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The ocean. Mysterious, vast, beautiful… full of water. Lots of water. And fish, plant life, coral- - isn’t it clear why the deep blue sea has fascinated humans? Can’t you just imagine one of the early human beings, sitting by the shore, thinking to him or herself, “Hmmm, how can I get to the bottom of this?” Nowadays, we see people on television wearing scuba suits and dropping into the deep ocean like lumps of sugar into tea. No big deal, we think. People can explore the ocean with a snorkel set during an island vacation, if they want to. No big deal!

But, it is a big deal. If people hadn’t figured out how to go underwater for great lengths of time, we would not have many of the advantages that we enjoy in modern society. Bridges like the Golden Gate Bridge- - or underwater tunnels, like the tunnel that connects England to the European continent- - would not exist. We would not know the identity of vast numbers of species of fish and sea life. Heck, think about how many sunken treasures would remain lost at sea if people hadn’t figured out how to sustain themselves underwater for long periods of time.

The average person can hold their breath for less than two minutes. Experienced skin divers, for example, can hold their breath for several minutes while they seek oysters that contain pearls, and other treasures. As far as the ancient Greeks were concerned, several minutes did not allow a diver enough time to be underwater. The famed Greek philosopher, Aristotle, made reference to an underwater diving apparatus used by Alexander the Great in 332 BCE. Apparently, Alexander needed to clear the harbor surrounding the ancient city of Tyre of debris. So, a bell-shaped apparatus was created from wood. The idea was that the bell would be placed over the diver’s upper body while he or she walked on the sea’s floor. The air trapped under the bell would gain enough pressure that it would dispel any water. Thus, the diver would be able to breathe and see underwater.

This diving bell was not greatly improved upon until 1616, when a German inventor named Franz Kessler created a diving bell that extended all the way down to a diver’s ankles. The diver thus had more air to breathe, and less water between him or her and the ocean floor. Then, in 1716, astronomer Edmond Halley of England invented a diving bell that contained windows and was connected to the surface with leather tubes. The tubes connected to air casks would be lowered into the water, as the diver needed them. When the casks were lowered below the diving bell, the air pressure increased, and the air was forced into the bell so that the diver could breathe. This allowed a diver to remain underwater for up to an hour and a half at depths of 60 feet (18 m) underwater. Wow!

Now, diving bells are still used, though they are constructed of steel, which can withstand much higher water pressure. Work can be done underwater on bridges, jetties and piers thanks to the diving bell. Lighting, heat and communication systems have been put into these bells so that workers are able to enjoy a more comfortable climate as well.

Since diving bells did not allow the freedom of movement that divers craved, another system of underwater exploration was invented. In 1819, a German inventor named August Siebe created a diving suit that allowed a person to wear a helmet into which air would be pumped. The helmet was constructed out of copper, and was connected to a canvas suit. Hoses were attached to the helmet, right under the diver’s chin, so that the air pressure would flow upwards. Weights were added to the diver’s suit, so that the air pressure would not cause the diver to rise. This suit allowed a diver a lot more freedom to move, however it also granted the diver more ability to see. The diving bell provided a view of the ocean floor, but the new suit gave the diver the ability to have a view of all directions.

Variations on the initial suit followed: valves were installed to control buoyancy, rubber was used for the suit itself in order to keep the diver dry. It was just a matter of time until a self-contained underwater breathing apparatus (SCUBA) was invented. In 1865, two French inventors named Benoit Rouquayrol and Auguste Denayrouze, created a suit that was connected with hoses to the surface, but also contained additional storage of air to be carried in tanks on the diver’s back. Since the compressed gas cylinders of that period were inefficient, the suit was not very practical. The idea was in place, however, and as soon as cylinders advanced, so to did the scuba suit advance.

In 1943, two Frenchmen named Jacques Cousteau and Emil Gagnon introduced a new invention called the Aqua-Lung. It was composed of a valve-operated hose that carried air to the diver’s mouth from a high-pressure cylinder. The diver wore this Aqua-Lung on his or her back while paddling around the deep ocean. For the first time, humans could move freely about the recesses of the deep blue sea- - as long as their tanks were filled with air. Anyone in decent physical condition could learn to use the scuba gear to explore the depths for their own enjoyment, as well as for work. You too can learn how to scuba dive. What are you waiting for? Anchors away!