My old climbing gym occupied a cavernous warehouse space with powerful lights, the kind that take 15 minutes to warm up, but when they do it feels like the sun moved a few million miles closer to Earth. The building was a monstrous rectangle with few window, it looked as if the architect had been inspired by a refrigerator box. As such, there was no breeze. You'd pull your hand out of your chalk bag and any of that fine particulate that did not stick your hands would float up into the air to hover in a hazy cloud with the everyone else's chalk. If a study's been conducted on the hazards of breathing chalk dust, I've never seen it, but I worry that one day all of these sinewy athletes are going to come down with the gym climber's version of black lung. We'll tell our kids "We didn't know any better!" and they'll think that everyone back then must have been morons.