Author Archives: Alison Boyle

About Alison Boyle

Deputy Keeper of Science and Medicine | @ali_boyle

Busy bees

Recently, searching the physics collections on our object database, I was intrigued by an entry for a ‘radiation detector built to detect bees marked with radium’. Some research from our wonderful volunteer Eduard revealed more.

A discharge (gas) tube from Gilbert Tomes's bee detector (Science Museum).

The device was designed by Gilbert Tomes in the early 1940s. Tomes, a keen amateur apiarist, was seeking a way to track swarms by detecting when the queen bee left the hive. He tried tagging the queen with a tiny magnet to trigger a circuit as she left  – but as you might imagine, attaching magnets to bees was a tricky job.

Dabbing them with luminous paint proved somewhat easier, but Tomes’s photocell detector setup was triggered by other light sources as well as the painted bees. Then he remembered that the luminous paint contained radium (despite increasing awareness of its dangers from the early 20th century, radium paint was widely used in WW2-era instruments).

As part of their work for the Baird Television company, Tomes and his colleague Alec Tidmarsh had been investigating Geiger-Muller tubes, which at the time were little used outside scientific circles. They made a simple device to detect the radioactive bees, which they showed to London Zoo‘s head beekeeper. Impressed, he sent a story to the Press Association, and suddenly the ‘Tomes Queen Detector’ was big news.

Tomes and Tidmarsh were deluged with requests for their Geiger counters and a few years later founded 20th Century Electronics (now Centronic), which became a global leader in detector technology.

Woodcut of bees in a herbal encyclopedia, 1497 (Science Museum).

Perhaps the company’s success improved Tomes’s wife’s opinion of his bee research. In his diaries on 19 September 1941, Gilbert noted: ‘Feeding bees with sugar syrup.  This was rather a sticky business and Mary did not like her kitchen being taken over.  She wanted to know why we had to feed the bees when they were supposed to be feeding us with honey’.

Catching the Sun

So, did any of you make it to Easter Island to see last weekend’s total solar eclipse? The path of totality crossed very few landmasses, so observing this eclipse was for the most intrepid travellers. Next weekend marks the 150th anniversary of a solar eclipse which was somewhat less remote – but observed by some very intrepid travellers, who for the first time used photography to settle a scientific debate. 

On 18 July 1860, Warren De la Rue and his team eagerly awaited the eclipse in their makeshift wooden observatory at Rivabellosa in northern Spain. The observatory and its contents – some two tons of apparatus – had been transported from Plymouth to Bilbao on board HMS Himalaya and then by stagecoach to Rivabellosa, where De la Rue persuaded a local farmer to set aside his threshing floor for the observatory.

De la Rue's eclipse observatory as shown in the Illustrated London News, 1860 (Science Museum).

The key piece of apparatus was the Kew Photoheliograph, designed by De la Rue a few years before. The first instrument specifically designed to photograph celestial objects, it was regularly used at Kew Observatory to record images of the Sun and Moon. The astronomers hoped that its wet collodion plates, with their short exposure times, could record the prominences visible during a solar eclipse. At the time it was not known whether these were part of the Sun, or an effect of the Earth’s atmosphere.

The Kew Photoheliograph is on display in Cosmos & Culture (Science Museum).

Working in the hot Spanish summer, the astronomers only had a few minutes to develop each plate before the wet collodion dried. But they successfully recorded prominences on several plates – De la Rue described them with names including Cauliflower and Boomerang. When the photographs were compared with ones taken by Fr Angelo Secchi 500km away at Desierto de las Palmas, the two sets were so similar that they proved prominences are intrinsic to the Sun.

An expedition photograph of the eclipse before totality (Science Museum).

For a lively account of the Rivabellosa expedition – including the tale of how the observatory almost burned down just minutes before the eclipse(!) - check out Stuart Clark‘s The Sun Kings.

