There is business correspondence, 1792-1800, with letters from among others Alexander Mackenzie, Joseph Frobisher, Alexander Henry, Simon Fraser and Roderick Mackenzie. There are also minutes and resolutions of the Executors of McTavish in a bound volume; and a contemporary copy of the minutes of the executors of his will, 1805.

The Sir William Osler Collection, distinct from the Bibliotheca, is an extensive archival holding of Osler's correspondence (including eighteen hundred original letters), daybooks, accounts, engagement books, legal documents, book invoices, membership certificates, notebooks, lectures, addresses, newspaper clippings, photographs, books with manuscript additions, and miscellaneous loose items formerly inserted into individual books in his library. The collection also contains various family papers, including correspondence of Lady Grace Revere Osler and Edward Revere Osler.

This collection consists of contemporary copies of letters written by T. Blackwood from Michilimackinac to James and Andrew McGill & Co., to Ch. Chaboillez, and to T. and J. McGregor.

Consists of autograph letter from Charles Burney to Lady Banks, dated 26 March 1808 and written from Chelsea College. The letter is written in brown ink and has remains of wax seal. The letter contains in particular lengthy discussion of the Italian Ariettes of Vincenzo Righini, printed in English in 1791 and muses upon how they managed to arrive in England, their merits, and the poetry of Dryden, Gray, and Pope. Also mentions the music of an "Italianized German of the name of Pfeiffer."

Typed copies of the official and private correspondence, 1814-1821, held in the McCord Museum in the William MacKay Papers. They consist mainly consist of military records such as commissions, 1813-1814, correspondence between members of the British Indian Department, including Lt. Col. Robert McDouall and his description of the siege of Prairie du Chien, with reference to the Omaeqnomenew (Menominee), Hocak (Winnebago), and Meskwaki (Fox) warriors who fought alongside British forces, as well as to the Potawatomi leader Main Poc (referred to as Marpock), 1814-1815 and copies of correspondence of Capt. Thomas Anderson with Lt Col. Robert McDouall on military actions, supplies and Indian relations, 1814-1815. There is also a newspaper clipping about Alexander MacKay and the partnership agreement admitting William MacKay and David Mackenzie into the North West Company in 1796.

The bulk of Girdwood's papers concern his work in forensic medicine. Other materials cover his research in photography, and his general medical and scientific interests. Girdwood's career as medical-legal consultant is documented by 24 cm of his notes and reports, together with some correspondence, on four poisoning trials: People vs Emma Davis (Malone, N.Y., 1881), Queen vs Provencher and Boisclair (Sorel, 1867), Queen vs Joseph Ruel (St. Hyacinthe, 1868), and Queen vs David Prevost and Damase Brunet (L'Orignal, 1881). There are also coroner's autopsy reports and notes for four cases; Girdwood's memoires of ten cases on which he served as consultant; Rogers and Girdwood's submission to the Home Office, London, on the strychnine test, together with letters to Lancet and the Times on the same subject; and notes on the counterfeiting of stamps (1893). His interest in medical photography is reflected in lists of X-rays taken by him (1898-1899) and reprints of three articles. His general scientific and medical activities are represented by a scrapbook of newsclippings on cholera (1854), a lecture on gold presented to the Natural History Society of Montréal (n.d.), essays on strychnine (1864) and water filtration (1869), a review of a textbook in physiology (1864) and some reprints, including convocation addresses to the Medical Faculty. Finally, there is a manuscript copy of an address to the graduating class of Applied Science in 1881 and a small scrapbook of printed articles by Girdwood's father, G.F. Girdwood, M.D.

Consists of letter from Lord Selkirk to Captain Benjamin Walker dated 14 June 1816 concerning the sale of Selkirk’s land at Salmon River, New York, and his impending departure for the Red River.

There are three letters from Lord Selkirk, one from Lord Dalhousie, and eight from Lady Selkirk. The early letters concern the Red River Settlement and the North West Company. The letter from Lord Dalhousie, 1824, concerns legal matters, and the two late letters, 1828 and 1833, from Lady Selkirk are personal in nature.