written by Bernard
S. Finn
National Museum of History and Technology,
Smithsonian Instutution, Washington, DC 20560
Proceedings of the IEEE, Vol.64, No.9, September 1976
On Friday, 13 July 1866, the Great Eastern, by far the largest ship
afloat, left Valentia, Ireland, with 2730 nautical miles of cable in
her hold. Fourteen days later 1852 miles of this cable lay at the bottom
of the ocean, the ship was at anchor in Trinity Bay, Newfoundland, and
the old and new worlds were in permanent telegraphic communication.
The Great Eastern then turned back to the Atlantic where she successfully
grappled for and raised the end of a cable abandoned there the previous
year. A new section was spliced to the old, and on September 6 there
were two intact lines between Valencia and Heart's Content.
To operate these cables
at their western end a cable station was established at Heart's Content,
a small, isolated fishing community on the eastern side of the bay.
Five men came from England as employees of the Anglo-American Telegraph
Co. to act as operators. They shared quarters with operators of the
New York, Newfoundland, and London Telegraph Co., which controlled the
route that went by land (except for a short cable between Newfoundland
and Nova Scotia) to New York. The initial tasks were quickly accomplished;
instruments were set up, housing was constructed, and the basic routines
were established. In the pages that follow we are able to see what happened
next, as new techniques were introduced and as the needs of the staff
expanded. Through Heart's Content in the 1870's we discover some of
the early growing pains of a new and triumphant industry.
By 1870, the number of
cable operators had gradually grown to ten (including two supervisors),
working two on a cable around the clock (with both cables operating
between 10 a.m. and 6 p.m.). They received a paid vacation of three
months every three years, with a bonus of 25 pounds to help pay for
transportation back home to England. Wages for the newer members of
the staff, those who had arrived in 1869, were 150 pounds per year.
This was more than what was received at the other end, at Valentia,
but it still was not a princely sum, and the bachelors complained that
it was not enough to enable them to marry. Prices were relatively high
since most provisions were imported either from England or from larger
settlements across the peninsula. The only community of any real size
was St. John's, ninety difficult miles away. On the other hand, there
were few extra temptations. The nearest bar was in New Perlican, three
miles up the bay, and local diversion consisted mainly of hiking in
the barren uplands behind the town or boating in Trinity Bay. In the
winter even these pleasures were denied, though there was a billiards
table in the bachelors' mess and a small library. Drinking was frowned
upon; drunkenness, if it affected the job, was forbidden and was punished
by dismissal on the third offense. Interaction with the small local
fishing population was apparently very limited. The cable men were a
privileged outside group receiving steady wages, housed in quarters
built by the company, performing unworldly tasks with incomprehensible
tools.
From an objective point
of view perhaps the most remarkable aspect of this situation is that
the basic elements of it remained unchanged for a hundred years.
Heart's Content was not
the only remote cable station. Both the attenuation (by resistance)
and the smearing out (by capacitance) of the signal were proportional
to the length of the cable. This meant that if at all possible long
distances should be split into shorter lengths, with relay stations
inserted. Furthermore, cables should be kept away from areas where ships'
anchors or fishermen's trawling gear might damage them and therefore
remote locations were to be preferred. By the end of the 1870's, therefore,
places previously little-known (except perhaps as coaling stations)
became common names in cable vocabulary: St. Pierre and St. Vincent
Islands in the Atlantic, Jask in the Peruvian Gulf, Bahia (Pernambuco)
in Brazil, Banjoewani on Java. And among the remote islands later added
as key links in a world-wide communication network were Midway, Guam,
Yap and Fannning in the Pacific, Cocos and Mauritius in the Indian Ocean,
and St. Helena in the South Atlantic.
At each of these stations
there was or would be a small hardy group of expatriates, usually British,
manning and repairing the sensitive instrumentation.
