1535 - Guglielmo de Loreno developed what is considered to be a true diving bell.

1650 - Von Guericke developed the first effective air pump.

1667 - Robert Boyle observed a gas bubble in the eye of viper that had been compressed and then decompressed. This was the first recorded observation of decompression sickness or "the bends."

1691 - Edmund Halley patented a diving bell which was connected by a pipe to weighted barrels of air that could be replenished from the surface.

1715 - John Lethbridge built a "diving engine", an underwater oak cylinder that was surface-supplied with compressed air. Water was kept out of the suit by means of greased leather cuffs, which sealed around the operator's arms.

Figure 1. Halley's diving bell, late 17th century. Weighted barrels of air replenished the bell's atmosphere. (U.S. Navy Diving Manual)

1776 - First authenticated attack by military submarine - American Turtle vs. HMS Eagle, New York harbor.

1788 - John Smeaton refined the diving bell.

1823 - Charles Anthony Deane patented a "smoke helmet" for fire fighters. This helmet was used for diving, too. The helmet fitted over the head and was held on with weights. Air was supplied from the surface.

1828 - Charles Deane and his brother John marketed the helmet with a "diving suit." The suit was not attached to the helmet, but secured with straps.

1837 - Augustus Siebe sealed the Deane brothers' diving helmet to a watertight, air-containing rubber suit.

Figure 2. Siebe's early diving suit. (U.S. Navy Diving Manual)

1839 - Seibe's diving suit was used during the salvage of the British warship HMS Royal George. The improved suit was adopted as the standard diving dress by the Royal Engineers.

1843 - The first diving school was established by the Royal Navy.

1865 - Benoit Rouquayrol and Auguste Denayrouse patented an apparatus for underwater breathing. It consisted of a horizontal steel tank of compressed air on a diver's back, connected to a valve arranged to a mouth-piece. With this apparatus the diver was tethered to the surface by a hose that pumped fresh air into the low pressure tank, but he was able to disconnect the tether and dive with just the tank on his back for a few minutes.

1876 - Henry A. Fleuss developed the first workable, self-contained diving rig that used compressed oxygen .

Figure 3. Aerophore patented in 1865 by BenoitŒt Rouquayrol and Auguste Denayrouse. (Courtesy Historical Diving Society)

1878 - Paul Bert published La Pression Barometrique, a book length work containing his physiologic studies of pressure changes.

1908 - John Scott Haldane, Arthur E. Boycott and Guybon C. Damant, published "The Prevention of Compressed-Air Illness", a paper on decompression sickness.

1912 - The U.S. Navy tested tables published by Haldane, Boycott and Damant.

1917 - The U.S. Bureau of Construction & Repair introduced the Mark V Diving Helmet. It was used for most salvage work during World War II. The Mark V Diving Helmet became the standard U.S. Navy Diving equipment.

1924 - First helium-oxygen experimental dives were conducted by U.S. Navy and Bureau of Mines.

1930 - William Beebe descended 1,426 feet in a bathysphere attached to a barge by a steel cable to the mother ship.

1930s - Guy Gilpatric pioneered the use of rubber goggles with glass lenses for skin diving. By the mid-1930s, face masks, fins, and snorkels were in common use. Fins were patented by Louis de Corlieu in 1933 .

1933 - Yves Le Prieur modified the Rouquayrol-Denayrouse invention by combining a demand valve with a high pressure air tank to give the diver complete freedom from hoses and lines.

1934 - William Beebe and Otis Barton descended 3,028 feet in a bathysphere.

Figure 4. Vertical cross section of the McCann-Erickson Rescue Chamber. (Courtesy U.S. Navy Diving Manual.)

1940 (breath-hold; scuba). First year of production of Owen Churchill's swim fins. Initially, only 946 pairs are sold, but in later years production increases substantially, and tens of thousands are sold to the Allied forces.

1941-1944 - During World War II, Italian divers used closed circuit scuba equipment to place explosives under British naval and merchant marine ships.

1942-43 - Jacques-Yves Cousteau and Emile Gagnan redesigned a car regulator that would automatically provide compressed air to a diver on his slightest intake of breath. The Aqua Lung was born.

1946 - Cousteau's Aqua Lung was marketed commercially in France. (Great Britain 1950, Canada 1951, USA 1952).

1947 - Dumas made a record dive with the Aqua Lung to 307 feet in the Mediterranean Sea.

1948 - Otis Barton descended in a modified bathysphere to a depth of 4500 feet, off the coast of California.

1951 - The first issue of Skin Diver Magazine appeared in December.

1953 - The Silent World by Cousteau was published chronicling the development of the Cousteau-Gagnan Aqua Lung.

1950s - August Picard with son Jacques pioneered a new type of vessel called the bathyscaphe. It was completely self-contained and designed to go deeper than any bathysphere.

1954 - Georges S. Houot and Pierre-Henri Willm used a bathyscaphe to exceed Barton's 1948 diving record, reaching a depth of 13,287 feet.

1957 - The first segment of Sea Hunt aired on television, starring Lloyd Bridges as Mike Hunt, underwater adventurer.

1959 - YMCA began the first nationally organized course for scuba certification.

1960 - Jacques Picard and Don Walsh descended to 35,820 feet in the bathyscaphe Trieste.

1960 - NAUI was formed.

1962 - Beginning in 1962 several experiments were conducted whereby people lived in underwater habitats.

1966 - PADI was formed.

1968 - John J. Gruener and R. Neal Watson dove to 437 feet breathing compressed air.

1970s - Important advances relating to scuba safety that began in the 1960s became widely implemented in the 1970s, such as certification cards to indicate a minimum level of training, change from J-valve reserve systems to non-reserve K valves, and adoption of the BC and single hose regulators as essential pieces of diving equipment.

1980 - Divers Alert Network was founded at Duke University as a non-profit organization to promote safe diving.

1981 - Record 2250 foot-dive was made in a Duke Medical Center chamber.

1983 - The Orca Edge, the first commercially available dive computer, was introduced.

1985 - The wreck of the Titanic was found.

1990s - An estimated 500,000 new scuba divers are certified yearly in the U.S., new scuba magazines form and scuba travel is big business. There is an increase of diving by non-professionals who use advanced technology, including mixed gases, full face masks, underwater voice communication, propulsion systems, and so on.

The above information was obtained from Scuba Diving Explained by Lawrence Martin, M.D.