The collection begins with Gibson's correspondence. Highlights include an October 20, 1954 letter from the editor of the United States Quarterly Book Review requesting that Gibson read and review Everett Carter's Howells and the Age of Realism, together with a portion of Gibson's manuscript review and the review that was printed in the November 14, 1954 issue of the New York Times. Correspondence also addresses Gibson's editing of William Dean Howell's essay titled "Novel Writing and Novel Reading," which Howells used as his text for a series of lectures in 1899. Rare-book dealers often wrote Gibson with news of Howells works that were available for purchase. For example, John S. Van E. Kohn of Seven Gables Bookshop wrote Gibson on March 6, 1957 regarding a leaflet advertising J.J. Piatt's Poems, with a quote from Howells in Atlantic Monthly that was found in a copy of Little New-World Idyls & Other Poems (1893). The leaflet can also be found in the collection. Gibson's interest in and study of Howells was apparently well-known by his colleagues. For example, Oscar Cargill of Ohio University's Department of English sent Gibson a pamphlet about the Independent Presbyterian Church in Savannah, Georgia that included a comment Howells made on the building in the February 1919 issue of Harper's Magazine. The pamphlet is included in the collection. Various letters, together with the printing specifications of Selected Mark Twain-Howells Letters from Harvard University Press, chronicle Gibson's accomplishments as an author. Other items in the collection include invoices for purchases Gibson made through various book dealers. Annotated lists of works by William Dean Howells track Gibson's collecting efforts, as do a number of catalogues that Gibson used in selecting new acquisitions for his collection. For example, the collection includes a catalogue for the sale of the library of actor and bibliophile Francis Wilson in November 1940. Book collecting practices can also be tracked through advertisements for David Douglas' Series of "American Authors" in one-shilling volumes, which contained several titles by William Dean Howells. Clippings from The Literary World (dating from 1875 to 1878) include references to William Dean Howells and his works. The collection also includes an article titled "The Significance of Henry James," from the January 6, 1927 issue of The Times Literary Supplement. Other clippings found inside Gibson's books include an illustration of "Allies' Day" by Childe Hassam, published in the rotogravure picture section of an unknown publication dating from March 17, 1918. Student papers about William Dean Howells' works can also be found in the collection. For example, papers discuss uses of imagery in Indian Summer and the cyclical nature of time in that book. The collection concludes with newspaper articles from the Hamilton Journal-News and the Columbus Sunday Dispatch Magazine about William Dean Howells and Mac-O-Chee Castle in West Liberty, Ohio, which was built by the Piatt family. John James Piatt (1835-1917) was a friend of William Dean Howells; they collaborated on the 1860 volume titled Poems of Two Friends.