Sunday, March 6, 2016
Leonardo Da Vinci's Ship's Cannon With Shield
From the Instructions "
Leonardo da Vinci was also a military engineer; he studied weapons and medieval military techniques at length. A large part of his manuscripts show machines and military architecture, some are copies of machines by Taccola Francesco di Giorgio, others are his own inventions or modifications of existing machines. He also spent a lot of time working on naval battles, designing dozens of ships with as many attacking methods as means of defense on the sea. One of the most original projects is that of the ship with shield and cannon. Da Vinci drew this naval weapon in manuscript B for the first time, almost certainly copying it from a previous author, because the drawing of this project was already presented in the treatises of engineers who came before da Vinci and to whom he referred when studying. Again, it was a general idea, only roughly drawn and without any technical details. Da Vinci subsequently revisited the project; he reconsidered it, improved it and redrew it clearly and in its entirety on folio 172r of the Codex Atlanticus. The idea was to use a small, agile vessel equipped with a cannon. The prow of the ship and the cannon are protected by a wooden shield. Da Vinci studied this subject closely, identified the weak points and invented his own version with many more functions. He transformed the almost "fantastic" medieval drawing into a truly achievable engineering project. First, he concentrated on the structure of the vessel which needed to be reinforced and keep the cannon firmly in the middle. The shield, which previous engineers had shown as being immobile and almost temporary, in da Vinci's drawing was split in two and became part of the structure and mobile. A system of ropes and pulleys keeps the shields raised to protect the ship. Once the winches are locked, the weight of the shields themselves causes them to rotate outwards to uncover the cannon which can then fire. The shield rotate on two non-parallel axes and da Vinci designed a geometric shape of them so that when lowered, they fit around the curve of the ship. The resulting contact between hull and shield is not an easy line to calculate and da Vinci proposed a few variations. Firing the cannon is another problem to deal with, as this causes a recoil powerful enough to push the ship backwards. The semi-submerged shields themselves act as breaks, keeping the ship steady as it fires. Da Vinci's drawing on folio 172r even shows the metal covered prow of the ship with a detail showing the device that attaches the shield hinges. The metal covered prow is there to deliver the first blow to the enemy and is therefore a secondary weapon. The shields are not just to protect the prow, but also to hide the main weapon: the cannon. The ship could therefore approach the enemy quickly, and its tapered and futuristic shape made it also rather menacing. It was protected by a shield which made the cannon invisible and meant that enemy weapons would be ineffective work. The angle of the shield was also useful to deflect cannon fire. When rammed quickly into the enemy, it could create the first serious damage thanks to its metal covered prow. Once the enemy ship was "hooked' and presumably a breach had been created in the hull, it was the moment to unveil the secret weapon. The shields having been quickly lowered thanks to their own weight, the cannon was ready to fire directly into the enemy ship. In theory, a small vessel such as this could therefore sink a large galleon. It is not known whether a ship like this was ever built. There are no records of it and perhaps this project too remained amongst the many projects that Leonardo da Vinci never carried out.