BONES. The importance of bones is gener ally underestimated. They form the framework of all verterbrate animals, are of great value in many of the arts, and crushed, form. one of the most valuable of manures. They consist in 100 parts—of mineral matter, fifty-six, the balance being gelatinous and other destructable matter. The mineral portion—the valuable part—con tains about fifty per cent. of phosphate of lime, of which twenty-four per cent. is phosphoric acid. The gelatinous part of the bone consists of car bon, hydrogen, oxygen, nitrogen, and sulphur. One hundred parts of gelatine of bones produce,. when fermented, twenty-two pounds of ammo nia, together with carbonic acid. Sulphur is also an ingredient of plants. Phosphate of lime is soluble in all acids, and we may say that all the the phosphates are soluble in an excess of acid. When bones are surrounded by fermenting or ganic matter, such as is offered in a manure or compost heap, the phosphate of lime is dissolved in the humidity by the carbonic acid which is constantly being evolved by the fermenting mass. This operation is more or less prompt, to the activity of the fermenting heap. In the field, where carbonic acid is always present, thia process is constantly going on; but, owing to they presence of the cartilaginous or gelatinous por tion which surrounds the particles of phosphate,, the action is less apparent on a large bone than if it were in powder, and the finer the powder the more rapid the decomposition. Bones vary much in their composition, according to the age •or variety of the animal. The amount of mineral matter is less in a young animal than in an old -one, and the quantity increases gradually with age. Schreger found that the bones of a child contain one-half of phosphate in the entire mass of earthy matter, while those of a full-grown person give four-fifths, and an aged person not less than seven-eighths. The bones of adults contain less water than those of children. When a bone is sufficiently digested in muriatic acid, the mineral part is dissolved, leaving the gelatine, or cartilage, intact, which retains the original form of the bone. Large amounts of gelatine, or glue, are thus made. That portion of the bone dissolved in the acid consists of phosphate of lime and magnesia, fluoride of calcium, and car bonate of lime, with small quantities of salts of potash and soda. All who work the soil know that bones are most valuable applied to all cereal crops, and the grasses and in root crops. The following method of preparing bones on the farm, is from Mr. Pusey, a practical English farmer : The process depends upon the fact that bones consist, to the amount of one-third their weight, of cartilage or animal matter, which, under the influence of warmth and moisture, readily decomposes (ferments or decays) and loses its texture, so that the bones fall to dust. From the closeness and solidity of the bony structure, decay is excited and maintained with some difficulty. A single bone, or a heap of bones, never decays alone, but dries and hardens on exposure. If, however, bones in quantity be brought into close contact with some easily fer mentable moist substance, but little time elapses before a rapid decay sets in. So, too, if fresh crushed bones are mixed with sand soil; or any powdery matter that fills up the spaces between the fragments of the bone, and makes the heap compact, and then are moistened with pure water, the same result takes place in warm weather, though more slowly. The practical process may be as follows : The bones, if whole, should be broken up, as far as convenient, by a sledge-hammer, and made into alternate layers with sand, loam, saw-dust, leached ashes, coal ashes, or swamp muck, using just enough of any one of these materials to fill compactly the cavities among the bones, but hardly more. Be gin with a thick layer of earth or muck, and as the pile is raised pour on stale urine or dung heap liquor enough to moisten the whole mass thoroughly, and finally, cover a foot thick with soil or muck. In warm weather the decomposi tion goes on at once, and in from two to six or more weeks the bones will have entirely or nearly disappeared. If the fermentation should spend itself without reducing the bones sufficiently, the heap may be overhauled and built up again, moistening with liquor manure and covering as before. By thrusting a pole or bar into the heap, the progress of decomposition may be traced, from the heat and odor evolved. Should the heap become heated to the surface, so that am monia escapes, as may be judged by the smell, it may be covered still more thickly with earth or muck. The larger the heap, the finer the bones, and the more stale urine or dung-liquor they have been made to absorb, the more rapid and complete will be the disintegration. In the heaps, horse dung or other manure may replace the ashes, etc., but earth or muck should be used to cover the heap. This bone compost contains the phosphates of lime in a finely divided state, and the nitrogen of the cartilage, which has mostly passed into ammonia or nitrates, is re tained perfectly by the absorbent earth or muck. When carefully prepared, this manure is adapted to be delivered from a drill-machine with seeds, and, according to English farmers, fully replaces in nearly every case the super-phosphate made by help of acid. And this we can indorse. As showing the value of bone phosphate in re storing fertility to soils worn under successive croppings of wheat, we append the following from the report, the results as stated by a com mittee of experts: An analysis of the grain of wheat, that part of the plant which is not again returned to the soil, shows that nearly fifty per cent. of the ash constituent is phosphoric acid, and this is equally true of nearly all the cereal crops. When it is considered that our most fertile soils contain a very small percentage of this essential element, and that in many soils there is scarcely a trace, its real importance in an agricultural point of view can not be questioned. Under our system of cropping, the mineral elements first exhausted are the phosphates, and while conced ing that no special manure can be regarded as a substitute for barn-yard manure, the question arises, can the farm be made to sustain its pro ductiveness by the use of manures made solely from the products of the farm ? Every bushel of grain and roots; every pound of cheese, butter, and wool; every ton of hay and straw sold, carries away a portion of the organic mineral elements of the soil ; and, if something is not added to supply this deficiency beyond the ordinary accu mulations of the barn-yard, gradual but certain deterioration of the soil must necessarily follow.
