第28章 CHAPTER IV THE DEVELOPMENT OF THE ART(8)

"This may make your fortune," he said, "but no mechanic in Toledo can make a proper model of it for you. You must go to Chicago, where telegraphic apparatus is made." The boy gladly took his advice and went to the Western Electric factory in Chicago. Here he accidentally met Enos M. Barton, the head of the factory. Barton noted that the boy was a genius and offered him a job, which he accepted and has held ever since. Such is the story of the entrance of Charles E. Scribner into the telephone business, where he has been well-nigh indispensable.

His monumental work has been the development of the MULTIPLE Switchboard, a much more brain-twisting problem than the building of the Pyramids or the digging of the Panama Canal.

The earlier types of switchboard had become too cumbersome by 1885. They were well enough for five hundred wires but not for five thousand.

In some exchanges as many as half a dozen operators were necessary to handle a single call;and the clamor and confusion were becoming unbearable. Some handier and quieter way had to be devised, and thus arose the Multiple board.

The first crude idea of such a way had sprung to life in the brain of a Chicago man named L.

B. Firman, in 1879; but he became a farmer and forsook his invention in its infancy.

In the Multiple board, as it grew up under the hands of Scribner, the outgoing wires are duplicated so as to be within reach of every operator.

A local call can thus be answered at once by the operator who receives it; and any operator who is overwhelmed by a sudden rush of business can be helped by her companions. Every wire that comes into the board is tasselled out into many ends, and by means of a "busy test," invented by Scribner, only one of these ends can be put into use at a time. The normal limit of such a board is ten thousand wires, and will always remain so, unless a race of long-armed giantesses should appear, who would be able to reach over a greater expanse of board. At present, a business of more than ten thousand lines means a second exchange.

The Multiple board was enormously expensive.

It grew more and more elaborate until it cost one-third of a million dollars. The telephone men racked their brains to produce something cheaper to take its place, and they failed.

The Multiple boards swallowed up capital as a desert swallows water, but THEY SAVED TEN SECONDSON EVERY CALL. This was an unanswerable argument in their favor, and by 1887 twenty-one of them were in use.

Since then, the switchboard has had three or four rebuildings. There has seemed to be no limit to the demands of the public or the fertility of Scribner's brain. Persistent changes were made in the system of signalling. The first signal, used by Bell and Watson, was a tap on the diaphragm with the finger-nail. Soon after-wards came a "buzzer," and then the magneto- electric bell. In 1887 Joseph O'Connell, of Chicago, conceived of the use of tiny electric lights as signals, a brilliant idea, as an electric light makes no noise and can be seen either by night or by day. In 1901, J. J. Carty invented the "bridging bell," a way to put four houses on a single wire, with a different signal for each house. This idea made the "party line" practicable, and at once created a boom in the use of the telephone by enterprising farmers.

In 1896 there came a most revolutionary change in switchboards. All things were made new. Instead of individual batteries, one at each telephone, a large common battery was installed in the exchange itself. This meant better signalling and better talking. It reduced the cost of batteries and put them in charge of experts. It established uniformity. It introduced the federal idea into the mechanism of a telephone system. Best of all, it saved FOURSECONDS ON EVERY CALL. The first of these centralizing switchboards was put in place at Philadelphia;and other cities followed suit as fast as they could afford the expense of rebuilding.

Since then, there have come some switchboards that are wholly automatic. Few of these have been put into use, for the reason that a switchboard, like a human body, must be semi-automatic only. To give the most efficient service, there will always need to be an expert to stand between it and the public.

As the final result of all these varying changes in switchboards and signals and batteries, there grew up the modern Telephone Exchange.

This is the solar plexus of the telephone body.

It is the vital spot. It is the home of the switchboard.

It is not any one's invention, as the telephone was. It is a growing mechanism that is not yet finished, and may never be; but it has already evolved far enough to be one of the wonders of the electrical world. There is probably no other part of an American city's equipment that is as sensitive and efficient as a telephone exchange.

The idea of the exchange is somewhat older than the idea of the telephone itself. There were communication exchanges before the invention of the telephone. Thomas B. Doolittle had one in Bridgeport, using telegraph instruments Thomas B. A. David had one in Pittsburg, using printing-telegraph machines, which required little skill to operate. And William A. Childs had a third, for lawyers only, in New York, which used dials at first and afterwards printing machines. These little exchanges had set out to do the work that is done to-day by the telephone, and they did it after a fashion, in a most crude and expensive way. They helped to prepare the way for the telephone, by building up small constituencies that were ready for the telephone when it arrived.