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GREEKS TO BELLS - REG VALLINTINE
More recently, 500BC, is the story of Scyillias and his daughter Cyana. They were Greek divers who worked recovering treasure for the Persian king Xerxes, breath holding. Xerxes wouldn’t let them return to their country, and so seizing an opportunity they found his fleet in difficulty, cut the anchors underwater and caused a great catastrophe. Cyana was undoubtedly the first woman diver.
Around 1500 Leonardo da Vinci started filling his notebooks with designs for diving equipment: these included shallow water snorkel tubes, strange helmets with spikes to repel fish and divers with large bags that looked like sandbags which were intended to contain air.
Even before this Alexander the Great allegedly had descended in a glass diving bell illustrated here with a strange collection of unknown animals and candles inside.
332 BC
The problem with diving bells, that were essentially bucket shaped objects pushed down into the sea, rim first and trapping air inside, was firstly that if they left the divers there too long they wouldn’t have enough air to breathe and secondly that they were breathing out into the bell and so there was a build-up of carbon dioxide.
By 1690 Edmund Halley of the Royal Society had produced a bell which overcame a lot of these difficulties. Basically at the top he had a sheet of glass and so that there was light in the bell. When the divers were on the bottom he let down, after a certain time, barrels of air, fresh air. The divers could then get these barrels and upturn them inside the bell, refreshing the air. The bell also has a weight at the bottom to keep it upright. And you can see that with these bells the diver could swim outside on an umbilical to put a line on a cannon or some other object which could then be pulled up to the surface afterwards.
John Smeaton who built the third Eddystone Lighthouse also produced the first really modern diving bell.
1788
Over the following centuries a number of designs were produced: some of which I am sure never got off the drawing board. Loreni, 1597, a remarkable longbored tube with the diver sitting thoughtfully at the bottom, presumably waiting to catch a fish in his hands. He looks a bit squashed, but hasn’t suffered like the occupant of Kestler’s Bell here. I think that’s a weight, but we’re not quite sure. It could be a nasty physiological effect.
BARRELS & HELMETS- REG VALLINTINE
A really successful device though in 1715, produced by John Lethbridge, from Devon (who had 17 children to support) in the shape of a barrel. A wooden hogshead from which his arms hung out into the sea. Problems here were that there was more pressure on his arms than on his body which was basically at atmospheric pressure. In spite of this he could use it down to 60 feet and was commissioned by the Dutch East India Company and went round the world recovering gold and goodies from all sorts of wrecks.
5 years later Captain Jacob Rowe patented a design for another diving machine or barrel; shaped like a Scotch snuff mill. He used it successfully to recover gold from a Dutch East India man off Barrow in the Hebrides.
During the following centuries a number of designs for diving helmets were produced, including this one by Klingert in 1797. This one was actually quite successful in that he managed to saw up a plank of wood under the river Oder. But generally the technology was not well enough developed. Although John Braithwaite, another Englishman, had successfully salvaged from the Earl of Abergavenny.
Conventional history then tells us that suddenly at the beginning of the nineteenth century an engineer called Augustus Siebe produced a virtually perfect design for a diving helmet.
AUGUSTUS SIEBE (1788-1872)
Very recent research by Alexander Mackee and John Bevan has in fact shown that it was another Englishman who produced this design, Charles Deane who was virtually unknown before that time.
CHARLES DEANE (1796-1848)
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