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Wireless Transformations: Studies in the History of Science and Technology Jed Buchwald, General Editor

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Wireless Transformations: Studies in the History of Science and Technology Jed Buchwald, General Editor Wireless Transformations: Studies in the History of Science and Technology Jed Buchwald, general editor Sungook Hong, Wireless: From Marconi’s Black-Box to the Audion Myles Jackson, Spectrum of Belief: Joseph von Fraunhofer and the Craft of Precision Optics William R. Newman and Anthony Grafton, editors, Secrets of Nature: Astrology and Alchemy in Early Modern Europe Alan J. Rocke, Nationalizing Science: Adolphe Wurtz and the Battle for French Chemistry Wireless From Marconi’s Black-Box to the Audion Sungook Hong The MIT Press Cambridge, Massachusetts London, England © 2001 Massachusetts Institute of Technology All rights reserved. No part of this book may be reproduced in any form by any electronic or mechanical means (including photocopying, recording, or information storage and retrieval) without permission in writing from the publisher. Set in Sabon by The MIT Press. Printed and bound in the United States of America. Library of Congress Cataloging-in-Publication Data Hong, Sungook. Wireless : from Marconi’s black-box to the audion / Sungook Hong. p. cm. — (Transformations: studies in the history of science and technology) Includes bibliographical references and index. ISBN 0-262-08298-5 (hc. : alk. paper) 1. Radio—History. I. Title. II. Transformations (MIT Press) TK6547 .H66 2001 384.5'2'09034—dc21 2001030636 to my family This page intentionally left blank Contents Preface ix Acknowledgments xv 1 Hertzian Optics and Wireless Telegraphy 1 2 Inventing the Invention of Wireless Telegraphy: Marconi versus Lodge 25 3 Grafting Power Technology onto Wireless Telegraphy: Marconi and Fleming on Transatlantic Signaling 53 4 Tuning, Jamming, and the Maskelyne Affair 89 5 Transforming an Effect into an Artifact: The Thermionic Valve 119 6 The Audion and the Continuous Wave 155 Epilogue: The Making of the Radio Age 191 Appendix: Electron Theory and the “Good Earth” in Wireless Telegraphy 193 Notes 199 Bibliography 229 Index 245 This page intentionally left blank Preface As late as 1850 there was no awareness of electromagnetic waves. In the 1860s, the British physicist James Clerk Maxwell theorized the existence of electromagnetic disturbances in the ether whose wavelengths were longer than those of infrared radiation. The followers of Maxwell who came to be known as the British Maxwellians concentrated on producing electromag- netic waves. In 1882–83, George FitzGerald and Oliver Lodge concluded that Maxwell’s electromagnetic waves could be emitted from rapid electric oscillations produced by the discharge of a condenser or a Leyden jar, but they lacked an adequate device with which to detect this radiation. In 1887–88, while Lodge was working on the oscillatory effect along wires, the German physicist Heinrich Hertz, working under the influence of Hermann von Helmholtz, succeeded in producing and stabilizing a new effect of sparks, which he soon identified as electromagnetic waves. Within a year, the British Maxwellian Oliver Heaviside exclaimed: “Not so long ago [electromagnetic waves] were nowhere; now they are everywhere!” (Heaviside 1892, volume II, p. 489) Scientists and engineers began specu- lating more concretely about the possibility of wireless communication, long dreamed of by many. In 1892, William Crookes offered a futuristic vision of wireless commu- nication in a popular article (Crookes 1892). In 1895–1897, Hertzian wave telegraphy practical enough for communication was invented and patented by Guglielmo Marconi. Marconi’s achievement inspired others; in 1897, for example, the British electrical engineer William Ayrton imagined a future in which anyone could call a friend “in an electromagnetic voice” and the friend could reply “I am at the bottom of the coal mine, or cross- ing the Andes, or in the middle of the Pacific” (Ayrton 1897). Soon amateur wireless operators were communicating by means of wireless telegraphy, x Preface and by 1910 a young amateur wireless operator, Edwin Howard Armstrong, could note casually: “For the last two weeks I have been call- ing A. P. Morgan with my 2 K.W., but have not yet picked him up. I think he is probably out of town as I used to hear his 3 K.W. every night a few months ago.” (E. H. Armstrong to Mr. Underhill, 2 Dec. 1910, Armstrong Papers, Columbia University) Fifteen years after Marconi’s invention, wire- less telegraphy had become an essential means of communication, as well as a hobby for many. The popular history of wireless telegraphy is a history of adventure. Many of us, as children, read with wonder the story of an Italian teenager’s experiment that went unrecognized by his father, his move to Britain at 22, the accidental