1274. Horns and hoofs differ from bones in containing a larger quantity of animal matter. From 500 grains of ox-horn, Hatchett obtained only 1.5 grains of earthy residuum, and not quite half of this was phosphate of lime. The shavings or turnings of horn form an excellent manure, though they are not sufficiently abundant to be in common use. The animal matter in them seems to be of the nature of coagulated albumen, and it is slowly rendered soluble by the action of water. The earthy matter in horn, and still more that in bones, forms the most valuable portion of the manure, and renders it very durable in its effects.