Classification of Jobs
It was 1885 before the system of "job families" of the type in use today was devised for enlisted personnel. The next year a scale of pay grades extending from Third Class Seaman to First Class Petty Officer was adopted. Enlisted personnel were grouped into three general classes according to the type of work done; seaman, special, and artificer. The relatively few ratings of the day included Engineer Force Petty Officer, Ship's Corporal or Master at Arms (at that time the only petty officer with chief status), Schoolmaster, Sailmaker's Mate, and Apothecary.
Information Courtesy of Naval Historical Center