Manures and Fertilizers. 31 



Bone Meal and Steamed Bone Flour each contains a small 

 variable amount of nitrogen, but this is not in a very active 

 condition, and so far as immediate results are concerned both 

 should be considered solely for their value as phosphatic 

 manures. They should be bought upon analysis ; the former 

 should contain about 45 per cent, and the latter from 55 to 60 

 per cent, of calcium phosphate, of which rather less than one- 

 half is soluble. Bones act best on light, free-working soils; 

 on heavy soils they are very slow. Bone manures may be 

 considered as the best phosphatic fertilizers for soils which are 

 too poor in lime to be suitable for superphosphate and too dry 

 for basic slag. 



Use 4 to 8 cwts. per acre, or li to 3 ozs. per square yard. 



Dissolved Bones is the trade name for a substance obtained 

 by the treatment of bones with sulphuric acid to make the 

 phosphates soluble. \ It is a rather damp and sticky material and 

 should be mixed before use with sifted dry soil or something 

 similar to make it handle better. It usually contains about 

 20 per cent, soluble phosphates and 2 per cent, nitrogen. It is 

 the best phosphatic manure for use on chalky ground, 



Use 4 to 8 cwts. per acre, or li to 3 ozs. per square yard. 



POTASSIC FERTILIZERS. 



Sulphate of Potash is one of several potassic salts obtained 

 from the Stassfurt mines, in northern Germany. All of these 

 salts are white, grey, or pink gritty powders which dissolve 

 readily. Sulphate of potash contains about 50 per cent, pure 

 potash. It mixes well with other fertilizers. It is the best for 

 use on heavy soils and under glass, and should always be used 

 in preference to the muriate where quality of produce is of 

 importance. 



Like all the potash salts the sulphate is most effective when 

 applied in autumn, but may be very usefully applied in spring, 

 at the rate of 1 to 2 cwts. per acre, or \ to 1 oz. per square 

 yard, using the smaller quantity on clay soils. 



Muriate of Potash contains about 45 per cent, pure potash. 

 With the exceptions mentioned above, it is used on all crops in 

 a similar way and in the same quantities as the sulphate. 



