The Secret Museum

But Newton knew the value of a good anecdote and told it himself. In the Royal Society library there is a first-hand account of him describing the event to William Stukeley, author of Memoirs of Newton’s Life (1752):

After dinner, the weather being warm, we went into the garden and drank thea [sic], 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?

So the apple tree really did inspire Newton, even if the apple didn’t fall on his head. The account is online on the Royal Society’s website if you want to see it.

Just as Newton had never before considered why it was that apples fall to the ground, even though I had heard the story many times before I’d never wondered which actual apple tree had inspired him. That was, until I saw several pieces of it behind the scenes at the Royal Society.

Newton’s fabled apple tree once stood in the garden of his childhood home, Woolsthorpe Manor in Lincolnshire. In 1800, the inspirational tree blew over. Luckily, it re-rooted itself, and a new tree, an offshoot from the original, is still flourishing there today.

The owner of Woolsthorpe Manor saved some pieces of Newton’s original apple tree after it blew over. Some of them are in the Royal Society archives. On a shelf down in the cool basement are two fragments, as well as two rulers and a prism made from the wood. One of the fragments is in a little pink plastic bag, because it has just been on an adventure, up into orbit aboard the Space Shuttle Atlantis in 2010. It will remain in the pink bag, because the bag is now part of its history.

The apple wood was taken up into orbit so that it could experience zero gravity. The plan was also to drop a real apple on the space station and film whether it was subject to gravity or not. They weren’t able to do the test because an astronaut who didn’t know what they were up to – she will remain nameless – saw the apple lying around and ate it. They could hardly pop out to the shops, so they had to make do with a pear. You can watch a film of it floating.

Keith told me the pear is flying, not because it wasn’t subject to gravity, but because the space station is falling, and the pear with it, in orbit. ‘Just look at the astronauts’ hair,’ he said. It floats above their heads.

Also in the archives is a lock of Newton’s hair – perhaps with high concentrations of mercury in it, as a result of his alchemical experiments – and his death mask. ‘This is the closest you’ll get to Isaac Newton,’ said Keith.

We looked at a drawing of Newton’s apple tree, sketched by Thomas Howison in the 1820s. It is of the original tree, which lies dead on the ground, and the re-rooted tree beside it. Keith had just been having a good look at it and discovered a new secret. We peered at it (have a look yourself) and could just make out the outline of Newton sitting underneath the tree. Keith had seen the picture countless times but had only just noticed the faintly drawn figure beneath it. ‘The archives are still turning up secrets,’ he said.

On a shelf beside the pieces of apple tree sits Newton’s reflecting telescope (he donated it to the Royal Society; they lost it for a while but it turned up again in the 1730s in an instrument maker’s workshop). It has two mirrors inside, and two tubes, which you slide to focus the mirrors.

Before Newton had the brainwave of using mirrors, looking at the stars meant holding two enormous and unwieldy lenses far apart, tied together by pieces of string. Newton mounted his old, big telescope on a maypole, which he’d bought on Charing Cross Road.

He invented this small, wood and leather reflecting telescope while he lived in Cambridge. Later, he came to London and worked from a laboratory at the Tower of London, where he was Master of the Royal Mint. Imagine him peering up into space from his rooms inside the Tower.

When he made his telescope he sent his idea to the Royal Society and included a drawing. I loved looking at Newton’s sketch, complete with an eye looking down into the telescope. Then I was able to put my own eye to his telescope, just as he would have done. All I could see was the wall of the basement, but I got the idea. Amazingly, centuries later, the Hubble space telescope was built using essentially the same design.

The Royal Society owns many of the letters Newton sent over the years, explaining what he was up to. Some were expanded upon and turned into publications. The original manuscripts of these texts are here in the archive.

We looked at the original copy of the Principia (Philosophiae Naturalis Principia Mathematica) that Newton sent away to be published. This first copy was written up by his secretary and has marginalia in Newton’s hand and in the writing of his friend Edmund Halley – of Halley’s Comet fame who paid for it to be published.

