Isaac Newton: Newton's Scientific Discoveries

Newton's Incredible Scientific Discoveries: Myth, Inspiration and Technology


On a warm evening in 1666, just after dinner, the soon to be famous Isaac Newton sat down beneath this tree outside of Trinity to mull over his thoughts, when all of a sudden he was struck on the top of his head by a large, red apple. ‘Eureka’, he cried, and Gravity was discovered. As entertaining as this tale is, Newton was not struck on the head by an apple and he was not underneath this tree. In fact, no such tree existed in Cambridge at the time. But in just half a century, this grand myth was woven by his admirers from its original simple story.  This tree is a grafted descendant of the original one at the home of Sir Isaac Newton's mother in Woolsthrope, Lincolnshire. On a visit to his mother's garden during his Cambridge days in the late 1660s, he observed a green apple fall from a tree and only then began to consider the mechanism that drove what is now termed Gravity.

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When Was Newton Born?

Isaac Newton, regarded as one of the most influential scientists of all time was actually born on Christmas Day 1642, despite it being converted to January 4th in the New Style (modern) calendar, which had not been adopted in England yet. He was subsequently baptised on New Year’s Day.

The Theory of Universal Gravity

As the legend goes, a young Isaac Newton was sitting beneath an apple tree contemplating the mysterious universe when suddenly an apple hit him on the head at which point he realised that the same force causing the apple to fall kept the moon falling towards the Earth and the Earth falling towards the sun: ‘Eureka.’ Descendants of the original tree can be found in Cambridge and a piece of the original was even loaned by the Royal Society to NASA who took it into space! 

Commomorative Apple Tree at Trinity College, Cambridge

Weight is the force of gravity on an object so if you weigh 100 pounds on Earth, you only weigh 38 pounds on Mars because it has less gravity. An interesting fact is that the gravity of the moon causes ocean tides!

 The Falling Apple and Discovering Gravity- What really happened?

Isaac Newton, never kept any record of what happened that fateful day in the late 1660s when he was inspired by an apple falling from a tree. Therefore, there exist numerous accounts from his acquaintances and admirers—each recounting a different experience.

John Conduitt's Account

The earliest of these accounts was recorded in 1726 in the notes of John Conduitt, a Cambridge student. In this year of Newton's death, Conduitt wrote, ‘the first thought of his system of gravitation which he hit upon by observing an apple fall from a tree.’ He didn't specify which tree or where the apple fell. Only a year later, Voltaire used his artistic license to parade Newton's magnanimous discovery, in his Essay on Epic Poetry (1727), ‘Sir Isaac Newton walking in his gardens, had the first thought of his system of gravitation, upon seeing an apple falling from a tree.’ Again, Voltaire didn't specify how the apple fell, but specified his gardens in Lincolnshire.

William Stukely's Account

One of the most reputed accounts of Newton and the apple is in William Stukely's Memoirs of Sir Isaac Newton's Life (1752). Stukely was a good friend of Newton's and a scholar of archaeology. He recalled, 'After dinner, the weather being warm, we went into the garden, and drank tea under the shade of some apple trees, only he, and myself. Amidst other discourse, he told me, he was just in the same situation, as when formerly, the notion of gravitation came into his mind. "Why should that apple always descend perpendicularly to the ground," thought he to himself: Occasion'd by the fall of an apple, as he sat in a contemplative mood: "Why should it not go sideways, or upwards? But constantly to the earths centre? Assuredly, the reason is, that the earth draws it. There must be a drawing power in matter. And, the sum of the drawing power in the matter of the earth must be in the earth’s center, not in any side of the earth. Therefore dos this apple fall perpendicularly, or toward the center. If matter thus draws matter; it must be in proportion of its quantity. Therefore the apple draws the earth, as well as the earth draws the apple."

So where is this famous tree?  

The tree described in Stukely's account, still exists today! It is over 350 years old, and is protected by the National Trust.

