Leonardo da Vinci, finding many fossils in canal building sites, proposes that fossil shells of marine animals are found on mountains because Earth undergoes transformations that cause areas once submerged to become exposed.
Hieronymus Brunschwygk's Liber de arte distillandi de simplicibus, known as the "Small Book (of Distillation)", describes medicinal herbs and the construction of stills for processing them.[2][3] He will publish his "Big Book", dealing with the same subjects, in 1512.
Leonardo da Vinci draws a wheel-lock musket, the first known appearance of this type of ignition, in which a spring mechanism causes a ratchet to strike sparks from iron and pyrites or flint. It will come into use, replacing match ignition, about 15 years later. By this date, he has also designed the first helicopter (although it is probably unworkable).[4]