Time Standards for the Twentieth Century: Telecommunication, Physics, and the Quartz Clock
2017; University of Chicago Press; Volume: 89; Issue: 1 Linguagem: Inglês
10.1086/690282
ISSN1537-5358
Autores Tópico(s)Australian Indigenous Culture and History
ResumoPrevious articleNext article FreeTime Standards for the Twentieth Century: Telecommunication, Physics, and the Quartz Clock*Shaul KatzirShaul KatzirTel Aviv University Search for more articles by this author PDFPDF PLUSFull Text Add to favoritesDownload CitationTrack CitationsPermissionsReprints Share onFacebookTwitterLinked InRedditEmailQR Code SectionsMoreScene 1: a full-screen clock, its second hand approaching six o’clock. Dozens of workers rush through the street and into the factory, punch their timecards, and hurry to take their places near the huge machines. Scene 3: the assembly line is set at its maximal speed and the Little Tramp struggles to match the pace of the machine; alas, he fails and is swallowed helplessly between the cogs of the machine.In these forceful images from Modern Times, Charlie Chaplin conveyed the tyranny of the clock in the modern mechanical world. According to this common image, clocks and machines in the hands of the powerful actively imposed time discipline and the breakneck speed of modernity on the reluctant population. Submission to time discipline, however, was a more complex and fascinating process, as it grew out of the interactions of state agencies, corporations, and individuals with an array of changes in modes of transportation and telecommunication. In 1936, when Chaplin made the film, industry had already begun its transition from the mechanical to the electrical and electronic world of smaller machines on the shop floor and smaller appliances and radios in the home. Not that time and speed became less important—on the contrary, their importance only became more pronounced. Scientists, engineers, and technicians invested countless hours in devising new clocks and synchronization devices for the needs of these novel technological systems. The most famous result of their work was the quartz clock. Invented almost a decade before Modern Times was released, it was the first chronometer to exceed the accuracy of the mechanical pendulum clock, which had served as the standard since the seventeenth century. With its invisible electromechanical vibration, its often hidden existence in virtually any smart electronic gadget, and its almost inescapable presence, the quartz clock disseminated time discipline in a subtler and more comprehensive way than ever before.As depicted by Chaplin, the mechanization of production required synchronizing the actions of workers in one location, namely, the factory. But the new technological systems such as telephony and radio that characterized the twentieth century required synchronization across vast spaces and political boundaries. Synchronization, in turn, demanded and led to both the widespread availability of accurate time signals and a stronger time consciousness throughout the population. The clock became central to an increasing number of activities, not only in the workplace but also, more significantly, in the home, for such family and leisure activities as listening to or watching broadcasts. Those involved in such activities consequently adopted the concept and discipline of time as marked by the clock. This was not a new development, but it expanded in the twentieth century to encompass a much broader population. Such an expansion could not have taken place without the ubiquity of time signals made available through watches, domestic and public clocks, and time announcements on radio and television, and without the many activities cued by time signals. Historically, it was only the technology of quartz crystal time and frequency measurement, culminating in and symbolized by the quartz clock, that enabled the unprecedented availability of exact time signals and the extensive synchronization and scheduling of daily activities. The result was a time discipline that was on the one hand more subtle, as it was established without explicit compulsion, but on the other hand more powerful, as it had a stronger hold on many more realms of life involving a far greater number of inhabitants of the modern world.Historians have long recognized that changing concepts of time and of the lives of people vis-à-vis time are central for our understanding of the origins of the modern Western world. Depending on their expertise and understanding of the changing historical roles of the clock, they have concentrated on different epochs, places, and groups, from the origin of the mechanical clock in the European Middle Ages through its evolution in early modern Europe and into the nineteenth century.1 Both late medieval monasteries and emerging towns have been cited as originating and disseminating the mechanical clock and its usage, leading to a novel conception of time. In an influential article, E. P. Thompson identified the emergence of a stricter and more comprehensive time discipline around the first half of the nineteenth century, which he attributed to British industrial capitalism and its “puritan ethos.”2 Other historians have pointed out the roles played by astronomers, the bourgeoisie, commerce and technology, and, in particular, transportation and communication in fostering a growing time awareness and a need for coordinated clocks at different locations.3 The next step in strengthening the power of the clock in daily life during the twentieth century, however, has not received similarly detailed attention.4This article examines the origins and development of highly accurate quartz-clock technologies and the social, technological, and scientific forces that shaped them.5 To a considerable degree, the pursuit of accurate time determination and dissemination grew out of the characteristic developments of the twentieth century—the emergence of processes, forces, and organizations that either had not existed or had been