In the early years of the twentieth century Nova Scotia played an important role in the history of communications by becoming the North American terminus of the first transatlantic radio communications service. Not only did this service link the Old World and New World by the magic of radio, but it was the first link in the worldwide wireless network that we take for granted today. The driving force behind this accomplishment was a young Italian, Guglielmo Marconi. In the course of establishing the transatlantic service, Marconi built three large radio stations in Cape Breton: the first in Glace Bay, the second just south of Glace Bay, and the third in Louisbourg. The story of these stations is the subject of this article.
Let us first define what is meant by "radio" in the context of this article. Radio is a system of wireless communications that utilizes radio waves. Radio waves are invisible electrical waves that travel through space at the speed of light. This speed enables them to traverse the distance between any two points on the globe in a fraction of a second. Radio encompasses both point-to-point communications and broadcasting, but the former was the principle application during the first twenty years or more that are the subject of this article.
As radio evolved, so did its terminology. "Radio" and "wireless" initially were prefixes; e.g., radio or wireless telegraphy or telephony. When broadcasting became popular in the 1920's, both words came into general use to describe the whole field of radio broadcasting and communications. The term "radio" became more popular in Canada and the United States, and "wireless" became more popular in Great Britain. In this article, these words will be treated as synonymous, and usually will refer to radio or wireless telegraphy.
The first practical system of electrical communications was the telegraph, which came into widespread use in the 1840s. In this system, messages were transmitted along wires from the sending station to the receiving station, usually as a sequence of short and long electrical impulses ("dots" and "dashes") that comprised the Morse Code. Soon after its invention, submarine telegraph cables were laid across the bottoms of bodies of water, and the first commercially successful transatlantic cable was laid in 1866. By the end of the century, when radio was ready to span the Atlantic, there were a dozen or more transatlantic cables. The telephone, which transmits electrical voice signals over wires, was invented in 1876. However, at the end of century, long distance telephony was still in its infancy, and transatlantic telephone cables were more than fifty years in the future.
Wireless communications were attempted as early as the 1860's by Mahlon Loomis in the United States, but a clear understanding of the basic principles of radio only emerged after the theoretical work of the Scottish physicist James Clerk Maxwell in the 1860's and the experimental work of the German physicist Heinrich Hertz in the 1880's. Guglielmo Marconi read about Hertz's work in 1894 when he was just twenty years old. He realized that radio waves, then called Hertzian waves, might be utilized for wireless communications, an inspiration that set the course of his life's work. His first step was to set up a laboratory in the attic of the family villa near Bologna, Italy, and repeat some of Hertz's experiments. His next objective was to increase the distance over which radio waves could be transmitted and received far beyond the confines of a laboratory. Before the end of 1895 he transmitted wireless signals a distance of over a mile, an event that many consider to be the birth of radio. Consequently 1995 was celebrated around the world as the centennial of radio. These celebrations included a visit by the Italian naval ship Zeffiro to Atlantic ports, including Halifax, Sydney, St. John's and some American ports, carrying an exhibit of early Marconi radio apparatus and photographs.
Radio waves are generated by alternating or pulsating currents of high frequency (many vibrations per second) flowing in a radiating structure called a transmitting antenna. Hertz generated these currents with the aid of a high voltage electric spark, and Marconi followed his lead. To transmit radio waves over large distances, Marconi replaced the small antenna used by Hertz with a high aerial wire supported by a tall wooden pole.
At the receiver the process was reversed. A high aerial wire intercepted the radio waves and converted them back into electrical signals. These, in turn, were rendered audible or visible by a sensitive device (or class of devices) called a "detector". If the signals were weak, they might be heard with a pair of headphones or earphones, an adaptation of the telephone receiver, and if the signals were strong, they could be recorded on paper tape. Messages were transmitted in Morse Code by switching the transmitter on and off with a telegraph key. This was the Marconi system of wireless telegraphy, and it remained the principal system of radio communications until about the beginning of World War One in 1914.
