Soroban, or Japanese Abacus

This abacus has an open wooden frame painted black and a wooden cross piece with an inset white strip on top. Twenty-three parallel wooden rods hold the beads. On each rod, there is one bead above the cross piece and four below. The beads are similar in shape to those on other Japanese abaci. Every third column of beads is marked with a black dot on the cross piece. The central column has two black dots and a red dot as well. Every fifth column is marked with a white dot. The abacus is stored in a cardboard box covered with decorated paper. There is no mark of a maker.

The instrument was given to the Smithsonian by G. Norman Albree, along with several circular slide rules of his design. According to the donor, his first introduction to the soroban was in 1958. He found addition and subtraction straightforward and bought this larger instrument to try multiplication and division. However, the beads were too small for his seventy-year-old fingers and thumb. Albree put the instrument aside, and returned to using logarithmic tables for multiplication and division.

Currently not on view