The bulk of Gill's papers concern his consulting work for the mining industry and for government. Only two small files relate to his teaching career. Gill's work as mining consultant is documented by 124 maps, 48 designed by Gill himself, showing structural geology of various regions in eastern Canada, and mineral deposits of gold, iron, zinc and molybdenite, not only in Canada, but also in the Malartic gold fields in Peru (1929-1968). The papers also contain his report on iron ore in Labrador (1929) and two reports by W.F. James and J.E. Gill to the Newfoundland government, assessing prospects for gold in the Rainbow and Kayak Concessions, Labrador (1933), areas prospected by R.B. D'Aigle, see his papers, Section IX: Professions And Trades. IX). Three field notebooks record summer research expeditions (1935, 1947-1948). Three reports by Peter Eakins, a former student of Gill, describe the Malartic mine (1951, 1955-1956); there is also a report by Eakins on the Wasa Lake Goldfield (1950), and one by J.B. Gilliatt on the Wabana Iron Mines (1949). Gill also raised a file of correspondence and reports on Newfoundland mineral resources (ca 1955-1969). Finally, there are two boxes of petrographic slides, one with laboratory reports, a box of mineral samples collected for the Québec Ministry of Mines, and 4 photographs of mining concerns with which Gill was involved. His teaching activities are reflected by a file of plans, reports and memoranda on the organization of the Geology Department Map Library (1959-1969) and an outline with some draft chapters of a student's thesis (1969).

This file contains ephemera related to 50th reunion for the Arts class of 1912. Includes a name tag, dinner program, and map of McGill campus.

This file contains a folded sheet describing a walking tour that highlights William Osler's experiences during the time that he spent studying and teaching at McGill, prepared for the 150th anniversary of Osler's birth. Includes photos, map, and satellite image of the area.

The Harold Spence-Sales fonds at McGill’s Canadian Architecture Collection primarily contains project records related to Harold Spence-Sales' career as an architect and urban planner. The bulk of the records pertain to projects that Harold Spence-Sales worked on as well as corresponding financial, administrative and office records.

The fond heavily documents projects that Harold Spence-Sales worked on during the 1970s-1980s in British Columbia and in Quebec during the 1940s-1960s. Other projects that Harold Spence-Sales worked on across Canada and internationally appear intermittently throughout the fonds. The Oromocto community planning project that Harold Spence-Sales worked on from 1955-1958 in New Brunswick is particularly well documented. Harold Spence-Sales designed Oromocto to be a military town. Before He transformed Oromocto into a military town it was a defunct 19th century shipbuilding town. The Oromocto project is considered one of Harold Spence-Sales most important urban-town planning projects.

Apart from administrative, office and project records, the fonds also contains records that relate to Harold Spence-Sales professional activities outside of his work as an architect and urban planner. For example, awards and honors that he received and records related to his involvement in architectural and urban planning associations. Additional professional activities include: his involvement in creating exhibitions, curating architectural-themed magazines and periodicals as well as copies of publications that he worked on solo and in collaboration with John Bland.

The fonds also contains fourteen boxes of Harold Spence-Sales personal records. The personal records primarily cover Harold Spence-Sales interest in art, creative pursuits, family activities, family genealogy, personal finances, last will and testaments as well as his decline in health and his death. Within the fourteen boxes that have been cataloged as personal records, there are also materials related to Harold Spence-Sales professional activities. For example, awards that Harold Spence-Sales received and records related to exhibitions and artistic projects that he worked on.

Collection consists of an illustrated manuscript containing a map and brief guidebook to Paris landmarks, created by Nicole Allardet probably during the 1940s or 1950s. The item is inscribed to Vivienne Horne. A folded booklet on heavy grey paper, the guidebook contains twelve panels, ten of which feature a gouache illustrated vignette of a Paris landmark and a short handwritten description in white. The landmarks include the Jardin du Luxembourg, Opera House, Eiffel Tower, the river Seine, the Bois de Vincennes, Notre-Dame de Paris, the Jardin des Tuileries, the Champs-Élysées, Montmartre, and the Luxor Obelisk in the Place de la Concorde. In the centermost two panels is a simple map of Paris showing the landmarks depicted.