Two other 3rd Great Grandfather's, Gilbert Jesse and Joseph Rock, also served in the Civil War. Gilbert Jesse mustered in at Plattsburgh on the 14th of September, 1864. His widow, Catherine "Kate" Jesse later filed for a widow's pension after he passed (after serving):
About a week earlier, on September 5, 1864, Joseph Rock mustered in as a Private, Company L, New York Volunteers:
Details of how a musket from his service managed to get separated from the military and end up in the hands of other ancestors is detailed here.