“…The transportation data come from GIS databases developed by Atack from a variety of contemporary and retrospective sources including digitized maps, reports by various government agencies, compilations from travel guides, and the like (Atack, 2013). In particular, the basic Midwest rail data are from Paxson (1914) Data on canals are from Goodrich (1961), supplemented by 19th century sources such as Poor (1970) and various histories of the individual canal systems that provide dates on when specific sections of canals were opened to traffic (e.g., Whitford (1906) We use these GIS databases to construct a county-level panel from 1836 to 1861 with variables such as the number of railway miles in a county and indicators for whether the county had a port, river, or canal within its boundaries.…”