- A. Glass Account Book, 1844/18622
- A. H. Hand Papers, 1835/20092
- A. K. Fulton and A. S. Fulton Ledger, 1861/18652
- A. Willis Robertson Papers, 1921/1988, bulk 1946/19663
- A.J. Lawrence Account Book, 1857/18832
- Abigail Brown Shaw Cole diary, 1859/18692
- Abner Johnson Leavenworth Papers, 1825/18612
- Abolitionist Movement Collection, 1834/18882
- Absalom See Account Books, 1854/18693
- Account Book Including Recipes and Home Remedies, 1856/18691
- Account book (N.H.), 1856/18742
- Accounts, 19th Century, 1836/18971
- Adam Empie Papers, 1811/2004, bulk 1811/18502
- Adams Papers, 1782/18902
- Affidavit of Francis Crawford and Margaret Crawford, 1861/18651