Text 2. Faraday's discoveries

Michael Faraday, who was born in 1791 and died in 1867, gathered together and set in order all the work of the scientists who had worked on electrical problems before him.

In 1823 he discovered how to make an electrical motor. In 1831 he built the first generator, then called it dynamo. The modern car has both a starting motor and a generator. The starting motor draws electric current from the car battery to start the powerful gasoline engine. The generator is driven by the gasoline engine to recharge the battery and to furnish electrical power for all the electrical conveniences in the car.

Faraday's experiments of August 29, 1831, gave us the principle of the electric transformer, without which the later discoveries of that fateful year could have little real practical application. For to convey the electric current over long distances, say to supply a town, or feed an electric railway, it is necessary to generate it at a very high voltage, or force. By means of transformers based on Faraday's induction coil discovery, it is simple for a current direct from a power-station of say

132.000 volts to be stepped down for the electric train to 600 volts and for household use to 240 volts. The procedure is quite simple. The current is fed into the transformer across the primary, or input coil, which corresponds to Faraday's right-hand coil on his induction ring. The resultant induced current is taken from the secondary, of output coil, which corresponds to Faraday's left-hand coil. If this secondary coil has more windings of wire than the primary coil, the voltage will be stepped down.

So the two related discoveries of 1831 provided not only the means of making electricity easily and cheaply, on as large a scale as required, without any cumbersome batteries, but also the way of using it in a safe and practical way.

In 1833 Faraday discovered the effects of passing an electric current through certain solutions, he called this effects the laws of electrolysis. This has made possible the refinement of metals, silver and gold plating, and the manufacture of many chemical products.