The purpose of the Marine Detachment on the Antietam was two fold. First, it was a highly trained unit ready to go ashore and face the enemy if operations should dictate. Secondly, its' other duties while on board included providing orderlies, acting as messengers, receiving phone calls and taking care of other business for high ranking officers. In addition to these duties they were also in charge of the brig, it's prisoners and manning assigned gun mounts during general quarters.
