284 ANNUAL OF SCIENTIFIC DISCOVERY. 



Carbon unites with tungsten with great facility. The presence or carbon 

 was determined in a few grains of the metal that had been melted in char- 

 coal ; it causes the metal to become brittle. Boiling water, distilled water, 

 or ordinary water, do not attack it even at the end of many months ; all that 

 can be remarked is, that the metal is slightly tarnished at the surface, but there 

 are no traces of the blue oxide formed. With dilute solutions of the alkalies, 

 the metal, instead of tarnishing, remains quite bright ; but in time there is 

 observed a small quantity of tungsten in solution. This action, so slow 

 under these conditions, becomes rapid enough if a concentrated and boiling 

 solution of potash be employed. Nitric acid heated changes this metal into 

 tungstic acid ; this action is not terminated until after some days, whilst it 

 is accomplished immediately with aqua-regia. Sulphuric and hydrochloric 

 acids attack it but slowly; nevertheless it is attacked, for the blue color of 

 the liquid soon become-s manifest. 



CHEMICAL CHARACTER OF TUNGSTEN. 



More recent researches of M. Kiche, superintendent of the Chemical 

 department of the Faculty of Sciences at Paris, establish the position of 

 tungsten in the series of simple bodies. According to him it is a metalloid 

 rather than a metal ; and he concludes that although dilfering in some charac- 

 teristics from boron and silicon, it should be arranged along side of these metal- 

 loids. 



INTERESTING RESEARCHES ON BORON. 



MM. Wohler and Deville have recently published the results of some 

 interesting researches on Boron, from which it appears that this substance 

 can exist in three states, exactly corresponding to those of carbon the amor- 

 phous, the graphitic, and the crystallized state. The preparation of crystal- 

 lized boron is as follows : eighty grammes of aluminum in thick pieces are 

 fused in a crucible of carbon with one hundred grammes of fused and pulver- 

 ized boric acid. The carbon crucible is placed in one of graphite, the inter- 

 stices being filled up, and the whole heated in a wind furnace to the temper- 

 ature at which nickel melts, for five hours. The mass is then left to cool, 

 and, on breaking the crucible, two distinct strata come to view, one consisting 

 of vitrified boric acid containing some alumina ; and the other of aluminum 

 in a metallic state, mixed up with crystals of boron. To separate the latter, 

 this metallic mass is treated with boiling caustic soda to dissolve the metal ; 

 then Avith boiling hydrochloric acid to dissolve the iron which may have been 

 separated from the plumbago of the crucible ; and lastly, with a mixture of 

 nitric and hydrofluoric acid, to dissolve the silicum left by the soda. After 

 this, the boron will be obtained crystallized in complicated aggregations of 

 numerous small crystals the form of which has riot yet been determined. 

 These crystals are sometimes garnet-red, and sometimes honey-yellow ; the 

 color however does not appear to be essential, and may arise from slight im- 

 purities. The crystals have a lustre and refractive power like that of the 

 diamond. They scratch corundum with the greatest ease, and appear to be 



