In November 1994, Bill Gates purchased 18 sheets of Leonardo da Vinci’s notebooks for $30.8 million. da Vinci’s notebooks included original plans and ideas for a flying machine, a helicopter, a parachute, the extendible ladder, three-speed gear shift, the bicycle, adjustable spanners, the snorkel, hydraulic jacks, locks for canal systems, folding furniture, a water-powered alarm clock and