- Abraham Lincoln Collection, 1860/19651
- Absalom See Account Books, 1854/18693
- Account Book Including Recipes and Home Remedies, 1856/18691
- Account Books, 1782/18953
- Account book (N.H.), 1856/18742
- Accounts, 19th Century, 1836/18971
- Achilles Dew, Letter to President Lincoln, 18611
- Ackerly Family Papers4
- Adalbert J. Volck Collection of Etchings, 1861/19791
- Adam Empie Papers, 1811/2004, bulk 1811/18502
- Adam W. Johnson, Soldier, Letter, 18611
- Adams Papers, 1782/18902
- Adele Goodman Clark papers, 1849/19784
- Adin B. Underwood Papers, 1861/19263
- Administration records collection, 1776/197611