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Les informations fournies dans la section « Synopsis » peuvent faire référence à une autre édition de ce titre.
In this work the aim has been to give a detailed exposition of the various systems of telegraphy in use in America at the present time, together with a complete description of modern methods of operation, and an extensive compilation of the formulae used in practical telegraphy. One occasionally hears it remarked that since the practical introduction of the quadruplex about thirty years ago there have been no important developments in telegraphy, but those who have been engaged in the work of improving telegraph apparatus and operating methods are well aware that even since the last American book dealing with this subject was written several years ago, material progress has been made in several directions. The fact that to-day eighty telegrams per hour are handled over a single Morse outlet where ten years ago half that number in the same time was considered good performance, and that during the same period the time of transmission of a telegram between cities remotely separated has been reduced at least one-half, cannot but be regarded as convincing evidence that vast improvement has taken place. One factor that has contributed largely to the improvement in the service is the increasing technical knowledge of the men engaged in operating the plant; and this, in spite of the fact that the production of technical telegraph literature has not kept pace with the actual development of the art. In the present work the author has incorporated all of the elemental essentials of the general subject as well as all of the new departures which have made for betterment, and an attempt has been made to treat the various divisions of the subject in terms that should make it possible for the student, by due exercise of diligence, to qualify himself for the most advanced positions in the service. I ncidentally, it might here be stated that it is no longer possible for the t
(Typographical errors above are due to OCR software and don't occur in the book.)
Les informations fournies dans la section « A propos du livre » peuvent faire référence à une autre édition de ce titre.