When Europeans discovered the gold, gems and silver accumulated by civilizations in the Americas, convoys of ships laden with the riches grabbed, set out across the Atlantic. Many treasure ships were lost in storms in deep water, but others went down in shallower water. The Europeans may not have been aware that toredo worms could have consumed the better part of their ships’ structural integrity by the time they had loaded it with tons of gold. For some, all it took was a light puff to add enough stress on the hull to open up the seams on the way out of the harbor. The Spanish recruited local native divers for these recovery operations. Among these people, the Caribs in the Carribean and the Lucayans in the Bahamas, women were often the better divers. It was not because they didn’t smoke the huge cigars traditionally rolled there, for they did, but they naturally had more body fat than the men which made the cold water more bearable. Women are known to be the divers in others places like Tierra del Fuego and among the Ama women of Japan. The Ama lived with their families on boats and were thought capable of diving to 100 feet without gear. When Columbus found the Carribean natives had huge quantities of pearls, the Spanish king established a pearl fishery. Free diving for treasure or pearls, men and women dove for the Spanish, who soon enslaved them. They were pressed to dive deeper, stay down longer and to do it day after long day. Between European disease and the work load, the diver population was killed off in a few short years. The Spanish then brought over enslaved Africans to dive. Military projects produced some technological advances, but it was the commercial profit motive that drew the most divers. Although they were limited to shallower dives initially, divers were recruited to recover cargo and equipment from sunken treasure, cargo and military ships. A metal or wood bell shape was used to trap an air supply that free divers could use by reentering the air space under the open bottom. By the 1790s most European harbors had a diving bell to aid in salvage projects. In European ports and later in America, diving was focused on the salvage of commercial and military vessels. The use of a diving bell goes back to 340 B.C. when Alexander the Great went down in a glass one. The first bells held only the air captured as they were lowered into the water. Later an air line was used to provide air to the bell. Around 1690 astronomer Edmund Halley, of Halley’s Comet fame, developed a system for lowering lead casks of air to bell divers. A tube ran from the cask to the bell. This innovation and a recovered large Carribean treasure using the bell resulted in many salvage companies opening in Europe. Early use of Halley’s innovation resulted in opening access to new ocean depths. One of the strangest early diving stories unfolded in 1790, when divers using a Halley diving bell were sent to Seraglio Point in the Bosporus to salvage a wreck. The Bosporus Strait connects the Black Sea and the Sea of Azoz. It also separates east and west Turkey at Constantinople. Today it is the busiest shipping lane on the planet. Only minutes after their decent, the divers signaled frantically to be brought back up. The terrified divers refused to go down again. They had seen on the bottom hundreds of lifesize dolls shaped like bowling pins with skulls for heads. There were rows of them jammed tight, others swayed together in the current, many more were knocked over. All the skulls wore a macabre grin. The divers had come upon the spot where for generations concubines had been ritually murdered. They had been sewn alive into sacks weighted with stones and only their heads exposed, then thrown into the sea at night from boats. They may have been victims of palace intrigue or perhaps they had insulted the sultan. One sultan who reigned in the 1640s was said to have drowned his entire harem of 1200 concubines. Harems at the time had gained considerable political power and became a force to be reckoned with for some sultans. It was in the often lucrative salvage business that diving technology slowly evolved. Salvaging sunken ships was a more continuous endeavor than military schemes. The demand for more effective means of salvage in deeper water drove the development of the equipment. Some of the equipment described in early drawings and texts on diving was fairly cockamamie stuff that was either never tested or tried once unsuccessfully, sometimes fatally, before the physics and biology of diving was much understood. Englishman Charles Deane built the first functional helmet for use in burning buildings in 1827. It was used by divers who wore it strapped over a diving suit. However, stumbling on the bottom could tilt the helmet and fill it with water. Frenchman August Seibe devised a means of making an air tight seal between the helmet and suit. This was the beginning of modern helmet diving. Seibe’s gear was used to salvage the 108-gun British warship Royal George, on the bottom for 50 years in 65 feet of water. Their navy’s largest ship, it had sunk at its anchorage taking 1,000 lives. The project generated many diving firsts in both achievements and injuries, including the first recorded case of “the squeeze.” The squeeze, every helmet diver’s continuous nightmare, occurs when a loss of air pressure in the helmet sucks the flesh off the diver’s bones and squeezes it into the helmet.
