288 
Mr. Hatchett's Analysis of 
and communicated to the salt a green colour, more or less 
deep according to the quantity employed. 
They completely dissolved in distilled water, when heated. 
Prussiate of pot-ash with this solution produced a reddish- 
brown precipitate, not very dark. 
When some drops of muriatic acid were mixed with the so- 
lution of these crystals in water, and a small piece of tin was 
added, the liquor became of a deep blue. 
The solution of muriate of tin poured on the crystals pro- 
duced the same effect. 
Mr. Klaproth from these experiments concludes, that the 
crystals are the acidulous molybdate of pot-ash, especially as 
the crystals obtained from the filtrated solution of the molyb- 
dsena of Altenberg, detonated with nitre, and saturated with 
nitric acid, have the same properties. 
As in the above experiment the ore did not appear to have 
been completely decomposed, Mr. Klaproth mixed two 
drachms of the purified ore with ten of carbonate of pot-ash, 
melted the whole in a crucible, and reduced it to powder, and 
dissolved it in water. 
The solution was filtrated, partially saturated with muriatic 
acid, and heated. A white precipitate fell, resembling curdled 
milk, which consisted of molybdic acid, and a still larger 
quantity of oxyde of lead. When dissolved in muriatic acid, 
the lead was precipitated in the state of muriate of lead. 
This precipitate being separated by a filter from the alka- 
line solution partially saturated with muriatic acid, the solu- 
tion was then completely saturated with the same acid, and 
again became slightly turbid, and deposited a white precipi- 
tate, which resembled starch in cold water. This precipitate. 