considerably weaker in the past. In particular, the quartz clock originated in the formative event of the short twentieth century: the First World War. Further, the technology was shaped and advanced by perhaps the two most central organizational structures of the century: the state and large corporations. Its early history shows both their collaboration and their rivalry: with the development of the quartz clock, a commercial company for the first time successfully employed its own monopolistic economic power to undermine the state’s monopoly on standards.6The role of these organizations notwithstanding, in practice the clock was based on and developed through scientific and engineering research, an acknowledged but still underestimated force in shaping the modern world. While relativity and quantum physics attracted popular and historical attention, research in more “mundane” fields of physics such as electricity in crystals and gases provided knowledge crucial for developing the quartz clock. At the beginning of the century, states and corporations started to appreciate that scientific and technological research could sustain and even increase their economic and military power, and they established new kinds of research laboratories that combined scientific and technological research aimed at meeting their needs. Anticipating developments in radio technologies and the feasibility of contriving improved measuring techniques, two of these laboratories played a central role in developing the quartz clock.7By allowing the widespread use of accurate measurement and control in telecommunication, the quartz clock enabled the construction of large centralized systems. Such centrally controlled systems enabled large corporations to dominate their technological fields and to advance a hierarchical view of society at large that was “at odds with America’s original democracy.” Modern engineers, David Noble has claimed, were “agents of corporate capital.” Yet this article shows that some researchers outside corporate laboratories tried to weaken the hold of centralized power and sought to allow individuals and small organizations independent access to the new measurement technology, thus strengthening the position of those smaller entities within the emerging state-regulated networks. These researchers manifested a democratic tendency to disseminate technological methods to a relatively large number of users, running counter to the centralized authoritative tendencies of the corporations that wished to control usage of the techniques they developed.8 As this article will show, the intrinsic scientific and technological properties of the systems themselves tilted the balance toward an open, accessible technology, despite the strong economic power of the corporations.This was not the only case in which the inherent properties of devices and systems and the scientific and technological knowledge about them constrained technological development and shaped the outcome of the historical process. To understand the emergence of particular technologies and their influence on society, we must explore not only the social and economic interests and consequent needs of different users of those technologies but also the material constraints and internal dynamics of the technologies themselves. The present article thus examines the technological developments that led to the quartz clock in a multiplicity of contexts, including their grounding in science, technology, and preexisting practical methods as well as their evolution in response to the economic, social, and military needs of telecommunication users.The quartz-clock technologies and the demand for a higher level of synchronization had roots in earlier networks whose coordination required agreement in time measurements. Railway networks, scientific interests, telegraphy, and radio led to high accuracy and standardization in time measurements, which provided the conceptual, technical, and legal framework within which later quartz technologies would develop (Sec. II). New electronic methods for measuring frequency and time originated in research on wireless communication for World War I military uses. These methods were further developed by the British National Physical Laboratory (NPL) and the American Telephone and Telegraph Company (AT&T)9 in establishing standards for frequency measurement.10 The NPL needed frequency standards in order to regulate the national and imperial radio network, as did AT&T to integrate its telecommunication system (Sec. III). An expansion of the range of frequencies used for telecommunication, a need to limit transmissions to particular values, and the aim of allowing multiple telephone calls on the same wire led AT&T to develop novel methods of crystal frequency control for their standard of frequency and time, resulting in the first quartz clock. A scientific ethos of exactitude stimulated further refinements in the clock’s accuracy (Sec. IV). National laboratories developed similar crystal control methods for their own frequency standards and for international comparison and collaboration, as did independent researchers seeking to provide small users flexible control over the frequency of radio transmitters. Both research projects resulted in alternative techniques for constructing quartz clocks (Sec. V). These developments allowed the spread of quartz time technologies, which, as I will argue in Section I, strengthened the grip of objective time and of the clock on modern life. Understanding the origins of these technologies will therefore help us understand the forces that strengthened the role of time and of synchronization in the twentieth century.I. The Quartz Clock and Stronger Time DisciplineThe early twentieth-century Western population showed an increasing awareness of precise time and the need for agreement among different clocks. Uniform clock time became more important as a result of the expanding role of the clock in transportation and the workplace, enabled by