Ever wondered what were the greatest experiments ever conducted? Well, here's some of the top ten for you.
1. Galileo Galilei (1564 to 1642)
Legend has it that in order to test how gravity worked, Galileo dropped two balls, a heavy one and a light one, from the Leaning Tower of Pisa, showing that they landed at the same time. Historians doubt this - because his actual experiment was much better.
The Italian carved a groove down the centre of a board about 20 feet long and 10 inches wide. Then he propped it at an angle and timed how quickly the balls rolled down the track. What he discovered was that the distance the ball travels is proportional to the square of the time that has elapsed.
But how, in an age before clocks, could Galileo measure this so precisely? He probably used music. Along the ball's path, he placed cat-gut frets, like those on a lute. As the rolling ball clicked against the frets, Galileo sang a tune, using the upbeats to time the motion and discover a new law.
3. Isaac Newton (1642 to 1727)
In Newton's day, Europe's great scientists believed that white light was pure and fundamental. When it bounced off a coloured object or passed through a tinted liquid or glass, it became stained somehow with colour - whatever "colour" was.
Newton, holed up in a dark room at his family farm in Woolsthorpe, turned the idea on its head. He cut a hole in his window shutter and held a prism in the path of the sun, spreading the light into an oblong spectrum. Then he funnelled the spectrum through a second prism. White again.
Finally, he allowed the colours to pass, one by one, through the second prism. Starting at the red end and progressing toward the blue, each colour was bent a little more by the glass. Light, Newton had discovered, "consists of rayes differently refrangible". It was white that was the mongrel - not just another colour, but a combination of them all, a "heterogeneous mixture of differently refrangible rayes".
6. Michael Faraday (1791 to 1867)
In his youth, Faraday had performed a suite of experiments showing the linkage between electricity and magnetism, inventing, along the way, the electric motor and the dynamo. But by the time he was 53, he had fallen into a deep depression.
Maybe it was a barrage of flirtatious correspondence from Lady Ada Lovelace, the daughter of Byron, that snapped him out of his funk: whatever the cause, he decided to push the unification a step further, and show that electricity and magnetism are related to light.
Using an Argand oil lamp, Faraday projected polarised light through a block of glass, alongside of which sat a powerful electromagnet. Holding a polarising filter, called a Nicol prism, to his eye, he rotated it until the light was extinguished. Then he switched on the current.
The image of the flame suddenly reappeared. He turned the magnet off and the flame disappeared. The magnetic field, he realised, was twisting the light beam - and if the polarity of the field was reversed, the light beam rotated the other way. Faraday had unified two more forces, demonstrating that light was actually a form of electromagnetism.
Anyone of you planning to be added to the list anytime soon? ;)
