Heng, Zhang
Published: January 26, 2009, 2:14 am
Updated: December 10, 2010, 4:55 pm
This article has been reviewed by the following Topic Editor:
Peter Saundry
Zhang Heng (78 A.D.-139 A.D.), a Chinese mathematician and scientist who lived during the Han Dynasty. Heng is thought to have built the first seismoscope or seismometer in A. D. 132.
A model of Heng's seismoscope
The device worked on the principle of inertia wherein a mass is suspended. An earthquake shakes the vessel, causing a slight displacement between the mass and the vessel; this movement is transmitted via levers and gears to push out a ball. The surface of the vessel was decorated with motifs of mountains, tortoises, birds, animals, and antique writing. Around the vessel were eight dragons whose mouths held a ball. Around the base of the vessel sat eight corresponding toads with their mouths open, looking upwards. The sign for an earthquake was the falling of a ball from the dragon into the mouth of a toad. The direction of the earthquake was indicated by the position of the toad that swallowed the ball.
Further Reading
Are you absolutely sure you want to delete this article? This process cannot be undone and is permanent.
Yes, Delete This Article
Are you absolutely sure you want to remove this article? This process cannot be undone and is permanent.
Yes, Remove This Article
Citation
Cutler J. Cleveland (Lead Author);Peter Saundry (Topic Editor) "Heng, Zhang". In: Encyclopedia of Earth. Eds. Cutler J. Cleveland (Washington, D.C.: Environmental Information Coalition, National Council for Science and the Environment). [First published in the Encyclopedia of Earth January 26, 2009; Last revised Date December 10, 2010; Retrieved May 26, 2013 <http://www.eoearth.org/article/Heng,_Zhang>
The Author
Cutler J. Cleveland is Professor of Earth and Environment at Boston University, where he also is on the faculty of the Center for Energy and Environmental Studies. Professor Cleveland is Editor-in-Chief of the Encyclopedia of Energy (Elsevier, 2004), winner of an American Library Association award, the Dictionary of Energy (Elsevier, 2005), Handbook of Energy (Elsevier, forthcoming), and is the Founding Editor-in-Chief of the Encyclopedia of Earth. He is the recipient of the Adelma ... (Full Bio)
Zhang Heng (78 A.D.-139 A.D.), a Chinese mathematician and scientist who lived during the Han Dynasty. Heng is thought to have built the first seismoscope or seismometer in A. D. 132.
A model of Heng's seismoscope
The device worked on the principle of inertia wherein a mass is suspended. An earthquake shakes the vessel, causing a slight displacement between the mass and the vessel; this movement is transmitted via levers and gears to push out a ball. The surface of the vessel was decorated with motifs of mountains, tortoises, birds, animals, and antique writing. Around the vessel were eight dragons whose mouths held a ball. Around the base of the vessel sat eight corresponding toads with their mouths open, looking upwards. The sign for an earthquake was the falling of a ball from the dragon into the mouth of a toad. The direction of the earthquake was indicated by the position of the toad that swallowed the ball.
Further Reading
Are you absolutely sure you want to delete this article? This process cannot be undone and is permanent.
Yes, Delete This Article
Are you absolutely sure you want to remove this article? This process cannot be undone and is permanent.
Yes, Remove This Article
Site Options
0 Comments
Add Comment