The eccentric engineer
A desire to know what lies beneath the surface of the sea has led to ingenious ways to travel underwater.
Engineers are a practical bunch, and I surely can't be the only person to have thought of combating the melting of the ice caps by building a submarine. If it's not exactly a long-term solution, it might at least give greater minds a bit longer to think about one.
The first record of anyone wanting to know what lay at the bottom of the sea comes from Aristotle who claims to have seen divers placing cauldrons over their head, so they could reach the seabed, although he doesn't say why.
Viking sailors had a practical interest in knowing what lies beneath, as this sometimes came up to meet them rather suddenly in the form of reefs and rocks. To avoid these dangers, they invented the sounding weight - a lead cylinder with a hollowed out end filled with something sticky, like beeswax. The weight was attached to a line and dropped overboard. When it hit the bottom, the rope could be hauled in, the depth being measured by counting the number of arm-spans of rope pulled up. That 'arm span of an average sailor' became a standardised measurement of six foot, or one fathom, as sailors called it. The wax on the end of the weight was useful as, by looking at what stuck to it, you could get an idea of what the bottom was made of. This helped with choosing good anchorages and preventing raiding parties ending up high and dry on the rocks at low tide and hence outstaying their welcome.
Despite all this innovation, ships continued to sink, and it was a desire to recover the spoils that inspired the first true diving machines. One of the first to give it a whirl was Leonardo 'Try Anything Once' Da Vinci, who drew up plans for a diving helmet, complete with spikes to protect the wearer from the 'monsters of the deep'. Like with so many of his inventions, however, there is no evidence he ever built one.
The first person to think about how to explore the undersea realm properly was the British mathematician William Bourne, who in 1578 produced plans for a submersible enclosed rowing boat. Cornelius Jacobzoon Van Drebbel, a Dutchman working for the British navy, actually got as far as building one, and is usually credited with having invented the submarine.
Van Drebbel had an interesting but ultimately unfulfilling life at various European courts. An engraver by trade, his passion for inventions first brought him to the attention of royalty when he invented a self-winding clock which operated by changes in air pressure. King James I of England thought this was a perpetual motion machine and appointed him 'mechanic to the Prince of Wales', charged with arranging suitably elaborate firework displays and other entertain-ments for the Prince. The Emperor Rudolph II went one stage further and declared it to be magic, appointing Drebbel 'chief alchemist'. Life at the Prague court was not pleasant, however, particularly after Rudolph went mad, was deposed and Drebbel (for fear of his alchemical powers) was flung into prison. On being released, he returned to England where he swapped alchemy for the less dangerous work of inventing microscopes, devising one of the very first feedback-controlled devices (a chicken incubator whose temperature was controlled by a mercury thermostat), creating a new scarlet dye and building the first submarines.
His early submarine was actually a form of Bourne's underwater rowing-boat, consisting of a greased leather-clad barrel, with oars sticking out of either side - the rowlocks being sealed with leather flaps. When submerged, the proud owner of a 'Van Drebbel' then had to row with considerable force, not only to move forward but to dive and surface. Tests were undertaken with the sub in the Thames between 1620 and 1624 in three successively larger vessels - the final leviathan having six oars and 12 rowers.
Quite astonishingly, the Van Drebbel submersible did work and managed to operate at depths of up to 15 feet for several hours at a time, cruising from Westminster to Greenwich. So impressed was King James I that he is reported to have taken a trip in one of Drebbel's later models, which, if true, would make him the first monarch to have travelled (voluntarily) underwater.
So, at last, Van Drebbel had a success on his hands? Sadly not. The King might have liked the idea, but so unimpressed was the British navy that they cancelled the project, turning their backs on one of the most important naval vessels of all time - at least for now. This was despite the predictions of the Bishop of Chester - who was a very clever man and the only person ever to be master of colleges at Oxford and Cambridge - who pointed out in his 1648 book 'Mathematicall Magicke' that:
"Tis private: a man may thus go to any coast in the world invisibly, without discovery or prevented in his journey... It may be of great advantages against a Navy of enemies, who by this may be undermined in the water and blown up."
But the navy knew best, and Drebbel and his great idea were forgotten. After an unsuccessful attempt to blow up La Rochelle harbour on behalf of the British Navy, Drebbel fell into disgrace and ended his days as a penniless ale-house keeper. Despite this, there is crater on the moon named after him. There are no craters named after James I or Rudolph II.