As ever more people crammed into ever more dilapidated quarters, the consequences of crowding became blatantly apparent--to both eye and nose. New York, it was widely agreed, was the filthiest urban center in the United States; Boston and Philadelphia gleamed by comparison. This dubious distinction, ultimately rooted in the perverse dynamics of the housing market's response to immigration, was exacerbated by the city government's hands-off approach to the increasing production of garbage....Great heaps of mud, garbage and animal excrement piled up in the streets, forming a stinking mash labeled "Corporation Pudding" by a disgusted citizenry. To this base were added the noxious by-products of slaughterhouses, tanneries, dyers, distilleries, glue works, bone boilers, and stables, which had once been banished to the periphery but had now been overtaken by rapid expansion and were back in town. Roving herds of scavenging pigs made some inroads on the resulting accumulation, but what goes in must come out, and t