Page:Popular Science Monthly Volume 20.djvu/698

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for my wants," was delivered "Five fat sows and four feet"; a cricketing message from Lord's, "Jack, bring up two ground-men," was delivered "Jack bring up £2 10s." And, at the time that Commodore Goodenough was appointed to a station in Australia, the message received was, "A commodore has been appointed good enough for the Australian colonies." The system of telegraphy I have just shown is the ordinary one-way method; but it is possible to send two messages in the opposite direction at the same time upon one wire, and this I can make clear, without going into a detailed explanation, by asking Liverpool to send dashes or long sounds to me while I send dots or rapid sounds to him. [This was done.] We go still further, and send four messages in opposite directions, at the same time upon one wire; that is called quadruples telegraphy. But the acme of telegraphy has been produced in this country by the Wheatstone automatic apparatus. I have a complete set of this apparatus before me. In it the messages are prepared by being punched with little holes (as you now see being done), and I now hold a slip of paper bearing perforations representing the alphabet, which look very much like the patterns used in the Jacquard loom for lace-making. The perforated paper is put in the transmitter, which sends on currents of electricity, representing the holes upon it; these currents of electricity are received by a "receiver," by which they are made to represent dots and dashes recorded on a long slip of green paper, and these dots and dashes indicate to the clerk at the receiving station the message sent. The peculiarity of this instrument is its rapidity, for, by it, instead of being only able to send from thirty to forty words a minute (the limit of the human hand) from 250 to 300 words a minute can be transmitted. At the present moment, there is not a town in this country, where a daily paper is published, that is not in direct communication with London, and receives its intelligence by means of apparatus of this description. Whatever news it is, whether an account of the Canonbury Railway accident, or a panic that may have happened this afternoon in some theatre, or something else now going forward to the country papers, it is being sent by means of this perforated paper and automatic instrument. Those who are interested in the apparatus will be able to examine it closely at the end of the lecture; but it is impossible for me to describe it minutely now, because it would occupy more than one lecture to understand the whole working of the system. It is most extensively employed in this country, where the growth of telegraph business has been enormous. I spoke in somewhat glowing terms of the duties and doings of this automatic apparatus when in Paris, and my Parisian friends rather doubted my statement. However, I induced the French Government to send an officer over to England to examine for themselves the working of this instrument, and to my great pleasure when he came here he found that my statements were under the mark, and only a few days ago,