I am currently re-watching a TV show 'Da Vinci's Demons'. The show is a fictional historical account of the early years of Leonardo da Vinci while he was just a young, troublesome artist and engineer. Da Vinci approached the ruler of Florence at that time, Lorenzo di Medici, and asked for the position of Military Engineer. Lorenzo agreed and appointed da Vinci. Da Vinci's job was to create military weapons for Florence as Rome was planning to attack them in war. Da Vinci proposed a three-stepped canon which would fire in quick succession. If you are well versed in history you would know that da Vinci's dream was almost an impossibility. I mean, we are talking about the 13th century when there was little technological advancement. However, despite the cynicism of everyone around him, save for his close friends, da Vinci embarked on the journey. He was finally able to produce the canon. However, at the first testing, the canon exploded, almost killing him and the royal entourage that came with Lorenzo. This made Lorenzo angry, giving da Vinci a 3-day deadline to put it right if not, he would be hanged.