Page 38 - Inventions - A Visual Encyclopedia (DK - Smithsonian)

Zhang Heng

▼ EARTHQUAKE INDICATOR
The most famous of Zhang’s inventions
One of the greatest scientists in Chinese history, Zhang was his seismoscope, or “earthquake
weather vane,” that could tell the direction
Heng combined being an inventor with a career as in which an earthquake had occurred.

a government official. He rose to become China’s
Each dragon head faces
chief astronomer, as well as an important advisor
a different direction.
EARLY BREAKTHROUGHS was also a famed mapmaker, poet, and artist.
to the Emperor. As if this was not enough, Zhang

WATER-POWERED
Rings were
ARMILLARY SPHERE
positioned to mirror
An armillary sphere is a framework
objects in space.
of rings that was used to understand
how planets and stars move the movement of
through the sky. Zhang’s big
idea was to use a waterwheel
to power the sphere’s
machinery so that it
turned automatically,
making one rotation
a year. Bronze urn
Pendulum inside drops a
ball through the dragon’s head
Replica of Zhang
Heng’s armillary facing the direction of the quake.
sphere, 1439
Figure always points
to set direction.
NAVIGATIONAL CHARIOT
Zhang may have also invented a device to indicate
direction. This was a “chariot” with a figure on top that
could be positioned to point in any direction. A complicated
Model of a
system of gears meant that no matter what path the chariot navigational
followed it continued to point in the same chariot from China,
direction, similar to the way a compass does. 2700–1100 bce

LIFE STORY

78 ce 95 ce 108 ce 112 ce
Zhang Heng is born near He leaves home to go to While working as a Zhang Heng is
Nanyang, a city in central Luoyang, China’s capital local official, he begins summoned by the
China. His father died at the time, to study at to publish papers about Emperor to work as an
when Zhang was just the Imperial Academy. astronomy and mathematics. official at the imperial
10 years old. court in Luoyang.

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