phosphate of lime, thirty-eight pounds fat and gelatine, of which about five pounds are nitrogen; of the phosphates about fifty per i cent. are phos phoric acid. If all the nitrogen s preserved, 100 pounds of bones would furnish the amount ex pended in growing a bushel of wheat; 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 curers, 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 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, gelatins, 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.