Into the blue

Diving bells are shaped like upturned glasses and have been around in one form or another since ancient times. The diver breathes the air trapped inside the bell but there is no circulation, meaning that the diver risks suffocating without frequent return trips to the surface. While far from perfect, the diving bell represented the starting point for man's equipment-based underwater adventures.

In 1826, Jean-Jérémie Poulliot filed a patent for a pneumatic regulator to be used for breathing underwater. As its name suggests, the regulator provided the diver with regular supplies of air at ambient pressure. Although the invention did not achieve lasting success, it represented a key step forward for 20th-century professional diving.

In 1833, François Magny patented a system that fed air from the surface down to the diver. Although the idea was nothing new, his device had a novel metal wire frame with a waterproof cover inflated with air to resist the pressure of the water. There is no evidence that it was ever used, yet Magny's device paved the way for the development of the atmospheric diving suit.

In the first quarter of the 19th century, the quest for underwater autonomy lead Jean Jérémie Poulliot to design his very own regulator. However, the technical inability to inflate a container subject to water pressure so that it would provide enough air made it impossible to create autonomous equipment. As a result, diving devices fed by one or two tubes continued to be used. However, a device patented by Manuel Théodore Guillaumet marked a turning point. It had a regulator tank worn on the diver's back, a vest that could be inflated with air at will, and an air-supply system consisting of a pump and intermediate tank. The latter stored the pressurized air before it was supplied through a tube to the diver, while the pressure regulator provided ambient-pressure air through a mouthpiece. With this design, Guillaumet's device offered a glimpse into the future of diving equipment.

In the middle of the 19th century, a new type of "open" diving equipment was invented with an air-intake hose attached to the helmet at neck level. The air then exited the corset at belt level. Vincent Gibert's diving device marked a real turning point in the evolution of individual dive equipment and was the first equipment of this kind to be patented.

On November 27, 1847, Napoleon-Antoine Wolski patented his diving apparatus: the aquatic armor suit. The diver was shut inside a rigid device with metal armor covering his entire body and the joints had hinges that the inventor called "lobster tails." Wolski became the first inventor to hold a patent for a rigid metal armor device.

Despite its name, the device patented by Jean-Jacques Danduran in 1843 was in fact more like an individual diving bell. The inventor wanted to avoid the dangers of having the diver breathe compressed air. However, the device had a major defect: it could only be used in shallow water. This was because water rose inside the helmet in proportion to the corresponding depth, meaning that at a depth of 10 meters it was half full. Although the diver could still breathe at this point, this would become impossible just a few meters further down.

The Delange and Ernoux advanced rescue device was an open apparatus for which a patent was filed in 1853. Air was supplied through a hose attached to a pump which delivered a continuous flow of air to stop water entering via the bottom of the suit. Two men worked the pump while a third handled the tube and safety rope attached to the diver's belt. Given the boom in demand for work carried out underwater, Delange and Ernoux set up their own underwater works company.