I’m trying to figure out why I don’t have a SCUBA tank. I was out in the pool before cooling off and realizing, as I do every time I dive under, that one of the great visceral luxuries of the human condition is our unique ability as a land-born species to spend an arbitrary amount of time under water. Swimming is good, snorkeling is better, but SCUBA is really the best. Exotic locales aside, there’s just something about being able to lie flat on your back on the bottom of a pool, let the water get really calm, and stare up at the sky for 10 minutes. It’s meditative in the extreme. This is something you can safely do for about 25 cents worth of SCUBA air if you have the equipment. Weirdly, I have everything to do this except the tank. What’s up with that?