Nowadays the word recycling suggests piles of waste paper or bottle banks set up by local authorities so that paper and glass may be reprocessed and used again. It may also suggest scrap merchants who buy old car bodies to sell for the metal that can be salvaged from them. Recycling of this kind, which keeps up supplies of scarce raw materials, is a fairly new idea. But recycling has been occurring naturally since the Earth was formed four thousand million years ago.
Unable to display preview. Download preview PDF.