Series III. Other Research/Topics of Interest contains material about other research areas that Adney had an interest in. This material includes notes, manuscripts, sketches, photographs, news clippings, and has been divided into seven subseries. Subseries A. Canoes contains materials relating to Adney's study of birch bark canoes, including research notes, sketches, and photographs. Subseries B. Heraldic Art contains research notes, sketches, and drawings of heraldry and crests. Subseries C. Treaties/Political Status of First Nations contains material relating to various treaties involving First Nations, and the political status and rights of the people of the various tribes. Adney was an advocate for the fair treatment of the First Nations, and lobbied on their behalf at numerous times. Subseries D. Mythology, Astronomy, and Natural History contains material researched and collected by Adney about First Nations' mythology, astronomy, and natural history. This subseries contains notes, research material, drawings, and photographs. Of interest is a sample that Adney collected of a fern, known as a Fiddlehead (box 30, folder 1). Subseries E. Ethnology contains research, notes and sketches about the characteristics of the various tribes that Adney studied. Of particular interest in this subseries is a volume of sketches of "picture writing" found at Lake Missinaibi, Ontario.

Subseries F. Norse Correlations contains materials relating to the idea of correlations between the First Nations and Norsemen, and the Norsemen's travels to North America. Subseries G. Animals and Trapping contains materials relating to Adney's study of animals and their relationship to the First Nations. This subseries also contains material about the trapping of animals and the fur trade. Subseries H. Tobacco contains research notes, photographs, and samples of tobacco. Subseries I. Notebooks and Miscellaneous Research contains Adney's notebooks, research notes on miscellaneous topics including other people's publications with Adney's notes, and news clippings on various topics. Included in this subseries are some news articles written by Adney.