1813 February 2. Sylvester Day ADS to U.S. Senate and House of Representatives; s.l.
Petition of Sylvester Day for the loss of property following seizure by Lieutenant Elliot.
1813 March 13. Thomas H. Cushing ALS to Sylvester Day; Washington, D.C.
Cushing requests that Day travel to Philadelphia and present himself to Colonel George Izard.
1813 April 20. William Duane ALS to Sylvester Day; Philadelphia, Pennsylvania.
Duane, as acting adjutant general, informs Day that "officers on parole are precluded from all duties of public nature, you are authorised to move to your usual residence, and report to the Adjutant General."
1815 January 24. George Izard ALS to Sylvester Day; Batavia, New York.
Relays orders to continue working at the hospital unless ordered otherwise by the Secretary of War or the general commanding the ninth military district.
1816 February 17. [Alexander] Macomb ALS to Sylvester Day; Detroit, Michigan.
Requests medical aid for Mrs. Macomb or, failing personal attention, a referral to a doctor that can help her.
1816 March 8. [Charles?] Larrabee LS; Detroit, Michigan.
Account of Day's actions and possessions following the surrender of Detroit in 1812.
1817 October 17. Sylvester Day ALS to Hannibal Day; Detroit, Michigan.
Letter to his son, Hannibal, urging him to keep up with his studies and asking when he will next be at home.
1818 January 3. [Lewis Cass] AN to Sylvester Day; Detroit, Michigan.
Invitation for Day to attend dinner with Michigan Territory Governor Lewis Cass.
1818 March 27. Sylvester Day ALS to Hannibal Day; Washington, D.C.
Sylvester expresses his pleasure with Hannibal's studies and speaks of the next time he will be in Albany, New York.
1829 May 6. E. Kirby ALS to Sylvester Day; [B'ville?].
Political letter: "Van Buren has deserted & gone to the devil & your money with him."
1835 January 6. David Beard DS; s.l.
David Beard's testimony for Day's property claims against the United States; provides information about Day's actions following the British seizure of Detroit.
1850 July 12. Document to Sylvester Day; s.l.
Official certificate acknowledging that Day donated five dollars for the building of the Washington Monument and his membership in the Washington National Monument Society.
1896 January 24. George D. Ruggles TLS to George S. Greene; Washington, D.C.
This item is a brief letter from the adjutant general of the United States, and outlines the dates of Day's various military appointments.
1896 May 14. George D. Ruggles TDS; Washington, D.C.
Outlines the dates and locations of Day's various military appointments and posts.
1920 November 26. Merritte Weber Ireland TLS to Lavinia Day Hoff; Washington, D.C.
Provides a listing of Day's documents in the possession of Ireland, then surgeon general of the United States Army.
Undated. D. A. Hall ADS; s.l.
Official memorial of Sylvester Day - details the circumstances leading up to his detainment and loss of property after the surrender of Detroit.
Undated. Document; s.l.
The "Sources in the Revolution of Doctor Elkanah Day of Westminster, Vermont & his descendents" is a miscellaneous collection related to Elkanah Day and his heirs, taken from Peter Force's "American Archives" series, Volume 1.