This commonplace book was filmed exactly as bound and contains notes on medicine, diseases, and weather; poems by Erasmus Darwin and others; family genealogy; letters; and sketches. There are notes by other family members, including his wife, his daughter, and his brother. There is a letter to "Major Darwin" dated 1929 taped inside the front cover, recounting the provenance of the book.

This diary records the weather and appearances of birds, flowers, and insects.

These papers include correspondence, itineraries, literary diaries, meteorological journals, sermons, and miscellaneous papers.

This printed account includes a list of trees and shrubs, a catalog of vegetables and the time of their flowering, and a list of animals and minerals found in the vicinity of the Red River, as well as meteorological observations.

These are letters to Quetelet primarily on the subject of astronomy (meteorological observations), including charts showing directions of shooting stars.

The manuscripts of father William Mitchell and daughter Maria Mitchell are not easily separated, and are treated here together. The collection includes William Mitchell's autobiography, his memoir of Judge Walter Folger of Nantucket, astronomical and meteorological observations, lectures, family and other correspondence.