The Italian government showed little interest in Marconi's demonstrations of his early apparatus, so he and his Irish mother took it to England in 1896. There her prominent family was able to introduce Marconi to influential people. He received a warm reception and assistance from the British Post Office, and England became the headquarters of his future radio empire. With the aid of his mother's family and financial backers, Marconi formed the Wireless Telegraph and Signal Company in 1897 to manufacture and sell or lease radio equipment. The marine industry was his principal market because the British Post Office had a monopoly on overland communications, and because, then as now, radio offered the only practical means of communication for ships at sea. Radio installations provided ship-to-ship and ship-to-shore communications, and radio operators were known as "Sparks" because of the mysterious and intimidating spark transmitters they used.
By the end of the century, Marconi's dreams extended beyond marine radio. He wanted to create a worldwide radio communications network consisting of powerful land-based radio stations. The first step would be to bridge the Atlantic ocean and connect the New World with the Old World by wireless. Most scientists of the day thought that this was impossible because radio waves, like light, should be limited to approximately line-of-sight distances. However, Marconi had evidence that this limit had already been exceeded, so he pragmatically continued to seek greater ranges by building bigger and more powerful stations. What no one knew at the time was that the ionosphere, a layer high in the atmosphere that reflects radio waves, would make Marconi's dream possible.
By 1901 Marconi and his company were ready for the transatlantic radio
experiment. The plan was to use his high powered stations at Poldhu, in
Cornwall, England, and at Cape Cod, Massachusetts, U.S.A., but
unfortunately the antennas at both stations were blown down by gales in
the fall of 1901. A temporary transmitting antenna was then constructed
at Poldhu, and Marconi took portable receiving equipment to St. John's,
Newfoundland for the historic experiment. His apparatus was installed in
an unused hospital building on Signal Hill (Figure 1), and his receiving
aerial wire was held aloft by a kite. The Poldhu station was instructed
to transmit the three dots of the letter "S" in Morse Code repeatedly
during specified hours, and in the early afternoon of December 12, 1901,
the signal was heard several times fading in and out of the background
interference. Transatlantic radio had been proven possible!
Not everyone believed that the feat really had been achieved. Indeed, in spite of Marconi's subsequent successes, some skeptics argue today that the wavelength was inappropriate, that Marconi's assistant, Kemp, was deaf, etc.. Certainly the Anglo-American Telegraph Company, which held a monopoly on telegraph communications in Newfoundland, believed it. Fearing that radio might compete with their transatlantic cable, they threatened Marconi with legal action if he continued his experiments. Marconi packed up and sailed to Cape Breton, Nova Scotia, on December 24. A prior invitation from Alexander Graham Bell in Baddeck assured him of a friendly reception.
The details of Marconi's arrival in Cape Breton depend on the story teller. According to Michael MacKenzie, a disheartened Marconi was walking down Charlotte Street in Sydney when he was welcomed by W.S. Fielding, a Cape Bretoner who was the federal minister of Finance.(1) On the other hand, Mary K. MacLeod's well-documented account describes a welcoming party of prominent citizens, including Premier George Murray, and shows a photograph of a sizable gathering on the dock at North Sydney with the Italian flag flying.(2) In any case, Marconi received the red carpet treatment in Cape Breton, including guided tours to find a suitable location for a permanent station, a federal grant of up to $80,000 to build it, and free land. He chose Table Head, a promontory overlooking the Atlantic Ocean in the bustling coal mining town of Glace Bay, as the site for the North American station of his proposed trans-Atlantic radio service. In return for the federal grant, his agreement with the federal government included special rates for the government and the press, and stipulations about Canadian content in the station that gave the agreement a distinctly modern ring.(3)
Construction of the Glace Bay station proceeded at an amazing rate, considering that it was a technological leap into the unknown. The antenna was an inverted pyramid of wires supported by four wooden latticework towers over two hundred feet high arranged on a square that was about two hundred feet on a side. The new antenna design was also used at Cape Cod and Poldhu. This impressive antenna array gave the station an external appearance that would make it recognizable as a radio station today (Figure 2). Inside, it was a different story. The spark transmitter and the magnetic or coherer detectors used for reception are all relics of a bygone era.
