Chemical Science. 179 



appears to have been distributed 60 as to form oxide of tungsten 

 and soda, and, after the action of the chlorine, to have combined, 

 forming tungstic acid ; 873 parts of the compound, decomposed 

 by chlorine, gave 157 chloride of sodium = 89 soda; conse- 

 quently, 10.6 of soda per cent, in the compound. 



Sulphur heated with this body decomposed it entirely,' convert- 

 ing the tungsten into sulphuret. This was transformed by nitro- 

 muriatic acid into tungstic acid* 45 parts being obtained from 48.7 

 of the compound. These correspond to 86.2 per cent, of oxide of 

 tungsten in the compound* the residue t= 13.8 being, of course, 

 soda. Hence the compound contains, 



Calcul. 



Oxide of tungsten 4 atoms 87.81 - 86.2 

 Soda 1 „ 12.19 - 13.8 



100.00 100.0 



Attempts were made to produce this compound by directly com- 

 bining oxide of tungsten with soda ; when heated together me- 

 tallic tungsten and tungstate of soda were produced. When acid 

 tungstate of potash was heated in hydrogen, pure metallic tung- 

 sten was obtained. 



Chloride of Tungsten. — Sir H. Davy first formed chloride of 

 tungsten. M. Woliler shews the existence of three of these com- 

 pounds. When black oxide of tungsten is heated in chlorine in a 

 tube, combustion takes place, dense fumes are formed, which 

 ultimately produce a thick sublimate of white scales, resembling 

 in appearance native boracic acid; this is the perchloride of tung- 

 sten. In the air it gradually becomes tungstic and muriatic acids i 

 the change is more rapid in water. It is volatile at a low tempe* 

 rature, without fusing previously. Heated on platina foil, it is also 

 decomposed into muriatic and tungstic acid. As water converts 

 it thus into muriatic and tungstic acids, it must consist of, 



Chlorine 3 atoms - 35.9 



Tungsten 1 „ - 64.1 



100.0 

 166 grains of this compound dissolved in ammonia, evaporated and 

 heated, gave 130 grains of tungstic acid =; 62.65 of tungsten for 

 100 of chloride. 



When metallic tungsten is heated in chlorine, it takes fire and 

 burns into a chloride, with a minimum of chlorine. The com- 

 pound appears sometimes as delicate fine needles, of a deep-red 

 colour resembling wool, but more frequently as a fused deep-red 

 compact mass, with the brilliant fracture of cinnabar. When 

 heated, it fuses, boils, and yields a red vapour. In water it gra- 

 dually decomposes, producing muriatic acid and oxide of tungsten. 

 This compound dissolves in solution of pure potash, evolving hy- 

 drogen, forming chloride of potassium, and tungstate of potash. 



N 2 



