Part 94

The great Marathon runner was nothing more or less than a telegraph messenger hastening with his written message, from the man who delivered it to him, to its destination, and his work was harder than that of the messenger boy to-day, for he not only had to deliver the message himself to its destination, but had to run fast all the way or lose his job.

The messenger on foot finally gave way to the Pony Telegraph, which not only shortened the time necessary to deliver a message, but marked the beginning of a system.

How Does a Telegram Get There?

The next time your daddy takes you down to the office, ask him to show you the telegraph call box. When you see it, you will perhaps not think that by merely pulling down the little lever you can so start things going that, if you wish, you can cause men who are on the other side of the earth to work for you in a few minutes, and to make little instruments all along the way which, with their other equipment, have cost millions of dollars, click, click, click at your will.

Here we see the messenger calling at the office from which the call box registered a call and receiving the telegram to be taken by him to the central office to be put on the wire.]

Sooner or later during the day your father will be wanting to send a telegram. He steps to the call box, pulls the little lever and goes back to his desk. In a few minutes, sometimes before you realize it, the little blue-coated messenger appears and says “Call?” Father hands him a telegraph blank on which he has written the message, the messenger takes off his cap, puts the message inside and the cap back on his head and away he goes on his bicycle as fast as his legs can pedal, to the central office, to which point you follow him to see what he does with the message.

If you had been at the telegraph office instead of your father’s office, you would have seen one of these boys start off on his wheel to get the message your father wished to send. When the little lever on the call box is pulled down, it is pulled back by a spring which sets some clock work going which sends a signal over the wire on a circuit which runs out from a register at the main office. The register has a paper tape running through it, and the signal from the call box appears as a series of dots on the tape. The clerk knows from the number and spacing of the dots that it was your father that called and not some other business man whose box might be on the same circuit.

We have now followed the telegram to the point where it is to start on its real journey. Here we see the operator preparing to send the message. He first must “get the wire.” By this is meant to get a through connection to the town where the message is to be delivered. Each office along the line has a signal. The other operators can hear the call, but since it is not their signal, they pay no attention. Almost immediately, however, the operator at the delivery point hears the signal. He signals back “I I” and repeats his own office call, which means “I hear you and am ready.” The message is then ticked off, until finished and the operator at the delivery point signals “O. K.,” together with his personal signal, which means he has received the whole message and has it down on paper.]

Here we see the messenger delivering the telegram to the person to whom it is addressed. It may be good news or bad news for the person receiving it, but it is all in the day’s work for the messenger boy. But let us see how many people have to work to deliver the message. We have followed it through from the original call box. First there was the messenger who came for it, then the receiving clerk, the sending operator and the operator who receives it and last of all the messenger boy who delivered it. This does not take into account the men who must look after the many miles of wires, the machinery which supplies the current, or the great army of men who are constantly laying new wires so that you can send a telegram from almost anywhere to any other place.]

The operators you have seen working in these pictures are Morse operators. They send the message by Morse Code in dots and dashes which are sent over the wire as electric impulses. At the other end the message is read by listening to the clicks the sounder makes as it receives these same electric impulses. This is the simplest way of telegraphing.

The number of messages sent between two big cities in a day is tremendous--many more than could be transmitted over one Morse wire. Many wires would be needed. But wire costs money, so ingenious men set to work to find some way to send more than one message over a single wire at the same time. They succeeded. There is now the duplex telegraph, which sends a message each way simultaneously over a single wire, the quadruplex, which sends two messages each way simultaneously over a single wire. Last but not least there is the multiplex, which sends four messages each way simultaneously over a single wire. This seems almost unbelievable, but it is done. In the case of the duplex and quadruplex, the different messages are sent by currents of different strength, and by changing the direction of the current. Receiving instruments are designed so as to separate the messages by being affected only by the currents of certain strength or polarity, as the direction of flow is termed. It can easily be seen that by these ingenious devices, the telegraph company saves many thousands of dollars in the miles and miles of wire, and hundreds of telegraph poles which would be required if all the messages had to be sent over a simple Morse wire, one message only upon the wire at a time.

