The series consists of business and legal documents, correspondence, addresses and memoranda, and newspapers. Many of the legal and business documents are concerned with insolvency cases in Montreal, 1841-1875. While most of the material relates to Brown's political activities and business in Canada, some letters relate to the United States, particularly Florida, and its expulsion of Native peoples. The series includes an index of the Vindicator, 4 Nov. 1836 to 7 Nov. 1837, as well as a journal Brown kept aboard the Mary Frances during a sea voyage in 1838.

Series consists of three scrapbooks. The scrapbooks contain notes, patient prescription information, reprints of various publications by MacDonnell, and lots of news clippings concerning various topics such as the history of Montreal, McGill University, the McGill faculty, Montreal General Hospital, and obituary notices

1889: 4 letters
1890: 10 letters
1891: 8 letters
1893: 4 letters

The series consists primarily of incoming correspondence to various administrative units of the Natural History Society. This includes letters to the Recording Secretary, the Corresponding Secretary, the Chairman, the Librarian (dealing largely with book binding costs), the Chairman, the Editor of the Canadian Record of Science (primarily acknowledging receipt of the journal), and the Museum Curator. While most of the series consists of loose documents, it also contains two “Letter Books,” which have indexes of whom letters were sent by or to. These letters are highly administrative in nature, dealing with the daily operations of the Society and not the personal correspondence of its members.

The letters have substantial gaps between 1872-1878, 1881-1884, and in 1895. Many of the loose letters were donated to the Blacker-Wood Collection bundled together and they have been preserved together. However, many of the other loose letters were sorted by year by the archivist or librarian who originally processed them.

Notable Natural History Society members and other prominent people in these files include:
J.F. Whiteaves (non-member)
The Governor General of Canada (non-member)
David R. McCord (non-member)
Sir John William Dawson, as President
Professor David P. Penhallow, as Committee Chairman
Charles Robb, Librarian
E. J. Chambers, Librarian
R. Lachlan, Secretary

The series consists of 20 maps produced by Meteorological Service, Dominion of Canada, showing only southern Canada. Each map depicts the average temperatures and precipitation for the month across the country. For the year 1886, there are several duplicates of some months. The years of 1895 and 1897 are incomplete.

This series includes John William Dawson's papers, which are chiefly scientific and scholarly in character, with some materials reflecting other aspects of Dawson's career, particularly educational work and religious controversy.

This series contains correspondence between members of the Hall family and their extended family members from approximately 1742 to 1899. Letters were written predominately from New England (especially Philadelphia and Andover), Quebec City, and Montreal. The contents of the letters chiefly concern family news (including deaths and births), with some letters related to business, political and military events, and genealogy.

The correspondence in the series is grouped into a file for each family member represented - usually the creation of the letters, though some files also contain letters they received. There is also a file of correspondence related to family legacies and genealogy, as well as a file of miscellaneous letters, created by senders who were unidentified or who only appeared once in this series. The files in this series are arranged in approximate chronological order.

Series consists of theatrical portraits and coloured printed scenes, including some published by J. Redington and Épinal.

The Montreal Mendelssohn Choir donated eight volumes of choral sheet music from the Choir’s library in 1895, a year after the Choir’s dissolution. There are only seven extant volumes in the collection because volume 6 has been missing since at least the 1980s.

Three volumes of choral sheet music from the Choir’s library were donated to McGill University by the Estate of D. Torrance Fraser, a former choir member, in 1926. The pieces in these three volumes are second copies of those pieces found in Series 1. In 1927, another volume of sheet music from the Choir’s library was donated to McGill University by the Estate of D. Torrance Fraser. This fourth volume (DTF2) contains many pieces not found in the other volumes.