After the death of Newton's mother in 1679, her property was soon acquired by the Woolerton family, who were tenant farmers. The family cared for both the tree and the house from the 1750s until 1947.  In 1816, the tree was blown over in a storm, but successfully re-rooted, where it still stands today.

 The Newton Apple Tree at Trinity College, was grafted from the original tree and planted in 1954. The tree is of the Flower of Kent variety, which doesn’t produce apples for eating, but cooking apples which are green, not red (as in the original story). 

So why did this myth evolve?

In an interview with the Independent, Royal Society head archivist, Keith Moore explained, 'The story was certainly true, but let's say it got better with the telling." The story of the apple fitted with the idea of an Earth-shaped object being attracted to the Earth. It also had a resonance with the Biblical account of the tree of knowledge, and Newton was known to have extreme religious views'. 

Newton’s Theory of Light

Isaac Newton was the first scientist to discover that light is made up of particles, not waves, in an experiment using two glass prisms. His findings led him to conclude that light is composed of coloured particles that combine to appear white. So now when you see white light, you can imagine that it is actually made up of lots of different coloured particles including red, orange, yellow, green, blue, indigo, and violet. Now look out for rainbows because the water droplets (rain) and sunlight act in the same way as the glass prisms and white light to create those wonderful seven colours. Newton is said to have bought his prisms from Stourbridge Fair in Cambridge, which he used to conduct his experiments.

First Functioning Telescope

Photograph Andrew Dunn, 5 November 2004

Isaac Newton’s reflecting telescope, 1668  

Photograph © Andrew Dunn, 5 November 2004

Scientists had struggled for years with building an effective telescope because they used a glass lens which distorted the picture quality due to white light being split into colours. Newton replaced the lens with a metal mirror which reflected a lot more light and consequently gave a better view of the sky.

The Philosopher’s Stone

Harry Potter and the Philosopher's Book Cover 

Isaac Newton may not have known about Harry Potter, however, following his death it became apparent that he had written lots of papers on the Philosopher’s Stone. Newton was a firm believer in alchemy and one of his greatest ambitions was to gain the secret of turning common metals into gold. He was also interested in discovering an elixir of life.

Laboratory on Fire

Isaac Newton once told a story of how his dog set his laboratory on fire, ruining twenty years of research. When he saw what man’s best friend had done, Newton is said to have said. ‘O Diamond, Diamond, thou little knowest the mischief thou hast done.’ Some historians believe that a more likely story is that he left a window open and a gust of wind knocked over a lit candle. The story of the dog was merely an excuse for his own mistake!

Isaac Newton the farmer?

Newton’s mother expected her son to take over control of the estate his father had left behind having been a successful farming family. Isaac did try to fulfil his mother’s wishes, but his lack of interest in the subject meant he was a very poor farmer. Newton’s Uncle and Head teacher from school eventually managed to convince his mother to let him go to college.

Newton’s Tooth

Isaac Newton has the most valuable tooth of all time. One of his teeth was sold in 1816 at auction for approximately $3,600 or $35,000 in today’s terms!

Newton at Cambridge

Andrew Dunn 2004

Photograph © Andrew Dunn, 5 November 2004

Isaac Newton entered Trinity College in 1661 and acted as a sizar or servant for socially superior fellow-students or for tutors in order to pay for his university education. He further supported himself with a small money-lending operation. Newton was driven by the belief that the path to true knowledge lay in making observations rather than reading books. On one occasion, rather than trust books on optics, he experimented by sticking a bodkin – a blunt needle – in his eye to see its effect! He almost blinded himself.

Newton’s Bad Temper

Isaac had a very bad temper and became particularly angry with Robert Hooke who was also part of the Royal Society because he accused Newton of stealing his ideas on the laws of gravity. By the time of Hooke’s death, Newton was president of the Royal Society and he had all of Hooke’s portraits destroyed!

