Napier’s Bone:-
The Scottish mathematician John Napier invented system of algorithm in 1614 AD.The algorithm system makes the arithemetic calculation faster and easier .In 1617 AD he invented a calculating device called Napier’s Bone which were strips of bone with multiplication table inscribed on them.It consists of nine pieces of square cards and each cards were further divided into nine squares.It was used for multiplication and division.Even square roots and powers could be done.
Slide Rule
The Slide Rule was invented by William Oughtred in 1620 AD .This devices in made by using the principle of logarithms.A simple slide Rule consists of two graduated scales in which one scale slips upon the other.This devices is very easy to use.With the proper alignment of the two rulers,the user can perform simple multiplication and division problems.
Pascline:-
Blaise Pascal a French mathematician invented first mechanical calculator called pascaline in 1642 AD.He developed this machine to help in his father’s tax work.His father was french tax collector.Pascaline contains eight dials,gears and wheels.This numbers were entered by dialing a series of numbered wheels,where the movement of wheels started at 9 and moved to 0. An automatic carry over system was accomplished by rotating the adjacent wheel by one digit.This machine was capable of doing only additional and subtraction supporting only eight digits The numbers calculating capacity of Passcaline was 9 crores 99 lakhs 99 thousands 9 hundred and(9,99,99,999).Multiplication could be performed by repeated addition and division performed by repeated subtraction.
Stepped Rockoner:-
