Approximately half this material consists of letters, covering the years 1823-1837, from Andrew William Cochran, 1792-1849, civil secretary to the governors of Lower Canada from 1812 onwards, and a member of the Executive Council from 1827 to 1841. The remainder comprises a number of accounts of travels and exploration by North West Company employees, probably collected by McKenzie for his history. Included are Charles McKenzie's expeditions amongst the Otoe Missouria Tribe.; Edward Umfreville's journal of a canoe trip from Lake Superior to Portage de l'Isle 1784; accounts of the Alaskan Athabaskans, 1795 and 1805, George Keith's memoirs of the McKenzie River Department, 1807-1817; and George Henry Monk's of the Department of Fond du Lac or Mississippi, 1807; John McDonnell's account of the Red River, ca 1787; and John Johnston's of Lake Superior and a letter on the Indigenous communities of the northwest from Eneas McDonnell. Also included are letters written to McKenzie from Forks on the Mackenzie River by William Ferdinand Wentzel, 1807-1824.

Fonds contains "The journal of an English lady; or letters descriptive of the continent during the years 1829 and 1830" to which have been added water-colour illustrations by the author.