Slide Rules

Slide rule is a kind of oldest calculating device. On the base of Napier’s Logarithms theory, an English mathematician, William Oughtred invented Slide rule in 1620 AD.

- It is known as first analog device.

- It consists of two scales (rulers) and cursor.

- The outer scale is fixed and known as rule.

- The middle ruler can slide over the outer ruler and is known as slide.

- It is used to calculate multiplication, division or any other function.

Notes: -

        # Who was invented the Slide rule?

        -         William Oughtred

        # When was invented Slide rule calculating device?

        -         In 1620 AD