COMMERCIAL FERTILIZERS. 



223 



I take the liberty to call the attention of all parties interested 

 to my previous discussion on the respective merits of the 

 various brands in our agricultural industry now offered for 

 sale. It is to be hoj)ed that the most important standard 

 brands of potassium chlorides and sulphates may henceforth 

 be had for a course of years, to permit a thorough experi- 

 mental inquiry into their special fitness, in our climate, for 

 different crops and upon different kinds of soil. 



Gypsum. 

 I. 



(Sent by Mr. T. D. Thatcher, Springfield, Mass.) 

 A. 



Sample B contains from six to seven per cent of its lime 

 in form of carbonate of lime (from 10.5 to 12 per cent). 



Gypsum (Nova Scotia). 



II. 



(Mr. P. Holden, Worcester, Mass.) 



