BONES. 231 



with 20 tons of good stable manure at a cost of $55., and 

 the other with 1200 Ibs. of complete artificial manure at a 

 cost of $30. These quantities were equally divided between 

 6 acres, and the yield over the whole field averaged a little 

 over 1200 bushels per acre, with but little difference between 

 the different parts of the field; the difference being in favor 

 of the complete artificial manure which yielded roots of 

 large size. This result is what might be expected from the 

 solubility and consequent availability of the complete man- 

 ure, which was made up of superphosphate of lime, muriate 

 of potash, and sulphate of ammonia. 



DRIED BLOOD AND FLESH. The refuse of the large 

 slaughtering establishments and the meat canning factories, 

 furnishes a large amount of most valuable plant food which 

 was formerly wasted. This is however mostly used by the 

 manufacturers of fertilizers in the compounding of complete 

 manures, or in the enrichment of superphosphates of the 

 class known as ammoniated fertilizers. The rapid decom- 

 position of these preparations of blood and flesh, causes the 

 free production of ammonia, the loss of which is avoided 

 by its combination with the free sulphuric acid of the super- 

 phosphate and the formation of sulphate of ammonia. The 

 composition of this substance is given in the table at the 

 end of this chapter, along with that of the following waste 

 matters used for manures. 



BONES have been used for manure for farm crops for 

 many centuries. It is supposed that their value in this di- 

 rection was first discovered by the extraordinary fertility 

 of ancient battle fields which w r ere brought under cultiva- 

 tion, and in which the decaying bones formed a considera- 

 ble element in the soil. Some years ago ground bones were 

 the only artificial manure used to help out the always in- 

 adequate farm manure, and it was the beneficial results 

 from this fertilizer w r hich started the investigations w T hich 

 resulted in the discovery of the value and method of mak- 

 ing superphosphate of lime and ended in the present enor- 

 mous manufacture and use of what are called artificial fer- 

 tilizers. 



