When talking about scientists who have explored gravity, surely the first name that comes to mind is Albert Einstein, but many centuries before even Isaac Newton himself began to explore the concept of gravity, polymath Leonardo da Vinci had already discovered the most important key to gravitational behavior.
Leonardo Da Vinci and his Curiosity About Gravity
You may know Leonardo da Vinci for his great contributions to art and the invention of scientific devices, but not necessarily for exploring gravity. This is because it was not known that the Florentine polymath had ventured into such difficult terrain, until now when aerospace and medical engineering professor Mory Gharib discovered an abandoned codex written by Da Vinci.
The concept of gravity was not explored in history until Galileo Galilei conducted his famous hypothetical experiment on the free fall of two objects with different masses from a great height in 1604. It was not until the end of the century that Isaac Newton developed his theories on gravity, which dominated classical physics until they were overthrown by Albert Einstein’s General Theory of Relativity in 1915.
But even before all of this happened, and before the very name ‘gravity’ existed, Leonardo da Vinci was already exploring the concept. This is suggested by Gharib and his research team in an article in the Leonardo journal, where they describe a series of drawings made by the famous scholar in the Codex Arundel.
‘Equatione di Moti’
While exploring the Codex Arundel, a collection of contributions to art and science written by Da Vinci, Gharib found a series of drawings that caught his attention. These are different triangles that describe the trajectory of water or sand particles coming out of a jar.
“What caught my attention was when he wrote ‘Equatione di Moti’ on the hypotenuse of one of his sketched triangles, which was an isosceles right triangle,” says Gharib, lead author of the Leonardo article. “I was interested in seeing what Leonardo meant by that phrase.”
Basically, what Da Vinci was portraying was an experiment in which a jug was moved along a straight path parallel to the ground, while at the same time pouring water or granular material, which is supposed to have been sand. The drawings make it clear that he was aware that the water or sand would not fall at a constant speed, but would accelerate. His notes also reflect that he understood the fact that the material stops accelerating horizontally once it is no longer influenced by the jug and begins to experience a purely downward acceleration due to gravity.
The article explains that “if the jug moves at a constant speed, the line created by the falling material is vertical, so no triangle is formed.” Instead, “if the launcher accelerates at a constant rate, the line created by the falling material forms a straight but inclined line that then forms a triangle.”
These triangles would be the ones that Da Vinci drew in his key diagram, and that would explain that if the motion of the launcher accelerates at the same rate that gravity accelerates, the falling material creates an equilateral triangle.
Gravity is an Acceleration
The key point discovered by Leonardo is that gravity behaves like an acceleration on falling bodies and not like a constant speed. This was an astonishing discovery considering that at the time of the polymath, this concept did not exist and had not even been vaguely explored.
Da Vinci was so astonishingly bold with his falling experiments that he modeled the gravitational constant with about 97% accuracy. However, he encountered the limitation of measuring instruments, as in his time there were no clocks precise enough to measure the time of fall. Perhaps for this reason, Leonardo was not able to translate his findings into mathematical equations, although he did try.
“We don’t know if da Vinci conducted more experiments or investigated this question more deeply,” says Gharib. “But the fact that he was dealing with this problem in this way, in the early 16th century, shows how advanced his thinking was,” he concludes.
Story originally published in Spanish in Ecoosfera.
