Strong copper chains connected with the aft side of the rudder by a span clamp and shackles. They are about 6 feet in length; a hempen pendant is then spliced into the outer link, and allowing for slack to permit the rudder free motion, they are stopped to eye-bolts along the stern-moulding, terminating on the fore-side of the stools of the quarter galleries. They are, when the rudder or tiller is damaged, worked by tackles hooked to the after-channel bolts. But their principal use in later times is to save the rudder if unshipped by striking on a reef or shoal.