Blaise Pascal invented the Pascal line. ( Of course, the apparatus is named after him)
- It was designed between 1642 and 1644. It could only do addition and subtraction, with numbers being entered by manipulating their dials.
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William Oughtred invented the slide rule. Which could be used to perform multiplication and division.
- After John Napier invented logarithms, and Edmund Gunter created the logarithmic scales (lines, or rules) upon which slide rules are based, it was William Oughtred who first used two such scales sliding by one another to perform direct multiplication and division.
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