398 ZINC, CADMIUM, LEAD, &c. 



this experiment deutoxide of lead is composed 

 of 



Protoxide of lead 9-545 or 14 

 Oxygen . 0-290 - 0-43 



T^ foUwing.experiment, which I made with 

 great care, will show that the true composition 

 of deutoxide of lead is 14 protoxide 4- 0-5 oxy- 

 gen. 29 grains of deutoxide of lead were di- 

 gested in dilute, but pure nitric acid, till all ac- 

 tion was at an end ; the whole was then thrown 

 on a double filter, and the peroxide of lead 

 remaining undissolved was well washed and 

 thoroughly dried in a temperature of nearly 500 

 it weighed 15 grains. Hence it follows, that 

 the protoxide dissolved by the acid weighed 14 

 grains. Thus, 29 grains of deutoxide of lead 

 were resolved into 



Protoxide of lead . . 14 

 Peroxide of lead . . 15 



29 



But it will be shown immediately that 15 repre- 

 sents the atomic weight of peroxide, and that it 

 is a compound of 1 atom lead and 2 atoms oxy- 

 gen. Protoxide of lead is a compound of 1 atom 

 lead and 1 atom oxygen : hence it follows, that 

 29 deutoxide of lead are composed of 



2 atoms lead =26 or 1 atom lead 13 



3 atoms oxgen = 3 - ] atom oxygen 1*5 



29 14-5 