The Philosophiae Naturalis Principia Mathematica

Newton’s studies culminated in this famous publication regarded as one the most influential books of all time. It took Newton two years to write and it represented a combination of more than 20 years of thinking – it outlined his own theory of calculus, the three laws of motion and his theory of universal gravitation. This provided a new revolutionary mathematical description of the Universe, one that is still being used today. Einstein regarded Isaac Newton as one of the best people to have lived.

Tributes and Memories of Newton in Cambridge

In Trinity College there are five portraits of Newton, a commemorative apple tree and a famous statue of him, which can be seen in the Chapel.    

Newton Statue- Trinity

Statue of Isaac Newton by Louis-François Roubiliac in Trinity College Chapel, Cambridge

 Photograph © Vygosky 22 July 2014

The Wren Library at Trinity College contains the largest intact portion of Newton’s library, and some papers which can be viewed by appointment. Also contains a display of Newtown memorabilia including walking sticks, watches, mathematical instruments and a lock of hair.

Andrew Dunn 2004

Photograph © Andrew Dunn, 5 November 2004

The most complete collection of Newton’s scientific papers can be found in Cambridge University Library and some of his work and one of his portraits can be seen at the University Library's 'Lines of Thought' exhibition from March-September 2016.

The Whipple Museum contains a replica Newtonian reflecting telescope and a number of portraits of Newton.

For more information about visiting these places see the Discover More section below. 


 Sir Isaac Newton -Copyright 1997 David Arns 

 Under a spreading apple tree,
     The village genius stands;
His mind conceives of wondrous things,
     He writes them with his hands;
His fame goes forth to all the world--
     He's known in many lands.

 A tiny babe on Christmas Day
     in 1642
Was born to Mrs. Newton
     while outside, the cold winds blew.
And on the farm, through childhood,
     precocious Isaac grew.

And after chores, he built devices
    to see just how they worked,
To see what laws of nature
     underneath the workings lurked.
(When people called them "toys," that's what
     got Isaac really irked.)

His mother saw he was no farmer,
    sent him off to school;
He quickly showed at Cambridge
     that he was nobody's fool:
He began to bring to light the laws
     that all of nature rule.

In one chapter in his story
     (though apocryphal, it's said),
An apple, falling from a tree
     impacted on his head,
Which drew his thoughts to gravity,
     and we all know where that led.

  He wondered if, by any chance,
    the self-same gravitation
That pulls an apple to the ground,
     affected all creation:
The moon, the planets, and the sun. . .
     Thus went his cogitation.

  He determined that the gravity
    of earth indeed controls
The orbit of our moon, as 'round
     the earth it ever rolls.
Now, describing it mathematically
     was one of Newton's goals.

 He discovered that the math you need
    to show the laws of nature,
Surpassed the knowledge of that day;
     the cosmos' legislature
Required new math, so Newton wrote
     his "fluxions" nomenclature.

He talked of falling bodies
     and his famous Laws of Motion,
And of colors seen in bubbles
     and the tides upon the ocean.
And his crowning jewel, "Principia,"
     created great commotion.

  Yes, Newton's brilliant mind, it was
     a trunk with many twigs--
His mind branched out in every way
     (right through his powdered wigs).
His greatest contribution, though,
     was cookies made from figs.


Discover More


Trinity College, Cambridge, CB2 1TQ

Where you can find Newtonian items in Cambridge:

Wren Library- Trinity College:

The Wren Library contains the largest intact portion of Newton’s library, and some papers which can be viewed by appointment. Also contains a display of Newtown memorabilia including walking sticks, watches, mathematical instruments and a lock of hair.

Cambridge University Library:

The most complete collection of Newton’s scientific papers can be found in Cambridge University Library.

The Whipple Museum- The History of Science Museum:

The Whipple Museum contains a replica Newtonian reflecting telescope, and a number of portraits of Newton.


BBC iwonder Newton page:

Issac Newton Institute:

Isaac Newton: Newton's Scientific Discoveries


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