My buddy and I were sitting about 400 yards into JaR cave near Mt. Adams middday. We were taking a break from climbing over the big break down boulders. The cave is one in a series of long lava tubes from a flow several thousand years back. We turned off our flashlights to conserve, as light was unnecessary for communication. About 7 minutes into the break, I notice a dimly flickering light downhole about 70 feet or so. The rough lava really sucks up the lumens, and the light was initially so dim I thought my eyes were maybe a little screwball, so I asked my buddy if he could see it. After a moment, he confirmed it wasn't just me, so we wondered if maybe someone else was in the cave ahead of us and coming back our way. We sat and watched the light flicker and dance on the walls of the cave, noting that it didn't seem to be getting any closer or farther from us, nor changing in average intensity. After a couple minutes of this, we decided to hail the other spelunkers, and shouted out a greeting, but got no response. We did it again, and the light went out. We decided someone was playing around with us, so we turned on our flashlights and proceeded down the cave.

After about 10 minutes, we'd traveled another couple hundred yards or so, and encountered no one, nor found any sign of any other activity. We decided to turn off our lights and sit in the dark again and see if we could detect the light. As we sat there in the dark, looking ahead of us, we saw nothing. I turned back to my friend, and noticed a faint flutter of light over his shoulder. It was the same sort of light we saw before, but now it was behind us. I told him to look to confirm, and when he did, we both got real quiet. The light was a dim yellow, and danced like a candle flame in a gentle breeze. We were perplexed.

We decided to creep back to the light in the dark, which is not easy because you can't see where you are going and the breakdown is as bad as jetty rock, so it is slow going. As soon as we started back out the cave, the light quit. We stopped and waited for about 15 minutes, but the light did not return. We turned on our lights and proceeded to where we figured the light was, and sat with our lights off again, but no more light returned.

What you have to understand about these caves is that they are a very sterile environment. Basically it is a hollow lava tube 40 feet or so under the ground running more or less in parallel with the surface. The temperature is around 40 degrees, and the humidity is saturated, with water almost continously dripping from the roof. The mineral content of the soil is very poor, so leaching is practically non-existent, except for the occasional silica nodules hanging an inch or so down off the roof. Bats will occupy space near the threshold where outside atmosphere penetrates enough, but past 50 feet or so, nothing dwells in there, no plants, no animals, no insects. No one we've talked to in the grotto (a spelunking group or club in the region) has ever seen any sign of life beyond the threshold area, and certainly nothing that self luminates. Likewise, our examination of the area in the cave where we felt the lightsource must have been revealed nothing that would lead us to believe an ambient light source was present.

We never saw the flickering light in that or any other cave in the system since then, though we've been downhole dozens of times. We concluded that whatever made that light wasn't something you would expect to find in the cave, and never returned.