Because there was no market for largely speculative drawings of ideas for mechanical devices, most of which were not practical and many of which were little more than doodles. Despite his modern reputation as a "scientist" (which he was not), Leonardo worked within the late medieval tradition of the artisan. read more
The imagination and thinking capability Leonardo da Vinci had was far more advanced of his time. As a military engineer me made plans for weapons like armored tank, machine gun, mortar,guided missile, and submarine which deployed hundred yearn from then. read more
There wasn't a scientific community. There was no printing press. There were only monks copying out texts, religious texts mostly, by hand. read more
We tend to think of Leonardo da Vinci as a painter, even though he probably produced no more than 20 pictures before his death in 1519. Yet for long periods of his career, which lasted for nearly half a century, he was engrossed in all sorts of surprising pursuits, from stargazing and designing ingenious weaponry to overseeing a complex system of canals for Ludovico Maria Sforza, the ruling duke of Milan. read more