Communication
Telegraphy
The word telegraph comes from the French télégraphe, meaning “far writer,” a term coined by Claude Chappe (1763-1805 AD) for the invention of a system to transmit messages or information to a distant locale. French Emperor Napoleon was a believer in the technology that allowed him to monitor his expanding empire in the eighteenth century.Samuel Finley Breese Morse (1791-1872), the American painter-become-inventor, was a master of assembly. He envisioned both a simple telegraph design coupled with a binary coding system of dots and dashes; these Morse code designs became world-wide standards. Morse listened, learned, and then proceeded to sort out and simplify telegraphy for almost any operator. He overcame the complexity of Englishman Wheatstone’s message board and the isolation of Siemens’s needle system in the German states, and dominated the marketplace. Morse built upon Joseph Henry’s electromagnets, Wheatstone’s telegraph pole and relay, Carl Steinheil’s earth return implementation, William Grove’s sealed and improved wet cell battery, and the talents of two colleagues—Alfred Vail who built the telegraph key and sounder, and Professor Leonard Gale who provided scientific knowledge.
Morse advanced the telegraph's system of encoding and decoding messages over long distances in the 1830s, building on the use of electrical impulses sent over iron wires to transmit messages. In 1842, Morse demonstrated the telegraph between two committee rooms in the U.S. Capitol. With intensive lobbying, Congress passed a $30,000 appropriations bill in 1843 to build the first telegraph line from Baltimore to Washington, a distance of thirty-seven miles. Morse was named superintendent of telegraphs and was responsible for overseeing its construction. Completed in 1844, Morse invited prominent people to the May 24 formal opening. The first message sent was the biblical quotation “What Hath God Wrought!” After this, acceptance was rapid as thousands of miles of telegraph cable were strung along railway lines all across North America. The word “telegram” entered the lexicon in 1852 and over two hundred million telegraph messages were sent annually at the height of its popularity.
Telegraph lines were placed along planned railway right of ways, even as the new tracks were being laid. This urgency was heightened by the value of dispatching trains using the telegraph. Efficient, instantaneous communications enabled by telegraphic dispatching easily quadrupled the traffic-carrying capacity of the single-track railroad. Trains could be sent on their way by telegram, even before others arrived. Businesses recognized the productivity gains telegrams afforded in sending money orders, contracts for review, and newspaper stories filed by field reporters, to name a few.
From the ideas of the 1830s to wide scale global deployment in the 1850s, the growth of electric telegraphy was explosive. By 1852, the amount of telegraph wire exceeded a thousand miles in many countries. The next two decades saw the global mileage of telegraph wire swell to 650,000 miles. The innovation of using gutta percha [a rubber-like gum produced from the latex of various South East Asian trees] to prevent water damage to telegraph wires, first used by the Siemens and Halske Company, saw the proliferation of underwater cables, with 30,000 miles of telegraph wire put in place. The first submarine cable linked Dover, England and Calais, France, in 1850, laid by the Siemens’s company. The telegraph began humanity’s quest for global connectedness, at least on the physical level, through the medium of wire and the movement of electrons. The 1870s found 20,000 towns and villages around the world able to send and receive telegrams. By 1856, 35,000 miles of telegraph line in the U.S. delivered over seventeen million messages, generating seven million dollars in revenue for American telegraph companies.
Christopher Sholes (1819-1890) was spurred to develop a typewriter in 1867 for use by telegraph operators. Typewriters increased the speed and accuracy of message reproduction. Productivity gains achieved by the typewriter led operators to use a common set of abbreviations. Using this Phillips Code, top-notch operators dealt with 20,000 words per shift. Electronic shorthand such as 'Scotus' for 'Supreme Court of the United States', developed in the 1870s is reminiscent of today’s Internet shorthand used in instant messaging such as 'LOL' for 'Laughing Out Loud,' which started in the 1990s. The need for secrecy for many transmitted messages demanded both the senders and receivers adopt codes. For example, classified material sent among the various atomic bomb development sites working on the Manhattan Project in the early 1940s employed code words and phrases. The technical term ‘isotope of uranium’ became ‘igloo of urchin’ when used in a message sent across the telegraph network.
Wherever telegraph offices were established along American railway lines tremendous social and economic benefits emerged. Telegraph technology was instrumental in standardizing time zones across the breadth of North America, critical for revolutionizing how trains were dispatched, and for enabling instant transmission of news and stock market activity. The telegram found people at home, at work, and aboard railway trains. Its ability to speed communications drove people’s actions—this in itself was revolutionary. Just like the revolution of the printing press, which delivered books for the reflection of ideas and subsequent implementation, telegraphy used the speed of light to send telegrams for instant absorption and immediate action.
