]80 ACCOUNT OF A MINERAL SUBSTANCE. 



other fubftances, which are now confidered as fimple, primi- 

 tive, and diftinct bodies, will be found to be compounds. Yet 

 I only entertain and ftate this opinion as a probability ; for, 

 until an advanced ftate of chemical knowledge fhall enable us 

 to compofe, or at leaft to decompofe, thefe bodies, eacn mult 

 be clafled and denominated as a fubftance fui generis. Conii- 

 dering, therefore, that the metal which has been examined is 

 fo very different from thofe hitherto dilcovered, it appeared 

 proper that it fliould be diftinguimed by a peculiar name; and, 

 having confulted with feveral of the eminent and ingenious 

 chemifts of this country, I have been induced to give it the 

 name of Columbium. 



POSTSCRIPT. 



It appears proper to mention fome unfuccefsful attempts 

 which I have lately made to reduce the white oxide. 

 Rrilu&ion. The Fifty grains were put into a crucible coated with charcoal; 

 w ^on^black- anc ^ De ' n g covered with the fame, the crucible was clofelv 

 ened by the luted, and was expofed to a ftrong heat, in a fmall wind fiir- 

 ftrong heat with nace during about one hour and an half. When the crucible 



caaicoal. ° 



was broken, the oxide was found in a pulverulent ftate ; and, 

 from white, was become perfectly black. 

 The phofphuret. In order to form a phofphuret, fome phofphoric acid was 

 poured upon a portion of the white oxide ; and, being eva- 

 porated to drynefs, the whole was put into a crucible coated 

 with charcoal^ as above defcribed. The crucible was then 

 placed in a forge belonging to Mr. Chenevix, and a ilrong 

 heat was kept up for half an hour. 



The inclofed matter was fpongy, and of a dark brown; it in 

 fome meafure refembled phofphuret of titanium. 



After this we wiflied to try the effect of a ft ill greater heat ; 

 but in this experiment the crucible was melted. 



The above experiments fhew, that the white oxide, like 

 feveral other metallic fubftances, may be deoxidated to a cer- 

 tain degree, without much difficulty, but that the complete re- 

 duction of it is ftill far from being eafily effected. 



V. On 



