Blacktop: How Asphalt Paving Came to the Urban United States

Asphalt was first used as a paving material in U.S. cities in the 1860s. Early applications were largely unsuccessful because its chemical composition was ill-understood and methods as well as machinery had to be developed to apply it with success. Competent chemists and increasingly experienced contractors gradually led to a mastery which by the early twentieth century made asphalt the commonest paving material, surfacing 90 percent of U.S.streets and highways. Nationwide contacting firms, the appearance of railroad mixing plants, and the invention of tank cars to distribute plentiful Western petroleum cheaply played a crucial role in the success of asphalt.