The Royal Society was planning to cover the costs, but the publication of A History of Fishes, by Francis Willughby and John Ray, had left them out of pocket. Samuel Pepys was the Society’s president at the time and is named on the title pages of both the Principia and A History of Fishes (his diary wasn’t published until 123 years after he died).

Willughby had been Ray’s student and the two travelled together studying and collecting birds and fish. When Willughby suddenly died, Ray saw his three books – about birds, fish and games – through the press. The twosome’s collection of birds and fish is stored at Willughby’s family home, Wollaton Hall, which, incidentally, starred as Wayne Manor in the Batman film The Dark Knight Rises.

Back in 2010, Keith had the pleasure of showing Newton’s Principia to some Apollo astronauts – Gene Cernan, Neil Armstrong and Jim Lovell – when they visited the Royal Society. He really enjoyed their visit. ‘I am a child of the sixties; that is why I got into all of this,’ he told me.

As they turned the pages of the tome, Gene Cernan talked about how he had experienced Newton’s third law of motion – that every action has an equal and opposite reaction – first hand, in space. When he flew on Gemini 9, he had to assemble a backpack in zero gravity, with little light, outside the spacecraft. Nothing was holding him anywhere, so as he tightened a valve, his entire body span in the opposite direction. Everything he touched would touch him back and send him tumbling back out into space. When he touched the spacecraft, it repelled him. He had trouble getting back inside and when he finally made it his boots were filled with sweat.

From then on, NASA put hand and footholds on its space capsules so that the astronauts could anchor themselves in space. The astronauts were also trained in water so they could experience weightlessness. By the time Cernan flew to the moon with Harrison Schmitt, on Apollo 17, he knew how to get around without gravity.

When the Royal Society lent their fragment of Newton’s apple tree to NASA astronaut Piers Sellers to take up to the space station, they also sent along a picture of Sir Isaac Newton. The crew put it in the window of the space station so that Newton could look out: they thought he would have liked the view. Imagine what Newton might have come up with, if he’d had the chance to spend time up there with them, quietly looking around at the universe getting on with what it does, and figuring out how things work.

[Sir Isaac Newton (1643–1727)] Isaac Newton was born in Woolsthorpe, Lincolnshire. In the garden grew a Flower of Kent apple tree connected with the tale of Newton’s discovery of the law of gravitation – a story which Newton himself started.

[Newton’s Apple Tree by Thomas Howison] If you look really closely you can see a ghostly figure of Sir Isaac Newton sitting on a branch of the fallen tree.

[Newton’s reflecting telescope] Newton sent a sketch of his Invention to the Royal Society. I saw it in their library. He included a sketch of his eye, looking down into the telescope. I was able to put my own eye to the telescope, just as he would have done centuries ago.

[Newton’s Principia] The Royal Society has the original proof copy of Newton’s masterpiece Philosophiae Naturalis Principia Mathematica, down in the basement.

[Two pieces of Newton’s apple tree] A piece of the apple tree that inspired Newton was taken onto the space station, along with a photograph of Newton, below.

Imagine what Newton might have come up with, if he’d had the chance to spend time aboard the space station.

‘YOU COULD SAY THIS ENTIRE room is a hidden treasure,’ said the curator of the Linnean Society as the door swung open to their basement storage facility. She flicked the lights on to reveal a wood-panelled room lined with 1,600 books and drawers filled with 14,000 plants, 3,198 insects and 1,564 shells, which were the private collection of Carl Linnaeus, the man who named the natural world.

Carl von Linné (1707–78), who was born Carl Linnaeus, was a Swedish botanist. He standardized the system of scientifically naming plants with two Latin names, the genus (e.g. Ginkgo), followed by the species (e.g. biloba). This is called binomial nomenclature, and it is now used internationally for all plants and animals, even us humans. We are in the genus Homo and our species is sapiens, hence Homo sapiens, ‘the wise man’. Linnaeus came up with our name.

