Pirate eye patch Bashny.Net

There is a theory that pirates and other sailors wore a bandage on the eye for purely practical reasons. The fact that the hold of the ship's very dark, and the descent to the deck of the human eye takes a few minutes to adjust. If a sailor wearing a blindfold, he could take it off in the hold, and immediately see well with one eye - this greatly increased the efficiency of its work in dangerous moments, especially in battle. While confirming its historical data does not exist, version looks credible and has been verified by tests in our time. Documented a similar use of the bandage at the dawn of the pilots of airplanes as they flew over brightly lit cities: one eye they can look outside, and others are exempt from the bandages on the cards and devices in the dim cabin.

Source: muzey-factov.ru/tag/sailing