COM mi i;< i \i. 111: hi i- 135 



each year by the oil mills of the South. and each year 

 more of it is being used for a fertilizer, especially in the 

 cotton States. Cottonseed-meal contains from 7 to 8 

 per cent of nitrogen, and, besides this valuable plant 

 food, contains 1 to 2 per cent of phosphoric acid, ami 1 h 

 to 3 per cent of- potash. When applied to the soil it 

 decays rapidly, and, besides the plant food it contain*, 

 it supplies the soil with much valuable organic matter 

 which goes to form humus. 



4. Bones of animals are mother source of nitrogen 

 for fertilizers. At the bone-yards of large cities, where 

 great numbers ol dead animals are taken, gad at the 

 slaughter-houses, where animals are prepared for mar- 

 ket, immense quantities of bones accumulate. A part 

 of these hones is ground up and sold as a fertilizer 

 under the name of raw ground bone. The raw bone 

 decays very slowly, and require* a long time bed 

 is fit for plant food. Bones are often steamed or 

 cooked for the purpose of making give or oil, and the 

 portion remaining after this process is sold as STEAMED 

 bone. It decays more rapidly in the soil, and is of 

 more value as a fertilizer. Raw ground hone contains 

 2 £ to 4J per cent of nitrogen, -teamed bone 1J 



ant Besides nitrogen, bones contain much phos- 

 phoric acid, and are classed as phosphatic fertilizers. 



V Dried blood is a product of the slaughter-house, 

 where quantities of it are dried and sold as a fertilizer. 

 Its value depends on its nitrogen, of which it contains 

 from 10 t«« \'! per Cent. It decays rapidlv in the soil, 

 and makes a \aluahle fcrtili If 



Tankage is another product of the slaughter- 



