When Historic Documents Don't Agree...
One of the aims of historical research before an urban excavation is to identify an occupation history for each lot in the project area. By knowing who lived where and when, the archaeologist can tell which family, business, or factory most likely created an archaeological feature.
Archaeologists develop occupation histories for lots by cross-referencing information from historical documents such as the U.S. Census, city directories, tax assessments, and Sanborn Fire Insurance maps. These documents can show the address and boundary lines of each city lot, who owned it and who lived on it. The researcher has to be careful. These historical documents can be missing information or even contradict each other. In San Francisco, the task is further complicated by the great earthquake and fire of 1906 that destroyed the city’s Hall of Records, and many of the its public records.
Kate St. in the South of Market area of San Francisco is an example of the difficulties of using historic documents to develop occupation histories. Addresses and lot boundaries in cities often changed as areas were developed. During the early 1880s houses on Kate Street were demolished to make way for factories. However, the earliest map of Kate Street that showed the location of addresses and lot boundaries was the 1887 Sanborn Fire Insurance map. Without earlier maps it was difficult to know where addresses and lot boundaries from 1850s-1870s dwellings were located. Without this information, archaeologists would not be able to determine which households created or were associated with archaeological feature found during excavation.
San Francisco city directories from the 1850s-1870s weren’t much help as they only gave vague listings for where people lived e.g. “John Wendt, r. [residence] Kate [Street] near Bryant [Street].” To add to the problem, the numbering of addresses on Kate Street before the 1880s was not consistent and the numbers tended to jump around. To resolve this type of confusion, the archaeologist would normally refer to the U.S. Census records, which usually lays out the sequence in which people lived on a street. The 1880 Census enumerator of Kate Street however, did not list the whole street at one time but jumped back and forward between different streets.
Eventually, the conundrum of who lived where on Kate St. prior to the
1880s was determined by comparing the censuses of 1870 and 1880 with
documents such as voting records, and land use and tax maps.