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Genaille-Lucas Rulers (or Rods) for Multiplication
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*Price and Stocks may change without prior notice
*Packaging of actual item may differ from photo shown
- Electrical items MAY be 110 volts.
- 7 Day Return Policy
- All products are genuine and original
About Genaille-Lucas Rulers (or Rods) For Multiplication
1891 invention that allowed the user to read off the results of simple multiplication problems directly, with no intermediate mental calculations. This set includes 11 wood laser engraved rods stored in the custom box. Each rod is 11" x ¾" x ¼" thick. In the days before calculators, methods of simplifying calculations were of much interest. In 1617 Napier also published a book describing a method to multiply, divide and extract square roots using a set of bars or rods. These became known as Napier's Bones. In the late 1800s, Henri Genaille, a French civil engineer, invented an improvement to Napier's Bones that eliminates the need to handle carries from one digit position to the next. The problem was posed by Edouard Lucas and thus the alternate name of Genaille-Lucas Rulers (or Rods) .The process of multiplying any integer of any length by a digit 1-9 is reduced to looking up numbers on the rods. Studying how and why these rods work can provide real insight into the nature of multiplication. We also make on a separate listing the Genaille-Lucas Rods for Division.