In this picture we see the interior of a telegraph office along the line of a railroad. The operator has her hand on the “key” or sending instrument. At her left in a stand called the resonator, is the receiving instrument called the “sounder” which clicks off the message. In front of her is an instrument called the “relay.” Current from two of the batteries goes through the key when it is pressed down, through the relay and out on to the wires of the pole line, then through the relay of the receiving operator at the other end, (see picture on opposite page) through his key and through two more batteries to the ground. The earth forms the return wire of an electric circuit when both keys are “closed” or pressed down. You know all electricity has to flow in a closed circuit. The “sounder” has to make good strong clicks to be understood, and the current after it has gone through miles of wire and ground may not be strong enough so the sounder is put on a local circuit of its own, with a special battery. In this circuit is a contact maker which is part of the relay. When the key is pressed down and current flows over the wires on the poles and through the relays, the magnets of the relay pull on a little piece of metal called the “armature,” which makes a contact and closes the local sounder circuit, so current from the single local battery can flow up through the magnets of the sounder and back to the battery. This makes the sounder click. When the key is released, the relay armature is pulled back by a spring and breaks the circuit of sounder, which then emits another click. By the number and duration of the clicks and the time between them, the receiving operator knows the meaning of the signal. The Morse Code, which is used throughout the United States, is shown on next page.]

MORSE TELEGRAPH CODE

Letters Morse A · -- B -- · · · C · · · D -- · · E · F · -- · G -- -- · H · · · · I · · J -- · -- · K -- · -- L ---- M -- -- N -- · O · · P · · · · · Q · · -- · R · · · S · · · T -- U · · -- V · · · -- W · -- -- X · -- · · Y · · · · Z · · · · & · · · ·

Numerals

Figures Morse 1 · -- -- · 2 · · -- · · 3 · · · -- · 4 · · · · -- 5 -- -- -- 6 · · · · · · 7 -- -- · 8 -- · · · · 9 -- · · -- 0 ----

Punctuations

. Period · · -- -- · · : Colon -- · -- · · ; Semicolon · · · · · , Comma · -- · -- ? Interrogation -- · · -- · ! Exclamation -- -- -- · - Fraction Line · ¶ Paragraph -- -- -- -- () Parenthesis · -- ·· --]

The multiplex telegraph is truly a marvellous invention. It has been developed by the engineers of the Western Union Telegraph Co. working with the engineers of the Western Electric Company. The principle on which this instrument works is that if separate instruments are given connection with the wire one after the other during very short intervals of time, the effect is as though the wire were split up, and each instrument works just as if it alone were on the wire. Not only does the multiplex telegraph thus send four messages in one direction and four messages in the opposite direction, simultaneously over a single wire, thus keeping no less than sixteen operators employed on one wire, four sending and four receiving at each end, but each message instead of being sent by the ordinary Morse key, is written upon a typewriter keyboard at one end of the line and appears automatically typewritten at the other end.

If you live in a big city, go into one of the larger branch offices of the Western Union Telegraph Co. and ask to see printing telegraph. Most of the large branch offices communicate with the general operating department in the city by means of what they term “short line printers,” which are instruments on which the message is written upon a typewriter keyboard and appears typewritten at the other end.

Who Invented the Electric Telegraph?

It is hard to say just how the telegraph originated in the mind of men. We have already shown how the savages sent signals over distances by means of the smoke rising from his fire. Every boy and girl has used a little mirror, held in the sun to flash a bright spot here and there. This principle has been used by the army to signal at distances. The sun’s rays are flashed from a small mirror, long and short flashes indicating the dashes and dots of the Morse telegraph code.

Progress towards the perfection of the electric telegraph began with the first researches of scientists into the natural laws which govern that great natural agent, electricity. Clever, painstaking men, studying and experimenting for the love of the work, discovered bit by bit how to control the force. Stephen Gray with his Leyden jars, which stored up a charge of electricity, inspired Sir William Watson to experiment, and he sent current from one jar to another two miles away.

The First Suggestion of the Electric Telegraph.

For a long time no one thought that this opened the way for the making of a useful servant for man. In 1753 this thought occurred to an unknown man in Scotland, who wrote a letter to a newspaper suggesting that messages be sent by electric currents.

One of his schemes was that there should be a light ball at the receiving end of the wire which would strike a bell when it felt the electric impulse come over the wire from the Leyden jar, and by devising a code depending upon the number of strokes of the bell and the time between them, he suggested that messages could be sent and interpreted. Some believe this man to have been a doctor named Charles Morrison of Greenock, Scotland. Whoever he was, he suggested a method which comes very near to being that in use to-day.

The difficulty with proceeding on this suggestion was that the current from the Leyden jar was static electricity, which has not the strength nor can it be controlled as can the current of low potential which is used to-day. Volta discovered this new and more stable form of electricity and many different men labored investigating what could be accomplished with it. The names of Sir Humphry Davy and Michael Faraday are inseparably connected with this advance. It was Oersted’s and Faraday’s discovery of the connection between electricity and magnetism, and how an electric current may be made to magnetize a piece of iron at will, that really opened the way for the invention of the telegraph we know to-day.

The First Real Telegraph.