Correspondence 1921-1931 concerning Simon McTavish; official copies of legal documents including estate inventories, lawsuits over the McTavish estate, and Simon McTavish’s will; notes for Baylis’ study of McTavish; numerous petitions and newspaper clippings on the state of the McTavish monument and tomb (Peel St., Montreal), and a typescript of his text concerning Simon McTavish. Also two letters from Ignatius Donnelly, 1899, and a letter 1895, from J. Middleton to John Doyle about 19th century gardening in Montreal and the funeral of Judge James Reid.

About half of Donald's papers consist of diaries giving brief daily records of his professional and sometimes personal activities from 1918 to 1981. The remaining files fall into two series. Essays and addresses, 1919-1962, largely on economic aspects of the chemical industry, were addressed to professional organizations and commercial bodies such as the Engineering Institute of Canada, the Canadian Chemical Association, the Canadian Chamber of Commerce, and the Industrial Development Board of Manitoba. More informal speeches include a radio talk on jobs in the chemical industry, 1938. Personal materials comprise some family, legal and investment records, 1940-1952, and undergraduate essay on medieval universities, 1910, correspondence related to an annuity fund set up by Donald for Jessie Henderson, secretary and librarian of McGill's Chemistry Department (1946-1961), and a file of press releases and congratulatory letters on Donald's receipt of the Chemical Industry Medal, 1952-1953.

The administrative records constitute the bulk of the collection; they include annual reports, and financial statements of John Millen & Co. and related firms, 1962-1972; quarter-monthly reports, 1956-1969; memoranda, 1961-1969; files concerning clients, products, sales, and inventory, 1960-1969; executive meetings, 1960; staff lists, 1955-1970; budgets, 1965; files on Exide & Oil Co. Sales, 1964-1968; file on Modern Sales Ltd., 1943-1970 and business correspondence, 1943-1972. Legal records consist of leases, 1963-1964; employee contract between S.B. Millen and John Millen & Son Ltd., 1968; correspondence, memoranda, and court cases, ca 1930-1936. Also included are reports and typescripts on the principles of management and sales, 1948, 1960-1969, as well as some newspaper clippings.