Diving into deeper water meant confronting the fact that for every 33 feet in depth the pressure increases one atmosphere (the pressure on the surface or 14.7 pounds per square inch) and the effects that has on gases in the bloodstream. The bends was recognized as a problem for divers as early as the 1700s, but it was not understood at the time. When a diver breathing air rises too quickly, nitrogen from that air is driven into the body’s tissue causing the body to painfully contort, sometimes causing death. Another effect is nitrogen “narcosis” in which the diver, overcome by the gas, drifts into a semi-conscious helpless state, also referred to as “rapture of the deep,” which divers compare to being drunk on alcohol. Progress toward diving deep and having mobility was slowly made, though the science was little understood. As early as the 1500s there were conceptual proposals for scuba gear (self-contained underwater breathing apparatus) by Leonardo di Vinci and others. Di Vinci, at the time, known more as a designer of military equipment than an artist, drew scuba gear that in principal was much like modern gear, but in practice would not have worked. His system had divers rebreathing carbon dioxide. Not until 1865, when French mining engineer Benoit Rouquayrol developed a membrane regulator that sent air to the diver’s mouthpiece only when he took a breath, was practical scuba gear possible. It was the single most important device in the development of modern scuba gear. In Rouquayrol’s design, air was pumped from the surface to a metal cylinder on the back of a diver wearing a helmet and suit. Though not fully self-contained, since it relied on air from the surface, it could detach for short periods. The most important innovation was the regulation of air to the diver’s mouth. The regulator’s membrane was sensitive to the water pressure outside and sent air to the diver only when he breathed. Previously air went to the diver constantly. Scuba was sidestepped however, for development of helmet diving. Deeper dives brought new problems, some of which were not resolved until the ratio of nitrogen to oxygen was changed in 1912 by a German company. Air, which is 71% nitrogen and 29% oxygen, was remixed with more oxygen. That year decompression tables were devised by Scottish physiologist John Haldane after the first detailed studies of the cause and symptoms of decompression sickness were published. The first experimental dives with helium-oxygen mixtures were in 1924. It was development in the 1930s and 1940s that made scuba diving possible and popular in the next two decades. Rubber goggles were designed by Guy Gilpatric in 1930 and were soon commonly used with snorkels. In 1933 a demand valve, high pressure tank and patented swim fins were produced. But Rouquayrol’s regulator was the missing link in the development of modern scuba gear. It had been neglected for years until 1942 when Jacques Cousteau, a pioneering French navy diver in the Mediterranean, and Emile Gagnan combined a Rouquayrol-type regulator with an existing compressed air cylinder to reach greater depths. The pair made a few minor changes to an existing air hose and mouthpiece to create the Aqua-Lung in 1943. In that year French diver Frederic Dumas made a record dive with it to 220 feet and four years later went to 307 feet. The first Aqua-Lung regulators were imported into the U.S. in 1948. Divers quickly adopted the use of them and the popularity of diving spread. In 1956 the first wet suit was made at the University of California. Compressed air is considered unsafe below 200 feet because of nitrogen narcosis, but with helium-oxygen mixtures and diving tables an Aqua-Lung diver can go as deep as a helmet diver. In 2001 John Bennett broke his own record diving to 308 meters (1,010 feet). Compared to the equipment and knowledge of early helmet diving, modern recreational scuba diving is more like a walk in the woods. Commercial scuba diving however, can place divers in conditions that compound the hazards of being in a place humans were not meant to go.
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