The rise of telegraphy at the dawn of electric communication and the rapidly evolving science of electricity triggered what many call the Second Industrial Revolution. During this period, from 1870 to 1930, the electric telegraph played a defining role. In fact, Morse’s telegraph system transformed journalism, transportation, industry, government and military operations, and the very pace of daily life. The telegraph system was the defining step in ushering in the communications explosion of the twentieth century.
Telegraphy became big business and invaded all walks of life. It reigned for more than 150 years, but eventually all good things must come to an end. The last telegram was sent by Western Union on January 27, 2006, its technology replaced by fax machines using telephone lines, e-mail over the computer-driven internet, and text messaging leveraging new wireless networks.
James Clerk Maxwell's Poem About Telegraphy
James Clerk Maxwell (1831 – 1879), besides developing the theory of electromagnetic wave propagation, also dabbled in poetry. He was inspired with the practical work on telegraphy conducted by William Thomson or Lord Kelvin (1824 – 1907) in the late nineteenth century.
Maxwell wrote
VALENTINE BY A TELEGRAPH CLERK TO A TELEGRAPH CLERK
The tendrils of my soul are twined
With thine, though many a mile apart,
And thine is close-coiled circuits wind
Around the needle of my heart.
Constant as Daniell, strong as Grove.
Ebullient through its depths like Smee,
My heart pours forth its tide of love,
And all its circuits close in thee.
O tell me, when along the line
From my full heart the message flows,
What currents are induced in thine?
One click from there will end my woes.
Through many an Ohm the Weber flew,
And clicked this answer back to me, –
I am thy Farad, staunch and true,
Charged to a Volt with love for thee.
Electronics - Enabled by the Vacuum Tube
Vacuum Tubes the impetus for the electronics revolution of the twentieth centuryOne of the greatest developments in electronics was the invention of the vacuum tube. Its beginnings can be traced to the advances made in efficient vacuum pumps, advanced glassblowing techniques, and induction coils. Early versions of vacuum tubes appeared in the late seventeenth century with experimenters such as Francis Hauksbee. However, it was not until the mid-nineteenth century that the technology was adequate enough to produce reliable vacuum tubes.
A vacuum tube consists of two or more electrodes enclosed in a glass sleeve that has been evacuated. As electric current is applied, heat from the filament enables electrons to boil off of the cathode. A positive plate voltage attracts these electrons, producing a flow of current. A small negative bias voltage applied to a third electrode, the grid, prevents some of the electrons from reaching the plate, thus reducing current flow. Small amounts of applied grid voltage have a large effect on the plate voltage. In making the vacuum tube so adjustable it could function as an amplifying device. The year was 1907 when Lee De Forest created the triode. He called his amplifying vacuum tube the Audion. Incorporated into Marconi's wireless system, communications could take place over much greater distances. Leveraged as a telephone signal amplifier, American Telephone and Telegraph Company (AT&T) made long-distance telephone communication practical. In generating radio frequency signals, broadcasting was made possible with the inauguration of the first radio news broadcast in 1916. Such accomplishments earned de Forest the title of Father of Radio in the United States.
Triodes found a home in the development of television receivers where a myriad of signals required amplification. Another significant contribution came from Philo T. Farnsworth in 1927. He originally designed the ‘shielded grid tube’ or tetrode with an extra grid to isolate the plates to give better gain and frequency response for the rigorous demands of television. This was part of the overall system of television he invented, from the camera (Image Dissector) to the broadcast transmission scheme, and the electronic receiver. Farnsworth is aptly named the Father of Television.
The vacuum tube in its various forms persisted as the dominant force in the progression of electronics technology, overseeing the introduction of AM and FM radio, television, radar, and computers. The invention of the transistor in 1949 heralded an end to the reign of the vacuum tube.
Even while solid-state transistors and semiconductor technologies were replacing tubes in consumer electronics for their smaller size and lower current consumption, vacuum tubes found new applications. In industry, high-power tubes are used in welders and gluing machines. Another very important tube, used in oscilloscopes to display waveforms, is the Cathode Ray Tube (CRT). Its popularity for seventy-five years has made it a workhorse in many consumer products such as the picture tube used in televisions and monitors. Microwave ovens use a vacuum tube called the magnetron. The food to be cooked is placed in the ‘oven,’ a microwave cavity. The magnetron generates the microwave energy to vibrate the food’s water molecules and heat it. The harnessing of the electron through the use of vacuum tube technology started the electronics revolution of the twentieth century.
References:
Koslowsky, R. K. A World Perspective through 21st Century Eyes – The Impact of Science on Society. Victoria: Trafford Publishing, 2004.
Lewis, Tom. Empire of the Air, The Men Who Made Radio. New York: Edward Burlingame Books, 1991.
Schwartz, Evan I. The Last Lone Inventor: A Tale of Genius, Deceit, & the Birth of Television. New York: HarperCollins, 2002.
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