of the University of Pennsylvania. 33 



[This test is not applicable to urine, nor is it 

 available in the presence of albumen or gelatin.] 



It is obvious that this reaction is useless to the 

 student as an isolated test, inasmuch as it responds 

 to two entirely distinct compounds, but its sim- 

 plicity and striking colorations give it very consid- 

 erable value when employed in corroboration of 

 other tests. 



