Fires were common in American cities in the nineteenth and early twentieth centuries. Their destructiveness constantly prompted environmental redevelopment on a small scale. Great fires like those in Chicago, Boston, and Baltimore took place comparatively rarely. They were, however, common enough to constitute an important natural force for urban renewal on a major scale in many large cities in this period. As this study indicates, they temporarily eliminated an important barrier to change, the physical durability of structures. This lifted a wide variety of other powerful demand- and supply-side barriers to environmental improvement, stimulating extensive structural and infrastructural redevelopment and, depending on the timing and extent of the destruction, considerable spatial redevelopment as well.

Clearly, great fires played an important part in the environmental development of many American cities. The purpose of this book has not been to identify and analyze precisely the role that these disastrous conflagrations played in the process of city growth, however. Instead, its goal has been to explain the frictions impeding the process of environmental development, the difficulties of environmental adaptation, which account for the terrible fire, pollution, congestion, housing, and other environmental problems cities suffered in this era. The great fires and reconstructions of Chicago, Boston, and Baltimore have merely provided the historical context in which these barriers to improvement have been described.