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. Captain Joseph H. Carpenter was wounded in action on August 9, 1862 at the Battle of Cedar Mountain, and died from the effects of his wound on February 5, 1863 at his parents' home, Fort Carpenter, Virginia. John Cadwalider Carpenter, born in 1839 at Covington, Virginia, served as captain of the battery after his brother Joseph was wounded; he commanded the battery through many engagements, including fifteen major battles, and lost an arm in combat at the Battle of Fisher's Hill, but survived the war.