From Planck to pigeon poo

The European Space Agency has just released the first all-sky map from the Planck satellite. The centre of the map is dominated by purple swirls from the dust around our Galaxy, but Planck’s main business is to look closely at the blobby structures visible in the map’s outer regions. These ’blobs’ show temperature fluctuations in the Cosmic Microwave Background (CMB), the remnant radiation from the Big Bang. Irregularities in the CMB became the seeds of today’s galaxies.

Planck's all sky survey (ESA, HFI and LFI consortia)

The fluctuations in the background radiation were first mapped by NASA’s COBE satellite, launched in 1989. An instrument on board also measured the CMB’s spectrum. FIRAS’s moving mirrors created interference patterns in a radiation beam, enabling the precise spectrum to be reconstructed. To the delight of scientists, the results perfectly matched the predictions of Big Bang theory.

This prototype mirror mechanism for the FIRAS instrument is on display in Cosmos & Culture (Science Museum).

The FIRAS prototype is on loan to us from the kind folks at the Smithsonian Institution’s National Air and Space Museum in Washington DC.  NASM’s display about the 1964 discovery of the microwave background features one of my favourite objects in any museum, anywhere. Arno Penzias and Robert Wilson initially thought that an annoying background hiss from their radio antenna was caused by pigeon droppings, and used this trap to try and capture the pesky critters. It turned out they’d accidentally found what other scientists had been looking for – the Big Bang’s echo.

A quacking tale

Recently, my colleague David mentioned that we’re planning a major history of science gallery as part of our master plan. It’s got us thinking about some of our favourite objects in the collections. Here’s one of my all-time tops:

'The First Years' plastic duck, c.1992

Yes, it’s a toy duck. But not just any old toy duck. It’s part of a consignment of plastic toys lost from a container ship in the North Pacific during high storms on January 10, 1992. Around 29,000 toys spilled from the container and have been making a swim for it ever since, to the shores of Alaska, surviving ice in the Bering Straits, and heading into the North Atlantic.

Oceanographers Curtis Ebbesmeyer and James Ingraham have enlisted the help of beachcombers worldwide to track where the toys wash up. By following the mighty ducks and their floating friends, they can refine their models of ocean surface currents. It’s a great illustration of how scientists can come up with imaginative solutions to problems, and a charming example of members of the public working in tandem with scientists. Oceanographers track all sorts of flotsam – there’s also a flotilla of trainers bobbing about out there - but the storytelling potential of rubber duckies floating around the world’s biggest bathtub makes this case particularly appealing. You can find out more about Curtis and the ducks in his book.

The yellow ducks were accompanied by blue turtles, green frogs and red beavers who've since faded to white (Science Museum).

These toys are part of the first wave to be washed ashore – large numbers landed in Sitka, Alaska, ten months after the spill. We acquired these toys in 2005, following a response to posts we put on Sitka community websites under the heading ’Science Museum, London, looking for a duck!’  We decided they should travel to the Museum in a box, by air, rather than swimming for it…

Over the rainbow

Recently, I was lucky enough to visit the mighty Victoria Falls. As I stood at the falls’ edge drenched in spray, I spotted double rainbows formed by sunlight being refracted through the water droplets.

A rainbow, with a fainter secondary companion above, at Victoria Falls. (Alison Boyle)

One of the first people to explain how rainbows form was the Persian mathematician Kamal al-Din al-Farisi, who was born around 1260. Using a glass sphere filled with water to represent a raindrop, he showed that sunlight is bent as it enters the drop, reflects off the back of the drop, and is bent again on its way out. If rays are reflected twice inside the drop, a secondary rainbow is formed with the colours reversed. Here’s a more detailed explanation. Around the same time Theorodic of Freiberg performed a similar experiment. The two were not in contact, but both had been influenced by Ibn al-Haytham‘s Book of Optics. You can find out more about al-Farisi and al-Haytham in the 1001 Inventions exhibition.

Rainbows have fascinated people for centuries, as this illustration from 1535 shows. (Science Museum)

Isaac Newton explained that the rainbow’s colours arise as a result of white light being split into its constituent colours. Many people will have childhood memories of making a Newton colour wheel with a disc of cardboard and a pencil. Here’s a late 19th century version.

