16 History of physical Science from [July, 



"When the solution is evaporated, .the salt crystallizes in very 

 small prisms. Its capacity for saturating the acids is greater 

 than that of magnesia itself. 



These experiments have been repeated and confirmed by 

 M. Vauquelin. He found further, that it unites with sulphur, 

 and forms a yellow-coloured sulphuret, and that it contains 43*5 

 percent, of its weight of oxygen. From this analysis it is likely 

 that the weight of its atom will be about 2-25. 



Sir H. Davy has not only obtained the new alkali, but has 

 succeeded in reducing it to the metallic state. The metallic 

 basis, to which the name of lithium will of course be given, 

 bears a strong resemblance to the other alkaline metals, espe- 

 cially tc sodium ; to which it seems to be the most nearly allied. 

 — (See Annals of Philosophy, xi. 291, 373 ; and Ann. de Chim. 

 etdePhys.vii. 199.) 



2. Influence of the Metals on the Production of Potassium with 

 Charcoal. — M. Vauquelin, after roasting a portion of sulphuret 

 of antimony in order to deprive it of its sulphur, fused it in a 

 crucible with its own weight of tartar. The mass of metal 

 obtained had a greyish white colour, without lustre, and a gra- 

 nular texture. When put into water, an effervescence took 

 place, hydrogen gas was evolved, and the water was found to 

 contain a solution of potash; two grammes of this metal evolved 

 30 cubic centimetres of hydrogen gas, and 3-j^ grammes evolved 

 47 cubic centimetres. Hence M. Vauquelin concludes that the 

 antimony was alloyed with the 20th of its weight of potassium. 

 When this metal was exposed to the air, it became moist on the 

 surface, and the potassium was converted into potash ; but in 

 naphtha it was kept for 24 hours without any change. Bismuth, 

 being fused with tartar, formed a similar alloy. When the 

 experiment was tried with the oxide of lead, a button of a grey 

 colour was obtained, fibrous and brittle, affecting the tongue with 

 an alkaline taste, and restoring the colour of litmus reddened by 

 an acid ; but not effervescing in water. 



From these facts, Vauquelin concludes that in all probability 

 other metals, which are reduced by means of alkaline fluxes, 

 contain greater or smaller quantities of potassium, which modify 

 their properties, and which are dissipated Avhen the metals are 

 refined or exposed to the air. — (Ann. de Chim. et de Phys. 

 vii. 32.) 



3. Metallic Sulphurets. — M. Frere de Montizon is of opinion 

 that the metallic sulphurets are composed of determinate volumes 

 of sulphur and metal united together. The following table 

 exhibits the evidence upon which this opinion is founded. 



