Cheiiiical Science. 177 



of lime did the same, and became black. Hydrate of magnesia, 

 dried in the air, also absorbed the gas. The cyanides of lime 

 and strontian contain 1 atom of oxygen, and 2 atoms of 

 cyanogen. 



A combination of oxide of mercury and cyanide of mercury 

 also exists ; it is probably formed of 



3 atoms of cyanide of mercury 1.737 



2 atoms of peroxide 992 



Ann. de Chim. xvii., p. 37. 



7. On a New Salifiable Base, by Dr. G. Brugnatelli.— Dr. 

 Brugnatelii, in pursuing his experiments on uric acid, has dis- 

 covered a new salifiable base. This substance, with his experi- 

 ments on it, have been described in a memoir read to the Royal 

 Institute at Milan, on January 4, 1821. An abridged account 

 of it is inserted in the Glornale de Fisica, t. iii., p. 464. 



The new substance is produced by the action of liquid acids 

 on uric acid. Those that have been used are the sulphuric, nitric, 

 muriatic, and acetic ; and the uric acid may be either that of cal- 

 culi or of birds or snakes. It is formed by adding concentrated 

 sulphuric acid, for instance, in small quantities at a time, to 

 uric acid, until a thick paste is formed ; it will occasion swelling 

 the liberation of gas, and a particular odour. When these 

 signs have ceased, add water, the mass will become very white ; 

 and on standing, will separate into two parts. The solid por- 

 tion is a neutral combination of the nev/ base with sulphuric 

 acid. The fluid is a portion of this compound dissolved in the 

 excess of acid, and containing impurities. The sulphate is but 

 little soluble in water, but the solution, decomposed by alkaluie 

 subcarbouates, yields a white light flocculent substance, which 

 is the base in question. Muriatic acid is, perhaps, better than 

 tlie sulphuric for the preparation of this substance, inasmuch as 

 the muriate is more soluble. Acetic acid requires boiling to 

 form it. and nitric acid produces it among other products at the 

 time of its violent action. 



The flocculent matter collected on a filter, appears like gela- 

 tine ; in drying it contracts and splits, and when pulverized has 

 the appearance of an earth. It has no taste or smell. It is 

 slightly soluble in water, alcohol, acids, and alkalies. The im- 

 pure acid solution is eminently distinguished by its property of 

 giving a very fine azure precipitate with triple prussiate of 

 potassa, and which may readily be distinguished, after a few 

 experiments, from that caused by iron. It may, perhaps, be ap- 

 plicable to dyeing or painting. The neutral combination of the 

 substance with acids does not give the blue precipitate, it re- 

 quires for this purpose excess of acid. 



Tl>is sub.stance combines with various simple bodies. With 

 iodine it forms a compound at common temperatures, of a 

 Vol. XII. N 