A 19th century demonstration apparatus. (Science Museum)

As our understanding of the nature of light has continued to change, so has our understanding of the rainbow. For a detailed account of how people have portrayed rainbows in science and beyond, check out Raymond Lee and Alastair Fraser’s The Rainbow Bridge: Rainbows in Art, Myth and Science.

Light fantastic

Fifty years ago yesterday, Theodore Maiman demonstrated the first working laser. At the time, there didn’t seem an obvious use for the technology (although several newspapers ran fanciful stories about ‘death rays’) and it was dubbed ‘a solution looking for a problem‘. Five decades on, lasers are so widespread that we barely notice our everyday encounters with them at the office printer, the supermarket barcode scanner, or the DVD player at home.

DVDs are written and read by laser. (Science Museum)

The basic principle of a laser is pumping energy into a medium to excite its atoms so that they emit photons of light, then amplifying and aligning this emission. The first lasers used ruby rods as the medium – here‘s an explanation of how a ruby laser works.

The chamber of this early laser is opened so that you can see the ruby rod. (Science Museum)

Since then a huge variety of materials has been used in lasers including gold, organic dyes, semiconductors, and gases like helium-neon (the common red laser) and carbon dioxide, widely used for industrial cutting and welding. Or, more weirdly, lasers have even been made from jelly!

The world's first Transversely Excited Atmospheric laser, built at Baldock in 1974, uses a cylinder of carbon dioxide as the medium. (Science Museum)

As well as the now-familiar everyday uses, lasers are increasingly used in medicine. Laser guide stars have helped sharpen the view of major telescopes. Laser weaponry is moving out of the world of James Bond and into reality. One day, lasers might even be used for fusion, providing us with plentiful clean energy. For a more detailed take on the laser’s fascinating history and promising future, check out the special anniversary edition of Physics World. Here’s to the next fifty years.

Shrouded in mystery

The Shroud of Turin is on public display for the first time in a decade. The Pope paid a visit  on Sunday and over two million people are expected to queue up to see the shroud during a six-week showing in Turin Cathedral. Some people will be there because they believe the shroud is the burial cloth of Christ, others will be sceptics wanting a closer look at what has widely been dismissed as a medieval forgery.

This small container carried a small sample of the shroud to Oxford for testing. (Science Museum)

A strong case against the shroud’s authenticity was made in 1998, when samples were radiocarbon-dated by three independent laboratories. This container in our nuclear physics collection was used to transport the sample that went to the University of Oxford’s Radiocarbon Accelerator Unit - the red wax is the Archbishop of Turin’s seal confirming that the sample came from the shroud. The Oxford experiments concluded that the sample was around 750 years old, in broad agreement with the results from the other laboratories.

Seemingly conclusive evidence that the shroud is from the Middle Ages and not the time of Christ. But some people have argued that there may be other explanations, for example the shroud being contaminated during centuries of storage, or the samples having been taken from a medieval repair patch on a much older artefact.

Further testing may help to pin down the age of the fabric, although so far the Catholic Church has been reluctant to expose this iconic artefact to further study. And an agreed age still wouldn’t explain how the image of the man was formed – and certainly not who that man was. During his visit the Pope was careful to remain non-committal on the question of the shroud’s authenticity. It looks like this controversial item will remain a scientific as well as a religious mystery for a while longer.

Celebrating James Ferguson

Walk into any museum curator’s office and you’ll encounter a mass of books and papers. It’s not that we’re messy – well okay, I am – but a lot of the material we use can’t always be found on the web. Even on Stories from the Stores.

One of my favourite books on my shelves is Astronomy Explained upon Sir Isaac Newton’s Principles by James Ferguson, who was born 300 years ago last Sunday. Published in 1785 (the first edition was 1756), it’s intended ‘for those who have not studied mathematics’ and contains beautifully illustrated explanations of how the Solar System works.

Ferguson in his study. (Science Museum)

Ferguson travelled around England giving lectures on natural philosophy. These were hugely popular, aided by the ingenious models he built to demonstrate scientific phenomena.

