The past 100 years have witnessed some extraordinary exploits in the field of deep-diving research, writes Bernard Eaton.

Deep diving and saturation diving are routine activities in the commercial diving world today. But, as the new century is about to begin, it is interesting to recall how all this came about during the old one.
It is an extraordinary story about extraordinary men who lived in exciting pioneering times and achieved great things.
It is generally supposed that the theory of saturation diving was of relatively recent origin. In fact, it was in 1907 that the renowned John Scott Haldane first established that after a certain time the tissues of animals and human beings became completely saturated with gas.
And as far as mixed gas diving is concerned, American diver Max Gene Nohl descended to 420ft - a record - breathing an oxy-helium mixture as far back as 1937. This was exceeded by 20ft in 1941 by two US Navy divers, Metzger and Conger, breathing oxy-hydrogen. Then in 1948 RN Petty Officer Wilfred Bollard dived on oxy-helium to 540ft, and in 1956 RN Petty Officer George Wookey got down to 600ft using oxy-helium.
This was the prelude to what was to become known as "The Golden Age of Diving", when truly dramatic steps forward were taken. It involved the introduction of saturation diving, intensive activity in diving medical and physiological research, and advances in diving equipment.
In 1957, Capain George F Bond, a shaggy-eyebrowed doctor who was head of the US Naval Medical Research Laboratory, later to be dubbed "The Father of Saturation Diving", began a series of experiments to discover what, if any, were the results of exposures in various animals to normal air and synthetic atmospheres at a pressure of 200fsw.
Under Bond's direction, this led that year to tank experiments with Capt Walter F Mazzone and Capt Robert D Workman which confirmed the theory of saturation diving. Then, in 1962, two US Medical Officers, John Bull and Albert Fisher, spent six days in a helium-oxygen atmosphere at one atmosphere absolute at the US Medical Research Institute, Bethesda, MD, thus finally proving Haldane's theory.
And in April 1963, three volunteers spent six days at 100ft at the Naval Experimental Diving Unit, Washington, in an atmosphere of 7 per cent nitrogen and 7 per cent oxygen, the balance being helium.

Volunteers
The final experiments in Bond's series took place in August and September, 1964, when three volunteers spent 12 days in a chamber at a pressure equal to 198ft.
In the meantime, American millionaire Edwin A Link and Jacques-Yves Cousteau had become involved in underwater living experiments, and Bond had given both the results of his initial experiments in saturation diving.
Link was a brilliant and imaginative inventor who had made his first fortune out of his invention of the Link Pilot Trainer. This was the world's first flight simulator, a device consisting of a cockpit, two pedals, a joy-stick and a compass that enabled pilots to be trained to fly without ever leaving the ground.
Originally developed to teach recreational and commercial pilots, it was eagerly sought by the allied nations when World War II broke out. Winston Churchill was to say that it made an extremely important contribution to the Battle of Britain when pilots were desperately needed.
It was no surprise then that Link launched a "Man in the Sea" project and built a recompression chamber for submergence when he embraced Bond's vision. This was of divers living for extended periods in an underwater habitat with the air inside being in equilibrium with the water pressure outside, leaving the habitat to work, then returning to dry, warm conditions in the chamber.
Cousteau, as everybody knows, had produced the aqualung in 1943 with French engineer Emile Gagnan, who had developed a regulator for gas burners. Cousteau had also mesmerised many thousands of people throughout the world with his book and film The Silent World, which was to lead to an explosion in sport diving activity.
Aware of Bond's results, Cousteau and Link had met and discussed the possibility of collaborating in an underwater living experiment, Link to provide a suitable submerged decompression chamber, Cousteau an underwater house to lock on to it.
It transpired that the aims of the two men differed considerably. Link was seriously dedicated to the principle of saturation diving, believing that any underwater living experiment could only make sense if it addressed the enormous physiological problems of living under pressure. This meant that it had to be conducted at a depth where the difficulties of nitrogen narcosis and decompression were faced.

