180 RECAPITULATION 



CHAPTER Vin. 



Of manures. 



Irrigation, or manuring by running water. 



Vegetable manures, their nature* Not so energetic 

 in action as some fertilizers, but very beneficial to the 

 soil. 



Green crops for ploughing under These lighten 

 and mellow the soil, add organic matter to it drawn 

 from the air, and bring up mineral substances from 

 the subsoil. 



Straw. Seaweed: valuable composition of its ash; 

 should be applied in compost, or ploughed in fresh. 

 Rape dust, how used. 



Animal manures. 



Flesh, blood, hair, horns, bones, etc. All quite rich, 

 containing much nitrogen, and very valuable. 



The animal contains no silica. 



Bones are best applied in the form of dust, or dis- 

 solved by sulphuric acid. 



Phosphates of the bones, are important to replace 

 those carried away by the grain crops. 



CHAPTER IX. 



Animal manures {^continued). 



Manures of domestic animals. 



Importance of preserving both the solid and the 

 liquid parts of the manure; tanks are necessary, and 

 all other precautions, to prevent drainage, exposure, 

 and consequent loss of nitrogen. 



Manure of birds richest of all, having the solid and 

 the liquid parts together. Guano an instance of this 

 class, very rich in nitrogen and in phosphates. 



Fish, an important manure; contains much nitro- 



