[ 18 ] 



VII. On Metallic Titanium. By W. H. Wollaston, M.D. 



V.P.R.S* 

 T^HE evidence that we yet possess of the reduction of ti- 

 -*• tanium to its metallic state, is not altogether satisfactory ; 

 for even Laugier (who has described a valuable series of ex- 

 periments made upon it in ISl^, and who had the advantage 

 of all the previous knowledge acquired by the labours of Vau- 

 quelin and Hecht in 1796, of Lovvitz in 1798, and of Lam- 

 padius in 1803) coidd only say that he thought himself justi- 

 fied in considering certain parts of his product which were of 

 a golden colour as really reduced ; adding in confirmation, 

 that Messrs. Vauquelin and Ha'uy, to whom he had shown 

 them, " appeared disposed to adopt his opinion f." 



As M. Laugier had not the means of confirming his opi- 

 nion by analysis, I may presume that an account of some ex- 

 periments which I have recently made upon this substance 

 will be acceptable to chemists in general ; and that in pro- 

 portion to the degree of doubt they may entertain, they will 

 feel interested to examine scrupulously the evidence 1 shall 

 adduce as to the metallic state of the subject of my experi- 

 ments. 



My attention has been directed by various friends, especially 

 by Professor Buckland, who gave me the subject of my ex- 

 periments, to certain very small cubes, having the lustre of 

 burnished copper, that occasionally are found in the slag of 

 the great iron-works at Merthyr Tydvil, in Wales, which, 

 from their hue, have by some persons been imagined to be 

 pyritical. Their colour, however, is not truly that of any sul- 

 phuret of iron that I have seen ; and though the form be 

 cubic, it is not the striated cube of common iron pyrites, which 

 so often passes into the pentagonal dodecahedron, but similar 

 to that of common salt ; for any marks, that are to be dis- 

 cerned on their surfaces, appear as indented squares instead 

 of striaj. 



Their hardness also is totally different from that of pyrites, 

 and is such as, when combined with the preceding characters, 

 marks a substance wholly unknown to mineralogists. By se- 

 lecting a sharp angle of one of these cubes, I found that I 

 could not only write upon the hardest steel, or upon crown 

 glass, but could even visibly scratch a polished surface of 

 agate or rock crystal. 



* From the Philosofrliical Transactions, Part I. for 182.3. 



f Je nic crois fondc a rcgarder cctte coiichc mamnielonnee commc la 



>ortion recllemciit rediiitc 



MM. Vauijuclin ct Haiiy m'ont paru disposes a ado|)tcr cctte opinion. 



AiDialrs dc Chimie, vol. Ixxxix. p. ^17. 



Havinir 



i:; 



