The soroban abacus handbook

THE ABACUS HANDBOOK - ZetaTalk

THE ABACUS HANDBOOK And here is a picture of a traditional Japanese Soroban. Here we have a streamlined instrument with 1 bead above the reckoning bar and 4 below it. Originally the Japanese Soroban looked much like the Chinese Abacus (5 beads below, 2 beads above) but it was simplified around 1850 and reduced to a single bead above the

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