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duced in many instances I have no doubt, thougli from want of 

 sufficient experience or dexterity I have not been able to collect 

 their bases. The alkaline earths give the most marked results. 

 A little artificial carbonate of barytes was placed in a cavity scooped 

 in charcoal, and the unmixed flame directed on it with no ef- 

 fect but incandescence ; the heat was raised, and the powder 

 fused with violent effervescence, a yellowish green flame streamed 

 from it for a few seconds, and the liquid soaked into the char- 

 coal, or was volatilized in acrid ftunes. This constantly occurred, 

 and I found that the earth retained its acid till its fusion, at 

 which instant it must have partly become a hydrate, and partly 

 been reduced; the metal seems to be soluble in hydrogen, to judge 

 from the uniform tinge of the flame, and this is according to 

 the analogy of potassium, manganese, zinc and iron. Chloride of 

 barium was decomposed, even in the unmixed flame of hydro- 

 gen, as might have been expected from the strong aflinity be- 

 tween that gas and chlorine, but the base was volatilized. The 

 nitrate afforded the same results as the carbonate, and this whe- 

 ther they were gradually heated, or exposed at once to the most 

 intense action of the flame. Lastly, I used the earth itself, 

 obtained by decomposing pure crystals of the nitrate, which in 

 particular had been freed from iron bv ammonia. It cannot 

 be freed from this metal by crystallisation, and might easily 

 contain enough of it to afford deceptive appearances in these 

 experiments. (I had found that a mixture of the carbonates of 

 manganese and lime, when reduced in a powerful blast fur- 

 nace, gave a regulus of wliich i must have been calcium, and 

 by analogy iron and barium might be expected to possess ttie 

 same relation.) The earth then obtained was gray, without that 



