E40°: An Interpretive Atlas
By Jack Williams. Charlottesville and London: University of Virginia Press, 2006; 277 pp.; illustrations, index; paper, $30.00.
The curious title of this book, E40°, refers to the deviation of the axis of the Appalachian Mountains from true north. The brevity of the title masks the rich and evocative analyses illuminating the geophysical and economic factors that shaped the urban form of 42 towns from Alabama to Maine within the Appalachian Mountain range. The urban form is the combination of the pattern of a town's street grid in relation to its residential, governmental, commercial, and industrial activities.
Despite the varied geophysical environments and economic circumstances of each of the towns appearing in the study, all developed compact centers organized in a regular geometric pattern. According to the author, the concise urban form creates a favorable figure to ground (built environment to undeveloped space) ratio. This ratio is seen as ecologically advantageous because it fosters physical diversity, which is inherently flexible and responsive to environmental change.
Varying characteristics of street grids such as shape, building density, and the patterns of relationships among the different residential, commercial, industrial, and governmental areas, encourages regional differences in our "collective culture." While the grid form was ubiquitous during the 19th century, its manifestation in specific locales varies considerably. These phenomena lead to the evolution of specific urban forms that the author labels the "Wagon town," "Courthouse Square," "River town," "Railroad town," "Alluvial town," "Coal town," and "Coastal town." The urban landscapes associated with each of these town types embody and frame cultural experiences and expressions that persist through time and in the collective memory of its citizens. In other words, these towns create a persistent sense of place.
Through the use of graphs and maps, visual representations of the various urban forms are presented in a clear manner. The author makes use of computer mapping technology (Geographic Information Systems, or GIS) to dissect the settlement pattern of each town into its component parts. Thus, building footprints, street grids, topography, and railroad alignments become separate map layers in the GIS. These map layers isolate individual aspects of the urban form that might otherwise be obscured when viewing a more traditional map.
In addition to GIS-generated maps, E40° is punctuated by evocative historic photographs of many of the towns presented in the study. One photograph in particular is worth noting: the rail yard in Williamson, West Virginia, from around the 1930s. In the photograph, row upon row of coal cars extending as far as the eye can see wait to be moved out to industrial centers. These long trains "moved out every hour, twenty-four hours a day." The photo communicates the dense urban form, even within a rural area of West Virginia.
E40° provides us with a deeper level of understanding of the ways that these towns evolved and the lessons we can learn from studying them. After examining the urban form of the towns in six chapters, Williams presents a strong synthesis of the data in the final chapter, where he draws a key conclusion: that compactness of urban form is universally the most sustainable kind of settlement pattern. Ironically, while the compact urban form may be the most sustainable, all the towns in the study depended upon unsustainable extractive industries—cotton farming in Alabama, bituminous coal mining in West Virginia and Kentucky, anthracite coal mining in eastern Pennsylvania, and fishing off the coast of Maine—as their economic base. How, then, can modern economic bases be sustainable and at the same time foster the compact urban form? This reader did not find a clear answer in the book.
Historical factors such as the demand for housing by returning soldiers after World War II, the increase in mobility due to the automobile, and consumer information broadcast from televisions have stimulated and supported today's urban sprawl. Williams suggests that these factors have served to homogenize our landscapes and culture. However, recent economic and demographic trends may favor a return to the compact urban form. For example, the high price of gasoline may serve to restrict mobility. The retiring baby-boomers are increasingly moving out of the suburbs and into smaller urban neighborhoods.
Other GIS tools could have lent a more quantitative component to Williams's study. For example, GIS network analysis can model the connectivity of a street grid, thus making it easier to compare one town's street grid with other street grids. Viewshed analysis, another GIS tool, can identify the frequency with which areas in a town can be seen from selected vantage points.
A GIS viewshed map of the areas seen from the U.S. Customs House in Belfast, Maine, for example, could have supported the author's point that the Customs House was sited in such a manner as to keep a watchful eye on the harbor. Furthermore, nearest neighbor analysis can provide an assessment of the distribution of towns within a region in terms of whether they are clustered or evenly or randomly distributed. The E40° study provides a good dataset to apply these GIS tools.
The book challenges the reader to think more critically about land use development decisions and their consequences. Thus, future urban forms should be a conscious collective choice, not a de facto result. The contribution of E40° is the lesson that by examining and learning from past urban forms we are in a better position to choose future forms.
John J. Knoerl
National Park Service