- Adin B. Underwood Papers,, 1861/19262
- Administration records collection, 1776/197623
- Admiral John Randolph Tucker Papers, 1865/18975
- Adolphus DeBussey, Soldier, Civil War Letters, 1861/1998, bulk 1861/18712
- Adolphus P. Howard Papers, 1850/19381
- Adolphus P. Howard Papers, 1854/19041
- Advertisement Trade Card for "Quignon-Rombach", 1880/19201
- African American Family Photographs, 1880/19602
- African American Photographic Portraits, 1880/19531
- African American Stereoview Collection, 1860/19011
- African American man tintype portrait, 1865/19001
- African and African American photograph collection, 1850/19451
- Alabama Collection, 1823/18932
- Alan Clarke Railroad Research Papers, 1861/201228
- Alan R. Shirkey photograph collection, 1877/19171