46S Scientific Intelligence. [Dec. 



both in muriatic and sulphuric acid, when concentrated and boiling. 

 It combines readily with the alkalies, both caustic and carbonated, 

 when boiled in an alkaline lev. With microcosmic salt before the 

 blow-pipe, it melts into a blue glass, with a shade of purple. 



" Mr. Ekeberg describes the oxide of tantalum as follows : — 

 ■ This oxide may be reduced into an infusible metallic substance, 

 having the grey colour of iron. The oxide is insoluble in acids, 

 particularly the nitric and muriatic. If an alkaline solution of 

 tantalum be poured into a greater excess of concentrated muriatic 

 acid, a small quantity of the oxide remains in solution in the acid, 

 but the greatest part is precipitated. To combine this oxide with an 

 alkali, it must be fused with several times its weight of fixed alkali. 

 Carbonic acid precipitates it from its alkaline solutions. Fused with 

 microcosmic salt, it eives a transparent and colourless glass/ 



" Ekeberg had received from a friend, who had visited England, 

 a small portion of Mr. Hatchett's columbic acid ; and when he was 

 informed of the result of Dr. Wollaston's experiments, he made a 

 careful examination of that acid. He found that it contained a 

 considerable proportion of tungstic acid. To this it owed its acid 

 properties, the ease with which it combined with alkalies, and the 

 blue colour which it communicated to microcosmic salt. He 

 ascertained that the other constituent of columbic acid possessed 

 the properties of oxide of tantalum. The substance then called 

 columbic acid was a mixture ojf tungstic acid and oxide of tantalum. 



" These observations of Mr. Ekeberg have gained still more 

 weight by the discovery of a new mineral by Mr. Gahn and myself 

 in the environs of Fahlun. It has a very close resemblance to the 

 columbite of Mr. Hatchett, and we have found that it consists of 

 tungstic acid combined with oxide of tantalum, oxide of iron, and 

 oxide of manganese. We shall publish hereafter our experiments 

 on this mineral and upou tantalum, which will be found conform- 

 able to the opinions of Ekeberg. From this statement, it is clear 

 that Hatchett participates with Ekeberg the discovery of tantalum, 

 in the same way as Foureroy and Vauquelin participate with Ten- 

 nant the honour of the discovery of osmium. (See Thomson's 

 Chemistry, 4th Edit. vol. i. p. 200.) I suppose you will not refuse 

 the same justice to the Swede Ekeberg that you have done to the 

 Englishman Tennant. 



" As to the name of the metal, I do not think that the claim of 

 the original discoverer is great- You do not, for example, say 

 menachan in place of titanium. Mr. Hatchett chose the name 

 columbiura from the place from which he supposed the specimen 

 came ; but this is not a good method of naming minerals. Besides, 

 in the present case the locality is doubtful. We are not sure that 

 the specimen came from America. The word tantalum has none of 

 these inconveniences ; and as it points out, besides, some of the 

 most striking properties of the mineral, I think that it ought to be 

 employed in preference. Perhaps the name tantalum (from th* 



