napier's bones
Noun
Meaning
Alt. of Napier's rods
Source: Webster's dictionarySynonyms
Hypernyms
Examples
He invented a well-known mathematical artifact, the ingenious numbering rods more quaintly known as “Napier's bones,” that offered mechanical means for facilitating computation.
It was at this point that he designed his ' Napier's bones ', an abacus-like device that greatly simplified calculations that involved multiplication and division.