In 1482, Florentine ruler Lorenzo de' Medici commissioned da Vinci to create a silver lyre and bring it as a peace gesture to Ludovico Sforza, who ruled Milan as its regent. After doing so, da Vinci lobbied Ludovico for a job and sent the future Duke of Milan a letter that barely mentioned his considerable talents as an artist and instead touted his more marketable skills as a military engineer. Using his inventive mind, da Vinci sketched war machines such as a war chariot with scythe blades mounted on the sides, an armored tank propelled by two men cranking a shaft and even an enormous crossbow that required a small army of men to operate. The letter worked, and Ludovico brought da Vinci to Milan for a tenure that would last 17 years.
His ability to be employed by the Sforza clan as an architecture an