Leonardo da Vinci, however, focused his attention not on the fine arts, but on the natural sciences. More than 10,000 sheets of paper with notes were created in the course of his work, giving deep insights into the thinking of the great master. Above all, it was the desire to fly that had impressed him. Therefore, he meticulously examined the wing characteristics of bats and birds, the curvature of the wings, the density and arrangement of the feathers and the number of beats within a certain period of time. At nights he locked himself in his workshop to redevelop the possibilities of human flight. Countless sketches and models of flying machines were created. Leonardo da Vinci not only considered materials and technologies that were known at the time, but he also considered possibilities that would only be realized 400 years later. Leonardo da Vinci always proceeded very precisely with his recordings, as for example with the following description of a parachute.
It is hardly possible to name everything that Leonardo da Vinci had done and researched during his life. Besides the desire to fly, he was particularly interested in the human body. He wanted to know how man is built, how his limbs, muscles and joints function. He examined, dissected, experimented and recorded what he discovered. He even poured hot wax into body cavities of corpses to determine their shape. He discovered the curvature of the spine and was the first to draw the human fetus in the womb in the right position.
He also revolutionized painting. He invented the so-called Sfumato technique. This is a soft painting. Here we work tone-in-tone and therefore the hard contours are dissolved and the bodies look like modeled from light. In his research, he also discovered the laws of leverage, the parallelogram of forces, the dependence of friction on pressure and surface structure and designed the turbine wheel, which is still in use today.
From his self-representations we know today that he had a peculiar, reserved and profound character. As a rich but completely selfless man, he was extremely generous to his friends. These friends also described him as a passionate man, driven by an insatiable curiosity to discover and explore new things.
It is particularly remarkable that Leonardo da Vinci lived as a strict vegetarian and abhorred meat. At that time it was unthinkable, because the possibility to eat meat was reserved for the upper class, who usually enjoyed this privilege extensively. Since Leonardo found the killing of animals unfair, he refused this privilege. It is even reported that he bought animals at the market to give them freedom afterwards.