Understanding how labor was mobilized in response to the shifting pattern of labor demand created by industrialization requires an examination of the mechanisms that labor market participants created to convey information and facilitate transactions between job seekers and employers. A complete account of these institutions would require considering all the transactions that took place in the labor market. Since the late 1920s, a number of studies have attempted to do just this through surveys of workers in particular industries or locations (De Schweinitz 1932; Myers and Maclaurin 1943; Myers and Shultz 1951; Reynolds 1951; Rees and Shultz 1970; Granovetter 1974; and Corcoran, Datcher, and Duncan 1980). The sources available for the nineteenth century will not support such an investigation; nonetheless, it is possible to piece together from a variety of alternative sources a relatively clear picture of how labor markets worked and how they responded to the challenges created by American economic growth in this period. The account that emerges from these sources lacks some of the quantitative precision of more recent surveys, but it more clearly reveals the dynamics of labor market evolution over time than is possible based on the sort of snapshot picture provided by most worker surveys.

It is apparent from the available sources that, as is true today, most labor market information was communicated through “informal” networks of friends and relatives. When in place, such networks provided a highly efficient and low-cost mechanism of conveying labor market information.