he first time the
relationship between magnetism and electricity was in fact an
accident.

While lecturing to students he showed them that the current
flowing in a wire held over a magnetic compass needle and at right
angles to it (that is east-west) had no effect on the needle. Oersted
suggested to his assistant that he might try holding the wire parallel
to the length of the needle (north-south) and hey presto, the needle
was deflected! He had stumbled upon the electromagnetic effect in the
first recorded instance of a wire behaving like a magnet when a
current is passed through it.

A development of Oersted's demonstration with the compass needle
was used to construct the world's first system of signaling by the
use of electricity.

In 1837 Charles Wheatstone and William Cooke took out a patent for
the world's first Five-needle Telegraph, which was installed between
Paddington railway station in west London and West Drayton station a
few miles away. The five copper wires required for this system were
embedded in blocks of wood.

Electrolysis, the chemical decomposition of a substance into its
constituent elements by the action of an electric current, was
discovered by the English chemists Carlisle and William Nicholson
(1753-1815). If an electric current is passed through water it is
broken down into the two elements of which it is composed--hydrogen
and oxygen. The process is used extensively in modern industry for
electroplating. Michael Faraday (1791-1867) who was employed as a
chemist at the Royal Institution, was responsible for introducing many
of the technical terms connected with electrolysis, like electrolyte
for the liquid through which the electric current is passed, and anode
and cathode for the positive and negative electrodes respectively. He
also established the laws of the process itself. But most people
remember his name in connection with his practical demonstration of
electromagnetic induction.

In France Andre-Marie Ampere (1775-1836) carried out a complete
mathematical study of the laws which govern the interaction between
wires carrying electric currents.

In Germany in 1826 a Bavarian schoolmaster Georg Ohm (1789-1854)
had defined the relationship between electric pressure (voltage),
current (flow rate) and resistance in a circuit (Ohm's law) but 16
years had to elapse before he received recognition for his work.

Scientists were now convinced that sin