He is now known primarily for his work as a philatelist who specialized in the collecting of, and writing philatelic literature on, United States postage stamps.
Along with Max G. Johl, he co-authored the landmark “United States Postage Stamps of the Twentieth Century” (Vol.
King was active at the Collectors Club of New York, serving as president in 1933.
King was elected to the American Philatelic Society Hall of Fame in its first group of fifteen philatelists in 1941.
The firm designed a number of Carnegie Libraries around the United States, including those in Cleveland, Ohio, Honolulu, Hawaii, and South Worcester, Massachusetts, as well as the Eaton Memorial Library at Tufts University.