Finally, on the night of December 15, 1902, Marconi transmitted the first official radio message to Poldhu. (Since the Newfoundland experiment he had learned that transatlantic transmissions worked better at night at the wavelengths he was using). It was a short greeting to the Times newspaper of London from its correspondent, Dr. Parkin, in Glace Bay. On the following nights congratulatory messages were sent to and between heads of state in North America and Europe. Messages from the United States were transmitted from Cape Cod, and relayed across the Atlantic from Glace Bay.(4)
This was the beginning of transatlantic wireless communications. It was also the beginning of a rivalry between Marconi and the telegraph cable companies that the legal impasse in Newfoundland had only delayed. Cable operators had already begun to fret in a humorous vein less than two weeks after Marconi's Newfoundland experiment. The staff of the cable station at North Sydney sent the following message to the cable office in Liverpool, England.(5)
Best Christmas greetings from North Sydney,
Hope you are sound in heart and kidney,
Next year will find us quite unable,
To send exchanges o'er the cable:
Marconi will our finish see,
The cable co's have ceased to be;
No further need of automatics,
Retards, resistances and statics.
I'll then across the ether sea,(6)
Waft Christmas greetings unto thee.
Don't be alarmed, the cable co's
Will not be dead as you suppose.
Marconi may have been deceived,
In what he firmly has believed.
But be it so, or, be it not,
The cable routes won't be forgot;
His speed will never equal ours;
Where we take minutes, he'll want hours.
Besides, his poor weak undulations,
Must be confined to their own stations;
This is for him to overcome,
Before we're sent to our long home.
Don't be alarmed my worthy friend,
Full many a year precedes our end.
Thanks, old man for the soothing balm,
Which makes me resolute and calm.
I do not feel the least alarm,
The signal "s" can do no harm;
It may mean "sell" to anxious sellers;
It may mean "sold" to other fellers.
Whether 'tis "sold" or simply "sell",
Marconi's "s"; may go to --- well!
Although the stock market jitters predicted by these cable poets came to pass, their long term optimism was also justified. Trans-oceanic cables survived and multiplied, and cable and wireless are complementary mainstays of the world communications network today.
Unfortunately, the first congratulatory radio messages did not mean that Marconi had reached his goal of a commercial service with paying customers that would rival or exceed the transatlantic cable. The first short messages took hours to send, and had to be repeated many times, because reception was extremely variable. These unpredictable variations in signal strength were caused by natural fluctuations in the ionosphere, but this was not understood at the time. Experiments with the apparatus at the stations to overcome these difficulties extended over the next two years, during which time the press grew critical and investors became restless. These experiments included doubling the power input to the station from seventy-five to one hundred fifty kilowatts, increasing the size of the antenna by adding outlying poles, and increasing the wavelength used (i.e., decreasing the transmitter frequency).(7) Although insufficient, these changes all produced improvements, and indicated the directions in which Marconi should proceed.
In 1904 the company decided to gamble on building two larger and more powerful stations to replace Poldhu and Table Head. Sites were chosen at Clifden on the west coast of Ireland, and at a location just south of Glace Bay that is now called Marconi Towers. (This site is erroneously called Port Morien in several historical sources). The Marconi Towers station was built in 1905 and the Clifden station was completed in 1907. After further experimentation and improvements during this period, success was finally achieved. A public service began between the stations on October 17, 1907, with ten thousand words being exchanged on the first day (See Figures 3 and 4.)
Transatlantic radio service
begins at Marconi Towers
Marconi at Marconi Towers
"Only those who worked with Marconi these (past) four years realize the wonderful courage he showed under frequent disappointments, the extraordinary fertility of his mind in inventing new methods to displace others found faulty, and his willingness to work, often for sixteen hours at a time when any interesting development was being tested. At the same time the Directors of the Marconi Company showed wonderful confidence in Marconi, and courage in continuing to vote the large sums necessary from year to year until final success was achieved."(8)
The scale of the new stations at Marconi Towers and Clifden was impressive, even by modern standards. Their electric power input of a few hundred kilowatts was provided by their own power houses, burning coal at Marconi Towers and peat at Clifden. The first antenna array at Marconi Towers was an umbrella of wires approximately two thousand feet in diameter, supported at the centre by the four wooden towers from Table Head, and around the outside by a circle of tall wooden masts. The original transmitter building burned down in 1909, and was replaced by one that was equipped to specifications similar to Clifden. (See Figures 5 to 11 for further details).
