408 Tungsten and Tellurium, 



dissolved in ammonia, the black powder again appeared, and 

 so on, as under 3. Part III. 



3. The solution 1, diluted largely with water, deposited an 

 abundant white precipitate, which was very heavy and rapidly 

 subsided. 



4. Alcohol and ammonia, respectively produced the same 

 effect, only more decidedly. 



5. This precipitate, evidently an oxyd of a metal, being col- 

 lected on a filter and dried, exhibited the following properties. 



6. Heated by the blow-pipe on charcoal, it was instantly vo- 

 latilized in part, and in part decomposed, with an almost ex- 

 plosive effervescence ; numerous ignited globules of metal 

 appeared on the charcoal, and burned with an abundant flame 

 of a delicate blue colour, edged occasionally with green. 



7. In many trials, these results always occurred, and some- 

 times a peculiar odour was perceived, at first thought to be 

 owing to arsenic, but it was incomparably feebler, and some- 

 what resembled that of radishes.* 



8. Zinc, iron, and tin, plunged into separate portions of the 

 nitro-muriatic solution, precipitated abundantly a black floc- 

 culent substance. 



'9. On charcoal before the blow-pipe, this substance was 

 very combustible, with a blue flame, and was completely dis- 

 sipated in the form of white oxyd, with the above smell. 



10. Some of it was obtained on the charcoal in metallic 

 globules ; it was a brittle metal, white, with a tinge of red, and 

 foliated, but not so distinctly as bismuth and antimony. 



1 1 . The filters on which the white oxyd had been deposited, 

 burned almost with explosion, nearly as rapidly as if they had 

 been soaked with nitrate of potash, or of ammonia, and the 

 characteristic blue flame appeared while the burning lasted. 



* This was most remarkably perceived on one occasion, where, under the idea 

 that possibly chrome might exist in the ores, they had been intensely heated in a 

 forge along with pearl ashes. The mass, when lixiviated, gave only a greenish 

 solution, becoming colourless by nitric acid, and again greenish by an alkali ; this 

 was supposed to be owing to iron and manganese. No metal was obtained, except 

 a few minute globules of attractable iron, but the laboratory was filled with white 

 fumes, having the peculiar odour alluded to. 



