The collection contains correspondence, diaries, articles and addresses written by Darling, a subject file, personal financial materials, news clippings, photographs, and engineering plans.

While surveying the collections of the NEMHC for the Minnesota Radicalism project, these items were identified as potentially useful for labor development research. Additional materials will be added to this collection as they are donated and appropriate.

The collection consists of eight items concerning the Aerial Bridge and Thomas McGilvray.

The collection contains personal and financial correspondence, letterpress books, scrapbooks, newspaper clippings, manuscripts written about local and family history, financial records, legal papers, maps, photographs, one audio cassette of an interview, and reference materials.

The collection contains correspondence and biographical information, 1869–1900; news clippings concerning George Sargent, 1931–1941; photographs including a portrait of Sargent and an image of his house, 1869–1965; and one scrapbook containing personal correspondence concerning Sargent's life, work, and speeches, news clippings, and some maps, 1851–1875.

The collection contains letters to Truelsen's daughter and business letters, 1816–1932 and two scrapbooks containing news clippings covering Truelsen's term as mayor of Duluth, Minnesota, 1896–1902.

The collection contains news clippings concerning Wieland's work in history and his life, 1932–1972; business and personal letters, 1939-1946; typed copies of papers written by Wieland, 1935–1942; and a published pamphlet by Wieland, Americanism and World Peace,1925.