URANIUM. 13 



longed to the protoxide of lead, the remainder, 

 amounting to 0*0574, existed in the peroxide of 

 uranium. It follows from these data that the 

 peroxide of uranium is a compound of 



Uranium 100 



Oxygen 5-5765 



The mean of these two results gives us the con- 

 stituents of the peroxide as follows : 



Uranium 100 



Oxygen 5-56775 



Now, if the atomic weight of uranium be 26, 

 and if the peroxide be a compound of 1 atom 

 metal and 2 atoms oxygen, its constituents 

 would be 



Uranium 1 00 



Oxygen 7-6923 



The preceding experiments do not correspond 

 with this supposition. They agree more nearly 

 with the notion that the peroxide of uranium 

 contains 1 atom of oxygen: for on this sup- 

 position, its constituents would be 



1 atom uranium 26 or 100 



1J atom oxygen 1-5 - 5-76923 



27-5 



This somewhat surpasses the result obtained by 

 Arfwedson, but not very much. 



