Byproducts are as old as hunting. Primitive man hunted for food, but took care not to waste the inedible parts of the animal. He clothed himself in the skin, made pins and ornaments from the bones and horn, and used stag's antlers for a pick (for example in the flint mines at Grime's Graves in Norfolk) and probably as a primitive tool for cultivating the soil. The lessons then learned have not been forgotten, and economy in the use of incidental materials has an important place in modern industry. A byproduct, as the name implies, is a commodity that arises incidentally but unavoidably, in the production of something else. If no use can be found for the byproduct it has to be discarded, and if it is noxious will cause pollution. A stern moralist may condemn any discard as waste, but it would be fairer to label a useless byproduct as an undeveloped resource — not every businessman is blessed with the ability to turn unconsidered trifles into gold. The preparation of cotton for spinning offers a telling example. The crop harvested from the cotton bush consists of seeds surrounded by cotton wool. In 1793 Eli Whitney invented a gin that simply and quickly separated the useful cotton wool from the unwanted seed. Nearly sixty years elapsed before men realised that the seed had its uses too: when crushed it yielded oil for soap-making, and the residue — oilcake - could be fed to cattle. The troublesome ‘wasted’ seed had become the raw material of a new industry.