IBM SPEAKERS BUREAU SLIDE SHOW

Slide 11
Napier's Rods

Each rod bears a multiplication table for a particular digit. Multiplication and division are handled by addition and subtraction. The rods were crude, but they did work and were used by several inventors in later machines. Napier, who is remembered for inventing logarithms, also introduced the use of the decimal point.

Until the mid-1950's, Blaise Pascal's calculator was thought to be the first attempt to mechanize the process of digital calculation.

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