The Purchase of Artificial Manures. 



Basic slag generally leaves little to be desired as regards 

 mechanical condicion, provided the grinding be fine enough 

 (80 per cent, through a No. 100 sieve should be the minimum 

 requirement). Superphosphate is sometimes almost as dry 

 and mealy as slag, but in other cases it is lumpy and sticky. 

 Samples of the latter character are of reduced value, and 

 should be avoided. 



Superphosphate is of varying degrees of quality, the usual 

 contents being 28 to 30 per cent, of soluble phosphate. 

 Basic slag also varies in quality, the usual contents being 

 35 to 40 per cent, of insoluble phosphate. 



Phosphatic manures are of special value in the manuring 

 of turnips, leguminous crops, hay and pasture. They are 

 of less importance for potatoes and mangolds, and least of 

 all for cereals. In the case of the last class of crops it 

 usually happens that the plants are able to satisfy their 

 requirements from the natural supplies in the soil, or from 

 residues of former applications. Whether, on any particular 

 farm, it will pay to apply a direct phosphatic dressing to a 

 corn crop can only be determined with certainty by means of 

 a simple field experiment. 



Nitrogenous-Phosphatic Manures. 



The most important of these is dissolved bones, though 

 bone meal, fish meal, etc., nave their value for certain 

 purposes. 



Dissolved bones lose in value through being damp and 

 lumpy ; they can, however, be bought as dry and almost as 

 fine as superphosphate. They usually contain 32 to 34 per 

 cent, of total phosphates (of which more than half should be 

 soluble), and fully 3 per cent, of nitrogen. Bone meal 

 should be very fine and free from grease. Any particles ^ 

 of an inch or upwards in size become available very slowly. 

 It should hold about 50 per cent, of phosphates and a per 

 cent, of nitrogen. 



Potash Manures. 



Genuine Kainit contains about 12J per cent, potash, 

 besides which it holds over 30 per cent, of common salt. 



