V^VLUATION OF FERTILIZERS, ETC. 455 

 Crude Kieserite. 



[Of Randall Fertilizer Co., Boston, Mass. Sent on by C. P. Preston, Danvcrs, Mass ] 



Moislure at 100 C 28.12 



Magncj-ium oxitlo, 17.45 



Calcium oxide, 3.13 



Sulphuric acid, 36.87 



Insoluble mutter, 3.62 



The sample contained 48.6 per cent, of sulphate of mag- 

 nesia, from 7 to 8 per cent, of gypsum, and 2.23 per cent, 

 of chloride of magnesium ; it is consequently of fair quality. 

 The kieserite, as an absorber of ammonia, may profitably be 

 used in many instances as a substitute for gypsum. 



Nova Scotia Plaster (Gypsum). 



[Collected of R. T. Prentiss, Holyokc, Mass.] 



Pounds 

 per Hundred. 



Calcium oxide, . . . • . . , . . . . 32.17 



Magnesium oxide, 1.40 



Sulphuric acid, 44.00 



Insoluble matter, .70 



The sample contains 94.8 per cent, of gypsum, and is a 

 fair article. The customary market price in our vicinity is 

 $9 per ton. 



Onondaga Plaster (Gypsum). 



[Collected of Sheldon & Newcomb, Greenfield, Mass.] 



Pounds 

 per Huudred. 



Calcium oxide, 29.15 



Magnesium oxide, 3.89 



Sulphuric acid, 3182 



Insoluble matter, 9.25 



This article sells at |6 per ton ; its cost corresponds well 

 with its percentage of gypsum, — 67 to G8 per cent. 



Onondaga Plaster, 



[Collected of H. D. Fearing, Amherst, Mass.] 



Per cent. 



Moisture, 22.25 



Calcium oxide, 29.80 



Magnesium oxide, 4.32 



Sulphuric acid, 31.58 



Carbonic acid, 8.80 



Insoluble matter, 10.70 



This sample contains a considerable amount of carbonate 