Marconi Towers station,
Power house boilers
Steam engine and alternator in power house
Five kilovolt DC generators in power house
Twelve kilovolt standby battery
Top view of condenser plates
The heart of the station was the spark transmitter. It was still based on the principles devised by Hertz in the 1880's, but enlarged to great proportions. It was of the "rotary gap" type, in which a large metal wheel with studs spaced regularly around its edge rotated rapidly between two electrodes. Each time a pair of studs passed between the electrodes, a high voltage electric spark jumped the gap, and a pulse of radio waves was radiated by the transmitting antenna high overhead. The regular spark rate of a few hundred per second gave the dots and dashes of the Morse Code a musical pitch that helped the operator on the other side of the Atlantic distinguish the signals from atmospheric and man-made radio interference. In general, the most striking difference between this transmitting station and a modern one was that its radio signal was generated by electrical machinery. What we would describe today as electronics had not yet entered upon the scene.
The receiving apparatus of this period was similarly devoid of modern electronics. It consisted mainly of a very large antenna, circuits for tuning to Clifden's frequency, and either magnetic or Fleming valve detectors. The latter was a diode (two electrode) vacuum tube, and was the first truly electronic device to be used at the Marconi stations. Equipment to record incoming signals was added in later years.
The Marconi Towers station occupied about five hundred acres of land; the large area being required for the antenna arrays. In addition to the power house, transmitter building, and smaller operational buildings, there was a residence for the station manager and his family. Just after the station was built, Marconi and his new bride Beatrice moved into the residence with the station manager, Vyvyan, and his wife. Beatrice was from Irish gentry, and found this arrangement quite confining in comparison to the manor house accommodations to which she was accustomed. During the next two years Marconi and Beatrice travelled back and forth between Great Britain and Canada while he endeavoured to make the transatlantic service operational. Their last stay at Marconi Towers led up to the final success in 1907.(9)
A limitation of the transatlantic system was the fact that the transmitting and receiving facilities were located at the same station. When the transmitter was operating, its strong signal would drown out the weak signal from overseas. Consequently the stations took turns transmitting and receiving, and messages could only be sent across the ocean in one direction at a time. The remedy was to build receiving stations far enough from the transmitters to minimize interference from them. By 1913, transatlantic business had grown enough to warrant it, and receiving stations were opened at Letterfrack, Ireland, and at Louisbourg, Nova Scotia. These stations doubled the capacity of the system by allowing simultaneous message traffic across the ocean in both directions. Telegraphers called this a "duplex" system, whereas the former one-way-at-a-time system was called a "simplex" one.
By now, after years of trial and error, Marconi realized that reliable twenty-four hour transatlantic communications could be obtained by using much longer wavelengths and lower frequencies than he had used in his early attempts. Marconi Towers transmitted to Letterfrack on a wavelength of 8000 metres (37.5 kilohertz) and Clifden transmitted to Louisbourg on a wavelength of 5500 metres (54.5 kilohertz). Tuning, the ability to minimize interference between radio signals by transmitting and receiving at a designated frequency or wavelength, had improved greatly compared to early spark systems, but likely would not meet modern regulatory standards.
The Louisbourg station was located near "the old town", close to the shore of a part of the harbour that is now cut off by the causeway to the restored fortress. The buildings were grouped around a driveway running roughly east-west, behind which the line of towers supporting the main receiving aerial continued into the woods in roughly the same direction (Figure 12). These buildings included the receiver house, the manager's residence, two duplex houses for married staff, a three story staff residence called "the hotel", a workshop and a stable. The receiver house was the main operations building, and contained the receiving equipment, the land lines and telegraph room, the office, and some electrical generating equipment. A barracks was built to house soldiers of a Highlanders regiment that guarded the station during World War One. Photographs show a staff of twenty-two at Louisbourg in 1920 and a staff of twenty-six at Marconi Towers in 1908. These likely included only those deemed professional staff.
