An Abacus
The number appearing on this Chinese abacus is 1,532,786.
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abacus
The American Heritage® Dictionary of the English Language, 4th edition Copyright © 2010 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

An example of an abacus used for arithmatic.
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