Shore durometer "durometer" (ISV "duro-" and "-meter"; attested since the 19th century), but today that name usually refers to Shore hardness; other devices use other measures, which return corresponding results, such as for Rockwell hardness. There are several scales of durometer, used for materials with different properties. The two most common scales, using slightly different measurement systems, are the ASTM D2240 type A and type D scales. The A scale is for softer ones, while the D scale is for harder ones. However, the ASTM D2240-00 testing standard calls for a total of 12 scales, depending on the intended use: types A,
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