The extensiva uso of büiies, in variou brauchos of manufaoturing iudustry iu our citiea, is a fact but ]ttlo kuowu to people iu general. The valuó of thu artiole varíes accordiug to quality. Thigh bones of bullooks are macla iuto haudlos of tooth-brashes, and are of the moat valuó, being worth teu or twelve cents each, The jaw bonos rauk nest, and solí for oighteon dollar por tbousand; tha "hort" boues, which are thrown from thefamily table, are worth fir'ty couts per bushul.- . : dealer in New York pay $100 per day for boces, and thero are miny iu that city who are eagaged ni the business who pay an equal aiimmt. Ox hoofs ard worth $40 per ton; horse hoofs and slieep hoofs aud horus, $13 per toa. Oa thu anival of the bone.i ut the . factory, thu thigh aud juvr boncs are eleared of nistrrow; they aro thon thrown in a rasfc oaáldron, aiid boiled uutil all the maro W aud fatty subtanoe aíta'ebed to tfcojn aro thoroughly eitrauted. The fat is theii Bktmtned o3" aud placed uto coolera aud the bonos are deposited uto heaps, for a3sortmont. The turnors, tho jaws, and other boues suitable for buttons aro placed iu a socond pile; the bones adapted for bone-blaek ouustttute anoi.her grado, aud the rcmainder ara grouud iip for phosphates a:id maaures. Bone-black is usod bv eu"ar reñucrs, aud it ia worth 1'2 ícuts per pouiírl.