But Heart's Content was
the most important of the remote stations, since it was ideally situated
on the North Atlantic route. It was a training ground for many who would
later serve all over the world. Because of a high volume of traffic
it was the place where much new instrumentation was introduced.
In 1870, two cables were
in operation. They consisted of stranded copper cores surrounded by
gutta percha insulation, a serving of jute as a cushion, and iron wires
to give the strength. Near shore these iron wires increased in size
to help protect the fragile core from tidal currents and anchors and
trawling gear. The basic design was not significantly different from
that of the ill-fated 1858 cable, with the exception that in 1858 the
outer wires were smaller and stranded, which made them more easily vulnerable
to the corrosive action of sea water. The major differences occurred
in the attention paid to details during he construction process. The
copper was tested for impurities (in 1858 conductivity of various sections
varied by as much as a factor of two), and repeated tests were made
on the completed cable to check for insulation and electrical continuity.
Equally important, the newer cable had been stored under water, protected
from heat and the direct rays of the sun,, which had undoubtedly had
a major role in the rapid deterioration of the earlier line. The new
cables were also designed to have a lower specific gravity to reduce
stresses during laying.
The 1858 cable might
be called a very expensive trial run. Clearly the promoters, Cyrus Field
et al., had no notion that there might be any electrical difficulties,
and their chief electrician, Wildman Whitehouse, was ill-trained to
deal with the unusual. Hence the physical indignities to which the cable
was put (especially lying in the sun on a wharf for the better part
of a year). In addition, it was Whitehouse's plan to use ordinary telegraph
receiving instruments on this nearly 2000-mile underwater line. And
when ordinary voltages failed to operate them he used induction coils
to force through two and three thousand volt pulses. This undoubtedly
sealed the cable's fate.
The situation was saved
only by the timely development by William Thomson of a mirror galvanometer.
In this instrument a very light mirror, with needle-like magnets glued
to its back, was carefully suspended inside a coil. Even a slight twist
of the mirror in response to signal pulses in the coil could be seen;
one direction for a dot, the other for a dash. Thus it was possible
to receive a few messages across the Atlantic during the summer of 1858.
Thomson's mirror galvanometer
was the receiving instrument used exclusively in 1866. It was found
to be most efficient if one man watched the dancing spot of light and
read off the dots and dashes while a second man wrote them down. A good
team could manage about eight words a minute. A very real advantage
to such a system was that if there was an obvious error, or a lapse
in attention, the man receiving could respond immediately at the end
of the message and ask for corrections. A major disadvantage was that
the instrument gave no record, and it was therefore impossible to go
back later to check the accuracy of what had been received.
In 1869 a competing French
transatlantic line was laid. Soon agreement was reached over rates and
over handling each other's traffic in emergency situations. This proved
especially valuable when both Heart's Content cables failed late in
1870 and could not be repaired until June of the following year. New
cables were laid to Heart's Content in 1873 and 1874. The old ones were
relegated to occasional use or stand-by status; they were officially
considered out of service in 1877.
The decade of the 1870's,
which is the period covered by this paper, was an exuberant and exciting
period for cable telegraphy. In the 1850's early optimism had been dampened
by some spectacular and expensive failures - most notably the 1858 Atlantic
attempt which worked marginally for slightly over a month, and the 1859-1860
cable down the Red Sea to India which never worked over its full length
at all. But a second line to India, though the Persian Gulf, in 1864
was a solid success; and confidence was completely restored with the
Atlantic crossings two years later - especially after the remarkable
achievement of picking up the lost end of the 1865 cable. Stimulated
by money that was freed when the British government purchased internal
land lines, telegraph promoters embarked on a virtual orgy of cable
laying. Approximately ninety thousand miles of cable were in use at
the end of the decade (compared to thirteen at the beginning), linking
all the inhabited continents together and to the larger island countries
of Japan, New Zealand, the Philippines, Cuba; island groups in the West
Indies, the East Indies, the Aegean were joined to each other and to
the larger network; and countries for which it was impossible or difficult
to employ land lines used cables to tie themselves more tightly together
(Denmark, Norway, Brazil, Argentina, Japan).
