336 



PKOCEEDINGS OF THE AMERICAN ACADEMY. 



SERIES B. 

 Distillation Method. 



entire test solution is as low as 0.01 mg., since the correction is only 

 four per cent of this quantity, which is well within the limit of accu- 

 racy of the method itself "With larger amounts than 0.01 mg. the cor- 

 rection for this acid is of course of even less account. 



Presence of Arseniates in the Urine. The compound in which arsenic 

 occurs in the urine has never to our knowledge been thoroughly inves- 

 tigated. To determine accurately the condition of such small amounts 

 as would ordinarily occur would be a matter of considerable difficulty- 

 Schmidt and Bredtschneider 21 claim to have found arsenic acid and 



31 



Moleschott's Untersuchungen, 6, 146 (1859). 



