# Sir Isaac Newton Part 2

In 1669 the plague receded. Cambridge comes to life again, and Newton was appointed Professor of mathematics. At that time, under the mathematical Sciences was implied also geometry, astronomy, geography and optics, but the lectures Newton was considered boring and not in demand of students — often he had to speak to empty benches.

## Flying Apple

The conventional (and most likely) version is that in the summer of 1666 Newton, wandering around the garden of his estate in Woolsthorpe once intellectual trance, saw the tree falling ripe Apple. Another, more anecdotal legend, an Apple fell on his head. Anyway, Newton got to thinking: what if the gravitational force acts not only on objects near the Earth but much farther it — for example, on the moon and other celestial bodies?

When one day, immersed in thought,

Newton saw the Apple fall,

He brought the law of attraction

From this simple observation.

For the first time from Adam’s times

On Apple’s reasonable judgment

With the fall and with the law of the secret forces

The mortal logical mind agreed.

George Gordon Byron, “Don Juan”

Stone Apple at the feet of the statue of Newton (Oxford Museum of natural history).

Previously, the clergy was offered an alternative “theory of gravity” — say, a person’s pull to the ground his sins. Repent can go to heaven, to heaven, and the wicked, respectively, falls to the ground in hell.

However, in the 17th century the Church had already abandoned the main methods of competition with science — torture, and fires, so the scientists boldly forward an alternative version. Descartes wrote that gravitation is the result of vortices in the ether, but Kepler believed that it extends only in the plane of the Ecliptic.

Newton linked the law of gravity (force is inversely proportional to the square of the distance) and explained the nature of planetary motion. Before the theory of relativity, any amendments to this model were not. The famous thought experiment of Newton with a gun (if you put it on the highest mountain, to aim horizontally and fire the ball at a certain speed, it will orbit Earth like the moon) actually laid the first stone in the Foundation of Astronautics.

The scientist also explained the tides by the attraction of the moon and, with the elevation of the arriving water, calculated the mass of the satellite of our planet.

Newton linked the law of gravity (force is inversely proportional to the square of the distance) and explained the nature of planetary motion. Before the theory of relativity, any amendments to this model were not. The famous thought experiment of Newton with a gun (if you put it on the highest mountain, to aim horizontally and fire the ball at a certain speed, it will orbit Earth like the moon) actually laid the first stone in the Foundation of Astronautics.

The scientist also explained the tides by the attraction of the moon and, with the elevation of the arriving water, calculated the mass of the satellite of our planet.

The light of reason

In December 1671, Newton became a candidate member of the Royal scientific society, founded ten years earlier. It was an elite organization of geniuses, the Freemasons, and alchemists who were interested in all kinds of knowledge, including occult.

### The building of the Royal society

In January 1672 Isaac read to members of the society a report on optics and has demonstrated he built a reflecting telescope. Used telescopes-refractors gave noticeable chromatic aberration. The reflector was free of these disadvantages (reflecting telescopes used so far).

According to the results of the report, Newton was immediately admitted to the society. He is flattered and he decided to share with colleagues the kind of “great philosophical discovery.” It was the theory of light: white color consists of the full range of colors and objects appear colored because they absorb some colors better than others.

To understand the importance of this discovery need to know that a single optical theory at the time was not yet. Someone thought that the color obtained from the mixing of light and darkness in varying proportions, Descartes believed that the colors created by different speeds of light particles. Using a glass prism Newton proved members of society that white light is not primary, and consists of a basic (non-biodegradable other components) at different angles of refraction.

Newton is very sensitive about criticism. His optical researchers were attacked by Robert Hooke. According to legend, in 1689 exasperated Newton vowed to stop the study as long as his opponent doesn’t die. It occurred in 1703.

A year later he published the fundamental monograph of Newton’s “Optics”, which, in addition to revolutionary calculations for dispersion, interference, diffraction, and polarization of light argued that light consists of tiny particles — corpuscles. This error is long lived due to the authority of Newton.

### The burden of fame

A portrait of Newton the work of Keller. As noted previously, Newton was reluctant to publish his work, preferring to discuss certain issues in correspondence with colleagues. In 1682 near Earth was comet Halley, which caused a surge of interest in the interaction of celestial bodies.

The Halley asked Newton to compile and publish all his research in physics in a single work. The decisive argument was the money. Newton had trouble with finances, therefore it is even freed from dues to the Royal society. Financing the publication of Newton’s Magnum Opus took up Halley.

The work was published in 1686 under the title “Mathematical principles of natural philosophy” (physics). The book, detailing — no more, no less — the basic laws of nature, was sold out for 4 years and survived 3 reissues during the life of the author.

All academic Europe stood on the ears. Some researchers literally worshiped Newton, others called him a charlatan. Invisible and intangible gravity was represented by something like magic, and Newton himself could not explain its origin (and even admitted that gravity is supernatural).

A portrait of Newton the work by Keller

Newton instantly became a national hero. The pace of life has accelerated several times. In 1689 he was elected member of Parliament, but all that was left of his MP — written complaints of draughts in the courtroom. The most famous artist of the country — sir Godfrey Keller draws the first portrait of Newton.

Then Isaac meets 25-year-old Swiss mathematician Nicolas de Dule. They begin a close relationship. Many noted that perhaps even too close. A romantic mood Newton attempted to provide himself and his friend the future, seeking government positions. But in the “black” 1691 it suffered a series of misfortunes.

The death of his old friend Professor Babington. Half-sister Anna lost her husband and was left without a livelihood. In the house of Isaac was a fire that destroyed rough notes “Mathematical principles”, which deprived Newton of the arguments in a dispute over priority in the discovery (at that time, scientists were actively communicated, shared ideas and many theories have developed, in fact, collectively).

Finally, young de Dulle escapes from Newton in Switzerland (allegedly because of a bad climate of England). These shocks were so strong that Isaac came temporary insanity.

In 1695 Chancellor of the exchequer Charles Montague, a former student of Newton had invited a scientist to the post of warden of the mint with a yearly salary of £600. Newton, due to the lack of material recognition of his services, agreed to move to London.

22/08/2017