The largely increased yield of wheat by the use of clover and plaster on fields partially exhausted by tillage, the clover being plowed under as a green crop, has led some to suppose that nothing else is needed to retain or restore the fertility of their land. Without doubt there are important benefits derived from the use of clover and plaster as fertilizers; indeed, a soil may have an available supply of minerals for a wheat crop of forty bushels per acre, but if deficient in ammonia, the crop, depending solely upon the atmosphere for its supply, the yield will not exceed eighteen or twenty bushels, under the most favorable circum stances of weather, ammonia] manures being necessary to increase the yield. Yet, valuable as is the clover crop in furnishing this essential organic matter to the cereal crop, it adds no mineral matter to the soil. The clover crop and the ordinary accumulations of the barn-yard are not sufficient to restore the mineral elements of which the soil is deprived by successive grain crops, and it is necessary to resort to other fertil izers to restore this deficiency. The phosphates, among the mineral elements, necessarily first disappearing on a wheat farm, the value of bone dust and super-phosphates can not be questioned, the former containing about fifty per cent. of phosphoric acid. But it will not do to rely upon this alone, as will be apparent when the constitu ents of bone-dust are considered. One hundred pounds of raw bones may be estimated to con tain eleven pounds of water, forty-five pounds phosphate of lime, thirty-eight pounds fat and gelatine, of which about five pounds are nitrogen; of the phosphates about fifty per cent. are phos phoric acid. If all the nitrogen is preserved, 100 pounds of bones would furnish the amount ex pended in growing a bushel of wheat ; an appli cation of 400 pounds per acre would furnish only twenty pounds of nitrogen, about one-third the quantity contained in clover, equalling one ton of hay. The committee think, that in connection with a proper use of clover as an organic fertil izer, the wheat crop may be largely and profit ably increased on impoverished soils by an appli cation of 300 to 400 pounds of bone-dust per acre ; on soils not greatly impoverished a smaller quantity may be used. It is sometimes the case that bone-dust, when no other manures are used, fails to materially benefit the wheat crop to which it is immediately applied. This is attributed chiefly to a deficiency of ammonia ; and when the wheat crop, under such circumstances, is only slightly benefited, the clover sown the suc ceeding spring, which obtains a large proportion of its ammonia through its broad leaves from the atmosphere, will be largely increased by the de composing phosphates applied in the fall, thus accumulating ammonia for the succeeding wheat crop. The failure of bone-dust to benefit the crop to which it is first applied is owing also to its undecomposed condition. In one instance given, 500 pounds per acre was applied to corn without benefit; the second year it helped the corn, and the third year after the application, the yield of wheat was four bushels per acre greater than the product of land in the same field not so dressed. On soils where no phosphates have been applied, an immediate fertilizer being needed for a summer crop, a well-prepared super-phosphate is recommended as preferable to undecomposed phosphate. The effects of a properly-prepared super-phosphate upon a turnip crop are frequently almost magical, the crop being increased four or five fold by an application of 400 to 500 pounds per acre. When used for wheat and clover, it should be well mixed with the surface soil, in a partially fermented condition, before the wheat is sown. Ample time will thus be given for a portion of the phosphates to be decomposed, and taken up in solution by the roots and plants, and organized in the grain. After the wheat crop has matured, the clover sown in the spring will be still further benefited by the gradual decomposi tion. Ashes, both leached and unleached, are highly valuable as additional fertilizers in fur nishing potash and other minerals for the culti vated crops. In closing their report, the com mittee state, that under the system of cropping, so widely prevalent, the most careful preparation and use of all the available bones in Michigan will not replace the phosphates withdrawn from the soil by the frequent recurrence of the wheat crop; and that, to increase the productiveness of their lands, farmers must lessen the proportion of acres annually devoted to wheat, keep more stock, and thus manure more highly from the products of the farm, and with other valuable fertilizers. One of the best means the editor of this work has ever found for making super-phosphate is in the bone-black, or animal charcoal, used in refining surgars, and for filtering any substances requiring refining. Bone-black is made by burning bones in a closed vessel, by which they are converted into bone charcoal. They are then ground and used in the refineries. The waste bone-black about twenty-five to forty per cent. of the quan tity used—which accumulates in twelve months, is no longer of value in the refining. This is treated with sulphuric acid and converted into, super-phosphate of lime and sold for fertilizing purposes. Bone ash is obtained by burning bones with access of air or oxygen. Thus the organic matter, gelatine, etc., is burned out, and the fri able residue is easily acted on by sulphuric or other acids. When mills for crushing are not available, and bones and sulphuric acid are cheap, this is an easy way of obtaining bone ash, which may be converted for use by means of sulphuric acid.