COLUMBIUM. 73 



The evidence which Berzelius has advanced in 

 support of this opinion is the statement by Hat- 

 chett, that when his powder was fused with phos- 

 phate of ammonia before the blow pipe in a pla- 

 tinum spoon, the globule, when cold, had a deep 

 blue colour, with a tinge of purple. Now, it is 

 well known that tungstic acid produces this ef- 

 fect when fused with phosphate of soda ; where- 

 as, columbic acid melts with that salt into a white 

 transparent globule. Berzelius found tungstic 

 acid in some specimens of columbite, which he 

 examined, from the neighbourhood of Fahlun, 

 and he was informed that Ekeberg had examined 

 the columbic acid of Hatchett, and had found it a 

 mixture of the oxides of columbium and tungsten. 



With respect to Mr. Hatchett's experiment, 

 it will be impossible to account for it, unless we 

 suppose that some tungstate of potash, which he 

 was obviously using, as appears from his pa- 

 per, had accidentally got into the platinum spoon 

 and produced the blue colour of the bead. That 

 the specimen in the British Museum, examined 

 by Mr. Hatchett, contained no tungsten is next 

 to certain, because Dr. Wollaston did not find 

 any in it ; and though he made a trial on pur- 

 pose at my request, when Professor Berzelius in- 

 formed me of his opinion, he was still unsuccess- 

 ful. I conceive, therefore, that it is but an act 

 of justice to Mr. Hatchett to retain the name 

 columbhim, which he originally imposed. 