It’s a really clever system if you think about it, because anyone around the world can understand what plant or creature you are talking about. It’s essential for botanists, zoologists and museum curators caring for collections of specimens.

When a new species is discovered, scientists must explain to other scientists what it is and what it looks like. So the first thing they do is pick one member of the species as a holotype, or ‘type’, specimen. This is the example of the new species that will forever define it and is often the first example of the species found. Most of these ‘types’ are in museums around the world; thousands of them are in this room because Linnaeus gave them their scientific names.

There is not, as yet, a type for Homo sapiens. A palaeontologist named Edward Drinker Cope (1840–97) asked for the job in his will, but he turned out to have syphilis, so was struck off the list. Arnold Schwarzenegger has been proposed. Many say it ought to be Linnaeus, as he came up with the idea. His body is well preserved in the cathedral in Uppsala, Sweden, so there is a chance of this happening yet.

The specimens housed at the Linnean Society used to be in Uppsala, in Linnaeus’s home, where he lived with his family. When Linnaeus died, Joseph Banks (1747–1820) – the director of Kew Gardens and a passionate botanist – tried to buy the collection, but in the end a young student of his, James Edward Smith, bought it with money he borrowed from his father, and shipped the whole lot to London, where he founded the Linnean Society.

This is the cave of riches that I went to see. It is just inside the entrance to the Royal Academy of Arts. I met the librarian, Lynda Brooks, in the library, and we ventured downstairs to the basement, where the collection lives. She turned a key that opened a door into Linnaeus’s world.

The entire room smells like a lovely combination of old books and wood polish. The top shelves are filled with books Linnaeus wrote himself, and his reference books. The lower drawers and shelves are filled with thousands of insect, shell and plant specimens collected by him and by his ‘apostles’ – his students, who collected around the world for him. These men of science would also act as pastors, priests or doctors whilst on collecting expeditions.

We began with the plants. Linnaeus pressed each one carefully, described it and gave it a scientific name, and then stored it away. Later, these were parcelled up, so each plant is now a brown paper package tied up with green string, each one stacked upon another. We unwrapped one package and, inside, we found the type specimen for Delphinium. Two hundred and fifty years after Linnaeus named it Delphinium (after the Latin for ‘dolphin’, because of the shape its flower makes as it opens, like a dolphin leaping out of the waves), it is still a vivid blue colour because it has been kept in storage, out of the light. This is just one in his library of thousands of plants.

We also unwrapped what was for Linnaeus a very special flower, Linnaea borealis, which was named after him and became his signature flower. If ever you see a painting of him, look for the flower. He usually has it draped through his fingers. When alive, it is pink, and its delicate petals carpet the floor of woodland in Sweden. At night, the pink burns in the darkness. The type specimen in the archive has turned brown over the centuries, unlike the delphinium. Pink and red flowers lose their vibrancy more quickly than blue and yellow ones.

Scientific names aren’t just for scientists. They tell stories. Buttercups are in the Ranunculus genus. They often grow near water and ranunculus is the Late Latin word for ‘little frog’, a species also found near the water. Water lilies are in the genus Nymphaea, after the water nymphs in Greek myths. The laurel Kalmia was named by Linnaeus for his Swedish student Pehr Kalm; the black mangrove Avicennia he named for the Persian physician Avicenna. He also reused classical names: Acer (maples), Quercus (oaks). The only plant Linnaeus named after a female body part is a blue vine popularly called a ‘butterfly pea’; he gave it the genus Clitoria. If you look up your favourite plant, it is bound to have a good story hiding in its scientific name.

The same goes for animals. Some animals Linnaeus named descriptively, like the southern flying squirrel, Glaucomys volans (‘the white mouse that flies’); in others, he added things that made him smile. He named the blue whale – the largest animal that has ever lived on earth – Balaenoptera musculus. In Latin, musculus means ‘little mouse’. He named the house mouse at the same time: Mus musculus. There are no mammals in the basement room of the Linnean Society – though some do still survive in Sweden – but there are a lot of fish pressed on to paper, their skin flattened as if they were flowers, as well as corals, shells and insects.