Marconi Wireless transatlantic
Marconi land lines room
Since the Louisbourg station initially had no means of amplifying incoming signals electronically, it required a gigantic receiving antenna to collect enough energy to operate its detection and recording apparatus. The aerial wire was approximately one kilometre long, and was supported by six towers that were about 330 feet (100 metres) high. These were 300 foot steel towers surmounted by wooden topmasts. The steel portions consisted of tubular sections bolted together, a type of construction called a "Gray tower" after its designer, Andrew Gray.
The first receiving apparatus at Louisbourg employed crystal detectors like the popular "crystal sets" that were used to receive the first radio broadcasts. The volume of the Morse Code signal was boosted by electromechanical audio amplifiers called "Brown Relays". Incoming messages were recorded on cylindrical "Dictaphone" style records for later transcription, and transmitted messages were punched on paper tape and fed into machines that automatically converted them into transmitted code. These semi-automatic arrangements made efficient use of the transatlantic radio link by allowing messages to be transmitted and received at a rate that would be too fast for human operators. The station was connected to telegraph networks so that incoming radio messages could be relayed to their North American destinations. It was also connected by land lines to Marconi Towers so that Louisbourg operators could operate the transmitter remotely, and relay incoming telegraph messages overseas by radio (Figure 13). Thus the Louisbourg station became the North American communications centre for the transatlantic radio service.
In the following years the principal layout of the Louisbourg station did not change much, but the Marconi Towers station underwent significant modifications. 1911 station plans show that the original umbrella antenna had been replaced by large transmitting and receiving arrays supported by lines of towers. The linear arrangement of the antennas, aligned on a great circle route to Ireland, was a consequence of Marconi's discovery that best results were obtained by pointing a horizontal aerial wire directly away from the intended source or receiver of the signals. A 1922 plan does not show the receiving facilities, presumably because they had been transferred to Louisbourg, but includes a press station, some small operational buildings, a staff residence, and several cottages.
Both the Louisbourg and Marconi Towers stations were greatly affected by the march of technological progress, which first carried them into the age of electronics, and then rendered them obsolete. In 1906, Lee DeForest, an American, invented the triode vacuum tube, called the "valve" in Great Britain. It revolutionized radio and ushered in the age of electronics. Development of the "tube" proceeded slowly at first, but was accelerated by military needs in World War One. The tube was capable of both amplifying radio signals in receivers and generating them in transmitters. Receivers became thousands of times more sensitive, and receiving antennas no longer needed to be giants like the one at Louisbourg. At Marconi Towers, racks of silently glowing vacuum tubes replaced the ear-splitting spark (Figure 14). The huge condenser (Figure 10) that energized the spark was no longer needed, and the transmitter building was shortened from about one hundred sixty feet to its present length of about sixty feet, perhaps to reduce taxes.
The smooth "continuous wave" generated by tubes permitted the transmission of speech and music, resulting in the broadcasting boom of the 1920's. The first east-to-west transatlantic voice transmission was made from a Marconi station in Ballybunion, Ireland to the Louisbourg station in 1919. This transmission demonstrated the rapid progress in vacuum tube design. The Ballybunion transmitter used only three high powered tubes, whereas a transmission from Arlington, Virginia, to Paris, France in 1915 required three hundred smaller ones.(10)
The vacuum tube could also operate at higher frequencies, corresponding to radio waves of shorter wavelength. Amateur operators reported occasional long distance transmissions using relatively low power at the new short wavelengths. Marconi systematically investigated the potential of "short wave" radio for long distance communications and found it to be more efficient than the "long wave" that his stations were using. He then boldly changed his proposal for a British Empire radio network, which had been shelved during World War One, from long wave to short wave. The British government accepted his proposal subject to stringent requirements regarding reliability and message handling capacity. The first link was between London and Montreal. It opened in 1926 and met its requirements with flying colours.(11) In succeeding years the British Empire short wave "beam" system was completed,(12) and Marconi had finally achieved his dream of a worldwide radio network.
The long wave transatlantic service with its Cape Breton stations was now obsolete, and closed in 1926. The Louisbourg station was dismantled, and its buildings were demolished or moved. Marconi Towers remained in use to provide marine radio services with the call letters V.A.S., nicknamed the Voice of the Atlantic Seaboard. Voice broadcasting was added to this service, and older Cape Breton residents can remember broadcasts for mariners and the occasional concert before commercial broadcasting began in the area. Marconi Towers was closed after World War Two in 1945, and the property and buildings were sold to Russell Cunningham, a local resident.
