Experiment Station Report. 101 



The kieserit, on account of a o;reater solubility iu water, 

 exceeds in efficiency tiie sulphate of lime or gypsum, as an 

 absorber of ammonia, in manure cellars, in stables, and upon 

 the compost heap. 



Its well-known beneficial influence on a speedy diffusion 

 of potash compounds throughout a deeper layer of soil, as 

 well as its reputed favorable action on leaf and stem growth, 

 are of sufficient importance to encourage experiments on the 

 part of farmers, and in particular of gardeners and fruit 

 growers, to test its influence. The prominence of the mag- 

 nesia among the mineral constituents of many of our grain 

 crops and fruits, leaves scarcely a doubt about its import- 

 ance in the vegetable economy of many of our cultivated 

 plants. 



Potash Magnesia Sulphate. 



(Collected of Bowker Fertilizer Co., Boston, Mass.) 



Per cent. 



Moisture, at 100° C, 4.90 



Calcium oxide, 1-15 



Magnesium oxide, 11.30 



Potassium oxide, 24.94 



Sodium oxide, 2.09 



Sulphuric acid, 46.99 



Insoluble matter, 0.54 



Valuation per two thousand pounds, $34.92. 



The above compound belongs to a series of salines which 

 some ten years ago, under the name of "German Potash 

 Salts," or " Stassfurt Salines," were introduced into our 

 agricultural industry for manurial purposes. 



Its peculiarity consists in the combination of a large 

 amount of potassium sulphate, from 46 to 47 per cent., with 

 a remarkable quantity of magnesium sulphate, from 33 to 34 

 per cent. 



The magnesium sulphate stands foremost among sub- 

 stances noted for their quality to counteract the well-known 

 great retentive power of most soils for potassa. 



This circumstance renders the potash-magnesia sulphate a 

 very valuable material for the cultivation of deep-rooting 

 plants, in case of an exhaustion of potassa in the subsoil. 



The potash-magnesia sulphate, as well as the " Douglass 

 Muriate of Potash," occupy a peculiar position among our 



