URANIUM. 35 



be a corroboration of my previous experiments. 

 The slight excess 0*43 (little more than one per 

 cent.) might be owing to the protoxide of ura- 

 nium not having been absolutely free from 

 foreign matter ; and the slight excess of weight 

 in Berzelius' numbers above the weight of the 

 salt employed, rather confirms this view of the 

 matter. I think it therefore certain, that the 

 true constitution of potash-muriate of uranium is 



1 atom sesquimuriate of uranium 34*9375 

 1 atom muriate of potash . 10-625 



45-5625 



But the salt formed by Berzelius contained an 

 excess of muriate of potash amounting nearly to 

 a fourth part. 



(3.) Peroxalate of uranium was also analyzed 

 by Berzelius. He does not inform us of the 

 method he employed to prepare it; but from 

 the result of his analysis it is evident that it con- 

 tained just twice as much peroxide of uranium 

 as my oxalate did. A quantity of this salt pre- 

 viously well dried was subjected to distillation in 

 a small retort. From 2*67 grammes of the salt 

 he obtained 0*353 gramme water, O5835 gramme 

 carbonic acid, and 1*7335 gramme uranium in 

 the metallic state, equivalent to 1-8668 peroxide 

 of uranium. Hence, the constituents of this salt 

 must have been 



C2 



