
1864. "James River, Virginia. Double-turreted monitor U.S.S. Onondaga; soldiers in rowboat." From photographs of the Federal Navy and seaborne expeditions against the Atlantic Coast of the Confederacy, 1861-1865. View full size.
That was a tough way to earn your three squares a day.
I've always been amazed at how little the Monitor-class ships rose above the waterline; it is evident that the design was meant for calm, protected coastal waters where the small overboard height would make it difficult to landlocked artillery to aim efficiently to the ships. The problem with this design, as demonstrated by the loss of the U.S.S. Monitor, is that in rough waters they were very prone to being swamped.
Must have been really claustrophobic below deck!