Shortly after the end of the Second World War, a German man visited his eye doctor complaining of “floaters” — little specks drifting around in his field of vision. As anyone today can verify by googling the term, it’s an extremely common condition. It’s almost always benign. Eye doctors see this all the time.
What this doctor saw, however, when he peered into the patient’s eye, was by no means ordinary. Floating within the eyeball, slowly tumbling end over end, were rods of a metallic substance — copper — each about a millimeter long.
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There was an obvious common link among all of these men with copper rods in their eyes: they were all truck drivers. Further interviews began to shed some light on their histories. During the last years of the war, Germany—formerly one of the most industrialized and motorized countries in the world—had run desperately low on fuel. There were still many vehicles on the roads in good working order, but they couldn’t move, simply because there was no fuel to put in their tanks. And yet goods still had to move from place to place in order to keep the economy going and the war engine running. In desperation, truck drivers had turned the clock back a few decades and reverted to the practice of using livestock to pull their vehicles down the roads.
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Some ingenious driver somewhere in Germany figured out that if you stripped a length of such copper braid from a collapsed building and cut it to length, it would work just fine as a whip. Actually getting the thing to crack required a bit of practice, of course. These guys didn’t have the benefit of professional trainers telling them how to do it right.
A common mistake among novice whip cracking practitioners is to yank the handle of the whip toward you in order to accentuate the crack. This actually works. But it’s discouraged on safety grounds. When you do it, the end of the whip tends to snap back toward you. Experienced whip crackers don’t do it that way.
Putting two and two together, Dr. Erggelet asked these drivers whether, while cracking their makeshift copper whips, they’d ever felt a sudden sharp sting in the eye. The patients answered that this was certainly the case, but that in a few minutes the pain went away and they thought nothing more of it.
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