Rhabdological abacus
1822-1824
Japanese abacus with case from the Japanese Chamber of Commerce & Industry
1996
Charles Cotterell's `Instrument for Arithmeticke' by Robert Jole
1677
Chinese abacus
before 1863
Arithmetical Jewel, 1619.
circa 1619
Chinese abacus, "Lotus - flower brand",
1900-1999
George Darwin's tidal abacus
1892
Replica of the Salamis abacus, half-size
1978