Tower Bridge
Hydraulic systems
· The original raising mechanism was
powered by pressurised water.
· In 1974, the original operating mechanism
was largely replaced by a new electro-
hydraulic drive system.
· During World War II, as a precaution
against the existing engines being
damaged by enemy action, a third engine
was installed in 1942.
Incidents
· In December 1952, the bridge opened while a
number 78 double-decker bus was on it. At that
time, the gateman would ring a warning bell and
close the gates when the bridge was clear
before the watchman ordered the lift. The
process failed while a relief watchman was on
duty. The bus was near the edge of the south
bascule when it started to rise; driver Albert
Gunter made a split-second decision to
accelerate the bus, clearing a three-foot drop
onto the north bascule, which had not started to
rise. There were no serious injuries.
· Before dawn on 31 October 2003, David Crick, a
annaabi.ee 
