The Crosby family papers consist primarily of diaries kept by family members in New Hampshire, Massachusetts, and Michigan. Hale E. and Mary Chamberlain Crosby, who lived in Concord, New Hampshire and later Ashby, Massachusetts, kept a journal recording their work, their religious and social activities. The Crosbys moved with Mary's parents, the Chamberlains, to New Buffalo, Michigan in 1844.

Their son, J. Birney Crosby, was sent from Michigan to Massachusetts in 1860 to attend school. He kept a diary describing his trip east and his school activities, which also gives a good picture of social, economic, and religious activities. Two further volumes record his enlistment in the 12th Michigan Volunteers and his service in the western theater during the Civil War. One of the diaries was kept in shorthand.

A diary kept by John A. Crosby, J. Birney's brother, describes farm work and rural life in New Buffalo, his religious activities, and his attendance at Oberlin College (1870-1871).

Thirteen other small daybooks, kept by Hale Crosby and Birney Crosby between 1890 and 1900, contain brief entries about social activities and farm work in Three Oaks and Berrien County, Michigan.

The collection also contains several receipts and letter fragments, as well as a discharge of mortgage for land owned by Hale Crosby in Berrien County (1883).