Scope and Content Note
The papers of John Hays Hammond (1888-1965) consist primarily of correspondence, notebooks, sketches, technical papers, legal briefs, printed material, chronologies, and annotated photographs. The collection spans the period 1908-1965, with the bulk of the material falling between 1912 and 1953.
The collection is divided into four series: Notebooks , General Case File , Photographs , and Oversize . The Notebooks series, dated 1912-1918, contains reports by Hammond and his staff on experiments with radio control inventions. The General Case File represents the bulk of the collection. The third series, Photographs , includes detailed prints and negatives of Hammond’s staff and radio equipment. Several of the technical prints have explanatory notes pointing out specific electrical components or design differences. The Oversize series contains a photograph album featuring the Hammond Research Library in Gloucester, Massachusetts.
Ellison S. Purington, Hammond’s business associate and personal friend for over forty years who prepared these papers for transfer to the Library of Congress, arranged the materials in basic categories and included notes that point out significant segments of the collection. The addenda often provide background details not found in the documents.
Besides being a testimonial to Hammond’s scientific ingenuity, the papers contain material on early twentieth-century radio developments. Seeking technical assistance, Hammond corresponded with Nikola Tesla, Alexander Graham Bell, Irving Langmuir, Ernst F. W. Alexanderson, Lee De Forest, and others. These letters describe not only Hammond’s work, but also the research of those electronic pioneers. The correspondence with Alexander Graham Bell has added value because it partially describes his obscure activities in the development of the hydrofoil.
Certain case files are particularly useful in documenting Hammond’s inventions. The file of A. M. Austin, Hammond’s patent attorney, contains correspondence, original working sketches, and patent application papers dating from 1908 to 1913. The case file of Frederick Lowenstein includes detailed material on the controversial invention and use of the “audion” or triode electron tube. Other important case files cover topics such as intermediate frequency, frequency modulation (including the dispute over Edwin Armstrong’s priority in its invention), the Elmer A. Sperry dispute on inertial guidance patents, and radio control. The radio control case file, the most complete in the collection, documents Hammond’s basic experiments in radio control that led to his more important inventions of the intermediate frequency and frequency modulation.
Particular case files provide the scientific historian with valuable general information. A histories and chronologies file contains historical summaries, prepared by Hammond’s staff, which outline the contributions of the Hammond Radio Research Laboratory and others in specific radio inventions such as the triode tube, frequency modulation and intermediate frequency. Hammond’s thesis, “Telautomatics,” is a detailed technical history of radio control research and development before 1912.