BULLETIN OF THE BUSSEY INSTITUTION. 403 
by distilling a percolate from the coal with acetic acid, both before and 
after the action of amalgamated zinc, and testing the distillates with 
iodo-zine starch; and by digesting a percolate with metallic aluminum 
in presence of caustic soda, and distilling the mixture to obtain any 
ammonia that might have been formed. Negative results were ob- 
tained in each instance, although it appeared, from the results of other 
work that was being done at the same time, that the methods and the 
reagents employed were excellent and delicate. 
I have to thank my assistant, Mr. D. 8S. Lewis, for his careful at- 
tention to the details of this investigation. 
