Who, in 1642, constructed a mechanical calculating machine?
Mechanical calculator the arithmometer in the mid 19th century. Blaise Pascal invented a mechanical calculator with a sophisticated carry mechanism in 1642. After three years of effort and 50 prototypes he introduced his calculator to the public. He built twenty of these machines in the following ten years. This machine could add and subtract two numbers directly and multiply and divide by repetition. Since, unlike Schickard's machine, the Pascaline dials could only rotate in one direction zeroing it after each calculation required the operator to dial in all 9s and then (method of) propagate a carry right through the machine. This suggests
Monroe Calculating Machine Company January 1929 to February 1971. The "M" model further refined the "L". Monroe Calculating Machine Company The Monroe Calculating Machine Company was a maker of adding machines and calculators founded in 1912 by Jay Randolph Monroe based on a machine designed by Frank Stephen Baldwin. Now known as Monroe Systems for Business, the company was also known as "Monroe Calculating Machine Company," "Monroe THE Calculator Company," and "Monroe Division of Litton Industries." In 1911, Jay Randolph Monroe first saw the Baldwin Calculator, the invention of Frank Stephen Baldwin. Although Mr. Baldwin's machine had been patented in 1874 and had been