268 Process of Fulminating Powder, 6^c. 



of the mercury a heat above the softening point of glass was 

 necessary. 



So great was the avidity for oxygen of the metals thus ob- 

 tained, that to see their bright metallic white color, the eye must 

 follow closely after the movements of a file or burnisher employed 

 to expose a fresh surface. Metallic whiteness is soon succeeded 

 by a straw color, as in the case of steel filed at a high tempera- 

 ture. But the whole mass is soon reduced to the state of a pul- 

 verulent oxide. Of this the color is dark, in consequence of a re- 

 sinous coating resulting from reaction of the metal with the 

 naphtha necessarily employed to prevent the excess of atmos- 

 pheric oxygen. In consequence of this coating being insoluble 

 in water, but readily soluble in hydric-ether, oxidizement ensues 

 more readily in the last mentioned liquid than in water. 



The metals in question were all brittle, and much harder than 

 potassium or sodium. By the evolution of the mercury, they are 

 left in a form resembling, in some degree, that of metallic arsenic. 



Davy informs us that he employed only fifty or sixty grains of 

 mercury. Dr. Hare has employed a half a pound avoirdupois, 

 which is seventy times as great, and is under the impression that 

 with sixty grains it would not be possible to isolate a perceptible 

 quantity of calcium. Operating with much larger quantities of 

 amalgam, he has found no residue besides a stain upon the glass 

 of the tube employed to distill off the mercury. 



Art. X. — Process for a Fulniinatirig Poivder — for the Evolution 

 of Calcium and Galvanic Ignition of Gunpoivder ; by Dr. 

 Hake. 



An equivalent of quick lime, with an equivalent and a half of 

 bycyanide of Mercury, is subjected to a red heat in a porcelain 

 crucible enclosed within an air tight alembick of iron so as com- 

 pletely to exclude atmospheric air. The resulting residual mass 

 was found in two experiments, to have the weight which would 

 correspond with an equivalent of calcium, united to an equivalent 

 of Cyanogen. From the filtered solution of the compound, thus 

 produced, in acetic .acid, a precipitate was obtained by the addition 

 of nitrate of the protoxide of mercury. This precipitate when 

 well dried was found to constitute a powder capable of fulmin- 

 ating by percussion. 