breakage of his instrument by British customs, the “secret- box” that astonished famous British scientists, his reception of transatlantic messages with a kite at age 27, and the heroic role of wireless telegraphy in the Titanic disaster. This story’s sequel is the history of radio, in which David Sarnoff—an uneducated immigrant boy who admired Marconi and who started his career doing menial work at the American Marconi Company—eventually became the emperor of broadcasting at RCA. Many of us (at least, many of us born before the advent of personal com- puters) had the experience of fabricating a radio from a kit consisting of a coil, wires, a tiny crystal, and an earphone. Some may remember the feel- ing of wonder when radio signals were first captured by such a primitive receiver. Similar feelings were experienced by the wireless pioneers. For example, in 1934, John Ambrose Fleming, the inventor of the thermionic valve (i.e., the diode vacuum tube), still remembered how surprised he had been in 1898 when he had seen a Morse printer printing a message from Marconi (Fleming 1934, p. 116). The early development of wireless communications has been described in detail by Hugh Aitken, but even he did not attempt to probe the substance and context of scientific and engineering practice in the early years of wire- less. In this book I attempt to fill that gap. My main goal is to provide a detailed analysis of engineering and scientific practices that are not only experimental but also theoretical. Examples include the engineering prac- tices involved in Marconi’s earliest wireless telegraphy, Fleming’s “grafting” of power technology onto wireless telegraphy, Marconi’s innovation in tuning as represented in his “four-seven” patent, Fleming’s research on the unilateral conductivity in the Edison effect, and Lee de Forest’s invention of Preface xi the triode. I also aim to explore the borderland between science and tech- nology. For that purpose I pay close attention to the work of Fleming, who was trained in experimental physics by Maxwell but who moved to wire- less telegraphy when he became Marconi’s scientific advisor. One impor- tant mode of such “mediation” is the transformation of scientific effects into technological artifacts. I discuss several notable cases of this process, including the transformation of Hertzian waves into practical wireless teleg- raphy, Marconi’s transformation of a resonance principle into a stable arti- fact, Fleming’s utilization of the unilateral conductivity for the valve, and the transformation of “negative resistance” into the transmitter of contin- uous waves. Taken together, my accounts of these engineering practices pro- vide a window on or a context for such novel practices. (By context I mean techno-scientific, corporate, or authorial settings that promoted or con- strained inventions and innovations.) My analyses of the Maskelyne affair, of tuning technology, and of the invention of the valve in the context of cor- porate politics exemplify my efforts to link engineering practices with spe- cific contexts. The construction of these contexts is based largely on archival sources previously overlooked or underused by historians. In chapter 1, I discuss the origins of wireless telegraphy by contrasting physicists’ Hertzian optics with Marconi’s telegraphic imperatives. I classify the scientists and engineers who claimed to have devised wireless telegraphy before Marconi into three categories: (1) British Maxwellian physicists and engineers, including John Perry, George FitzGerald, Frederick Trouton, Alexander Trotter, and Richard Threlfall, who suggested a practical use of Hertzian waves for communication in the early 1890s, (2) William Crookes, who provided a detailed description of wireless telegraphy in 1892, and (3) Ernest Rutherford and Captain Henry Jackson, who actually performed experiments for communication with Hertzian waves. I show that all this work was constrained by optical analogies of electromagnetic waves. These researchers had access to a complex web of conceptual and instrumental resources associated with Hertzian optics; however, these optical resources, which opened a new arena of physical research and even opened new tech- nological possibilities, also conditioned and constrained the transformation of Hertzian apparatuses into practical wireless telegraphy. Re-evaluating Marconi’s ingenuity in a more historical and contextual manner, I discuss how Marconi’s ingenuity and originality sprang from his devotion to perfecting the homology between wired and wireless telegraphy. xii Preface In chapter 2, I take up the priority dispute between Marconi and Oliver Lodge, who (it has been claimed) demonstrated wireless transmission of alphabetic messages in 1894. I show that Lodge’s putative demonstration of wireless telegraphy in 1894 had nothing to do with telegraphy, alpha- betic signals, or dots
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