ON THE IDENTITY OF COLUMBIUM AND TANTALtJM. Q^ 



By favour of the Chev. de Souza I was also pevmitted, with 

 this view, to examine the specimen whicl) remained in his 

 possession, and had soon *he satisfaction of discovering- two 

 more fragments of the same mineral, and as I was in no one 

 instance deceived in my choice, by attending to the radia- 

 ting fibres, I am in liopes that this external character will 

 enable persons to distinguish this metal, in situations where 

 they have not an opportunity of deciding by chemical ex- 

 periment. 



iir. 



On the' Identity of Columhium and Tantalum. By Wil- 

 liam Hyde Wollaston, M. D, Sec. R. S*. 



ITHINa short time after the discovery of colnmbium Discovery of 

 by Mr. Hatchett, in ISOlf, a metallic substance was also tolumbium 

 discovered in Sweden by Mr. EckebergJ, dift'ering from ' 

 every metal then known to him ; and accordingly he described 

 the properties by which it might be distinguished from those 

 which it most nearly resembled. But although the Swedish 

 metal has retained the name of tantalum given to it by Mr. 

 Eckeberg, a reasonable degree of doubt has been enter- jj^^;^ identity 

 tained by chemists, whether these two authors had not in suspected, 

 fact described the name substance ; and it has been re- * 



gretted, that the discoverers themselves, who would have 

 been most able to remove the uncertainty, had not had op- 

 portunities of comparing their respective minerals, or the 

 products of their analyses. 



As T have lately obtained small specimens of the two Swe- Tantalum 



dish minerals, tantalite and yttro-tantalite, from which I compared with 



, . p ' • oxide cf co- 



could obtam tantalum, and was very desirous ot comparing lumbium. 



its properties with those of columbium, Mr. Hatchett very 



• rhilosophical Transactions for 1809, p. 246. 



f Phil. Trans, for l802 : or Journal, vol. II, p. 129, 176. 



I Vetemkaps Academiens Bandlingary 1802, p. 63. Jownal des Minss^ 

 Vol. XJI, p. 241?. or, Journal^ Vol. Ill, p. 251.J 



QblJginglf 



