Found this note with a bit of historical information:
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Adam Lamont Henderson
Fought in France during WWI. I have his helmet. He was a doughboy and a foot solider and fought in the trenches. He was gassed and wounded. Also have a letter from General Pershing w/ highly collectible autograph and Adam's WWI books.
Found in "Ten Years Near the German Frontier: A Retrospect and a Warning" by Maurice Francis Egan. Published by George Doran, 1919.