The way that we manage our waste materials is a sign of the times. In our agrarian past, throwing garbage out into the street for roving pigs to eat seemed like a perfectly reasonable method of waste management, since most of what we threw away was organic material that increased the bulk of the pig and eliminated residuals we did not want. As manufacturing became a larger part of industry and materials had potential for recycling we saw the advent of the another kind of scavenger, the "junk man," who pulled from the waste stream those materials that had value. This practice increased during the Great Depression and even more so during World War II. During the war there were shortages of metals and cloth as many raw materials were diverted from domestic use to war needs. People got into the habit of conservation. Things were...