why pirates were smart

my friend was telling me about a mythbuster show he watched the other day on pirates... with such intriguing topics as why the sliding-down-a-sail-with-your-knife-bit doesn't work. but one thing that was interesting was about the eye patches. pirates did indeed wear them, and with good reason. when on deck, they would keep a patch over one eye, so that when they went below deck they could switch the patch and have an eye that was already adjusted to the darkness. they could see immediately. brilliant! they tested this and found that without an eye patch it took people up to 30 minutes to fully adjust to the light difference. which is huge when yer under seige and need ta fire an 18 pounder. arrrr :)