144 M. Boussingaulfs Analysis of a New Mineral. 



Oxide of lead, 

 Oxide of molybdenum, 

 Carbonic acid, 

 Hydrochloric acid. 

 Phosphoric acid, , 

 Chromic acid, 

 Oxide of iron, 

 Alumina, 

 Silica, 



73.8 

 10.0 

 2.9 

 1.3 

 1.3 

 1.2 

 1.7 

 2.2 

 3.7 



98.1 



We must necessarily suppose that, of the oxide of lead, 

 14.6 are combined with Carbonic acid ; 



5.3 Hydrochloric acid ; 



4.1 Phosphoric acid ; 



2.4 Chromic acid. 



26.4 

 Which leaves 47.4 in combination with the molybdic acid. 



In the neutral molybdate of the oxide of lead (P. b M o) 10 

 of molybdic acid will take up 15.2 of the oxide of lead. But 

 here the 10 grains of acid are united with almost three limes 

 that quantity of base. The mineral under consideration, there- 

 fore, seems to be a new molybdate of the oxide of lead, with three 

 times the quantity of oxide assigned by Hatchett to the neutral 

 salt. In the molybdate of lead of Pamplona, the oxygen of the 

 acid is almost exactly equal to that of the base ; it is, therefore, a 

 molyhas triplumbicus, and is expressed by the formula P b^ Mo. 

 We may, therefore, consider the mineral of Pamplona as con- 

 sisting of: 



Molybdate of oxide of lead (Pb ' 

 Carbonate of ditto, 

 Hydrochlorate of ditto. 

 Phosphate, 

 Chromate, 



Mo), 



Matrix, 



Uncombined oxide of lead, 



56.7 

 17.5 

 6.6 

 5.4 

 3.6 

 7.6 

 0.7 



98.1 



