The study of local history allows us to go from the general to the specific, from the population to the individual, and from the neighborhood to the house or block. The UCHS website now includes links to four maps designed to reveal general patterns and the characteristics of individual blocks or houses. The maps are based on Google Maps. They superimpose color-coded maps on top of standard maps of the street grid. By clicking on an individual property, one can see the exact value for that property. Google maps can include up to ten layers which can be reviewed individually or simultaneously.
The first two maps (Map 1, Map 2) cover the neighborhoods of Spruce Hill, Walnut Hill, Garden Court, and Cedar Park. The first examines changes in the racial composition of blocks between 1950 and 1990. The data come from the U.S. Censuses of Population and Housing and were made available by IPUM-NHGIS at the University of Minnesota (https://www.nhgis.org/). Each layer presents the data from a different census. Clicking on the various layers reveals how these neighborhoods were affected by “white flight” and changes in housing laws designed to limit racial discrimination in housing. Clicking on an individual block shows the proportion Nonwhite reported for that block.
The second map (Map 2) examines the values of owner-occupied houses reported in the 1940 census. Each layer provides the data for part of the area. The color coding compares the value reported for each house to all owner-occupied houses in Philadelphia. The reported dollar value for a house can be found by clicking on it. The data for this in the next two maps were made available by IPUMS-USA at the University of Minnesota (https://usa.ipums.org/usa/).
The other two maps (Map 3, Map 4) examine the houses in Hamilton Village. Many of these houses have been replaced by parts of the University of Pennsylvania. The map for 1920 provides information on population density. Each house is coded according to the square footage of the plot of land per resident. Clicking on the property shows the number of people living there and the exact density figure. The map for 1900 provides information on home ownership. Each house is coded according to whether it is owner occupied with a mortgage, owner occupied without a mortgage, or rented.
Housing data for 1950 and 1960 for household heads. 1970 and 1990 give population data. Later layers overwrite earlier data.