invention, mathematics, music, painting and sculpture are still revered and relevant today. Da Vinci's ideas involved inventions not technically feasible until the twentieth century, and include tanks, helicopters, parachutes and countless others. This eBook contains his complete notes, Volumes I and II, and contains the original plans for what Brown describes as the cryptex. For thirty years, the whole last half of his life, Leonardo da Vinci was obsessed with unlocking the secrets of nature. His notebooks are the mind-boggling evidence of a fifteenth-century scientist standing at the edge of the modern world, basing his ideas on observation and experimentation. A singular fatality has ruled the destiny of nearly all the most famous of Leonardo da Vinci's works. Two of the three most important were never completed, obstacles having arisen during his life-time..