the development of timekeeping technologies that allowed for synchronized clock systems and cheaper domestic clocks.11 Still, the newer technologies of quartz time and frequency measurement constituted a further step in the spread and adoption of time discipline. In particular, these technologies enabled the penetration of time awareness into private and leisure activities, hitherto quite resistant to the rule of the clock. The new technologies strengthened the role of time in society in two ways. First, they led to a dramatic increase in the number and the accuracy of clocks, watches, and other time announcements available to the general population. Second, they allowed an expansion of the number and kinds of actions scheduled by external “mechanical” timekeepers.Although by 1920 the best pendulum clocks erred by less than 0.01 seconds a day—a level of accuracy far greater than that required for daily needs—the time shown to the public was often surprisingly inaccurate. In 1921 a New York journalist observed that “to obtain accurate time is far from easy in great cities. Naval Observatory service from Washington [providing highly precise time] is distributed to a very small part of the population. The public sets its watches by tower clocks, jewelers’ chronometers, factory whistles and fire bells, which may vary as much as five minutes.” This was still better than “the time as it [was] known to the average New Yorker.” “Selecting a typical street [an “electrical man”] walked up one side [of] several blocks and down the other, noting the time displayed on outside clocks maintained by merchants for pedestrians’ convenience, inside clocks visible from the street, and jewelers’ clocks and chronometers in windows—all of which were running merrily and being taken as a standard by somebody, although they were as much as forty minutes apart!”12 The situation was probably better in a few large metropolises in western Europe, such as Berlin and London, where some public clocks were synchronized by special systems constructed for that purpose. Still, most Western urban populations (not to mention the rural ones) had no daily access to clocks more accurate than those of New York. Within a few years, however, the emergence of broadcasting would dramatically change the situation. The radio informed listeners about the exact hour many times a day—by frequently announcing the time, by introducing “pips” signals before specific hours, and by scheduling programs at a known regular hour.13 This allowed individuals to adjust their clocks and watches frequently so that they could keep them accurate enough for their needs. Unlike earlier time-distribution systems, radio did not require advance registration, payment, or special equipment and skills.14 Hence it spread time announcement to a much broader population than earlier technologies had done. Among other factors, the expansion of broadcasting depended on the quartz-clock technologies of frequency and time measurement. Indeed, as we will see, the quartz clock was invented for and served the needs of electric telecommunication, thereby allowing the distribution of time through electromagnetic waves.With miniaturization, quartz clocks and watches became inexpensive and thus widely accessible, providing virtually ubiquitous, highly accurate timekeepers for domestic and personal use. By 1913, watches had already become a mass commodity with a world annual output of about 30 million units—a large number for the time, but still very limited in comparison to the more than 1 billion watches exported from China alone in 2012,15 and even more limited in comparison to the total production of quartz timekeepers, only a small portion of which are watches. Quartz clock technology is used not only in domestic, office, and public clocks and watches but also in many electronic gadgets, including every computer and each of the 1.7 billion mobile phones sold in 2012, reaching almost every room and every desk in the world. These ubiquitous timekeepers offer accuracy previously limited to special scientific uses. Common quartz watches were about one hundred times more accurate than their mechanical predecessors. Inexpensive mechanical watches that erred by one to two minutes a day sold in the millions at the middle of the twentieth century, while considerably cheaper quartz watches kept time within one second a day and spared the need for daily maintenance.16 Quartz clock technologies thus allowed the spread of exact timekeepers to virtually every corner of the world, raising awareness of the exact time and strengthening its role in everyday life.Quartz-clock technologies not only enabled widespread knowledge of the time but also created a need to act according to the exact objective time. They did so especially through radio and television broadcasting, scheduled according to a central quartz clock and transmitted with the help of quartz-clock technology. Catching trains, which departed at fixed times, raised time consciousness in the nineteenth century—yet a train trip was still a rare event for most people, and even daily commuters did not need to worry about the exact time after they returned home. This situation was changed by radio. Unlike taking a train trip, listening to the radio was a daily activity common to a large urban and rural population. Turning on the radio in time to listen to one’s favorite program required knowledge and awareness of the time. This was true when the same show was always scheduled at the same hour and also when sequels were broadcast at different hours and days of the week. In the first case, people often adopted a routine organized by the central clock; in the second, they needed to be alert to the exact time of the transmission at different hours of the day. Listeners’ “home lives were placed on strict timetables to fit in with their favourite shows … their family life, particularly in the evenings, was organized according to these requirements.”17Moreover, from the late eighteenth century and