Shore durometer B, C, D, DO, E, M, O, OO, OOO, OOO-S, and R. Each scale results in a value between 0 and 100, with higher values indicating a harder material. Durometer, like many other hardness tests, measures the depth of an indentation in the material created by a given force on a standardized presser foot. This depth is dependent on the hardness of the material, its viscoelastic properties, the shape of the presser foot, and the duration of the test. ASTM D2240 durometers allows for a measurement of the initial hardness, or the indentation hardness after a given period of time.
South Shore, Chicago the 1920s generated not only a large increase in the area's population, but also greater diversity among its residents and in housing stock. Between 1920 and 1930 the population of South Shore jumped from 31,832 to 78,755. Many of these new residents were Irish, Swedish, German, or Jewish and had followed native white Protestants from Washington Park to live in South Shore's high-rises, single-family homes, and apartment houses. Institutions built in South Shore during these years reflected the community's growing diversity. By 1940 South Shore contained 15 Protestant churches, four Roman Catholic churches, and four Jewish synagogues. As African American