Series I. Correspondence consists primarily of business, genealogical, and personal letters received from 1853 to 1890. While only a few letters reflect Joseph's duties as Deputy Collector at the Salem Custom House, a much larger number document his investment in railroad companies and describe the business of the Land Department of the Illinois Central Railroad. Of interest are frequent letters from friends and associates in Denver, St. Louis, Cincinnati, Chicago, and Indianapolis describing the rocketing development of these Midwestern cities. Also of note are letters recounting Joseph's guardianship of his friend Augustus N. Dickens' children received from P. Daggy and the Dickens orphans. The collection contains many letters from family members, especially from Joseph's parents and his brothers, Edward S. and Henry F. Waters. Additional news for Henry's genealogical research in England may be found in letters from John T. Hassam of the New England Historic and Genealogical Society. Letters from Edward often contain Joseph's replies on the same sheet. Although Joseph worked with Nathaniel Hawthorne, there is no documentation of their relationship in this collection.

Letters written by Joseph may be found in the correspondence of his father Joseph Gilbert Waters (MSS 93) and his brother Henry Gilbert Waters (MSS 95).