| More pictures available at links below. | ||
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The 7-rod abacus will allow one to manipulate numbers up to a value of 9,999,999. |
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Next picture: "Certainly this contraption is ..." Eric's Homepage |
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| More pictures available at links below. | ||
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The 7-rod abacus will allow one to manipulate numbers up to a value of 9,999,999. |
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|
Next picture: "Certainly this contraption is ..." Eric's Homepage |
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