It was during this period that James Humphries Hogan (1883–1948), a designer with the firm, had the most impact on Powell & Sons. Hogan was apprenticed to the Powell & Sons firm at the age of fifteen, and it was the sole employer in his career. He designed extremely important windows for many cathedrals in England, and the finest of these are the two windows in the great central space of Liverpool Cathedral and the windows in St. Thomas Church, Fifth Avenue, New York City, which were fabricated between the World Wars. His influence in the area of stained glass is legendary, and his designs for tableware and serviceware, including the stemmed glassware he created specifically for the British Embassies over all the world, are without peer. He rose in the company, becoming Chief Designer in 1913, Art Director in 1928, Managing Director in 1933, and finally Chairman of the firm in 1946. In addition, Hogan traveled throughout the United States, as primary sales agent for the Powell & Sons firm. From the period between 1926 and 1928, he produced a ten-fold increase in the Powell & Sons stained glass sales in America. Unquestionably, he was a workaholic, and literally worked himself to death: returning from a long sales trip to the United States in late December 1947, he collapsed on 3 January 1948, and slipped in a coma-like state. He died on 12 January 1948, without ever regaining consciousness.