110 Wohler and Deville on the affinity of Titanium for Nitrogen. 



the action^ at a liigli temperature, of sodium on the double fluo- 

 ride of titanium and potassium in an atmosphere of hydrogen. 

 It is a dark gray powder, like iron reduced by hydrogen. The 

 substances hitherto obtained in reduction experiments, and de- 

 scribed as titanium, really consist of nitride of titanium. Of 

 the two constituents of the atmosphere, oxygen is that which 

 offers most resistance to the preparation of elements in their 

 pure form ; but in the case of titanium, it is nitrogen. A cru- 

 cible lined with charcoal, and filled with a mixture of titanic 

 acid and charcoal, is impermeable to the oxygen of the furnace, 

 while it is penetrated with ease by the nitrogen. 



Wohler and Deville mixed titanic acid and charcoal in the 

 proportion in which, by assimilation of nitrogen, they would 

 form the cubic titanium of the blast-furnaces, Ti C^ N + 3Ti^ N. 

 A small charcoal tray was filled with this mixture, and heated in 

 a tube of dense carbon*, externally protected from combustion, 

 to a temperature at which platinum melts ; at the same time a 

 stream of pure, dry nitrogen was passed through the tube. When 

 the temperature had reached a certain point, and the gas passed 

 through in a rapid stream, the tray became perceptibly more in- 

 candescent than the surrounding tube ; and the nitrogen was so 

 rapidly absorbed, that nothing but pure carbonic oxide issued 

 from the other end of the apparatus. The apparatus was then 

 allowed to cool, the passage of the gas being continued. The 

 contents of the tray were then found to be changed into a cry- 

 stalline substance of metallic lustre, which had all the chemical 

 and physical properties of the titanium of the blast-furnaces. 

 When this substance is heated in a lime-crucible to a tempera- 

 ture at which rhodium becomes liquid, it was found to be dimi- 

 nished in volume and covered with small octahedral crystals. 



It would seem from this experiment, that nitrogen in its free 

 state has such an affinity for titanium, that it can unite with it ; 

 at any rate if it comes in contact with it at a high temperature 

 at the moment of its formation. 



On heating a mixture of charcoal and titanic acid in a carbon 

 crucible to a high temperature, a large quantity of cubic tita- 

 nium was formed. It was also formed by the action of sodium 

 upon fluoride of titanium and potassium in a tube heated to red- 

 ness, through which nitrogen was passed. 



Another instance of this unexpected property of nitrogen has 

 been made known by Wohler and Devillef, who, in continuing 

 their investigation of boron, have found that this element also 

 possesses the property of directly combining with nitrogen. 



Amorphous boron they now prepare by an easy and expeditious 



* Phil. Mag. vol. xiii.p. 124. f Kosmos, Nov. 27, 1857. 



