napier's bones
Học thuậtThân thiện
Definition
Noun: A calculating device invented by John Napier, consisting of a set of numbered rods or strips with marked scales. These rods were used to perform multiplication, division, and the extraction of square roots by manipulating the rods according to set rules, eliminating the need for memorized multiplication tables.
Usage
This term refers specifically to the historical calculating tool. It is used in contexts discussing the history of mathematics, computation, or John Napier's inventions.
Examples
- The museum's exhibit on the history of calculation featured a genuine set of Napier's bones.
- Before the slide rule, mathematicians and merchants sometimes used Napier's bones for complex calculations.
- His explanation of how to use Napier's bones to multiply two numbers was fascinating.
Advanced Usage
- The term is often used in its plural form ("bones") even when referring to a single set or the concept in general.
- It can appear in historical or technical descriptions: "The algorithm behind Napier's bones is based on lattice multiplication."
Variants and Related Words
- Napier's rods: An alternative name for the same device.
- Genaille-Lucas rulers: A later, modified version of the concept that allowed for reading results directly without carrying over digits mentally.
Synonyms
- Calculating rods
- Napier's rods
Notes on Meaning
The "bones" were typically made from ivory, bone, or wood, which is the origin of the name. The device is a significant precursor to more modern mechanical calculators.
Noun
- a set of graduated rods formerly used to do multiplication and division by a method invented by John Napier