Certificate of promotion issued by United States Army for Hamilton Coolidge, October 3, 1918. Certifies Coolidge's promotion to Captain in the United States Army.
Certificate of honorable discharge for Hamilton Coolidge, October 3, 1917. Certifies his release from the Reserve Corps so he could take a commission with the Allied Expeditionary Force. Includes Coolidge's enlistment record. Two pages.
Letter to Hamilton Coolidge from Douglas Campbell, May 20, 1918. Describes some of the recent air battles that Campbell was involved in while flying with the 94th Aero Squadron at the front. Includes typed transcription. Three handwritten pages and…
Telegram to Lieutenant Hamilton Coolidge from his brother, J. H. Coolidge Jr., June 18, 1918. Send greetings from his brother John Gardner and sister Mary Eliza, via their parents.