This portable 1st abacus would have been particularly useful for Roman engineers, merchants, and tax collectors. Columns can calculate fractions and single units on the right side, all the way up to
Traditioneller chinesischer Abakus / Rechner in Köln - Nippes | eBay Kleinanzeigen
Abacus - Wikipedia
Abakus - Wikipedia
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Abacus - Wikipedia
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Abacus - Wikipedia
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Frau, Die Abakus Spielt Lizenzfreie Fotos, Bilder Und Stock Fotografie. Image 83665930.
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old wooden abacus - obsolete calculator Stock Photo - Alamy
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