The submarine has seen many incarnations in the last few centuries. Its technology has seen enormous innovation and been hugely groundbreaking since its conception in the Renaissance era. While first developed as a simple method of underwater exploration it was transformed over time into one of the most powerful warfare weapons ever. The concept of submarine technology had humble beginnings with simple diving bells being used but in the coming centuries we would see the development of an array of different submarines from basic wood crafts to today’s nuclear fleets.
The diving bell could be considered one of the most primitive types of technology in the vein of the submarine. The diving bell was an enclosed structure which retained air when submerged underwater enabling people to enter it and submerge themselves also. One of the earliest accounts of this technology was described by Aristotle in the 4th century BC. Of the diving bell he wrote: “they enable the divers to respire equally well by letting down a cauldron, for this does not fill with water, but retains the air, for it is forced straight down into the water."<1> While the idea of the diving bell was conceived over two-thousand years ago it was not until the Renaissance era that more sophisticated plans for underwater vessels began to develop. Throughout the era many physicists and inventors such as Guido da Vigevano and Roberto Valturio drafted plans for underwater technology. These plans however never materialised.
It wasn’t until 1578 that any detailed plans were made to produce a vehicle capable of being navigated underwater. Englishman William Bourne designed a prototype for what we would now call a submarine and published the designs in his book Inventions Or Devises. Bourne was a former naval gunner and after studying the science behind what makes a boat float on water he began thinking of mechanisms which would enable boats to sink and rise at will. His hypothesis was that decreasing the volume of a boat so that it is heavier than the water underneath it will make it sink while increasing the volume will make it float. While Bourne did not produce any sketches to go with his idea he did describe how the vessel should be made of wood covered in watertight leather and contain internal structures which enabled its volume to increase or decrease in size.<2>
While Bourne only offered a principle for the submarine and no design plans. The first actual submarine was produced in 1620 by Cornelius Drebbel, a Dutch scientist in the court of James I. Drebbel’s submarine appeared as a decked-over rowboat, covered in leather with a rudder at the rear. The submarine was propelled by four oars which were controlled from the inside. A watertight hatch on top of the vessel enabled the oarsmen to enter it. Drebbel’s method for raising and sinking the boat involved using pigs’ bladders connected by pipes to the external water. Ropes were tied around the bladders. When the crew wanted to submerge...