When the great Elizabethan experimenter William Gilbert, after many years' work, published his book De Magnete, and first defined scientifically a number of fundamental ideas about magnetism and electricity, he started a chain of operations that eventually led to the vast, dynamic and complex electrical engineering industry of today which consumes two million tons of copper annually. It was Gilbert incidentally who coined the word 'Electrica' from the Greek word elektron, meaning amber, a substance which featured in his experiments.
Electrical engineering in the industrial sense is only about a hundred years old and followed from Faraday's epoch-making discovery of electromagnetic induction in 1831; its roots, however, extend back much earlier, even before Volta's famous 'pile' of 1800, when the relative values of metals as conductors of electricity were well known. The success achieved by using copper in these classic experiments led to its general use in this field long before the theoretical reasons were understood. Hence all the early experimenters soon found themselves using copper sheets and wires whilst brass, because of its non-magnetic properties and ease of working, was specified for structural parts.
A notable milestone in early electrical research was the invention of the Leyden jar in 1745. Two years later Sir William Watson, who was deeply interested in electrical phenomena, succeeded in transmitting a current 2410 feet across Westminster Bridge, using the River Thames as the return circuit. He also noticed that the effect was apparently instantaneous. Stephen Gray had already found that some bodies conducted electricity well, whereas others did not, the first conception of dielectrics; and in 1729 he used brass wire for the first known attempt to transmit an electric current. Thus began a series of experiments by a number of investigators to determine which were the best transmitters of the 'electric fluid', as it was called: it was soon proved that metals were the most successful and that of these, copper, even in its relatively impure state, was superior to all others except silver.