 Among the original members of the company were Joseph's brothers John Cadwalider Carpenter and Samuel Steuben Carpenter.The brothers played a central role in the unit's wartime service.When the company's commissioned officers were reorganized after the First Battle of Manassas, Joseph H. Carpenter became the captain of the battery with John C. Carpenter as his first lieutenant; in a later reorganization John C. Carpenter became the captain of the battery with Samuel S. Carpenter as his second lieutenant.