In underwater or maritime archaeology we learn about the past from maritime finds, usually shipwrecks, but also dwellings and ports. The cold waters in the Baltic Sea in Northern Europe have a unique collection of well preserved wrecks from times past, and most of them have not been located ­ yet. Along the coastlines, not only in Northern Europe but worldwide, many thousands of ships have perished. They are laying there as a link to the past.

Many of Earth's best kepy secrets lie buried beneath the Ocean floors - lost as the planet went through cycles of change. man has always been an explorer - the oceans, seas and rivers, linked to folklore about ancient myths and lost civilizations and cities.

Our souls have always been drawn to the Sea. Most people desire to live in a home that faces out to the sea. It represents the unconscious mind - the collective unconsious - creation - always drawing us back to discover its secrets.

Interest in underwater archaeology, a previously limited discipline is growing with the development of new technology. In modern archaeological history, it was the last field of the discipline to gain respect in academia. However, the history of underwater archaeology goes back far into the Earth's past.


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.

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.

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 .

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.

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 beginnings of the diving bell are undoubtedly in the use of primitive but functional devices, containers such as buckets or cauldrons. These devices trapped air when inverted and were placed over the diver's head before he entered the water.

Aristotle was an early observer of such practices. In the 4th century BC he wrote, "...they enable the divers to respire equally well by letting down a cauldron, for this does not fill with water, but retains the air, for it is forced straight down into the water."

Many centuries later, in 1771, an unknown author, in an article on the diving bell in the first edition of the Encyclopaedia Britannica, offered an explanation of trapped air as it worked in a diving bell, with complications beyond those encountered in the use of a simple inverted container. "The air in a diving bell is compressed by the weight of the atmosphere before the bell is let down into the water.

But when it has sunk 35 feet below the surface, the air contained in it is compressed by the weight of the atmosphere as before, and by the weight of 35 feet of water besides, which is equivalent to another atmosphere.

Therefore the compressing force at this depth is doubled, and consequently the air in the bell will then be twice as dense as the compressed air that we breathe.

As much air, likewise, as just fills the bell, when it is a the surface of the water, will, at the depth of 35 feet, fill only half of it, for as the compressing force is doubled, the same quantity of air will be reduced to half its usual dimensions.

For this reason, the water would rise into the bell through the base or bottom of it, which is always open, and would fill the other half of it if there was not a contrivance for bringing down additional air enough to force out this water, and to keep the whole capacity of the bell full of air." (Vol. 3, 1771) He goes on to describe a device for bringing down fresh air and also to comment upon the problem of the air being heated.

Other observers have remarked that the heating of the air, by breathing and by pressure, posed a problem for bell divers. Aristotle, in his work Problemata, tells the tale of Alexander the Great.

At the siege of Tyre, in 332 BC, he was lowered in a diving bell, also noted in the Roman 12th century Alexandriad which, in iambic lines of six feet or twelve syllables of verse (hence the term Alexandrine) relates the tale that Alexander had built "a very fine barrel made entirely of white glass" which was towed out to sea and lowered into the water.

In the Alexandriad version, two companions accompanied Alexander and all were stunned by what they saw by the bright lights emanating from the diving machine. Alexander is quoted as observing, from what he had seen underwater, that "...the world is damned and lost.

The large and powerful fish devour the small fry." Yet another story regarding Alexander's underwater adventures was published in 1886 in France. This book on Alexander reported that, at the age of 11, Alexander entered a glass case, reinforced by metal bands and had himself lowered into the sea by a chain over 600 feet long.

Such accounts, while fanciful, demonstrate the long-standing interest in undersea exploration. Searle points out a fact that makes the event even more fanciful, that in the era stated as the date of the plunge, the metallurgy of the time was so primitive that any chain links forged would have been too weak to sustain such a weight.

Some centuries later, circa 1250, the Franciscan monk, Roger Bacon, in his work, De Mirabili, speaks of devices which can be "made by means of which men could walk on the bed of the ocean without harm to their bodies. Alexander used such a device in order to discover the secrets of the sea." Lord Bacon, Francis Bacon, in his classic philosophical work, Novum Organum (1620) describes an "...apparatus which has sometimes been used to work on submerged vessels, and which enables the diver, by returning to it from time to time to breathe, to remain for a very long time under water."

He goes on to detail its construction: a hollow metal vessel lowered into the sea, carrying a supply of air in a manner similar to the diving bell and what, in modern diving would be called a "telephone booth" where divers could pop in for a breath of fresh air.

Francis Bacon's hollow metal vessel lowered into the sea was similar in concept to the type of diving bell invented by Lorini, reported in his book on fortifications in 1597. This device was a square wooden contraption, bound with iron bands, the diver sitting on a stone for ballast, with glass ports. Lorini viewed the advantages of this device as providing the means for recovering pieces of artillery from the sea, fastening cables and the like. "And, " he observed, "apart from this they are very useful for gathering coral."

Perhaps the earliest accurate report of a diving bell successfully used is that of Lorena's device, described in a work published in 1599 by de Marchi. Lorena's bell covered the top half of the diver's body, had a glass port for observation, and the operator could extend his hands from under the rim. It was used in an attempt to recover Caligula's pleasure galleys in Italy's Lake Nemi.

A few years later, in 1538, a German writer whose name is variously spelled "Tassinier," Taisnier" and "Tasinier" and who worked for the Emperor Charles V, accompanied the Emperor to Toledo where they witnessed, along with ten thousand other spectators, two Greek divers in a demonstration of a diving bell.

"They suspended a large Kettle to ropes, having its mouth inverted, and planks fixed within it to sit upon; and in this situation, taking with them a lighted candle, they decended [sic] to the bottom.

The Kettle was equipoised by means of lead fixed round its mouth, and by the weight of which it sunk. When it was drawn up, to the great astonishment of all present, the men were not wet, nor was the candle extinguished!" Davis suggests the Greeks were jongleurs, trick performers used to engaging in acts of skill and daring, and, furthermore, the depth reached in the River Tagus could not have been significant.