On the shorter lines
ordinary land-line techniques continued to be used with little modification.
On the longer cables the key plus mirror galvanometer made up the sole
transmission system. But the long cables were expensive, and least on
some routes the traffic potential was high. Thus there was considerable
incentive towards the development of new techniques which would increase
the message-handling speed. Two were developed in the 1870's with lasting
effect on the industry. Both were introduced immediately at Heart's
Content, and it is there that we will examine them. They were the siphon
recorder and duplex telegraphy.
After its origins, land-line
telegraphy had developed in an atmosphere virtually devoid of theory.
It was dominated by clever tinkerers and ingenious promoters. People
of the same type - John and James Brett, Lionel and Francis Gisborne,
Charles Bright, Cyrus Field, John Pender - treated the cables as mere
extensions of what was familiar on land. In retrospect we can only be
incredulous at the naivete with which, for instance, the first Atlantic
cable was promoted, the uncritical facility with which it was financed
and the almost reckless speed with which it was manufactured and laid.
Unfortunately there were significant novel phenomena that had to be
considered. As already mentioned, there was the right resistance, which
made quality control of the copper essential; the capacitance, which
could be calculated in terms of the properties of the dielectric used
around the copper core; and the relationships of these two to the shape
of the signal. In addition there were problems associated with laying
and picking up cable that weighed a ton or more per mile in air (and
considerably less when submerged) in waters up to two miles deep, especially
in terms of the strain that could be expected on the laying mechanism
and on the cable itself. And, as it turned out, there was more than
ordinary cleverness needed in the design of instrumentation,. Fortunately
a young professor from Glasgow, William Thomson, had been selected by
Scottish shareholders as a director of the company. For the next ten
years he devoted a considerable portion of his time and energy to solving
the above problems - observing them and creating solutions at first
hand by participation on all of the Atlantic cable expeditions (one
in 1857, two in 1858, one in 1865, and one in 1866), and conducting
several field tests. He designed and patented a number of instruments,
including the mirror galvanometer, which has already been mentioned,
and its successor, the siphon recorder, which became the principal receiver
for long cables for half a century.
Thomson patented his
siphon recorder in 1867 and improved it into practical form over the
next few years. A moving coil suspended between the poles of either
a permanent or electromagnet was attached by threads to a thin bent
glass tube or siphon. One end of the siphon dipped in an ink pot, the
other end was held horizontally opposite to, but not quite touching,
a moving strip of paper. In the early instruments the ink was electrified
intermittently by a small electrostatic generator, causing small dots
of ink to jump across the gap onto the paper tape. As the coil moved
under the influence of the fluctuating current, the siphon shifted from
side to side in front of the paper leaving a trace of dots to mark the
positive and negative pulses.
The first comment from
Heart's Content on the recorder apparently was made in October, 1873.
Between pleading for separate quarters for one of his men who was living
with his pregnant wife in the bachelors' quarters, which was "hardly
the place for her at such a time," and complaining about the cost
of living in a town where the butcher came once a week in the summer
and every other week in winter if he could, E. Weedon, the chief of
station, set down his opinions on such modern improvements: "I
have little faith in the recorder. Williams & Newitt, first class
recorder clerks, assure me that our speed with VA [Valentia] is fully
50 percent over the speed of the recorder they worked in the East."
But he did not prevail,
and one of the Thomson recorders was sent out for trial in the summer
of 1874. In October, Weedon was not optimistic: "The instrument
is undoubtedly a step in the right direction but it's a long way from
being perfect." He admitted, however, that there still hadn't been
a proper test due to a lack of the right kind of paper.
