In 1499, when the French attacked, the duke lost his power. He fled Milan. Then, later on, he was captured. He died a prisoner in France.
In December of that year, Leonardo left Milan, too. Salai went with him. So did another old friend. Leonardo did not have a real home again for sixteen years. He took very little with him as he traveled from place to place. Only the most important things did he keep with him. Like his notebooks.
In Milan, he had started keeping notebooks full of drawings and ideas. Leonardo kept filling up notebooks for more than thirty years. His plan was to write an encyclopedia about everything.
Like the horse statue, this was another great big project. And like the horse statue, it was a job he never completed. However, the notebooks are still priceless treasures. The pages are illustrated with beautiful drawings of everything that had interested Leonardo. They are among the most beautiful drawings in the world.
There probably were a total of about thirteen thousand notebook pages. But after his death, many pages were torn out and sold. Some notebooks were cut apart; some disappeared. Some were rediscovered hundreds of years later. Today, there are ten different collections of Leonardo’s notebook pages. Only half the pages—about six thousand pages—are known to exist. They are in different places all over the world. There is always the hope that someday more notebook pages will turn up.
Bill Gates, the founder of Microsoft, bought one collection of pages. It is all about water. It is called Codex Atlanticus. Sometimes it is displayed in museums. In it are drawings of waves and currents, drawings of ripples in water, drawings of a drop of water as it splashes into a puddle. (Leonardo’s eyes were so sharp, he could see all by himself what today’s high-speed cameras can reveal.) There are experiments that Leonardo did with water.
In all the notebooks, his handwriting is reversed. This is called mirror writing. A mirror must be held up to the writing before it reads correctly. Why did Leonardo write this way? Nobody knows. He was left-handed. So maybe writing this way came most easily to him. Or he may have wanted to make it hard for anybody else to read the pages. Maybe he worried that other people might steal his ideas. Maybe he just wanted to keep his ideas secret.
Leonardo’s interest in water went all the way back to his childhood, from the storms he saw. But water was only one of the subjects he planned to cover in his encyclopedia.
He wanted to understand and explain light—what was it made of? He wanted to understand how eyesight works, why birds can fly, and all the different parts of the human body. He came up with a list of about twenty big subjects. Just one page of a notebook might have little drawings of bird wings and feathers, along with thoughts about music and ideas for new weapons or sketches on building dams. Leonardo never stuck to one subject. He’d go back and forth among many. The notebook pages are crammed with writing and beautiful drawings. It is almost as if whatever jumped into his mind, he put down on the page. What the notebooks reveal is the mind of a true genius.
Leonardo was interested in all kinds of machines. Machine parts interested him, too. Screws and hinges and joints and hooks and springs. It may be strange to think of a drawing of a door hinge as beautiful. But when Leonardo drew one, it was.
He wanted to invent vehicles for people to use on land, in the air, even underwater.
His design for a bicycle used a chain just like bikes do today.
He designed a parachute and something like a submarine.
One of his notebook drawings shows a flying machine with a rotor blade at the top. It was meant to twirl around and around. Like a helicopter.
Leonardo was sure that one day people would fly. He said, “It lies within the power of man to make this instrument.” The story is that Leonardo would go to the marketplace, where he would buy birds in cages. Then he’d bring them home and set them free. How did they flap their wings? What made them able to fly? Why were they able to land safely without breaking their legs? He longed to discover the answers.
He made lots of drawings of bird wings. And how feathers grew on wings. He studied bats, too. And he made drawings of their wings. He tried to make wings for people that worked by using pulleys, cranks, wheels, and shock absorbers. One drawing had a pair of back pedals and a hand crank to make the wings move. Using another pair, a person would have had to flap the wings using muscle power. The wings’ “bones” would be made of wood, the “muscles” from leather, and the “skin” from cloth.
Did Leonardo actually build any wings? Did anyone try them out? Nobody is sure. In the notebooks, he mentions testing the wings on a hill near Florence. If so, he may have jumped from the top of the hill and glided in the air for a little while. But he could not have flown. The wings would not have worked, for more than one reason. First, they were way too heavy. Also, it takes a lot of force to lift a heavy object off the ground and keep it in the air. The force of human power wasn’t strong enough. And in Leonardo’s day, engines with strong power had not yet been invented.
Of course, Leonardo was right. People did learn to make flying machines. But it didn’t happen until December of 1903. That is when the Wright brothers’ airplane flew for twelve seconds. That was almost four hundred years after Leonardo died. He was a man way ahead of his time.
For a while, Leonardo worked for another duke in Italy. His name was Cesare Borgia. He was power-hungry and bloodthirsty. Leonardo designed weapons for the duke’s troops to use in battle. Leonardo did not believe in war and referred to it as a disease.
But he did enjoy designing new and better war machinery. Some of the weapons look like something you’d see in a fantasy movie. There is one of a giant-size crossbow. It could shoot several arrows at one time. It was so big that several soldiers would have had to operate it. He also designed a strange contraption with long blades jutting out from it. It was supposed to strap onto a horse. The rider could attack his enemies, who couldn’t get close enough to hurt him.
Leonardo thought of the human body as a machine, too. In fact, he considered it the most perfect machine. Leonardo wanted to understand the human body in the same way he came to understand horses: inside and out. He wanted to figure out how all the different parts of the body worked together. The best way to do this was to dissect bodies. This means cutting into a dead body. Peeling back different layers reveals how the body is built.
Today, medical students learn about the body by doing dissections. Sometimes doctors do dissections to understand why a person died. But Leonardo’s time was very different. Medical students rarely ever did a dissection. They learned from books instead. The work of cutting into a dead body was considered too horrible.
Leonardo, however, was determined to see for himself. When he lived in Milan he had done some dissections of bodies. He wasn’t a doctor or a medical student, so what he was doing was illegal. Later in his life he returned to Florence several times. There again he did more dissections. It is believed he worked on about thirty bodies. What he learned from them was put down in his notebooks. The drawings he did of the human body are astounding.
In Florence, he had a workshop in a hospital. He worked at night and he worked alone. The work was indeed disgusting. He hated it. But he did it, anyway.
The drawings were not discovered until long after Leonardo died. Nothing like them had ever been seen before. The drawings of a foot, for example, show it from three sides, moving in different ways. Leonardo also did cutaway drawings. He would draw a foot where one part had no skin. This was to let the muscles underneath show through.
He’d draw muscles to look like strings or ropes.
This was a good way to show which way a muscle pulled a limb. He’d also leave out some of the muscle to show the bones. With these drawings, there is no need for words. The drawings are better than words. They show everything exactly as it appears.
If the body was a machine, then it should be possible to build a mechanical man. In 1495, Leonardo made a design for the first robot. There is some evidence that he built it, too. His robot was a full-size knight in armor that could sit up, move its head, and wave its arms. Again, Leonardo was hundreds of years ahead of his time. |