Percy Ludgate

Source: Wikipedia, the free encyclopedia.

Percy Edwin Ludgate
Accountancy
(1917)
InstitutionsKevans & Son (Dublin, Ireland)

Percy Edwin Ludgate (2 August 1883 – 16 October 1922) was an

Turing-complete computer) in history.[1][2]

Life

Ludgate was born on 2 August 1883 in

Rathmines College of Commerce, earning a gold medal based on the results of his final examinations in 1917.[6] At some date before or after then, he joined Kevans & Son, accountants.[3]

Work on analytical engine

It seems that Ludgate worked as a clerk for an unknown corn merchant, in Dublin, and pursued his interest in calculating machines at night.[6] Charles Babbage in 1843 and Ludgate in 1909 designed the only two mechanical analytical engines before the electromechanical analytical engine of Leonardo Torres Quevedo of 1920 and its few successors, and the six first-generation electronic analytical engines of 1949.

Working alone, Ludgate designed an analytical engine while unaware of Babbage's designs, although he later went on to write about Babbage's machine. Ludgate's engine used multiplication as its base mechanism (unlike Babbage's which used addition). It incorporated the first

multiplier-accumulator
, and was the first to exploit a multiplier-accumulator to perform division, using multiplication seeded by reciprocal, via the convergent series (1 + x)−1.

Ludgate's engine also used a mechanism similar to slide rules, but employing unique, discrete "Logarithmic Indexes" (now known as

electromechanical) and fourth (electronic) types. The engine's precise mechanism is unknown, as the only written accounts which survive do not detail its workings, although he stated in 1914 that "[c]omplete descriptive drawings of the machine exist, as well as a description in manuscript" – these have never been found.[8]

Ludgate was one of just a few independent workers in the field of science and mathematics.[

Ludgate died of

Legacy

Plaque to Ludgate at his home in Drumcondra

In 1991, a prize for the best final-year project in the Moderatorship in

Trinity College, Dublin – the Ludgate Prize – was instituted in his honour,[11] and in 2016 the Ludgate Hub e-business incubation centre was opened in Skibbereen, where he was born.[6]

In October 2022, a plaque from the National Committee for Commemorative Plaques in Science and Technology was unveiled at Ludgate's home in Drumcondra by the Provost of Trinity College, Linda Doyle. (As can be seen in the photo, the year of birth is listed incorrectly on the plaque.)[12][13]

References

  1. ^ Ludgate, Percy E. (April 1909). "On a proposed analytical machine". Scientific Proceedings of the Royal Dublin Society. 12 (9): 77–91.
  2. ^ a b "The legend of Percy Ludgate, Skibbereen's early answer to Bill Gates". The Irish Times. 6 February 2003.
  3. ^ a b c Randell, Brian (2009). "Ludgate, Percy". Dictionary of Irish Biography. Retrieved 13 October 2021.
  4. The National Archives of Ireland
    . 1901.
  5. The National Archives of Ireland
    . 1911.
  6. ^ .
  7. .
  8. ^ Ludgate, P. E. (1914). "Automatic calculating machines". In Ellice Martin Horsburgh (ed.). Napier tercentenary celebration: Handbook of the exhibition of Napier relics and of books, instruments, and devices for facilitating calculation. Royal Society of Edinburgh. pp. 124–127.
  9. .
  10. ^ "The John Gabriel Byrne Computer Science Collection online catalog". www.scss.tcd.ie. Ireland: Trinity College Dublin.
  11. ^ "Percy E. Ludgate Prize in Computer Science" (PDF). www.scss.tcd.ie. Ireland: Trinity College Dublin.
  12. ^ "Science plaque unveiled to honour inventor Percy Ludgate". www.tcd.ie. 21 October 2022. Retrieved 22 October 2022.
  13. ^ "Unveiling of a Science Plaque to Percy Edwin Ludgate" (PDF). www.scss.tcd.ie. 15 October 2022. Retrieved 15 October 2022.

Bibliography