There is none so blind . . .

as he who has been splashed in the face by the sulphuric acid in an exploding wet cell battery. Batteries really do explode (the charging process creates oxygen and hydrogen, the fuel for some rockets), and every year surgeons remove the eyes of people who thought they could blink ahead of an explosion.

A friend of mine, a smoker, once needed light to check the level in his boat battery, so he used his lighter.  His vision survived the blast. A few years later he was sewing a heavy sail on a machine and the needle splintered and pieces pierced his eye. Expensive, but his eye survived that too. Then last year he was incinerating garbage and a Pam aerosol can exploded and the nozzle struck his pupil at high velocity, finishing the job. He can drive, with his head cocked.

Safety glasses are wonderful things, and I keep a pair handy on board. I never but never check battery fluid levels, or wire the batteries, without the glasses on.