230 Encyclopaedia of Gardening 



manures. It was known that bones nourished crops, but that their 

 action was slow. Various plans were tried to bring the bones into 

 a quicker-acting state, amongst them that of treating with sulphuric 

 acid. This proved to be successful, and the product was put on 

 the market under the name of superphosphate of lime. Bone flour, 

 bone meal, and mineral superphosphate are other forms of prepared 

 bone. The following are the percentages of phosphoric acid in four 

 different fertilisers which yield that ingredient: 



basic slag 

 bone flour 

 bone meal 



phosphate of potash . 

 superphosphate 



38 



58 



45 (also yields ammonia) 



37 (also yields potash) 



28 



Basic slag, a by-product of the ironworks, is the most economical 

 form of phosphoric-acid fertiliser for soils which lack lime, while 

 superphosphate is the best for soils containing lime. Mineral super- 

 phosphate at the rate of 7 Ib. per square rod is a valuable fertiliser for 

 fruit trees and pod-bearing crops. It may be applied in February, 

 but should not be dusted over young growing crops. Potash is 

 also important. This is yielded by five different chemical manures 

 as follows:- 



sulphate of potash . 90 per cent. 



nitrate of potash . 83 ,, ,, (also contains nitrogen) 



muriate of potash . 80 ,, 



phosphate of potash. 48 ,, (also contains phosphoric acid) 



kainit . . 20 ,, ,, 



Nitrate of potash as also yielding nitrogen, and phosphate of potash 

 as also yielding phosphoric acid, are particularly valuable, but their 

 cost is very high, Kainit is good as a winter application turned 

 well under at the rate of 14 Ib. per square rod. Sulphate of potash 

 is excellent, and may be used at the rate of 4 Ib. per square rod ; or 

 3 Ib. may be used with 4 Ib. of superphosphate, the two being mixed 

 and applied about midwinter. The nitrogenous fertilisers are 

 valuable according to the quantity of ammonia which they yield. 

 The following is a table of kinds and quantities : 



sulphate of ammonia . 24 per cent. 



nitrate of soda . . 18 ,, 



nitrate of potash . . I5f (also contains potash) 



nitrolim , . .18,,,, 



The last is a modern fertiliser, the chemical name of which is calcium 

 cyanamide. It contains 20 to 30 per cent, of free lime, and is a 

 valuable manure for limeless soils. It could be used as a top dress- 

 ing for weakly crops in the same way as sulphate of ammonia and 

 nitrate of soda. It is wasteful to dig these into vacant ground in 

 winter. Shoddy, a waste from the wool factories, yields ammonia, 

 and is used by Hop growers. Hoof parings yield phosphoric acid. 

 Road scrapings are good for stiff soil. 



Liquid manure. Plants coining into flower, vegetables into pod, 

 and trees into fruit are benefited by liquid manure, whether in the 



