Chinese earthquake detector, artwork. This device was invented around 132 , by Zhang Heng. It consists of a copper-domed urn with dragons' heads c

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Chinese earthquake detector, artwork. This device was invented around 132 , by Zhang Heng. It consists of a copper-domed urn with dragons' heads circling the outside, each containing a bronze ball, and a pendulum hung from its top inside. When the Earth shook, the pendulum would swing, knocking a ball from one of the dragon heads into the open mouth of a bronze toad below. The direction of the earthquake's epicentre could be determined from which ball had been released.

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Size: 3780px × 2953px
Photo credit: © GARY HINCKS/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: -life, black, black--white, clay, close-, earth, electron, geographical, geography, geological, geology, heavy, life, micrograph, microscope, mineral, mineralogical, mineralogy, monochrome, nature, sample, samples, scanning, science, sem, soil, specimen, specimens, structure, white