KBN. By 

 heating the cyanides of the different metals with boracic acid, similar com- 

 pounds are formed. In heating in the same manner 6 parts of silicic acid 

 and 13 parts of cyanide of potassium, a brittle porous mass s obtained, 

 which after washing affords ammonia by fusion with caustic potash. 



Formation of Ammonia.— M. Ruset (Jour, de Phar. et de Chim. II, 

 *•>/) has shown that a mixture of hydrogen gas and nitric oxide, pass- 

 ed through a tube containing heated peroxide of iron, gives rise to the 

 formation of ammonia ; in the space of half an hour, he obtained suf- 

 ficient to saturate an ounce of hydrochloric acid. The oxide of iron 

 exercises simply a catalytic action, and is not reduced so long as there 

 is no excess of hydrogen. 



Calomel. — It is known that the medicinal action of calomel is more 

 ^ergetic in proportion as the powder is finer. M. Soubeiran (Jour. 

 fa pr. Chem. XXVI, 414) effects this pulverization by means of a bel- 

 lows, which drives a current of air through a large glass tube, contain- 

 1!1 g the calomel heated so as to volatilize it. The current of air con- 

 denses the vapors, and carries them in the form of a very fine powder 

 * m ° an elongation of the tube connected with a recipient of water. 

 * Righini (same journal) has shown that when the air is replaced by 

 e va P°r of water, a small quantity of corrosive sublimate is formed. 

 4 New Method of Precipitating the Sulphurets of Metals.— M. 

 Himley (Ann. der Chim. und Pharm. XLII, 347) has made known a 

 Dew method of precipitating the metallic sulphurets without the use of 

 ^phuretted hydrogen. It consists in mixing the metallic solution with 

 1 e hyposulphite of soda ; this salt in most cases produces no precipi- 

 ^ te ' but if hydrochloric acid is added, the metallic sulphuret is imme- 

 latel y precipitated. All the metals precipitated by sulphuretted hydro- 

 gen ' are also precipitated by this method. It is M. Himley's intention 

 examine into the accuracy of this method by new experiments. 



determination of the Copper in a Solution of a Binoxide Salt.—H. 



rf v °l (Ann. de Chim. et de Phys. V, 381) has made an important mod- 



1 ca tion to M. Fuch's method for determining the copper contained in 



a s °lution of a binoxide salt, by the quantity of copper required to re- 



Uce u t0 ^e state of a protoxide salt. He places the solution of the 



1 lr * a vial, adds ammonia until the liquid becomes of a transparent 



oI ' **TOj No. l.-April-June, 1844. 25 



% 



