A lifebuoy has become the back of a chair.
"The Admirable Crichton"
J. M. Barrie
Then a lady ventured into the sling-lifebuoy, or cradle, with a sailor, but they stuck fast during the transit, and while being hauled back to the wreck, fell out and were drowned.
"Battles with the Sea"
R.M. Ballantyne
Thus the whip becomes a double line-a sort of continuous rope, or, as it is called, an "endless fall," by means of which the lifebuoy is passed to and fro between the wreck and shore.
"Battles with the Sea"
R.M. Ballantyne