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Into the Black Water A L A N C H R I S T I A N A N D J O H N H A R R I S “IT WAS A DARK and stormy night!” is the feeling experienced by every black-water river diver as he or she begins a descent, at least the ones who survive to become knowledgeable enough to tell the tales. If a diver doesn’t have the jitters before a dive, especially a dive at depth, then trouble looms in the darkness. Ah, the darkness! It is so absolute, engulfing , mind-warping, and, well, sometimes terrifying. The descent begins with the “all’s well” thumbs up to the dive tender and observers safely planted in the dive boat enjoying the breeze, sunshine, wispy clouds, and the security of a copious air supply. The adage “You don’t know what you’re missing until you’ve been forced to be without it” doesn’t do justice to being deprived of air. What is more free than air? Have you ever been without, even just for a minute? Have you ever been forced to be without, to yearn for that next breath, to have lungs and diaphragm that pull from within and receive nothing in return but the burn of deprivation? The panic that can arise from air deprivation can be overwhelming and lethal for the inexperienced diver. Why Black-Water Dive? The reason I, Alan Christian, got involved in black-water diving was because government agencies such as the Arkansas Game and Fish Commission, the U.S. Fish and Wildlife Service, and the U.S. Army Corps of Engineers all needed baseline information on the size and composition of mussel beds in the rivers of Arkansas in order to make management decisions concerning endangered and non-endangered species. Since the late 1800s, mussels have been harvested either for the button industry or 21 the cultured pearl industry. For the button industry, freshwater mussel shells have the ideal hard composition for the manufacture of buttons by hole punch through the shell. For the cultured pearl industry, mussel shell particles are the ideal substrate for the production of artificial pearls. Natural pearls are made by oysters when a piece of sand gets between the mantel of the oyster and its shell; to protect itself from the irritation, the oyster secretes mother of pearl over the sand grain, which over time results in a pearl. In the case of artificial pearls, a freshwater-mussel-shell seed is used instead of a grain of sand. To make seeds, the thick shell is cut into cubes, which are then smoothed into sphere-shaped seeds that can be inserted into oysters. This could be a million-dollar industry in Arkansas, if the market demands the shells. The Dive Rig The standard dive gear utilized for river diving in the twenty-first century is relatively simple to use and extremely safe when used correctly. It generally consists of a gas-powered generator that drives an oil-less air compressor , which stores air in cylinders or a large-volume tank. All of this equipment must be stationed on a dive platform that is usually just an aluminum johnboat or perhaps a small party barge. Sometimes large-volume air cylinders are brought to the dive site already filled with compressed air, but then these must be refilled at a compression station once the air has been drained. If the boat or barge is equipped with a large-volume tank, the compressed air is delivered to the diver through an air hose, usually fifty to one hundred feet in length. The diver then breathes through a specially adapted “hookah” regulator stuffed in the mouth while the eyes and nose are protected by a dive mask, or air may be drawn by normal breathing into a full face mask or dive helmet adapted for relatively low air pressure. The dive rig or surface-based air compressor that we use is itself called a “hookah” after the Turkish tobacco-smoking contraption of the same name. The Turkish hookah is basically a fancy tobacco pipe with several long hoses extending from a centralized compartment that allows several people to smoke from the same pipe simultaneously. In the divers’ version of the hookah, the main body is an oil-less air compressor powered by a small engine similar to a lawnmower engine; the compressor is connected to the diver by two hoses that supply the diver(s...

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