into the nineteenth, awareness of the exact time became important for commerce, transportation, and labor. Stricter requirements for working according to the clock in the factory and at schools contributed to the spread of a time discipline that also aroused antagonism.18 Listening to the radio, in contrast, was usually a leisure-time activity carried out within the family’s private sphere at hours when they had not previously cared much about the exact time. In the past, the rule of the clock at home had usually been connected to external obligations. From Kafka to Ken Loach, the alarm clock became a popular symbol for the way social organizations such as the workplace imposed their discipline on the population. No similar compulsion was felt regarding radio. Listeners chose to arrive home or to turn on their radios at a certain time to listen to a particular program. With the voluntary embrace of radio within the domestic sphere, acceptance and adoption of the time discipline suggested by a broadcasting schedule became widespread.19II. Unification and Standardization of Time before World War IAt the beginning of the nineteenth century, time was a local matter, defined by the position of the stars as observed at a specific place. In 1830, for example, when trains connected Manchester to Liverpool, time in the port city lagged that of its eastern neighbor by about three minutes. Noon was defined by the transition of the sun at its highest point in sky, but due to the daily rotation of the spherical earth, the sun reaches that position first in Manchester and three minutes later in Liverpool. By the end of the century, a national synchronization network ensured that clocks in the two cities would show the same legal time, which was valid in the whole of Great Britain. Moreover, this legally binding standard, known as Greenwich time, was also a reference for an international system of time reckoning. The extension of railway networks was the central force behind the transformation of time designations from local to regional and later national and international values.A railway network required that train traffic be coordinated to enable its flow and to prevent collisions. Knowledge of the time in the various cities in the network and in the trains that departed from those cities was necessary for this end. Different cities could keep different times, but the system required that all these different clocks be synchronized, in the sense that they had to run at the same pace and thus keep constant known differences. The interdependence of train companies, stations, and users made uniform time—that is, one time shared within a large zone—a preferable way of coordinating the railway system.20 In retrospect, the process stimulated by the trains can be seen as one major stage in tightening time coordination across space, a process that advanced another step following the stronger interdependence of electrical communication from the 1910s.Notwithstanding the role of transportation, scientific interests and the technological characteristics of the clock also contributed to the standardization and unification of time. The time used by train companies and hence by their users was not the one directly observed by a sundial but a “mechanical time” defined and monitored by astronomers. For their observations, astronomers needed an accuracy and regularity greater than that required by civil life. As the motion of the earth around the sun was known to be nonuniform, astronomers devised a theoretical scheme to calculate the exact time from sidereal observations, producing equal hours, minutes, and seconds along the year. These uniform seconds were manifested in accurate pendulum clocks monitored by astronomical observations. The same kind of uniform time, if not one of similar accuracy, characterized mechanical clocks in general and was adopted by a large segment of society, especially among the bourgeoisie.21Systems of precise time coordination emerged from a combination of national, scientific, and commercial needs and were enabled by technologies of timekeeping and electric communication. The telegraph network provided a means to distribute time signals from astronomical clocks and to synchronize wide areas. In the early 1850s, George Airy, the British royal astronomer, initiated a system of transmitting the time from the Greenwich observatory “directly to the main centres of government and commerce as well as through the country generally.” By connecting Greenwich time to the centers of government, Airy and the British officials who sanctioned his move made it the state time (even if not by legislation). Since the observatory itself was a state institute, as most major observatories were, time determination and its distribution became a concern of the state. The state thus became the authority on time and assumed the responsibility of providing exact knowledge of that time to its citizens. Joseph Conrad captured the role of the observatory in his 1907 novel The Secret Agent, in which the Greenwich observatory became a target for an anarchistic bombing directed at a symbol of science and the centralized power of the state. Counterpart observatories in Europe played similar roles in their states. The case was somewhat different in the United States, where university and private observatories provided exact time signals; nonetheless, the most authoritative time signal originated in the astronomical clock of the US Naval Observatory.22In addition to their needs for scrutinizing the sky, observatories needed to know time differences between distant locations in order to determine longitudes—the exact east to west angular distance between places. Exact clocks in both locations and telegraph transmissions assisted in this mission. In 1908 the French suggested addressing the same problem by using the new radio technology to send time signals, accurate to within 1/100 of a second, from the central state observatories. Once broadcast, the new state-approved time