This subseries contains the autographs of literary figures (including Goethe, Lydia Huntley Sigourney, Harriet Martineau, John Clare the "mad poet," Lord Bulwer Lytton, Thomas Ward, Richard Henry Dana, James Russell Lowell, James Paulding, Robert Louis Stevenson, Sarah Orne Jewett); editors and historians (Jared Sparks, Evert A. Duyckinck, George Bancroft, James Grant Wilson); statesmen and politicians (Henry Clay, Daniel Webster, Hamilton Fish, Theodore Roosevelt, Marquis de Lafayette); clergy; artists and architects (William J. Hennessey, Frederick Cozzens, John Rogers, Elisha Magoon, William Wetmore Story, John LaFarge, Chester Harding); theatrical and musical figures (Charles Kean, Ignace Jan Paderewski, Josef Hoffman); scientists and medical men; some military leaders; and some British peers.

The autograph collection includes passports, commissions, instructions, correspondence, vouchers for book purchases for the State Department, and letters connected with Dwight's mission to secure the Stevens' Franklin Papers (papers of Benjamin Franklin) in 1881 in London and the Rochambeau papers in France. These papers document Dwight's private and official negotiations with Henry and Benjamin Franklin Stevens. Initial feelers seem to date from 1876, and Dwight's correspondence with the Stevens family also mentions the 1877 Caxton exhibit, the Clinton collection (1884-1888), a scheme to search out American letters (1772-1784) in Europe (1885), book purchases for the State Department, and personal subjects. There is an extensive correspondence with Edward C. Bigmore (1878-1887), the agent for Stevens' American Library and Literary Agency in London, covering literary, bibliographical, documentary and personal matters. Also included from this period are papers relative to Congressional committee work on the requisition of funds for the purchase of the Franklin Collection, accomplished in 1882 by the U.S. Government.

The earliest item in the collection is a payment order signed by the Duke of Albemarle in 1668. Located at the end of the alphabetical autograph series is an unidentified Icelandic sermon, dating from 1771, that was given by George Stephens to Dr. Emil Bessels, who presented it to Dwight.

For a complete list of individual items in the autograph collection, see Items in the Autograph Collection below.

This subseries contains letters to Henry Adams, written between 1861 and 1866, including a few written to Marian (Hooper) Adams ("Clover"). Adams' chief correspondents were George Bancroft, John Hay, Baron Houghton, Henry James, Clarence King, Francis T. Palgrave, H. H. Richardson, and Thomas Woolner, among many others.

For a complete list of individual letters in this subseries, see Items in the Henry Adams Letters below.

This subseries consists of a few early Dwight family letters and documents dating between 1791 and 1822.

This subseries consists of letters written by Dwight to his friend William Baker between 1864 and 1875 from Auburn, N.Y. (1864-1867) and other points in N.Y. (to July 1868); from the steamer Arizona (Aug. 1868); from San Francisco (Sep. 1868 to Nov. 1872); from G.P. Putnam's Sons (1873); and from New York City and Washington, D.C. (1874-1875). The letters are mainly concerned with autograph collecting, but also provide detailed descriptions of Dwight's life in San Francisco.

This subseries consists of miscellaneous papers, dating approximately from the 1840s to the 1880s. Included are notes on autographs and coin collecting, art and artists; a draft of a paper (apparently by Dwight) on Mendelssohn; unidentified essays and book chapters, notes, etc.; unidentified pencil and ink sketches; newspaper clippings and miscellaneous printed matter.