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Cranes
Tower cranes are among the most familiar
equipment on construction sites around
the world.
Raising the bar:
a history of cranes
By Robyn Grimsley
Cranes have been around in one form or another for over 2 500 years, with the ancient Greeks and Romans using them to
construct their largest buildings, some of which still stand today. For much of the intervening time, these lifting devices
were human powered, and it was only with the Industrial Revolution that modern cranes came into being.
C
ranes have been, in one form or another,
the most commonly used lifting equipment
for large loads for centuries. Prior to
the introduction of the crane, construction,
particularly of large structures, would have
required significantly more labour, and the history
of the crane is closely tied to humanity’s history
of finding innovative ways to exceed their limits.
The Egyptian pyramids are one example
of structures built before the introduction of
the earliest cranes, most likely using a series of
ramps and thousands of labourers. The Colossi
of Memnon — two massive stone statues of the
Pharaoh Amenhotep III, weighing around 650t
each — were raised at the Theban Necropolis
nearly 3 500 years ago. Stonehenge is another
example of early lifting of massive loads, and
the prevailing theory is that the Sarsen stones
— the largest of which weighs 50t and making
transport by water impossible — were dragged
into place via a series of sledges, ropes, ramps,
and levers.
The history of the crane is closely tied to that
of the pulley. While the origin of the pulley is
unknown, the first known reference to the use
of the simple pulley to change pull direction is
in an Assyrian relief from the 9th century BCE.
The earliest evidence for the compound pulley
system is found in the Peripatetic Mechanica
(or Mechanical Problems), usually attributed to
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