Page 14 - Viva ICSE Computer Studies 5 : E-book

Mechanical Counting Devices

After early counting devices, mechanical counting Think and Discuss
devices were made. The limitations of the human How has the invention of mechanical

body’s ten fi ngers and ten toes apparently caused counting devices made calculations
early man to construct a tool to help him with easier and faster?
calculations.

Abacus

Abacus was the fi rst calculating machine invented in China to count large numbers.

It was a wooden rack holding two horizontal wires with beads strung on them. The
position of the beads was changed to enter a number. Simple calculations like addition,
subtraction, multiplication and division were performed using an Abacus.

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Abacus was the fi rst calculating device used to add and subtract numbers. It was developed in
3000 BCE in China. It was also called a counting frame.

Napier’s Bones

In 1614, John Napier invented a calculating device called Napier’s Bones. This device is a
set of rectangular rods marked with numbers. It was meant for simple calculations such

as addition, subtraction, multiplication and division of numbers. Later, it was improved
to fi nd the square root of numbers.

Electromechanical Counting Devices

Pascaline

Blaise Pascal invented the fi rst mechanical calculator in
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1642. It was named Pascaline. It had a box with eight
Pascaline was the fi rst
movable wheels called dials. The numbers for calculations
gear-driven calculator.
were entered with dials. It could add, subtract, divide and

multiply numbers as big as thousands.

Leibniz Calculator

Mathematician Gottfried Leibniz built a calculator in 1671 that could add, subtract,

multiply and divide numbers. It could also fi nd square roots.

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