Or perhaps it was just
because October was a bad month, cold and damp. There was much sickness
among the children, and Weedon speculated that the refuse pits, which
presently were located behind the houses on the uphill side, might be
draining into the wells, which were dug in the basements. He decided
to have water-tight casks placed near the back doors. Cinders, ashes
and such should be placed in them during the day, "and other matter
more obnoxious the last thing at night." He could get a man to
cart it all away for £36 a year.
On December 2, he noted
simply that the recorder was "working well." But a week later
he reported "favorably of it in every way." The transmission
speed for the mirror and the recorder were the same, but the man using
the mirror had to ask for repetitions when he was uncertain. With the
recorder this was unnecessary, since he had the message on a slip of
paper. Weedon found, however, that one man on the recorder lost time
in checking the message before responding. Therefore, he strongly recommended
that two men be used - one to read and check the message, the other
to respond immediately when the message was completed. With such an
arrangement ten words a minute were easily achieved, versus eight with
the mirror or with just one man on the recorder.
In February 1875, with
plans well under way for a new office, Weedon was looking forward to
using recorders exclusively. He wanted to know if he could get two more
by September. When September came, the new office was still unfinished
and there were no additional recorders. In January 1876, he reaffirmed
his endorsement of recorders, noting that Valentia had its reservations
(due in part, perhaps, to the higher humidity there, which interfered
with the static charge).
Each year there was a
celebration at Heart's Content to mark the landing of the first cable.
It was not a very grand affair, Weedon reported. About a dozen friends
joined them, the Union Jack and Stars and Stripes were displayed, kerosene
lamps were hung about, and there was some piano music. However, 1876
may have been an exception (we have no report). Not assuredly, because
of the American centennial, but it was the tenth anniversary of operations
at Heart's Content, a new schoolhouse had been constructed with the
help of company funds, and they were preparing to move into a new station
building. The move took place on November 4, still with only one recorder.
The problem was apparently
with Valentia. They did not like the instrument. Early in 1878 Weedon
was pleading more strongly than ever, now estimating that the recorder
was 30 percent or perhaps even 50 percent better than the mirror in
terms of speed. Then he proudly announced that one of his men, Dickinson,
had made a recorder; furthermore, it cost only a sixth as much as Thomson's.
The management in London at least saw merit in persistence. Later that
spring they awarded Weedon an unexpected raise and gave Dickinson a £25 bonus. And in June Dickinson completed his second recorder.
The momentum had been
achieved, and by the end of the decade the battle had been won; recorders
were fully accepted. Indeed, in 1880, when a new cable was laid, a siphon
recorder was sent out to be used on it.
A second major innovation
of the 1870's was duplexing. For several years a number of inventors
had attempted to devise means by which two messages (or more) could
be sent over a land line at the same time. Two successful methods of
duplexing were developed. In the one that was ultimately widely used
on submarine cables, an "artificial line" (electrically equivalent
to the real line) was placed in parallel with the line receiver connected
between the two, and with other resistances leading to the key, battery
and ground. The result was a Wheatstone bridge in which, if properly
balanced, the outgoing current had a null effect on the local receiver.
In the second, "differential" system, the receiver contained two coils wound in opposite directions.
The sending current was split so that half went through one coil into
the line, the other half went through the other coil and then through
an artificial line to ground. This is the system introduced by Joseph
Stearns, when he arrived at Heart's Content in 1872 and attempted to
set up a duplex circuit over the short cable to Sydney, Nova Scotia.
When Weedon took over management of the line to New York in 1873 (as
a result of the Anglo-American Company absorbing the New York, Newfoundland
and London Enterprise), a new attempt was made to employ duplex over
the short land-cable line through Sydney to Port Hastings, Nova Scotia.
He achieved moderate success.
But in 1876 Weedon was
far from satisfied and was openly skeptical of the method having any
practical value.
