Charles H. Purcell operated as Chief Engineer of the San Francisco-Oakland Bay Bridge from 1933-1936; Purcell worked with the noted civil engineer, Daniel E. Moran, a designer of the George Washington Bridge in New York City and an expert on the construction of deep-water foundations; a central anchorage was needed to support a 2-mile long bridge in the 1930s, and Purcell and Moran collaborated on the methods to erect a 508-foot caisson that is lodged in 100 feet of mud down to bedrock; it rises to 288 feet above the Bay; Purcell was the nephew of architect William Gray Purcell, who practiced in Oregon and briefly in California in the 1920s and 1930s;