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- British engineers: Denis Johnson
- Channel 4, Sunday, 7.05pm: Chasing Perfection
- BBC One, Sunday, 2.20pm & 9pm: The Hunt
- Free course: James Clerk Maxwell
Got some spare time this weekend? Why not discover James Clerk Maxwell, the man who created the unified theory of electromagnetism:
This unit presents Maxwell's greatest triumph – the prediction that electromagnetic waves can propagate vast distances through empty space and the realisation that light is itself an electromagnetic wave. Visible light has a very narrow range of wavelengths, but this tells us more about the sensitivity of our eyes than about the nature of electromagnetic radiation. A few years after Maxwell's death other types of electromagnetic radiation, including radio waves, X-rays and gamma rays, were discovered. Compared to light, radio waves have very long wavelengths, while X-rays and gamma rays have very short wavelengths. Different parts of the electromagnetic spectrum are used in different ways. Radio waves are used for broadcast radio and television, satellite communications and mobile phones. Gamma rays are used to treat cancer and X-rays are used in medical diagnosis. Yet all these waves have the same underlying description in terms of electric and magnetic fields.
Two slices of natural history goodness on BBC One from the OU this Sunday. In the afternoon, a second chance to see The Hunt from last week, exploring predators in the ice. Then, a brand new episode in the evening takes us into the forest.
A new series from the Open University this weekend - on Channel 4, our third partnership with the channel. It's Chasing Perfection, and it explores the role that science has played in improving performance of sports people over the last two decades:
Over the two episodes Michael will meet some of the best athletes and talk to leading high performance experts and sports scientists to look at some of the unique factors that takes this vast population of the globe and from it forms a tiny band of athletes who have what it takes to perform at the highest level.
This week, we've been celebrating the lives of some British engineers. Here's a quick recap of who we've featured so far:
- John Barraclough Fell, who took trains up mountains
- Beryl Platt, one of the first female aeronautical engineers
- Christian Galloway, who opened up coal fields around the world
- George Jennings, who invented the flushing toilet
To round off the week, we're meeting Denis Johnson, who improved a design and sparked a craze.
This summer the news has been full of stories of a modish mode of two-wheeled transport which has been met with a mix of trend-hopping joy and warnings of how dangerous it all is. Two hundred years before the Hoverboard, though, Denis Johnson created a stir with his pedestrian curricle - delighting the dandies of the day, but attracting warnings of severe risk to life and limb.
Johnson, a carriagemaker in Long Acre, London, wasn't the inventor of the velocipede - they'd been popular on the continent for a while - but worked with the German Baron DeDrais to improve the design of the two-wheeled proto-bike. These devices were propelled not by pedals, but by the rider striding down the path (kind of like The Flintstones' car); Johnson's enhancements included curving the frame, allowing for larger wheels, and thus faster speeds.
Having secured a patent for his design in 1818, Johnson set about building a solid business. Dubbed hobby horses, dandy horses, pedestrian's accelerators and even swift walkers, they weren't cheap - retailing for about a tenner a throw (about six hundred pounds in modern terms) - but they were popular. Johnson sold over 300, helped by his talent as a marketeer being as acute as his skills as an engineer - he created a buzz, for example, by opening a school for cyclists, and tweaked his design to make a lady version which accomodated long skirts.
The fashion would not last long, however, and by 1819 hobby horses were becoming the subject of public ire, satirist's pens and doctor's warnings. London banned riders from the pavement:
The crowded state of the metropolis does not admit of this novel mode of exercise, and it has been put down by the Magistrate of police
But even as the trend waned, in France, other inventors were looking at Johnson's design and wondering what would happen if, instead of using your feet on your ground, you had something to push the wheels around with...