The telegraph had quickly become an important business tool. By
1830, there was a network of over a thousand telegraph towers
working together throughout Europe. However, the rising popularity
of the telegraph quickly led to congestion on the lines, and this
presented a new problem for the speedy delivery of information. In
London, England, for example, almost all telegraph traffic was
related to the London Stock Exchange and other business matters.
However, each wire could carry only a single message in a single
direction, and so the queue for sending and receiving information
became prohibitively long. By the 1850s, the lines were often so
congested that it could take hours and sometimes more than a day to
deliver a message to a station only a few hundred yards away.
This was particularly troublesome with the heavily trafficked
line between the Stock Exchange branch and the nearby Central
Telegraph Office. The Exchange would submit time-sensitive
information along that one thin wire, hoping the telegraph operator
could then relay it quickly to its destination to report important
changes in share values.
Josiah Clark, an employee of the Electric Telegraph Company, came
up with a novel solution. Rather than sending outgoing messages
across the wire, these could be placed on small cases and shot
through a pneumatic tube (a tube of compressed air that could be
controlled to carry items between two points). A tube was set up
between the telegraph office and the Exchange. The use of the wire,
then, could be designated to in-bound messages only. A year after
his 1853 test, Clark saw his vision made reality when an underground
tube was laid between the Exchange and the Telegraph Office.
Overall, this device was so successful that another tube, running
from a different branch office located further away, was installed
in 1858. After that, there was an explosion of pneumatic tube
delivery systems throughout England and France. By 1866, there were
pneumatic tube networks also functioning in Austria, Italy, the
United States, and even Brazil. These were subject to blockages,
however, and to air leaks that would slow message delivery.
The only sure solution lay in the development of wire set-ups
that could handle multiple messages, called the duplex system.
In 1872, an electrical engineer and sometime telegraph operator
from Massachusetts by the name of Joseph B. Stearns became the first
to create a successful duplex system. This type of line allowed for
the simultaneous transmission of two messages—one in each
direction—along the same wire.
In 1862, ten years before Stearns’ invention, a young inventor
from Ohio by the name of Thomas Edison had saved the life of the son
of J.U Mackenzie, railway stationmaster at St. Clemens, Michigan.
The boy had wandered onto the tracks, and Edison managed to pull him
of the way of an incoming boxcar just in time. As a token of
gratefulness, and to reward his courage, the stationmaster taught
Edison the art of telegraphy. By 1864, Edison had grown increasingly
interested in the theory of multiple message wiring, but Stearns had
beaten him in his quest to build the first working multiplex line.
Not to be outdone, however, Edison created the first quadruplex
system in 1874, and the duplex and quadruplex systems—both of which
cut down on the cost of building new wires—were eagerly adopted by
the major telegraph companies shortly thereafter. Edison went on to
invent electric lighting, and created a successful system for the
distribution of electricity to homes. He also invented the
phonograph, the first motion-picture camera, and the telescribe,
among many others. When he died in 1931, the man responsible for the
first quadruplex system had 1,093 U.S. patents in his name.
Following Edison’s invention, the push was on to create systems
that could send even more simultaneous messages. Among others,
Elisha Gray from Barnesville, Ohio, and Alexander Graham Bell (born
in Scotland but working from Brantford, Ontario, and Boston,
Massachusetts) both ended up tinkering with the Harmonic Telegraph.
Also known as the Musical Telegraph, this device transmitted
messages via sound. Its success would depend on the operator’s ear,
as he would have to pick out which messages were being delivered in
what tone. Bell soon realized his invention could be used to send
human vocalizations over a standard line. Gray ignored this
innovation, seeing it as merely another turn of events in the quest
to perfect telegraphy. In reality, however, it was the first faint
signal that the telegraph would be replaced by a new kind of
Besides, telegraph operators had a more immediate problem in the
form of an invention that threatened to render their profession all
but obsolete: the Auto-Transmission Hub.
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