The four monitors in the Fort Fisher attacks were the Canonicus, Monadnock, Mahopac and Saugus and were all surprisingly listed as 3rd Class warships. because of their importance I would have thought they would have been at least 2nd Class if not 1st Class. It was perhaps because of their small number of guns, two apiece except for the double turreted Monadnock.
Canonicus, 3rd class, 2 guns, Off Beaufort, Lt.Cmdr. G.E. Belknap
Monadnock, 3rd Class, 4 guns, Beaufort, NC, Commander E.G. Parrott
Mahopac, 3rd Class, 2 guns, Beaufort, NC, Lt. Cmdr. E.E. Potter
Saugus, 3rd Class, 2 guns, Beaufort, NC, Commander E.R. Colhoun
Evidently, you had to be a lieutenant commander or commander to command one of the monitors. The USS New Ironsides was also an ironclad, but much larger and more guns and rated as 1st Class.
3rd Class? What Gives? --Old B-Runner