Single-handed sailing – Wikipedia, the free encyclopedia

This use of hand to mean a member of a ship’s crew may derive from the days of sailing ships, where the crew had to work high in the rigging without the benefit of modern safety harnesses; it was an essential precaution that each sailor should hold on with one hand at all times, while working with the other. This meant that each crew member represented one hand for the ship’s work, and gave rise to the saying one hand for yourself, one for the ship. This saying remains excellent advice for sailors today, particularly single-handers.

Single-handed sailing – Wikipedia, the free encyclopedia.

One hand for yourself, one for the ship.