Transcriptions of many of the earliest letters appear, both in separate folders and interfiled with the original correspondence. The bulk of the materials are not organized chronologically and it is not uncommon, particularly in folders of clippings and photographs, to find materials that span the 19th and 20th centuries in a single folder. In the 20th-century correspondence, there are interfiled letters in response to reference questions relating to the archival materials themselves. The collection was processed by Barbara J. Burke, ca. 1977, and it has been largely left in the order she imposed. The materials are loosely organized by type, with the earlier correspondence preceding printed matter, followed by photographs and illustrations.
Memorabilia round s out the collection.
Within each material type, documents are frequently grouped by subject. Twentieth-century correspondence and materials relating to the maintenance of the museum and the archival collection appear at random intervals. An item level listing of letters authored by P.T. Barnum exists. He held a series of diverse jobs as a youth, including selling theater tickets. He then became head of a traveling company of performers, acrobats, freaks, and wild animals.