Stearns came back two
years later in 1878, to duplex a full Atlantic cable using a bridge
arrangement. He was probably a welcome sight because, aside from the
success with the siphon recorder, it had not been a particularly good
year. The walls of the new station house were leaking, Weedon's physical
condition was deteriorating so that he found it increasingly difficult
to get around, and his attempts to raise money for a new church, which
included solicitation letters to everyone he could think of, including
Cyrus Field, had gone unanswered. Then two men received "last warnings" about their drinking, and the one who explained that his wife had driven
him to it received no sympathy. 'Ihere were also still loose ends from
a personal tragedy of the previous year. Isolation was no protection
from diseases like diphtheria which swept through the time to time,
often with fatal results for one or more of the children. But in 1877
one of the original group of men, Unicume, had died. Always in poor
health, he had been unable to obtain insurance, and his pension was
insufficient for his wife and three children. Weedon, who often took
a protective, even fatherly, view of his men, was executor of the small
estate. He worried over his responsibilities, at the same time trying
to get the company to assume some additional responsibilty in this hardship
case.
Perhaps then it is not
surprising that Weedon became caught up in the excitement of introducing
a new technique which would double the capacity of the lines. He wrote:
"Mr. Stearns and
myself have discussed Duplex a great deal since his arrival; I must
confess that until I saw his system I felt quite skeptical about Duplex
but having seen the way he gets his balance, and having produced a balance,
how steady it keeps in moderately severe temperature I am quite sanguine
of success. Mr. Stearns' visit of a few weeks here has learnt me more
about Duplex than I have been able to pick up from books in the course
of years; and you may rely upon it, the past few weeks experiences
will not be lost upon me."
Weedon was now a strong
advocate of duplex, especially after he made a slight change in the
circuit. Stearns had placed an isolating condenser between the bridge
and the battery; Weedon tried placing condensers at the terminals of
the cable and of the artificial line, isolating them from the rest of
the circuit. This was more in accord with ordinary practice, and Weedon
claimed the results were much improved. But there were still problems.
Thus he felt he had to take exception to the Directors' report, which
indicated that duplex was fully operational at 90 percent regular speed
in each direction. He emphatically stated it was still experimental,
and the final speed was still undetermined. Unfortunately, Weedons
design change had already been patented by Muirhead, Stearns' rival
in this art, which may have been a reason for Stearns reluctance
to accept it. Weedon accused Stearns of being stubborn, and it was well
into 1879 before duplexing was operational, if still a bit erratic.
The problem probably
lay in the artificial line, which was adopted by Stearns from a design
by C.F. Varley. A series of resistors were connected in series, which
connected between the junctions and ground. The greater the number of
resistors and capacitors, the closer the approximation to the real thing.
But this also meant more junctions and more possibilities for the effects
of contact voltage within the artificial line. The solution to this
problem was to keep a very even temperature and to be careful. Another
solution was a totally different design for the artificial line. This
was provided by Muirhead and Taylor in 1875. They designed artificial
line elements where the resistor was also one plate of a capacitor.
These elements became standard elements in artificial lines in the 1880's.
The introduction of these
new techniques can thus be seen to follow a classic pattern of stubborn
resistance to reluctant acceptance to even enthusiastic support. But
it also brought increased pressures on this small community of exiles
which are harder to document. Duplexing, plus more cables (the 1873
and 1874 cables effectively replaced the earlier two, but a new one
would arrive in 1880), demanded more men, crowding the already inadequate
housing facilities. The extra terminals and the artificial lines introduced
space pressure in the new station building almost before it was completed.
The men adjusted because they had to, and the system continued to work
and to prosper.
In 1880, Weedon could
look backward with a feeling of satisfaction and forward with some confidence.
His own physical condition had improved so that he could - on nice days
- walk the short distance between his house and the station. Mrs. Unicume
was marrying one of the other operators. Flowers bloomed in the specially
built window boxes in the new station. A new church was to be built
with the help of company funds. And the average message rate was about
1500 per day in each direction, or almost ten times what it was a decade
before.
(from https://www.ewh.ieee.org/reg/7/diglib/library/hearts-content/article/growing.html)
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