Sir Samuel Morland, diplomat and inventor, created three distinct calculating machines for King Charles II. His adding machine used a series of flat discs with pin-wheel mechanisms -- remarkably compact for the era. Unlike Pascal's Pascaline, Morland's adding machine did not propagate carries automatically; the user handled carries mentally. His multiplying machine used circular versions of Napier's bones, and his trigonometry calculator read values from engraved scales.
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