Intelligence and Miscellaneous Articles, 79 



upon syrup of violets j potash did not evolve any ammonia from 

 it, and on being evaporated to dryness a considerable quantity 

 of cyanuret of mercury remained undecomposed. The ochre- 

 ous matter remaining on the filter was treated with water aci- 

 dulated with muriatic acid ; the peroxide of iron having been dissolved 

 in this manner, there remained an insoluble matter of a dark greenish 

 blue colour, which was a mixture of prussian blue and very finely di- 

 vided mercury. It results from this experiment, that when iron is 

 left in contact with a solution of cyanuret of mercury, water is de- 

 composed j its oxygen combines with the iron, and its hydrogen with 

 the cyanogen, while the mercury is reduced to the metallic state. 

 This action, however, as Scheele has remarked, is slow, but it is in- 

 stantaneous if a little sulphuric acid be added. 



Although an earthen vessel is, in the opinion of M. Guibourt, pre- 

 ferable to an iron one in preparing the cyanuret of mercury, yet it 

 may be made in the latter without any great inconvenience, on 

 account of the crust of oxide with which iron vessels are commonly 

 covered when used in laboratories. — Journal de Chimie Me'dicatey 

 April 1835. 



SULPHURET OF ZINC AND IRON. 



M. Bouis of Perpignan has analysed a double sulphuret of zinc and 

 iron which occurs at Cabrera on the right of the road from Aries k 

 Prats to Mello. This sulphuret has a brown colour ; its fresh frac- 

 ture is scaly, with small interlacing laminae of a brownish grey me- 

 tallic lustre. Its specific gravity varied from 3*2 to 3*6 when cellular, 

 and was 3*85 when compact. Its powder was brown, effervesced 

 slightly with an hepatic odour when put into diluted sulphuric acid. 

 It yielded by analysis : 



Sulphuret of zinc 6700 



Sulphuret of iron 19*86 



Oxide of zinc 0*16 



Peroxide of iron 4*00 



Silica 4-00 



Water and carbonic acid . . 4*20 



Loss 0*78 



100-00 

 The pure mineral is therefore composed of 



3 atoms of sulphuret of zinc 77045 



1 atom of sulphuret of iron 22955 



lOO'OOO 



Ibid. 



Scientific Boohs nearly ready for Publication. 

 The Second Edition of the First and Second Reports of the British 

 Association for the Advancement of Science. 

 Transactions of the Linnaean Society, Vol. XVII. Part ii. 