Ferguson's wooden orrery (c. 1755) uses hand-driven pulleys to demonstrate the motion of the Earth, Sun and Moon. (Science Museum)

Before moving to England and making his name as a lecturer, Ferguson lived in Edinburgh where he made a living as a miniature portrait painter. These pencil-and-ink miniatures show his talent:

Portrait miniatures made by Ferguson in the 18th century. (Science Museum)

And although you can’t find everything on the web that you can in a curator’s office, you can find out more about Ferguson for yourself by reading his autobiography here, and enjoy Astronomy Explained here.

For she’s a jolly good Fellow

On Tuesday I attended our annual ‘Fellows of the Science Museum’ reception, in which we recognise the contributions of leading scientists and educators. This year we were particularly celebrating female scientists, with a speech from new Fellow Jocelyn Bell Burnell

Jocelyn in 1968. (Science Museum)

In 1967, Jocelyn was a PhD student at the Mullard Radio Astronomy Observatory in Cambridge. Her job was to analyse data from one of the telescopes for the characteristic twinkling of quasars. One day she noticed a ‘bit of scruff’ on the telescope’s charts and, rather than dismiss it as interference, decided to investigate further. It turned out to be a pulsed signal, always coming from the same patch of sky and repeating at regular intervals. For a short time, the Cambridge team had to consider the possibility that it was a signal from an alien civilisation – they jokingly dubbed it LGM-1, for Little Green Men.

The signal from the first pulsar appeared on the cover of Joy Division's 'Unknown Pleasures' LP. (Science Museum)

Jocelyn and her supervisor Antony Hewish (who’s also a Science Museum Fellow) soon detected signals from other parts of the sky and realised they had found a new class of cosmic object – a rapidly-spinning dense star. They are called pulsars and over 1800 are now known. 

Part of Jocelyn’s telescope is on display in Cosmos & Culture. It might take you a while to spot it, as it doesn’t look anything like your average telescope:

The pulsar array is now retired. During use, sheep kept the 4 acres of grass neatly trimmed. (Alison Boyle)

Jocelyn was recently the subject of the BBC’s Beautiful Minds.  Beauty is the theme of next Wednesday’s Science Museum Lates, and Jocelyn will be there talking about her work and inspirations. Hope to see you there!

Sweet Caroline

Great to see Caroline Herschel making the Royal Society‘s list of influential female scientists. Although she’s often been overshadowed by her brother William, her own contribution to astronomy was immense.

In 1772, Caroline escaped a life of domestic servitude in Hanover to join her brother in Bath. William had forged a successful musical career and needed someone to keep house. Caroline, with her fine soprano voice, joined him in many performances.

Caroline sang at this performance of Handel's Messiah conducted by William. (Science Museum)

However, she soon discovered that what William really wanted was someone to indulge his passion for astronomy. ‘Almost every room turned into a workshop’, she noted, as their house bore the marks of William’s telescope-building.

William’s perfectionism paid off with the discovery of Uranus in 1781, and he was appointed King’s Astronomer to George III. Caroline received a salary as his assistant, making her the first professional female astronomer.

This 1800 letter from George III awards Caroline an annual salary of £50. It's on display in Cosmos & Culture. (Science Museum)

The Herschels moved to Slough, near the King at Windsor. Caroline had mixed feelings about this, as it meant giving up her musical career. But she threw herself into astronomical work. As well as assisting William, she discovered several comets and compiled catalogues of stars and nebulae.

Caroline discovered eight comets with her 'comet sweeper' telescope. (Science Museum)

Caroline also left an important legacy for historians of science. Her memoirs give an insight into the work of the Herschels and their counterparts, and also tell a lively human story. She describes having to force morsels of food into William’s mouth while he obsessively polished telescope mirrors for hours on end, and recounts a painful incident where she became impaled on the 40ft telescope.

William built this 7ft telescope for his sister. It's on display in Making the Modern World. (Science Museum)

If you want to find out more about Caroline I heartily recommend The Age of Wonder by Richard Holmes, or her own words in the autobiographies, edited by Michael Hoskin. Or you could visit the Herschels’ house in Bath, now a wonderful museum.