Category Archives: Chemistry

Women of substance

Continuing our Women’s History Month theme, today we’re celebrating International Women’s Day. As the theme for 2011 is ‘equal access to education, training and science and technology’, it seems like a good day to celebrate Kathleen Lonsdale, who in 1945 became the first woman to be elected a Fellow of the Royal Society, along with microbiologist Marjory Stephenson (only 285 years after the men).

Kathleen Lonsdale in 1957 (Science Museum).

Lonsdale was a pioneer in the field of X-ray crystallography, in which scientists fire X-rays at crystals and study how they are scattered. This enables them to infer how atoms are arranged inside the crystal.

Lonsdale's models of the structure of ice, 1955 (Science Museum)

In the early days, it was an arduous process. Capturing X-rays on film could result in burns to the fingers. Calculating the atomic layout from the X-ray patterns had to be done manually, involving hours of slogging. Things got somewhat easier with the advent of scientific computing. The Pegasus computer on display in our Computing gallery (the world’s oldest working electronic computer) was used by Lonsdale’s group at University College London.

Pegasus speeded up crystallographers' calculations (Science Museum).

Lonsdale faced the additional challenge of being a woman in a man’s world, and for a time struggled to combine scientific work with raising a family. Her mentor William Henry Bragg arranged for a grant to help support her at home so that she could carry out her world-class research. Lonsdale said that to succeed as a woman scientist one must be a first-class organiser, work twice the usual hours, and learn to concentrate in any available moment of time.

In the early-to-mid 20th century, the field of X-ray crystallography was unusual in having a number of high-profile women scientists, including Lonsdale, Helen Megaw, Rosalind Franklin, whose X-ray photograph of DNA was infamously used by Crick and Watson in determining the double helix structure, and Nobel prizewinner Dorothy Hodgkin. Hodgkin always resisted being singled out as a ‘woman scientist’, but cannot have been impressed with the Daily Mail’s headline announcing her award: ‘Oxford housewife wins Nobel Prize’.

Dorothy Hodgkin in the 1940s (NMeM / Daily Herald Archive / Science & Society)

Things are easier for women in the sciences today but a 2010 report suggests that, in the UK at least, the picture’s still not so rosy – despite an increase in females studying science, technology and medicine, women still only make up 12% of the workforce. And women are noticeably absent as the famous faces of science. There’s still some way to go before the likes of Lonsdale become the norm rather than the inspirational exceptions.

Women in History month

March is National Women’s History Month. To coincide with the centenary of the Nobel Prizes, it seems an ideal time to look at the achievements of Marie Curie (1897-1934).

Marie and Pierre Curie with their daughter, Iréne (© Science Museum / Science & Society )

Marie Curie was the first scientist to win two Nobel Prizes - one in 1903 with her husband Pierre and the another in 1911 for Chemistry for her work on radioactivity.

Glass flask used by Marie Curie ( © Science Museum / Science & Society )

Like many of the objects Marie Curie used in her work, this flask has slight traces of radioactivity and needs to be stored and handled carefully.

Certificate signed by Marie Curie, 1926 ( © Science Museum / Science & Society )

This certificate specifies radium content signed by Marie Curie in her role as director of the Institute de Radium. Radium became used for cancer treatments and you can read about the ‘radium bomb’ courtesy of my colleague Katie.

Marie Curie also provided radioactive samples to other researchers including Sir William Crookes. Crookes invented a device for visualising radium and its decay – a spinthariscope using the radium Marie Curie provided.

Crookes' experimental spinthariscopes, c. 1902 (© Science Museum / Science & Society )

And it didn’t end there. Marie Curie’s daughter Iréne Joliot-Curie (1897-1956) followed in her mother’s footsteps. Iréne worked with her husband Frédéric Joliot (1900-1958) on producing artificial radioactivity.

Glass tube used in the discovery of artificial radioactivity (© Science Museum / Science & Society )

The second generation husband and wife team won a Nobel Prize for Chemistry in 1935 for their discovery.

