A military hat called a “Chapeau-bras”—French for a folding hat that can be carried under the arm—which was worn by New York State Militia officer Jacob DeForest when he was the inspector of the Militia’s 11th Brigade before the Civil War. He later went on to serve as a Colonel in the 81st New York Volunteer Infantry, a regiment from Oswego, during the Civil War. This is typical of pre-Civil War militia uniforms.
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