Philadelphia Directories

The Betsy Ross house is not only one of the most famous sites of Philadelphia history, but the subject of one of the earliest-ever attempts to use deduction and logic with directory entries-- in this case to try to determine whether Betsy Ross Claypoole lived in the house preserved and celebrated as hers. This site argues that the earliest attempts at it at about the turn of the 20th century were wrong, and that the Betsy Ross House was in fact probably where she lived. This describes their process:

"To determine whether the Claypoole residence in 1785, then numbered '335 Arch Street,' corresponds with the present site of the Betsy Ross House, one must determine first, the numbers assigned to the Betsy Ross House under the Biddle system from 1791-1857, and second, whether that number or numbers correspond with the location numbered '335 Arch Street' in the MacPherson directory. … One might independently determine whether number "335 Arch" of 1785 corresponds with number "89 Arch" of 1791 by examining the individuals listed between Second and Third Streets on the north side of Arch during this six year period. One can arrive at a rough correspondence of numbers by finding an individual who remained stationary from 1785 through 1791, thus appearing in both directories. One then counts the number of houses between the Claypoole location (335 Arch) and the stationary individual in 1785 and then counts this number in the same direction from the stationary individual's residence in 1791."

The New York Public Library's extensive blog post on the history of American city directories, including those of Philadelphia, where the first two American directories were published in 1785.

FamilySearch.org has a genealogy wiki which covers American directories.

Genealogy.com has a good guide to using directories in genealogical research.

Genealogy Blog offers a fairly long blog post about using directories in genealogy.

Finally, the genealogy links site Cyndi's List gives links to many pages about city directories, though most are not of Philadelphia.

This is Dr. Amy Hillier's extensive application of historical GIS to W. E. B. DuBois's 1896 study The Philadelphia Negro. Her work allows the interactive research into turn-of-the-century residents of Philadelphia's Seventh Ward (Spruce Street to South Street, 6th Street to 27th Street).

The project gives some idea as to the kind of research powers the use of geographic information systems allows: "The “Identify Property” tab allows you to search for a specific property, either by typing in the address or searching on the map, to see who lived there in 1900. The “Find Person/Property” tab allows you to look for an individual or property that meets a certain profile (such as Irish immigrant who has children). The “Create Thematic Map” tab allows you to view the data spatially, through a series of map layers. You can move back and forth from one tab to the next, so if you make a thematic map and want to know more about the people in particular properties based on the spatial pattern, switch back to the “Identify Property” tab."