What was Watt up to in the vegetable patch?

How many uses can you think of for red cabbage? Not as many as James Watt I’ll bet…

His friend William Nicholson wrote a Dictionary of Chemistry in 1795. The entry for red cabbage reads:

BRASSICA RUBRA – Mr Watt finds that red cabbage affords a very excellent test, both for acids and alkalis; in which it is superior to litmus, being naturally blue, turning green with alkalis, and red with acids.

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Red cabbage used in chemistry [Science Museum / Science & Society

The description of how he prepared the cabbage leaves includes boiling them for several hours. No wonder Mrs Watt banished his workshop activities to the top of the house.

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Mrs Annie Watt, James's second wife [Science Museum / Science & Society

Watt’s home at Heathfield near Birmingham was surrounded by gardens and parkland, so there was plenty of space for him to try out his ideas without disturbing the neighbours.

He made the most of the flower gardens, as Nicholson also remarks that he then checked out violets, scarlet roses and pink coloured lychnis for similar reasons.

He wasn’t the only one. Robert Boyle had investigated the use of similar colour changes for acid-alkali reactions in the 17th century. Watt’s chemical interests were both philosophical, and intensely practical – he tried a number of ways of turning science into money, including bleaching, dyeing, and making ink.

Christmas Science Spectaculars

Hope everyone enjoyed the holidays. If you got a bit bored of watching re-runs of the soaps while chewing on leftover turkey, you could have entertained yourself by tuning in to the Royal Institution’s Christmas Lectures.

This year, materials scientist Mark Miodownik talked about everything from chocolate to elephants and you can still catch the lectures on  BBC i-Player.

The RI’s Christmas Lectures began in 1825 and have continued ever since, pausing only during World War II. The roll of past lecturers includes such famous names as David Attenborough and Carl Sagan. But the person who’ll always be most associated with the Christmas Lectures is their founder Michael Faraday, with 19 of the annual series to his name.

Faraday first gave the festive lectures himself in 1827-8. His series of family lectures on chemistry wowed audiences and the press. By 1855, when this lithograph was made, lecture-goers included such distinguished guests as Prince Albert.

Faraday's lecture of 27 December 1855 (Science Museum)

The Royal Polytechnic Institution, famous for ‘abominable smells and… the odd explosion’, also started running a popular series of Christmas lectures. Such shows became a festive feature at institutions around the country.

An Illustrated London News engraving of 'Christmas at the Polytechnic', 1858 (Science Museum)

The RI lectures aren’t the only festive legacy of the 19th century – the aforementioned Prince Albert is often credited with introducing the Christmas tree to Britain. Actually, some people (including the royal family) had adopted the German tradition years before, but it was Albert and the popular Queen Victoria who made it widely fashionable. I guess it’s about time to get round to vacuuming up those pine needles…

Enjoying the Christmas tree, c.1948 (NMeM / Photographic Advertising / Science & Society)

Fantastic fireworks

It’s that time of year when leaves cover the ground, there’s a chill in the air, and household pets look distinctly nervous.

Hallowe’en has just passed and this weekend will see fireworks displays throughout Britain as the bonfires are lit for Guy Fawkes Night. But even the most spectacular pyrotechnics would be hard-pressed to beat these 17th-century creations.

Fiery dancers and a dragon, 1635 (Science Museum)

This engraving is from the Science Museum Library‘s copy of Pyrotechnia or, A discourse of artificial fire-works, written by John Babington and published in 1635.  A musical device ‘with anticks dancing’ is followed by a dragon spewing flame from its eyes, mouth, and … ahem … anus.

Pyrotechnia's water-borne fireworks (Science Museum)

There were also firework devices designed to float on water – this illustration shows a sailing ship, a mermaid, and another dragon about to do battle with a trident-waving Neptune. We’ve digitized more pages from Pyrotechnia on our Ingenious website.

It wasn’t all fun and games – Babington, a gunner, was also aware of the applications of gunpowder in warfare, and experimentation with devices such as these was a good way to try out about different powder ingredients. You can find out more in this book by Simon Werrett.