Experiments
Cousteau was more interested in high-profile underwater experiments which, though conducted at shallower depths, would attract more attention. This eventually proved to be the case due to Cousteau's talent for capturing the imagination of the public and in making headlines. The two therefore decided to act independently.
Link was actually to lead the way - organising the first Ôat sea' saturation dive - and he continued to do so. He designed a small cylindrical chamber and in 1962, although aged 58, he dived down to test and occupy the world's first undersea station at 60ft for 14 hours, including 6 hours of decompression.
A month later, Link made experienced Belgian diver Robert Stenuit the world's first open-sea saturation diver, putting him down to 200ft for 24 hours breathing oxy-helium. Stenuit decompressed for 66 hours, 58 of them on board ship.
Almost simultaneously, Cousteau launched Conshelf One, establishing his own cylindrical ÔHouse Under the Sea', called Diogenes, off Marseilles at a depth of 33ft. Two divers, Albert Falco and Claude Wesly, spent a week submerged. At that depth the problems of narcosis and desaturation were not serious.
In the meantime other things had been happening, this time specifically on the deep diving front. Swiss mathematician Hannes Keller had appeared on the scene in 1961, setting a new Ôfree diving' record of 728ft in Lake Maggiore, breathing a secret gas mixture, with Kenneth MacLeish, a National Geographic magazine Assistant Editor.
Keller and Albert Buhlmann, a Swiss professor of physiology, had developed the mixture which was eventually revealed as being oxygen, helium and nitrogen. This, they claimed, would make it possible for divers to operate at greater depths then ever foreseen.
In December 1962, with the world's media, the US Navy and other interested parties in attendance, a sea dive to 1000ft was set up off Catalina Island, California. Hannes Keller and British journalist Peter Small were to reach that depth in a chamber, swim out to plant two flags on the seabed, then return to the surface in the chamber.
Things went tragically wrong. Peter Small did not survive the dive and a support diver, Chris Whittaker, also died. Keller, however, did survive - thus proving the validity of the gas mixture used and the possibilities that this opened up for underwater operations at depth in the future.
Cousteau continued his experiments in 1963 with Conshelf Two, establishing the first human colony on the seabed in the Red Sea. He imaginatively called the main habitat Starfish House, because as a structure it had four arms. This was anchored at 36ft and five divers were to live in it for a month.
A second habitat, called Deep Cabin, was in 90ft of water close by, and this was used by two divers at a time for as long as a week. Some made excursions from it to depths as great as 165ft. A mobile submersible, which Cousteau called a diving saucer, was garaged in a domed underwater garage.
Link was independently pursuing his aim of extending the depth at which human beings could live under water. His Man in the Sea II project was based on US Navy exposures to 400 fsw for 24 hours, conducted late in 1963.
Link built a collapsible habitat, an 8x4ft inflatable bag on a steel frame anchored to a ballast tray. Called The SPID, for Submersible Portable Inflatable Dwelling, it was lowered to the seabed in the Bahamas in June 1964. Robert Stenuit and marine biologist Jon Lindberg lived in this 'tent' for two days, on oxy-helium, at a depth of no less than 432ft.
Enter the US Navy with Sealab I, in July 1964, near Bermuda. In contrast to earlier experiments, this was designed as a comprehensive and detailed investigation of human physiology underwater. Four divers lived at a depth of 193ft, breathing oxy-helium, but terminated after 11 days instead of 21 because of the sea state.
Sealab II, off La Jolla, California, the following year was the most ambitious underwater living experiment of all times, with three teams of divers spending anything from 10 to 16 days each at 205ft, testing new methods of salvage, new tools, an electrically heated drysuit, porpoise training and making behavioural studies.

Two-storey sphere
At almost the same time, Cousteau was busy with Conshelf III off the South of France. The habitat was a large two-storey sphere, the upper floor for dining, communications and data gathering, the lower for sleeping, sanitation and diving areas. Placed at Cap Ferrat in 328ft of water, a six-man team spent 6 days on the bottom, bad weather preventing a planned 14-day stay.
Sealab III in 1966 would have been the ultimate, the greatest underwater project ever conceived. The plan involved 50 men, trained to dive and conduct scientific experiments at a depth of 620ft, making excursions to 1000ft or more. Unfortunately, the habitat began to flood because of a fault in an electrical hull penetrator, and a diver died in an attempt to solve the problem. As a result, Sealab III was aborted and further experiments of the kind were never again attempted by the US Navy.
In Britain, both amusing and serious things had been happening. For instance, Bournemouth BSAC decided in 1965 to uphold British honour by staging its own saturation diving experiment in Plymouth Sound. Two amateur divers, Colin Irwin and John Heath, bravely spent a week in a small cylinder called Glaucus at a depth of 38ft.
Meanwhile, the Royal Naval Physiological Laboratory, under the direction of Dr Val Hempleman, had been quietly conducting its own experiments, and in 1970 two volunteer members of the Royal Naval Scientific Service broke the world's deep diving record by staying 10 hours at the remarkable simulated depth of 1500ft. One was no less than 26-year-old John Bevan (Underwater Contractor International's Editor!), and the other was 21-year-old Peter Sharphouse.
Shortly after that, the French diving company COMEX made further progress, putting 22-year-old Patrick Chemin and 25-year-old Bernard Reuillier down, in stages, to a simulated depth of 1706ft. The experiment, including decompression, took a total of 14 days, and the two divers spent 5 of them at a depth greater than 1000ft, and 38 hours below 1500ft.

Saturation projects
Between 1972 and 1974, 28 saturation dives to depths of more than 800ft were conducted by RNPL for physiological research, and further deep diving, underwater habitat and saturation projects continued, particularly in the United States.
The result of these, and other, pioneering advances by British, French and US interests, gave birth to an exploitation of the sea's resources that few could have foretold.
The great explosion in saturation diving came when giant commercial organisations, realising the possibilities of oil and gas prospecting, took an interest and moved into areas such as the North Sea, putting into practice all that had been learned about Man's capabilities underwater.
Things have, of course, moved on since then.

© 2000 Underwater World Publications Ltd.