What's a diving bell?

By: Charles W. Bryant

Marine Life Image Gallery Early images of diving bells depicted hard-to-believe scenarios. See more pictures of marine life.
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Since man has walked the Earth, it seems like we've been fascinated with two things we weren't built to do -- fly like birds and swim like fish. We've all seen grainy black and white footage of some of the early flying machines, most of which involved mimicking the flight of birds by attaching wings to a human in some fashion. What doesn't exist so readily are images of our early attempts to become fishlike. This is mostly due to the lack of availability of underwater filming techniques at the time. But we do have some record of our quest for going underwater and staying there for prolonged periods.

The Greek philosopher Aristotle wrote about man's desire to spend time under the sea way back in the 4th century B.C.:



What Aristotle was referring to was the earliest version of the diving bell. This was the first attempt man made at submersing himself underwater for an extended length of time, and laid the foundation for what would centuries later become scuba diving.  Since Aristotle was a teacher of Alexander the Great, it should come as no surprise that the young conqueror allegedly used a diving bell several times -- at the age of 11 and then later at the Siege of Tyre in 332 B.C. These stories are not likely to be true, but there are paintings of Alexander sitting inside a glass barrel at the bottom of the ocean, so we know that the idea was in place. Inventor and artist Leonardo da Vinci also sketched early versions of the diving bell, though it's believed that like many of his inventions, he never followed through on its construction.

Read on to find out exactly what a diving bell is, how it works and when it was actually invented.


Diving Bell Beginnings

Many designs of diving bells aren't bell-shaped at all.
Many designs of diving bells aren't bell-shaped at all.
x Photos/Getty Images








Diving Bell Innovations

Diving bells were sometimes attached to frigates and schooners.
Diving bells were sometimes attached to frigates and schooners.

The first real innovation to the diving bell came when Frenchman Denis Papin figured out how to get fresh air into them in 1689. Flexible hoses attached to bellows ran into the water and up inside the bell, providing fresh, breathable air. While this helped divers stay submerged longer, it did nothing to combat the pressure and to allow for deeper dives. The next obstacle was to figure out how to get pressurized air into the bell, something Englishman Edmund Halley did just a year later.

Halley attached weighted wooden barrels to the diving bell. At the bottom of each was a hole in the side that allowed water to come in, forcing the air up. At the top, a hose ran from the barrel and led to the bottom side of the bell, where it was attached with a faucet head. The divers inside could simply turn the faucet to allow the fresh air to flow in. The barrels were alternately pulled to the surface for "refilling," and dropped back in again. By being able to control the amount of air in the bell, the divers were able to match the pressure of the displaced water. Halley's innovation made the pressure of the interior of the bell equal to that of the surrounding water.


Things went on like this for a while, until English scientist John Smeaton invented the diving air pump in 1788. The surface pump was attached to the roof of the bell and operated by four men. In the end, it was, in concept, much like Denis Papin's original plan 100 years earlier. Using this new technology, workers were able to descend in a diving bell and repair the foundation of the Hexham Bridge in England. Smeaton also was one of the first to make the bells square, calling them "diving chests."

Other improvements over the years included adding electric lighting inside, thick convex lenses as windows, and increasing the interior space so that as many as 12 men could descend at a time. The earliest applications of the bells were to transport workers under water so that they could repair or build docks, lighthouse foundations and bridges. Early enthusiasts also tried their hand at deep shipwreck salvage, something the bells are still used for today.


Lots More Information

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More Great Links

  • "Diving Bell Chronology." Thinkquest.org. 2009.http://library.thinkquest.org/28170/221.html
  • "Diving Bell." Kenyon.edu. 2009.http://physics.kenyon.edu/EarlyApparatus/Pneumatics/Diving_Bell/Diving_Bell.html
  • "Diving bells and Observation chambers." Divingheritage.com. 2009.http://www.divingheritage.com/chambers.htm
  • "Modern Diving Bells and chambers." Divingheritage.com. 2009.http://www.divingheritage.com/bells.htm
  • "The Incredible Aqualung of the Diving Bell Spider." Environmentalgraffiti.com. July 28, 2009.http://www.environmentalgraffiti.com/featured/incredible-aqualung-diving-bell-spider/13855
  • Bachrach, Arthur J. "The History of the Diving Bell." Thehds.com. 1998.http://www.thehds.com/publications/bell.html
  • Pike, Paul Scott. "Bermuda Bell Diving." Experiencebermuda.com. 2009.http://www.experiencebermuda.com/activities/bell-diving.html