The First Discoverers

While the deep sea has held a fascination for people since the dawn of civilization, it was only lately and slowly that they have broken the mirror and attempted explorations of the abyss. History tells us of often disorganized efforts, which were always possessive of a mad gallantry, by the first men attempting to become aquatic explorers, yearning to save devoured treasures.

In the early fifth century BC, a certain Scyllias of Scione contributed to the defeat of the Persians during the Median wars by going under water and releasing the anchors of Xerxes's ships.
In the fourth century BC, Aristotle mentions that "...one can allow divers to breathe by lowering a bronze tank into the water. It will not fill up with water, but keeps its air when lowered vertically..." Later on, in Rome, Urinators were professionals who recuperated rich cargoes from sunken ships.

However, until the seventeenth century, progress was slow, in spite of the designs of some ingenious inventors, such as Leonardo da Vinci. On the other hand, the impetus given by Kessler and Halley, among others, initiated a long series of research and inventions which have not yet ceased.

Undersea exploration has systematically progressed from the first diving bell to the autonomous diving suit of Gagnan and Cousteau. Gradually, man has liberated himself from the surface, reaching working depths of 300 meters, forays up to 600 meters, and dives up to 11,000 meters in submarines.