signals were received and used by many patrons. Still, until 1922, when time began to be announced in regular broadcasts, these signals were received and interpreted only by special users with an interest in highly precise time measurement and were inaccessible to the general public.23The use of radio waves to send time signals across political borders marked a shift from national to international authority and responsibility for time determination. A discrepancy between the clocks at French and German observatories was one reason for summoning an international conference on time measurement in 1912. The conference decided on the creation of an independent international bureau for the task, similar to the one for weights and measures. This plan did not materialize, but a Union internationale de radiotélégraphie scientifique (URSI) that depended on the various national organizations was eventually established after the First World War. At its second meeting in 1927, two researchers from AT&T, J. W. Horton and Warren Marrison, announced the construction of the first quartz clock.This connection between radio and time standard was neither accidental nor totally new. Robert Goldschmidt, a Belgian scientist and radio entrepreneur, had initiated the establishment of the URSI during the 1912 conference on time measurements. After the war this private initiative was incorporated as a suborganization of the novel international research council. It was a nongovernmental association that was still organized by national committees. Many of the URSI members worked within state organizations; others worked for telecommunication companies such as AT&T.24 After the war, both commercial companies and state agencies showed a strong interest in precisely determining radio frequencies—that is, the number of oscillations per second of the radio (electromagnetic) wave. As a measure of cycles per second, frequency is closely linked to time. Its accurate measurement thus required a precise time determination. Since the growing demands of radio, or wireless, communication required high precision in frequency measurement and coordination, it also demanded accurate time measurement. Arguably, radio was the most rapidly expanding and exciting technology of the 1910s and 1920s, attracting numerous researchers and significant investments.25 One of the fields studied, frequency measurement, resulted in new technologies based on quartz crystals and tuning forks to measure both frequency and time. Electric communication required much higher accuracy than that needed for the railway network, and it presented new challenges to researchers.III. Tuning-Fork StandardsHorton and Marrison’s quartz clock originated in First World War research on accurate means to measure frequencies, carried out mostly by civilian scientists who joined the effort to improve wireless communication following their mobilization for war research. In their work for French military radio telegraphy, the physicists Henri Abraham and Eugène Bloch devised a new method for measuring high radio frequencies (tens of thousands of cycles per second, or Hertz) with the help of the tuning fork, a device long used by acousticians to determine sound frequencies. Exact knowledge of frequencies was necessary for Abraham and Bloch’s project of improving the novel amplifier that had come into use: the triode, an electronic vacuum tube with three electrodes (fig. 1) that was the central device beyond contemporary radio and electronics in general before the advent of the transistor in the 1950s. Resembling an incandescent lamp, the glass surface of an electronic vacuum tube encloses a space of low-density air (“vacuum”) and two or more electrodes (three in the case of a triode), allowing an electric current (“discharge”) under specific conditions. Abraham and Bloch utilized the triode in a new device, which they termed a “multivibrator,” to multiply the frequency of the tuning fork to reach radio frequencies. Their method enabled comparing the radio oscillations with the vibrations of the tuning fork and then to the period of an astronomical clock that served as a highly accurate time standard. Abraham and Bloch devised this method for the immediate needs of their research on improving the triode for war radio communication, but its high accuracy stemmed from their own scientific attitude as well as from a nineteenth-century scientific tradition of exactitude in using the tuning fork.26Fig. 1. A triode (an electronic vacuum tube with three electrodes), Western Electric (the manufacturing arm of AT&T) 101F, about 11 cm high. Picture from stonevintageradio.com.View Large ImageDownload PowerPointAbraham and Bloch further devised a triode circuit that could oscillate at the steady frequency of a tuning fork incorporated in that circuit. Although accuracy was one of their broad concerns, their initial aim in designing this apparatus was to amplify currents at low known frequencies for use in the military wireless. A similar goal of measuring amplification power had motivated William Eccles, an engineering professor and radio expert, in his war research in England. Unlike his French colleagues, however, Eccles had already considered the combination of tuning forks and triodes for radio before the war for commercial reasons. He had tried, albeit unsuccessfully, to circumvent a patent of the German company Telefunken.27Indeed, even before the war, telecommunication had already entered a period of massive changes because of the development of the new vacuum tubes. Since John Fleming’s 1904 invention of the electronic valve, many inventors had improved and modified the device for multiple uses in radio: as a current rectifier, an amplifier, a sender, and a receiver. Invented by the independent scientist Lee de Forest, the triode and methods for its use were extensively developed by the research laboratory at AT&T for application in telephony. Physicists at the laboratory exploited f
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