In the meantime, have fun at the fireworks if you’re off to a bonfire this weekend – hope you enjoy them as much as this young man!

Blowing the pocket money on fireworks, 1949 (NMeM / Daily Herald Archive / Science & Society)

Batteries not included

What’s the one gadget you couldn’t live without? Your mobile phone, PDA, music player, game console – or all those things combined in a sleek smartphone?

No matter which device you choose, the one thing that all these gadgets couldn’t exist without is their rechargeable battery - the beating heart of the modern world.

The first rechargeable battery was the Lead-Acid battery, invented in 1859 by Gaston Planté, but it was the Nickel Cadmium battery invented in 1899 by Waldemar Jungar that really paved the way for the future of mobile technology.

The very early mobile phones used Nickel Cadmium batteries, but the batteries were so enormous they had to be stored in the boot of a car. As demand increased improvements were made and soon you were able to carry your battery around with you in a handy carry case.

Vodafone transportable mobile phone, 1985. (Science Museum / Science & Society)

By 1983 the first stand alone mobile phone had been developed using the Nickel Cadmium battery the Motorola Dynamic Adaptive Total Area Coverage (DynaTAC 8000X). By 1989 they could even fit in your pocket – though it might have to be quite a large pocket.

Motorola MicroTAC cellular telephone.

Motorola MicroTAC cellular telephone, 1993. (Science Museum / Science & Society)

Today the battery that probably powers the phone in your pocket and the laptop on your desk is a Lithium battery, most likely a Lithium-Ion battery.

Introduced in 1990 these batteries have emerged as the best energy to weight ratio, meaning they last longer but weigh less, and they have enabled mobile phones to become smaller and smarter.

Sony Ericson T68i mobile phone, 2002. (Science Museum / Science & Society)

The iUnit concept car in our Plasticity exhibition is proof that in the future lithium batteries could be used to power even more aspects of our mobile lives.

Toyota i-Unit concept car, 2005 (Science Museum website)

No Laughing Matter

A Scientific Lecture, 1802

Gilray's 'A Scientific Lecture', 1802, depicts Humphry Davy 'bellowing' laughing gas

What have Humphry Davy, Mike Melvill and my dentist got in common? Answer: They’ve all exploited the chemistry of nitrous oxide, popularly known as ‘laughing gas’.

Davy experimented with euphoria-inducing properties of the gas with his friends Samuel Taylor Coleridge and James Watt. Davy was working at the Pneumatic Institution, set up by Thomas Beddoes to investigate the medical properties of inhaled or ‘factitous airs’. Davy pursued his experiments – part scientific, part recreational – with his normal con brio and was fortunate not to have seriously damaged his and others’ health.

Lucy Baldwin's Analgesic Apparatus, 1955-80

Lucy Baldwin's Analgesic Apparatus, 1955-80, mixed oxygen and nitrous oxide during midwifery (Science Museum/Science & Society)

My dentist, alongside doctors and medics, has long employed nitrous oxide as an analgesic, to relax patients and as a prelude to anaesthesia.

And Mike Melvill? Well, as pilot of SpaceShipOne, the world’s first privately developed spacecraft, he depended on its ability to oxidise rocket fuel for the thrust that carried him spaceward on his pioneering sub-orbital flight of 2004.

Dobson Ozone spectrometer, 1926

Dobson Ozone spectrometer, 1926. Dobson's technique for detecting ozone led to the discovery of the ozone hole over Antartica in 1985. (Science Museum/Science & Society)

So nitrous oxide has a variety of uses but it also has a dark side. Whether produced naturally or by industrial activity it leads to ozone depletion of the upper atmosphere. This lets in more of the Sun’s harmful ultra-violet radiation which the ozone molecules normally absorb. Plus, nitrous oxide acts as a particularly effective greenhouse gas, trapping the heat re-radiated from the Earth’s surface and causing global temperature rises.

No laughing matter indeed.