what is this bone?
It is a manually-operated calculating device for the calculation of products and quotients of numbers.
Napier's bones
Napier's bones is a manually-operated calculating device created by John Napier of Merchiston, Scotland for the calculation of products and quotients of numbers.
where does the irrational number e come from The first references to the constant were published in 1618 in the table of an appendix of a work on logarithms by John Napier. who is this person? He was a Scottish landowner known as a mathematician, physicist, and astronomer. what is his contribution in the field of mathematics? He is the discoverer of logarithms, invented the so-called "Napier's bones" and made common the use of the decimal point in arithmetic and mathematics.
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Napier's bones [SEP] Introduction
Napier's bones is a manually-operated calculating device created by John Napier of Merchiston, Scotland for the calculation of products and quotients of numbers. The method was based on lattice multiplication, and also called 'rabdology', a word invented by Napier. Napier published his version in 1617 in "Rabdologiæ", printed in Edinburgh, dedicated to his patron Alexander Seton. Using the multiplication tables embedded in the rods, multiplication can be reduced to addition operations and division to subtractions. Advanced use of the rods can extract square roots. Napier's bones are not the same as logarithms, with which Napier's name is also associated, but are based on dissected multiplication tables.