ELECTRICITY & MAGNETISM
VOLT'S PILE - Thousands of years ago man knew about electricity, but not enough to do anything positive with the curiosity. It would not be until electricity could be applied to lighting, that it would become commercially important, and traded, just as oil lamps made whalers rich, consigning candles to the emergency cupboard. Gas lamps too would be displaced, where electric lighting was safer and brighter.
The Greeks knew the magnetic properties of the mineral lodestone, sometimes called Magnetite, as early as 600 B.C. Thales Miletus (640 - 540 B.C.), an early Greek mathematician and astronomer, was aware of the properties of attraction and repulsion of lodestone with like pieces of lodestone. He too knew of an electrostatic effect called the amber effect, that is, the attraction of bits of straw to an amber rod that had been rubbed with wool.
In 1801 Alessandro Volta demonstrated his ‘Pile’ to Napoleon. The pile was a series of copper and zinc discs interleaved with moist cloth, to form an electric battery.
Twenty years later in 1821 Michael Faraday invented a simple single-wire electric motor and then in October 1831 Faraday succeeded in generating an electric current mechanically. He had invented the dynamo using a bar magnet and a coil of copper wire.
Michael Faraday's experiment to show magnetic induction. A battery (right) is used to power a coil (A) to make an electro-magnet, that is inserted into another coil (B) that then generates a current, visible on the Galvonometer (C).
Faraday's disc. The first electricity generator.
JAMES CLERK MAXWELL
The laws of electricity and magnetism were closely studied by James Clerk Maxwell (1831 –1879), a Scottish physicist. Maxwell wondered why the physical laws were not symmetric when
expressed in mathematical form. By applying the concept of symmetry, he found an additional law, which completed the equations of electromagnetism in 1865.
Electric motors can turn impellor pumps to pump water uphill, and water can be fed through impellors to turn generators, such as in a hydroelectric dam. Once again, as with generators and motors, to greater or lesser degrees machinery can be reversible. This is the basis of regenerative braking on modern electric vehicles. The motors of which are remarkably efficient Direct Current synchronous machines, bearing little resemblance to Faraday's experiments.
Modern batteries can be very much larger that Volta's Pile, typically made of lithium, cobalt, and polymers. These batteries not only power EVs, but also store electrical energy in bulk, to stabilise the National Grid, to provide load levelling, just like at the Generating Works at Herstmonceux. The world's first stabilised municipal supply, and the only example remaining, anywhere in the world.
A hive of local activity, in the Sussex backwater of Herstmonceux. The driver from all of this was electric lighting, to replace candles and gas lighting.
The machinery at Herstmonceux Generating Works was gas powered in its final guise. The gas coming from heating coal. Hence, the sizeable brick built bunker, convenient to shed number three, where the (town) gas maker plant was installed. The complex is interesting because it not only generated electricity, but stored it in Shed number One, a room filled with large glass lead-acid batteries, with sufficient capacity to provide electric lighting and cooking to the village, in 1913.
If you know of any information that may help us complete this story, please get in touch.
Copyright © 2023 Lime Park Heritage Trust. A not for profit organisation with charitable objects.