John J. Earley (1881-1945), an artisan and sculptor, is best remembered as the inventor of the Earley Process, a technique also known as polychrome, architectural, or mosaic concrete. He and his father, James Earley, ran a studio out of Manassas, VA, where they designed architectural sculpture for buildings for the Washington D.C. area, including the Library of Congress and the Franciscan Monastery.
Frederick W. Cron (b. 1906) wrote the book entitled, "John Joseph Earley: The Man Who Made Concrete Beautiful" (Ft. Collins, CO: Centennial Publications, 1975). Cron also wrote, "A Review of Highway Design Practices in Developing Countries" (Washington, DC: World Bank, 1975). He had retired from the Federal Highway Administraiton when he was the lead author of "Practical Highway Esthetics" (New York: American Society of Civil Engineers, 1977).
[Sources on Cron: Archives of American Art (Smithsonian Institution) Online; GU Library Hoya Search; World Cat].