History of scuba diving
The history of scuba diving goes back centuries. People have been diving underwater throughout the ages, probably for as long as people have been swimming. It may not have been scuba diving per se (defined as diving with compressed air or other gas mixture that is carried by the diver) but it is the beginnings of the quest to be able to dive and to breath underwater. In very early times the methods used, such as hollow reeds and inflated bags of air were largely limiting, both in terms of depth as well as the time this allowed the swimmer to stay underwater. His is an account of the main milestones since the beginning of the 18 th century
18 th century
Early attempts to reach autonomy from the surface were made by the Englishman John Lethbridge, who invented and successfully built his own underwater diving machine in 1715.
The first diving dress using a compressed air reservoir was successfully designed and built in 1771 by Sieur Fréminet, a Frenchman from Paris. After having done research on surface-supplied diving he conceived an autonomous breathing machine equipped with a reservoir, dragged by and behind the diver. Fréminet called his invention machine hydrostatergatique and used it successfully for more than ten years in the harbors of Le Havre and Brest.
19 th century
The Frenchman Paul Lemaire d'Augerville successfully built and used autonomous diving equipment in 1824, as did the British William H. James in 1825. James' helmet was "thin copper or sole of leather" with a plate window, and the air was supplied from an iron reservoir.
A similar system was used in 1831 by the American Charles Condert, who died in 1832 while testing his invention in the East River at only 20 feet / 6 m deep.
The oldest known oxygen rebreather was patented on June 17, 1808 by Sieur Touboulic from Brest, mechanic in Napoleon's Imperial Navy, but there is no evidence of any prototype having been manufactured. This early rebreather design worked with an oxygen reservoir, the oxygen being delivered progressively by the diver himself and circulating in a closed circuit through a sponge soaked in limewater. The oldest practical rebreather relates to the 1849 patent from the Frenchman Pierre Aimable De Saint Simon Sicard.
The Rouquayrol-Denayrouze apparatus, invented by Benoît Rouquayrol in 1860 for survival in flooded mines and adapted to diving in 1864 with the help of French Navy officer Auguste Denayrouze, was the first regulator to be mass-produced (from 1865 to 1965). Even though it was independent from the surface for a very short duration, the Rouquayrol-Denayrouze apparatus reached worldwide celebrity after having been mentioned by Jules Verne in his adventure book Twenty Thousand Leagues Under the Sea; but Jules Verne wildly exaggerated its dive duration without external air supply. The iron reservoir suffered from a lack of autonomy because the technology of that time was not yet able to provide reliable valves and pressure vessels when gases were highly compressed. That is why the Rouquayrol-Denayrouze reservoir, in the 1860s, was able to contain only 30 atmospheres of internal pressure, which translated into sufficient air to permit dives no longer than 30 minutes to a depth of no more than ten meters. For a longer and more secure autonomy from the surface technology had to wait until the 20th century had brought stronger and reliable compressed air cylinders.
20 th century
The first diving equipment that combined a high-pressure cylinder and a breathing device was invented separately by the Japanese Ohgushi in 1918 and the Frenchmen Maurice Fernez and Yves le Prieur in 1926. Both were based on a constant-flow supply of the air. Ohgushi's invention was soon forgotten, but the Fernez-Le Prieur apparatus was mass produced during the 1930s and adopted as a standard by the French Navy. It was also the autonomous breathing device first used by the first scuba diving clubs in history, both in the USA and in France.
During the 1930s French pioneers Philippe Tailliez and Jacques-Yves Cousteau used and widely tested the Le Prieur apparatus before Émile Gagnan and Cousteau worked together on the invention of the modern regulator and first commercially successful scuba sets, coined the Aqua-Lung, in 1943.
These first scuba sets were twin hose open-circuit units, in which compressed air carried in back mounted cylinders is inhaled through a demand regulator and then exhaled into the water adjacent to the tank. The single hose two stage scuba regulators of today trace their origins to Australia, where Ted Eldred developed the first example of this type of regulator, known as the Porpoise, in 1952. The single hose regulator separates the cylinder from the demand valve, giving the diver air at the pressure at his mouth, not that at the top of the cylinder.
In the 1940s and 1950s all scuba sets came with a plain harness of straps with buckles like on a rucksack. Scuba divers therefore dived without any buoyancy aid and, in an emergency, they had to jettison their weights. In the 1960s adjustable buoyancy life jackets (ABLJ) for aqualung-type scuba became available. The ABLJ was used for two purposes: one to adjust the buoyancy of the diver to compensate for loss of buoyancy and more importantly as a lifejacket that can be quickly inflated even at depth. The first ABLJ were inflated with a small carbon dioxide cylinder, later with a small air cylinder. It was the invention by French company Scubapro in 1971 of the "direct system" (an extra hose from the first-stage regulator that directly feeds into the lifejacket) that resulted in what is now commonly known as a buoyancy compensator device, or simply “BCD or BC”.
The 1950s and 1960s saw the birth of a number of scuba diving training and certification agencies as a result of climbing accident rates for scuba divers. BSAC was formed in 1953, CMAS in 1959, NAUI in 1960 and PADI in 1966.
Divers Alert Network (DAN) was founded at Duke University in 1980 as a non-profit organization to promote safe diving.
The first commercially available dive computer, the Orca Edge, was introduced in 1983. Until then, all scuba diving was one based on manual dive tables. Today, dive computers are becoming common equipment among recreational divers.
Scuba diving experienced tremendous growth until the turn of the century with the number of new divers progressively stabilizing since then. In 2012, an estimated 1 million new divers were certified. Scuba diving remains a young and dynamic sport as witnessed by the continued evolution of dive equipment and dive practices. In recent years, the use of dive computers has become standard and many certification agencies now incorporate this piece of equipment into their training curriculum. One of the most significant innovations of the past years is the wireless integration of air consumption into the algorithms of dive computers. By incorporating this additional factor into the calculation of remaining bottom-time, diving is becoming even safer.