The collection consists of 18 series: Correspondences, Business Records, Certificates, Charts, Circulars, Diaries, Legal Records, Magazine and Journal Articles, Manuscripts, Maps, Memoranda, Meteorology Records, Notes, Papers, Speeches, Telegrams, Miscellanous and Portraits.

The correspondences, diaries, meteorology records, notes, and speeches pertain to his Oregon trip. Correspondences are valuable in providing description of the territory, battle with the Blackfeet Indians, and Fort Vancouver. There are also correspondences regarding his family, friends, education, Grand Rapids and Michigan, politics, the Mexican War, and Indians. Business Records detail land speculation and law practice.