Section 1: Morse and his Code

In 1844, an American called Samuel Finley Breese Morse sent the first message over a telegraph line between Baltimore and Washington in the United States, using a signalling code of his own invention. The message read "What hath God wrought?"

There had been other telegraph systems before Morse; in particular the Englishman Charles Wheatstone had developed a system using the deflections of a needle which was used in railway signalling. Both Wheatstone and Morse were indebted for their basic ideas to the American, Joseph Henry, who however did not patent his inventions.

But what made Morse's system different, and what caused it to be the telegraph system universally employed, were two factors: firstly, Morse's ability to lobby the United States Congress and convince them to pay for the construction of the first commercial telegraph line; and secondly, the simplicity and ease of the "Morse Code". Skilled operators could eventually send messages in code at up to thirty words a minute.Morse's basic telegraph system was extremely simple: the operator opened or closed a switch (known as the "key") to send electricity from a battery along the telegraph wire - the return path for the current was through the ground. At the receiving end, the pulses of current operated a pen which marked a strip of paper (later known as "ticker tape") whenever current was present. Later, skilled operators found they could spell out the message just listening to the sound that the pen made, and eventually the marker was amplified by a mechanism to amplify the sound.

The problem was how to use these pulses of electrical current to represent the letters of the alphabet and to spell out a message.

Morse decided that the best way was to use two different kinds of electrical pulse - one short and one long, a dot and a dash. By combining these two kinds of pulses, it was possible to represent every letter in the alphabet by a code of four pulses or less.

He made a careful study of the frequencies of different letters of the alphabet used in printing by examining the numbers of each letter kept in typesetters' print trays. He then gave the letters which were most frequent the shortest codes. In this way, the number of pulses that had to be sent to communicate an average sentence in English could be kept to the minimum.

Thus the letter "E", which is the most commonly used letter in English, was given a Morse Code of a single dot. The next most common letter, "T", was represented by a single dash. Less common letters were combinations of dots and dashes. Numerals and punctuation marks were made up of combinations of five and six pulses respectively.

There was a strict set of rules governing how to send messages in Morse Code. A dash was to last as long as three dots. A space as long as one dot was left between the pulses making up the same letter. A space as long as one dash was left between different letters, and a space as long as five dots was left between different words.

Although all this starts to sound very complicated, in practice operators soon found they could send and receive the messages with increasing speed and reliability. In a very short time, Morse's telegraph system became adopted in almost every industrial country in the world.

The first telegraph line to be erected in Australia was in 1854, between Melbourne and Sandridge (now Port Melbourne). Other lines in other colonies quickly followed.

Adelaide, Melbourne and Sydney were joined by telegraph in 1858. In 1859, a submarine cable was laid from Victoria to Tasmania. Brisbane was connected to Sydney in 1861, and Queensland began to push its lines rapidly northward. Perth, beyond the barrier of the Nullarbor Plain, took rather longer to be connected with the other colonies, waiting until 1877.

In 1872, the colony of South Australia pushed a line through the very centre of Australia to Darwin in order to connect with a submarine cable from Java which then connected with the now extensive telegraph systems of Europe, and so putting Australia in contact with England and the rest of the world.

Much later, around the turn of the century, when the Italian inventor, Gugliemo Marconi was developing radio (or "wireless telegraphy" as it was then called), Morse Code was still used to send messages using the new communications method. This was largely because of the simplicity of the method of transmission compared with other methods, and particularly compared with the problems of transmitting the human voice.

So on a wintry December day in 1901 in Newfoundland, it was a letter of the Morse alphabet - the three dots of the letter "S" - that Marconi heard in his earphone, a signal transmitted against all predictions of the experts across the Atlantic Ocean from England. It was a very faint signal, but Marconi could pick it out against all the background noise.

It is this recognisability of Morse signals in situations of high noise and low transmitting power that has ensured the continuing use of Morse's Code in such situations right up to the present day.

Morse Code Chart