I took a break from work today to drive down to White Rock with Broxton, who had just recently arrived in town. We had been talking back at MIT about places we had been around here and he mentioned that when he was a kid growing up in White Rock, he remembered finding some little lava tubes in Pajarito canyon.

We parked the car near the canyon and hiked down into it and along its length looking for said tubes. Predictably, they were much smaller than he remembered them. We found a few little lava caves, less than two meters in diameter and going back not more than three meters.

But the last one we came across was interesting, not only because it was the largest, but because there was a huge amount of very cold air rushing out of it. This is indicitive of a very large underground space. The constant subterrainian temperature creates a pressure difference and causes large caves to "breath." The larger the volume of the cave and greater the temperature difference between the cave and the outside air, the more it breaths.

This cave was breathing enough that when we walked by it in the center of the canyon about five meters away, we felt a cold blast of air. Investigating the innards of the cave, we found a 1.5m entrance hole and a space that went back and down about 4m. There was one side cavity that went steeply upwards and dead-ended. At the very back of the lowest part, the wind was coming up through the rubble that constituted the floor.

The rocks are lava rocks - not very heavy, relatively small, and easy to break with tools. Clearly, someone had discovered this cave breath before and had begun excavating; there was a large amount of lava rock debris strewn around the canyon outside the entrance.

The one creepy thing about this mini-cave is that there were black widow webs in it. We couldn't find any spiders; the webs looked old. I did, however, read up on treating spider bites when I got home. Turns out widow (and brown recluse) bites aren't usually deadly like I thought they were; they just mess you up. And antidotes are available. Good to know.

This whole "lots of wind from a small cave" story sounds a lot like Lecheguillia. Just because it's exciting and because we have no sense of probabilities, Mike and I are going to go back with gloves and try hauling out more rubble.