We have been looking at the history of electricity for this blog post, and by co-incidence, this has been the subject of a documentary series on BBC Four called “Shock and Awe: The Story of Electricity”
It was always known from historic times that certain substances such as amber could be rubbed and would attract small items, like feathers. The Greek word for amber is “electron” from which the word electricity comes. In the 17th Century, scientists started to experiment with electricty, and to help with these experiments, Otto von Guericke created the first reliable device that could generate static electricity. This was a globe (made out of sulphur) that could be rubbed by hand.
Benjamin Franklin (1706-1790) was a scientist and politician who was one of the founding fathers of the United States. Benjamin conducted experiments on a number of scientific areas, including electricity, but he was most famous for his experiment with a kite in 1752, when he fastened a metal key to the bottom of a kite string and flew it during the build up to an electrical storm.
When he found that sparks were jumping from the key onto his hand, it proved to him that lightning was a form of electricity and this led to the invention of the lightning conductor that you see on many buildings.
Italian anatomy professor Luigi Galvani (1737-1798) experimented with electricity in 1771 by fastening the legs of a frog to a copper hook and attached the hook to an iron railing. The frog’s legs twitched violently, and he mistakenly concluded that the muscles of the frog must contain electricity!
Alessandro Volta (1745 – 1827) looked at Galvini’s work with a frog and realised that the frog’s legs were twitching as they were conducting electricity between the copper and the iron. This started a rivalry between the two scientist, and it inspired Volta to create the first battery using zinc and copper, similar to Galvini’s test, to show that electricity did not come from the frog’s legs!
You can make a battery like Volta’s using a lemon! To make this, squeeze the lemon, to get the juice moving, put a piece of copper (or even a copper coin) and a piece of zinc into the lemon, and attach these by pieces of wire to a LED (light), and hey presto! The light should come on!