246 FERTILIZERS. 



The remaining gelatine is decomposed, and its nitrogen converted into carbonate of ammonia 

 and other ammoniacal salts : these are retained mostly by the earthy part of the bones. As 

 it regards the changes which antediluvian bones have undergone, it is evident that under favo- 

 rable circumstances, they have retained almost perfectly their composition. Thus the bones of 

 the mastodon, found in marl in Orange county, are perfect where there is a compact stratum of 

 peat upon the top of the formation. Renewed fresh or rain water is denied access to these 

 bones, and hence their perfect preservation ; it is evident, too, that the waters in which they 

 have been so long immersed, have not contained, at any time, carbonic acid, otherwise they 

 would have been corroded. All the bones of quadrupeds which die, and have died upon the 

 surface and have been exposed to the ordinary atmospheric agency, have been destroyed after 

 a few years of exposure only — scarcely a trace of a skeleton of an animal remains upon the 

 surface after eight or ten years exposure. 



The quantity of crushed hones required per acre. From five to six bushels of bone dust per 

 acre may be employed to advantage on lands which are to be sown with several crops of grain, 

 or a rotation in which wheat and oats or maize are to be applied. A bushel of bone dust weighs 

 fifty pounds, if they have been boiled for glue : it is worth fifty cents per bushel. The dust 

 may be applied immediately after, or immediately before the sowing of the seed. It becomes 

 immediately active in forwarding the crop, having, in the course of boiling, absorbed conside- 

 rable water, which replaces the fat and gelatine, which favors the solution of the remaining 

 animal matter. The effect of boiled bones is more immediate than those which have not been 

 boiled, but the duration of their influence is of course proportionally less. One of the most 

 valuable effects of bones is the prolonged effect which follows their use ; this is known to con- 

 tinue for twenty or thirty years. It is customary, however, to repeat their use upon each suc- 

 cessive rotation. The crops which require phosphate of lime are the cereals, as wheat and 

 maize particularly ; flax and hemp ; turnip and other roots. But wheat and maize feel the 

 favorable influence of bone dust, and indeed it is scarcely possible to raise a good crop of 

 either, except by the use of the phosphates. This remark is intended to apply to those districts 

 which have been under culture a half century or more, and have borne many exhausting crops 

 of the cereals, tobacco, flax and hemp. 



Phosphate of lime acts directly, and in virtue of its constitution, and the relation it bears to 

 the vegetable and animal nature. It does not, like lime, afiFect the chemical combination of 

 other bodies ; that is, it does not decompose them. In the soil the phosphate is the commi- 

 nuted apatite, or the tribaric phosphate, which jjossesses but little solubility ; and hence the 

 probability that apatite, provided it should be found in suflScient abundance, might be employed 

 as a fertilizer. Its sparing solubility may appear objectionable at first, still, if apatite is con- 

 verted into the superphosphate, by oil of vitriol, its solubility is increased, and its effects, as a 

 fertilizer, are seen as speedily as where bones are employed. 



Bones and other phosphates, then are articles of food for the plant ; and the theory of their 

 action is simple. Where bones and the phosphates are converted into the superphosphate, by 

 oil of vitriol, sulphate of lime is formed, and hence we add to our fertilizer sulphuric acid, 



