BONE MANURE. 119 



BONE MANURE. 



Agreeably to our promise, we now proceed to lay 

 before the readers of the Cuhivator the results of our 

 reading, coupled with our experience, in regard to bone 

 manure. 



The bones of domestic animals are found to contain 

 about equal portions of phosphate of lime and gelatine ; 

 those of young animals containing more of the latter, 

 and the bones of old animals more of the former. 

 The gelatine is highly nutritive to plants, and phos- 

 phate of lime enters largely into the structure of many 

 species. To bring on a decomposition of bones, and 

 render their fertilizing properties available to the wants 

 of growing crops, it is necessary to crush or grind 

 them ; and their immediate benefit is in proportion to 

 their fineness and rapid decomposition in the soil, 

 though ultimately they impart to the soil all their fer- 

 tilizing properties if they are broken to the size of one, 

 two, or three inches. In powder or dust their effect is 

 at first more powerful, but less abiding. So, too, the 

 like happens if the bones are brought into a state of 

 partial fermentation, so as to give off a strong odor 

 by mixing them with lime or ashes, or manure and 

 moisture, before they are applied to the soil, and there- 

 by hastening decomposition ; and, indeed, this is the 

 common practice, when it is desired to have them pro- 

 duce an immediate effect. To reduce bones to a 

 proper size for agricultural purposes, bone-mills have 

 been erected, consisting of a series of cast-iron rollers, 

 formed with deeply indented rims, and teeth progres- 

 sively more closely fixed. Many British farmers have 

 erected small machines, with two cylinders of cast- 

 iron, with teeth, which lock into each other, by which 

 they are broken into small pieces. We have had more 

 than sixty horse cart-loads of bones, which cost us 

 half a dollar a load, crushed in a plaster-mill, though 



