Howes' papers are entirely concerned with his work at McGill and fall into four series: personal materials, teaching materials, research papers and consulting files, and papers concerning collective bargaining. Private files (16 cm) cover the period 1939-1962 and contain memoranda, correspondence and reports concerning Howes' appointments, salary and benefits, his engineering courses and Extension Department work, and the business of MAUT. Personal notes and poems from colleagues are also included. Teaching materials comprise 20 cm of lecture notes and laboratories notes for his course in radio design (1960), as well as a small number of files on equipment, the Engineering Faculty Summer School and student advisors (1944-1959). Research papers include a copy of Howes' doctoral thesis, as well as 18 cm of National Research Council applications, both his own and others', but all relating to acoustics, from 1948 to 1964. His work as a consultant is documented by a further 18 cm of engineering briefs and performance reports on radio stations in Ontario (1949-1960) and files of correspondence and reports on television transmission in Ottawa and Fredericton, as well as work undertaken for the U.S. Signal Corps. Howes' effort to justify the construction of the anechoic room in the McConnell Engineering Building resulted in 18 cm of plans, reports, and correspondence with industries interested in sound-proofing (1958). There are also some general research notes on noise levels in the Engineering and Physical Sciences buildings at McGill. Finally, Howes' involvement in the question of collective bargaining rights for engineers is attested by 13 cm of notes and correspondence, largely with professional engineering associations and with political figures such as Senator A.K. Hugessen and Prime Minister McKenzie King.