enow.com Web Search

Search results

  1. Results from the WOW.Com Content Network
  2. Napier's bones - Wikipedia

    en.wikipedia.org/wiki/Napier's_bones

    Napier's bones is a manually operated calculating device created by John Napier of Merchiston, Scotland for the calculation of products and quotients of numbers. The method was based on lattice multiplication , and also called rabdology , a word invented by Napier.

  3. John Napier - Wikipedia

    en.wikipedia.org/wiki/John_Napier

    He also invented the so-called "Napier's bones" and made common the use of the decimal point in arithmetic and mathematics. Napier's birthplace, Merchiston Tower in Edinburgh, is now part of the facilities of Edinburgh Napier University. There is a memorial to him at St Cuthbert's at the west side of Edinburgh. [2]

  4. Promptuary - Wikipedia

    en.wikipedia.org/wiki/Promptuary

    The promptuary, also known as the card abacus is a calculating machine invented by the 16th-century Scottish mathematician John Napier and described in his book Rabdologiae [1] in which he also described Napier's bones. It is an extension of Napier's Bones, using two sets of rods to achieve multi-digit multiplication without the need to write ...

  5. Timeline of computing hardware before 1950 - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_computing...

    Scotsman John Napier reinvented a form of logarithms and an ingenious system of movable rods (1617, referred to as Napier's Rods or Napier's bones). These rods were based on the lattice or gelosia multiplication algorithm and allowed the operator to multiply, divide, and calculate square and cube roots by moving the rods around and placing them ...

  6. History of logarithms - Wikipedia

    en.wikipedia.org/wiki/History_of_logarithms

    The slide rule was invented around 1620–1630, shortly after John Napier's publication of the concept of the logarithm. Edmund Gunter of Oxford developed a calculating device with a single logarithmic scale; with additional measuring tools it could be used to multiply and divide.

  7. Genaille–Lucas rulers - Wikipedia

    en.wikipedia.org/wiki/Genaille–Lucas_rulers

    Genaille–Lucas rulers (also known as Genaille's rods) are an arithmetic tool invented by Henri Genaille, a French railway engineer, in 1891. The device is a variant of Napier's bones . By representing the carry graphically, the user can read off the results of simple multiplication problems directly, with no intermediate mental calculations .

  8. U.S. Presidents' Net Worth, Before and After Taking Office - AOL

    www.aol.com/15-presidents-net-worth-taking...

    George H.W. Bush. Before: $4 million. After: $23 million. The elder Bush had grown his net worth by 475% between the time he took office in 1989 and 2017, when The American University study was ...

  9. List of presidents of the United States - Wikipedia

    en.wikipedia.org/wiki/List_of_Presidents_of_the...

    The first president, George Washington, won a unanimous vote of the Electoral College. [4] Grover Cleveland served two non-consecutive terms and is therefore counted as the 22nd and 24th president of the United States, giving rise to the discrepancy between the number of presidencies and the number of individuals who have served as president. [5]