8 N. H. AGR. EXPERIMENT STATION [Bulletin 219 



shown in heavy black type. The names of the manufact- 

 urers are arranged alphabetically and under the manufact- 

 urer the different brands are arranged alphabetically or 

 numerically by formula. 



Assistance in the analytical work has been rendered by 

 M. H. Voyagis and W. A. Westgate. 



