Book review: Blind Descent

Authored by James M. Tabor in 2010 (ISBN 978-1-4000-6767-1).

The author relates the multiple expeditions of two leaders in the field: Bill Stone, Ph.D. and Alexander Klimchouk, Ph.D.

Dr. Stone focused his efforts on the Cheve cave in Mexico, where he and his team pushed down to -4,869 feet, making it the 9th-deepest in the world. Klimchouk's team descending to -6,825 feet in Krubera cave in the Caucasus mountains, making it the deepest. For both the starting point was well above sea level, so the caves do not descend below sea level. Team is a key word in the sentence above; professional caving expeditions involve dozens of participants and tons of gear. "Professional" caving is not lucrative in the sense of other, high-profile professions. It is a profession for these two spelunkers, though, because of the large sums of money involved, which these leaders spend much of their time raising. The leader must also secure permission from local authorities. Given the two expeditions from this book occur in Mexico and the former Soviet state of Georgia, political entities without a long history of respect for law, obtaining and keeping permission is not trivial. Stone faced the extra hurdle of local residents who viewed the cave as a religious emblem and disliked his operations there.

Tabor's description of caving was much different than my lay understanding. When I thought of caves I thought of stalagmites rising from the ground and stalactites descending from the ceiling. Those are present in limestone caves, which these are not. The key description is dark, pitch black. Darkness, experienced for up to two weeks at a time for some members, causes depression and suppresses the immune system. Carbide lamps were typical light sources, being replaced (but not exclusively) by LEDs. Next is wet. Caves are formed by the flow of water and the spelunkers are always wet because they are operating in flowing water that ranges from a trickle to a waterfall. At other times they are pushing through sumps: pockets of water that separate two airspaces in a cave. The only way to get from the air space you are in to the air space you want to be is to pass through this water.

Next is grueling and dangerous: think mountaineering in reverse. Cheve descended nearly 5,000 vertical feet, Krubera more than that. Rock climbing with ropes is the essential mode of transportation. The reverse-climbers plan stages and cache them with food. Falls and death are, if not common, part of the job. And, while mountaineers face thin air and cavers generally have plenty of oxygen, cavers face at least three additional difficulties. First, mountaineers do not have to dig. Cavers often dig in tight spaces (hence the need to dig at all). And, the material dug out needs to be carried up to be removed. Using an average density of rock at ten times that of water, a one-gallon container weighs 85 pounds. Second, rescue is especially tricky in a cave. Whereas the climber may have contorted his (usually his, though the book did mention a few women cavers) body to slip through a narrow passage, a metal litter used to recover an injured caver cannot so bend. Now, combine that complication with the fact that the rescue involves the hard work of lifting a heavy body and rescue litter thousands of feet. And, helicopters can be used to evacuate an injured mountaineer but not an injured caver (at least until the caver reaches ground level). Third, mountaineers rarely run the risk of drowning. Recall the water and imagine a caver crawling through a space that is only a few feet high. A strong rain from above can quickly raise the water level below by several feet. A caver caught in a narrow passage can find his air replaced by water and drown.

Like mountaineers, spelunkers must also deal with wind. This surprised me. The deepest caves have an outlet at the bottom as well as an opening at the top. Tabor describes Stone as pouring dye into the water at the top of Cheve and having a team member observe the dye in a nearby river, 8,000 feet below. The outlet allows more water to flow through and widens the cave, deeper, making the cave easier to descend. This wind produces much noise and, combined with the wetness, interferes with sleeping. Also interfering with sleeping is the lack of flat surfaces. Caves have less space than mountains and finding that cozy-little-spot is near impossible. Beds are sometimes narrow trays bolted to the rock above a rushing waterfall.

Krubera cave was more cramped that Cheve, but Cheve had far more water. Its spelunkers needed to traverse long sumps, longer than one could hold his breath. Stone was an engineer by training and he spent years developing an advanced scuba tank called a rebreather. Tabor, at least, describes it as a Stone invention. The wikipedia article does not mention Stone. The idea is clever: we inhale oxygen and exhale carbon dioxide, except that is not quite true. We exhale carbon dioxide and oxygen; our bodies do not make use of all the oxygen we inhale. Rebreathers capture this oxygen and last approximately ten times longer than a standard tank, depending on the depth of the water. The rebreather does not expel gas, a further advantage in military applications where the user does not want to be detected.