Giovanni Fontana, also known as Johannes de Fontana (ca. 1395 – ca. 1455) was a fifteenth-century Italian physician and engineer. He was born in Venice in the 1390s and attended the University of Padua, where he received his degree in arts in 1418 and his degree in medicine in 1421. University records list him as "Master John, son of Michael de la Fontana". His most famous promoter at the university was the scholastic Paul of Venice. He tells us that the Doge of Venice sent him to Brescia to deliver a message to the condottiere Francesco Carmagnola. He was also employed as the municipal physician by the city of Udine. Works Fontana composed treatises on a diverse array of topics, including measurement of heights or depths by falling stones. We have early works of his on water-clocks (with wheels), sand-clocks and measurement. Fontana studied trigonometric measurements, mentioned in De trigono balistario, and through his own designed instrument, also explained in a larger treatise, however, apparently lost. He wrote a treatise on perspective, and showed it to the painter Jacopo Bellini. Grafton notes "Modern scholars often note that early engineers did not supply formal working drawings of their devices, but represented them in real time, functioning, in a way that did not give away their secrets but could appeal to patrons. Fontana, however, makes a superb exception to this rule. ... He drew not only male and female devils inspiring terror in real time by their fearsome appendages, but also the underlying mechanisms, which he laid out with the abstracting brilliance of a fifteenth-century Giacometti or Max Ernst. ... Fontana insisted that he was no magus. When witnesses at Padua exclaimed that a torpedo he had designed must run by diabolic power, he refuted them with contempt: the device was purely mechanical, as befitted a maker who was also a master of both medieval Archimedean statics and optics and of Renaissance engineering craft." Bellicorum instrumentorum liber Fontana composed one of the earliest Renaissance technological treatises, Bellicorum instrumentorum liber. His machine book contains siege engines and fantastic inventions such as a magic lantern and a rocket-propelled bird, fish, and rabbit. Fontana also built a 4-wheeled "bike" with rope connected by gears. It is not technically a bike, but 400 years after 1418, Baron Von Drais built a two-wheeled bike that has a cord connected to the back wheel, so when you pull