the Carinthian Molybdate of Lead. 301 
prussiate of pot-ash, and obtained a quantity of Prussian 
blue. 
§ VIII. Molybdate of Lead, with black Flux. 
A 
One hundred grains of the ore were mixed with four times 
the weight of black flux. The mixture was then put into a 
crucible with a piece of charcoal over it ; a cover was fitted to 
the crucible, and it was placed in a furnace in which a strong 
heat was kept up during an hour. When the crucible was 
cold and was broken, there did not appear any reguline but- 
ton, but shining metallic particles were dispersed throughout 
the mass. 
It was then reduced to powder, and the largest particles 
were separated by washing, were dried upon paper, and 
weighed 31 grains ; upon examination they proved to be lead 
in the metallic state. 
Other particles were separated by a magnet, and the re- 
mainder consisted of a black powder.* 
A. Diluted nitric acid was poured on this black powder 
and dissolved it, excepting a small residuum, which consisted 
of siliceous earth with a little charcoal. 
1. The solution was diluted with distilled water and fil- 
trated. % 
2. I then first separated a quantity of lead by sulphuric 
• Scheele could not reduce molybdic acid by black flux. Scheele’s Essays, 
p. 238. — Several chemists however assert, that they have obtained a regulus of molyb- 
dsena, particularly Mr. Hielm, m Journ. de Physique, 1789, p. 372. — And Mr. 
Ruprecht, Journ. de Physique, 1790, p. 231. — But Mr. Islm ann did not suc- 
ceed. Journ. de Physique, 1788, p. 296. 