There is also, in among them, a little box that contains pearls made by Linnaeus. They are the first artificial pearls ever cultured in a mollusc. He made the pearls by jamming a piece of limestone into a freshwater mussel, Unio pictorum (the ‘painter’s mussel’, so called because artists would use the shallow valves to mix their pigment), and holding it there so the mussel would create a pearl around it. Then he put the mussel back into the river for six years, giving the pearl time to grow.

The pearls are small and roundish, apart from one elongated brown one that looks like it went a bit wrong. One has been cut in half, so I could see the irritant he put inside it to make the mussel form the pearl. It looks like a seed in the middle of the pearl.

Linnaeus sold his secret in 1762 to a Swedish merchant called Peter Bagge who got a permit from the king to make pearls, but even though he paid 6,000 dalars (more than £93,000 today) for a monopoly on the right to make pearls, he never got around to making any. Linnaeus once said that he wished he’d become famous for creating these pearls rather than for classifying nature. After taking a good look, we put them back in their box, in their drawer, and closed it shut.

Next, we took down some books. The first was a green leatherbound book with ‘LINNAEUS’ embossed in gold letters on the front. It was his journal from a trip he made to Lapland. It is filled with his notes, in his slanting handwriting, on the people, flowers and creatures of Lapland, and wonderful – if not that competent – drawings of local life.

We turned the pages and saw his charming sketches of ploughs, fish, skis, insects, coral, local Laplanders, embroidery on Sami clothing and tents. There were drawings of how the Lapps slept, ate, dried fish and even the kinds of games they played (throwing balls and a game that looks like chess). There is a beautiful sketch of a crane fly, and an interesting one of Andromeda being threatened by a sea monster beside one of an Andromeda plant being threatened by a newt. I really liked his drawing of an owlet and one of a Sami baby wrapped up cosily.

He tells how to cure chilblains with roasted reindeer cheese, how to fix a broken pot by boiling it in milk and how to make thread from reindeer hooves. He described the singing in Lapland: ‘No Laplander can sing, but instead of singing utters a noise resembling the barking of dogs.’

The journal was published as Iter Laponicum but it was brilliant to see the real thing, written in Lapland. Linnaeus brought it back to his home in Uppsala, along with a drum and a Lapp costume. There is a painting of him wearing it holding the drum and his Linnaea borealis plant, in the library upstairs at the Linnean Society.

I’d been told that Linnaeus was the first person to grow a banana in Europe, so I asked Lynda whether there was anything banana related in the collection. She opened up a book called Musa Cliffortiana Florens Hartecampi, all about that first banana. It was grown in the garden of Linnaeus’s friend George Clifford, in Holland. Musa is the genus for banana; it was named from musz, which is the Arabic word for ‘banana’; or perhaps for the nine Greek muses themselves. Inside the book is a fold-out drawing of the fruiting banana plant. It ends with a question: ‘Will my banana grow for years?’

Lynda then showed me Linnaeus’s most famous work, Systema Naturae. Published in 1735, it’s a history of all the living things he knew about at the time, divided up according to his sexual system for classifying them. He caused a bit of a scandal at the time by suggesting plants had a sex life. There are so many names he adopted which we still use today; magnolia, clematis, digitalis, jasmine, fuchsia, salvia.

Animals are included in the Systema, written down in a table, according to the genus Linnaeus assigned to them. If there was an animal he wasn’t sure about, he put it in ‘Worms’. He put humans in the same box as apes, which he didn’t want to do, but he couldn’t see a way around it. Anything he wasn’t sure actually existed he put in a box called ‘Paradoxa’, which contains the satyr, phoenix, dragon, unicorn and pelican. He wasn’t sure he believed in pelicans, because they were supposed to feed their young on their own blood. He also named stones, fossils and minerals. This first edition copy was huge, the only one that was published in such a big format. Linnaeus used to fold it into four and carry it around with him.