Armour, teak backing, and a low fighting profile

Protection varied by location, with six to eight inches of iron backed by nine to eleven inches of teak. The breastwork carried eight to nine inches, while the turret faces had ten inches and the sides nine. This early armour plate was not yet the armour steel developed in later decades, and an armoured deck protected the fighting core from above. Water admitted to the ballast tanks reduced the already low freeboard until only the turrets and breastwork remained exposed. In shallow harbour water she might even touch bottom, but the lowered profile made a difficult target and turned the ship into something close to a mobile fort.