Amazon description:
"This is a reproduction of a book published before 1923. This book may have
occasional imperfections such as missing or blurred pages, poor pictures, errant
marks, etc. that were either part of the original artifact, or were introduced
by the scanning process. We believe this work is culturally important, and
despite the imperfections, have elected to bring it back into print as part of
our continuing commitment to the preservation of printed works worldwide. We
appreciate your understanding of the imperfections in the preservation process,
and hope you enjoy this valuable book. "
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Amazon
Tower Bridge:
"A visit to Tower Bridge Exhibition clearly explains how the Bridge works and
describes its fascinating history. The information below provides a backdrop to
help make the most of your visit.
The Need for a New Bridge
London Bridge was originally the only crossing for the Thames. As London grew,
so more bridges were added, although these were all built to the west of London
Bridge, since the area east of London Bridge had become a busy port. In the 19th
century, the East End of London became so densely populated that public need
mounted for a new bridge to the east of London Bridge, as journeys for
pedestrians and vehicles were being delayed by hours. Finally in 1876, the City
of London Corporation, responsible for that part of the Thames, decided the
problem could be delayed no longer.
The view today from the high level Walkways has changed dramatically, although
there are still signs of the area's amazing history. With the aid of photographs
and interactive kiosks, visitors to Tower Bridge Exhibition can gain a greater
understanding of how life would have been when the idea of a new bridge was
originally conceived.
How a Design was Chosen
A huge challenge faced the City of London Corporation - how to build a bridge
downstream from London Bridge without disrupting river traffic activities. To
generate ideas, the "Special Bridge or Subway Committee" was formed in 1876, and
opened the design for the new crossing to public competition.
Over 50 designs were submitted for consideration, some of which are on display
at Tower Bridge Exhibition. It wasn't until October 1884 however, that Horace
Jones, the City Architect, in collaboration with John Wolfe Barry, offered the
chosen design for Tower Bridge as a solution.
The Building of the Bridge
It took 8 years, 5 major contractors and the relentless labour of 432
construction workers to build Tower Bridge.
Two massive piers were sunk into the river bed to support the construction and
over 11,000 tons of steel provided the framework for the Towers and Walkways.
This framework was clad in Cornish granite and Portland stone to protect the
underlying steelwork and to give the Bridge a more pleasing appearance.
To learn more about the building of Tower Bridge, the people involved in its
construction and why it was needed, visit The Tower Bridge Exhibition where
video screenings explain the entire project, including the difficulties faced.
How it Works - Then and Now
When it was built, Tower Bridge was the largest and most sophisticated bascule
bridge ever completed ("bascule" comes from the French for "see-saw"). These
bascules were operated by hydraulics, using steam to power the enormous pumping
engines. The energy created was stored in six massive accumulators, as soon as
power was required to lift the Bridge, it was always readily available. The
accumulators fed the driving engines, which drove the bascules up and down.
Despite the complexity of the system, the bascules only took about a minute to
raise to their maximum angle of 86 degrees.
Today, the bascules are still operated by hydraulic power, but since 1976 they
have been driven by oil and electricity rather than steam. The original pumping
engines, accumulators and boilers are now exhibits within the Tower Bridge
Exhibition.
Tower Bridge Exhibition - A History
In 1910 the high level Walkways were closed to the public due to lack of use.
People arriving on the bridge preferred to wait at street level for it to close
rather then heading up the stairs carrying their heavy loads. In 1982, as part
of the new Tower Bridge Exhibition, visitors to the bridge could once again
enter the walkways, now fully covered, and experience the amazing panoramic
views. Although Tower Bridge is now powered by oil and electricity, the original
steam engines maintained by a dedicated team of technical officers remain in
their original location for all to see. This area is known as the Victorian
Engine Rooms, the second section of Tower Bridge Exhibition. Over the past 28
years, the exhibition has been developed to keep pace with modern day needs
without losing its Victorian essence. Through interactive kiosks and video walls
along with knowledgeable Guides, visitors can learn about key events in the
Bridge's history, ranging from Royal visits to dare devil stunts.
Interesting Facts
Tower Bridge has a fascinating history, which is explored in full in The Tower
Bridge Exhibition. Here are a few interesting facts you may not have known:
1910 - the high-level walkways, which were designed so that the public could
still cross the bridge when it was raised, were closed down due to lack of use.
1912 - during an emergency, Frank McClean had to fly between the bascules and
the high-level walkways in his Short biplane, to avoid an accident.
1952 - a London bus driven by Albert Gunton had to leap from one bascule to the
other when the bridge began to rise with the number 78 bus still on it.
1977 - Tower Bridge was painted red, white and blue to celebrate the Queen's
Silver Jubilee. (Before that, it was painted a chocolate brown colour).
1982 - Tower Bridge opened to the public for the first time since 1910, with a
permanent exhibition inside called The Tower Bridge Experience."
Source Tower
Bridge.