264 FERTILIZERS. 



This composition is quite similar to hair, horns, hoofs, etc., and hence our experience would 

 justify the conclusion that, like them, it must act beneficially as a fertilizer, per se, also. Farmers 

 then will not, under an erroneous idea, consume the gelatine of the solid animal matters. All 

 the advantage which can be claimed now, for the combustion of those parts, is the more pul- 

 verulent condition of the earthy parts which remain. It is unnecessary to speak of the modus 

 operandi of bones, since, from what has already been said, it is plain that all their elements 

 must enter into the composition of vegetables, and especially into their seeds. The young 

 growing animal obtains the solid parts of which its bone consists from the milk of the mother, 

 in the first instance, and afterwards from the grass and herbage upon which it feeds. 



Methods which have been adopted for securing the efficacious action of bones. Bones, in the 

 first place, should be reduced to powder. The object is to bring the bone into direct contact 

 •with the roots of the vegetable, and also to facilitate the action of atmospheric agents upon it. 

 It is well known that bone may be buried in the earth for centuries, without impairing to a 

 a great extent their integrity, and even, under certain circumstances, are preserved, without 

 loss of their animal matter, for more than two thousand years. They should, therefore, be 

 ground either to a coarse or fine powder, if we, in our day, would reap the reward of their 

 application. In addition to the simple pulverization of bones, other additional means are some- 

 times instituted for hastening their action. Bones, then, after being pulverized, are made into 

 heaps, and coveredjwith earth, for a week or two prior to their intended application. In this 

 state the heap becomes hot by the fermentation which ensues, and the changes which are 

 thereby induced prepare the nutriment more speedily for the young plant. The powder, 

 softened by fermentation, is strewed by side of the plant : it is, in fact, to be used as a top 

 dressing, and is well adapted to use in drill husbandry. Sometimes the powder is fermented 

 with the excrementitious matter of cattle, and it seems to be established, by experiment, that 

 when fermented, its effects are increased, and its value enhanced, or at least it is better than 

 dry bone dust. The object which it is designed to effect by these and other chemical agencies, 

 is, to diminish the cohesion of its particles, and increase its solubility. In order to bring bone 

 dust into the most active and energetic state of which it is susceptible, by the foregoing means, 

 it should, according to Johnston, be exposed for two or three months to fermentation, when 

 the gelatine and earthy matters will become completely softened, and more perfectly resemble 

 the condition of guano. 



Another mode which has been adopted, and which seems to effect the objects desired more 

 perfectly than any other, is by solution in sulphuric acid. The apparatus required for dis- 

 solving bones, is a large iron kettle, or a large wooden tub, into which the crushed bones 

 are introduced. Upon the bones one half their weight of water maybe poured, and, after stir- 

 ring the mixture, as much by weight of a strong acid may be added, and still stirred, until the 

 materials are incorporated. The proportions are varied by difTerent English farmers ; but 

 it is necessary that water should be first applied in order to prevent the charring effect of strong 

 acid upon animal matters, which, if it take place, arrests in a measure the farther solvent action 

 of the acid. It can not be supposed that if an excess of acid is added that it will be lost, in- 