Since 1945, the former residence of Marconi and the station managers has been the home of the Cunningham family. After Russell Cunningham and his wife Violet passed away it became the home of their son Douglas, his wife Diane, and their family. They have restored the house to good condition and have maintained its basic structural authenticity (Figure 15). The interior and many of the furnishings appear to be much the same as in Marconi's day.
Remains of the transmitter building
The same cannot be said of the other station buildings. All that remains of them is the part of the transmitter building that was left in 1945, and it is in derelict condition (Figure 16). The corrugated iron roof and siding are badly rusted and full of holes, and the interior wooden floors and walls are in a semi-collapsed state. The fact that the building still stands is due to its solid frame of steel girders. The surviving part of the building is the central part of the post-1909 building that once contained the spark transmitter, battery, and part of the condenser shown in Figures 9 to 11. Few artifacts remain from the spark era, but with the aid of old photographs and a practiced eye, the original layout can be deduced from such clues as the hangers that supported the battery cells and condenser plates, the letters V.A.S. painted on a wall in later years, etc.
The house and remains of the transmitter building are relics of Nova Scotia's important role in the history of communications, and are the last structural remnants of the original transatlantic service in the world today. Parks Canada operates an interpretive centre at Table Head that contains a model of the station and a photographic exhibit telling the story of Marconi's early work. The Marconi Towers property has been designated a provincial heritage site, but at the time of writing, no steps have been taken to preserve or interpret the Marconi Towers or Louisbourg Marconi station sites for the public.
1. Michael MacKenzie, It Happened Yesterday (Grand Falls, Newfoundland:
Robinson-Blackmore Printing & Publishing Ltd., 1981), p. 81.
2. Mary K. MacLeod, Whisper In The Air, Marconi, The Canadian Years (Hantsport, N.S.: Lancelot Press, 1992), p. 56.
3. MacLeod, Ibid., p. 60.
4. A message from President Theodore Roosevelt to King Edward VII, transmitted from Cape Cod to Glace Bay, was received in its entirety at Poldhu on January 18, 1903, and became the first transatlantic radio message originating in the United States.
5. Donald McNicol, Radio's Conquest Of Space (New York, Toronto: Murray Hill Books, Inc., 1946), p. 142.
6. The ether or aether was a hypothetical all-pervading medium in which electromagnetic waves were supposed to travel. Physicists discarded this concept in the early 1900's.
7. R.N. Vyvyan, Wireless Over Thirty Years (London: George Routledge & Sons Ltd., 1933), pp. 42, 43.
8. Vyvyan, Ibid., p. 46.
9. Degna Marconi, My Father, Marconi (Ottawa: Balmuir Book Publishing Ltd., 2nd edition revised, 1982), pp. 150 - 154.
10. W.J. Baker, A History Of The Marconi Company (London: Methuen & Co. Ltd., 1970), p. 184.
11. Baker, Ibid., p. 224.
12. It was called a "beam" service because the signals were beamed at a particular country or area of the world. Beaming was practical at short wavelengths, but not at long ones, because a beam antenna must be many wavelengths in size.
Figure 1. Collection of the author; original unknown.
Figure 2. Canadian Marconi Company, Montreal.
Figure 3. Public Archives of Nova Scotia.
Figure 4. Public Archives of Nova Scotia.
Figure 5. Beaton Institute, University College of Cape Breton.
Figure 6., GEC - Marconi Co., Chelmsford, England.
Figure 7. GEC - Marconi Co., Chelmsford, England.
Figure 8. GEC - Marconi Co., Chelmsford, England.
Figure 9. GEC - Marconi Co., Chelmsford, England.
Figure 10. GEC - Marconi Co., Chelmsford, England.
Figure 11. Canadian Marconi Co., Montreal.
Figure 12. Notman Archive, McCord Museum, Montreal.
Figure 13. GEC - Marconi Co., Chelmsford, England.
Figure 14. Douglas Cunningham, Marconi Towers.
Figure 15. Collection of the author.
Figure 16. Collection of the author.
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