The Sumador Chino

On a recent motor trip through Mexico, the writer
came across on adding device which was referred 
to as a sumador chino (Chinese adder).  A survey of the more
available literature on the history of mathematics 
and on instruments of calculation has uncovered no reference
to such a device.  The purpose of this communication 
is to enlist the help of other members in bringing to
light whatever may be known concerning the evolution 
and present status of the sumador chino.

CACM November, 1960

Rogers, J. L.

CA601119 JB March 20, 1978  6:50 PM

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