George Stibitz

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George Stibitz
George Stibitz.jpg
Born (1904-04-20)April 20, 1904
York, Pennsylvania
Died January 31, 1995(1995-01-31) (aged 90)
Hanover, New Hampshire
Alma mater Cornell University
Union College
Denison University
Notable awards Harry H. Goode Memorial Award (1965)
IEEE Emanuel R. Piore Award (1977)

George Robert Stibitz (April 20, 1904[1] – January 31, 1995) is internationally recognized as one of the fathers of the modern first digital computer. He was a Bell Labs researcher known for his work in the 1930s and 1940s on the realization of Boolean logic digital circuits using electromechanical relays as the switching element.

Stibitz was born in York, Pennsylvania. He received his bachelor's degree from Denison University in Granville, Ohio, his master's degree from Union College in 1927, and his Ph.D. in mathematical physics in 1930 from Cornell University.


This bronze plaque is located in the entryway of McNutt Hall at Dartmouth College reads, "In this building on September 9, 1940, George Robert Stibitz, then a mathematician with bell telephone laboratories, first demonstrated the remote operation of an electrical digital computer. Stibitz, who conceived the electrical digital computer in 1937 at Bell Labs, described his invention of the "complex number calculator" at a meeting of the Mathematical Association of America held here. Members of the audience transmitted problems to the computer at Bell Labs in New York City, and in seconds received solutions transmitted from the computer to a teletypewriter in this hall."
The site of the first long-distance communication of man and computer: McNutt Hall at Dartmouth College, September 9, 1940. The bronze commemorative plaque is mounted on the left wall in the entryway of the hall.

In November 1937, George Stibitz, then working at Bell Labs, completed a relay-based calculator he dubbed the "Model K" (for "kitchen table", on which he had assembled it), which calculated using binary addition.[2] Replicas of the "Model K" now reside in the Smithsonian Institution, the William Howard Doane Library at Denison University and the American Computer Museum in Bozeman, Montana where the George R. Stibitz Computer and Communications Pioneer Awards are granted. Bell Labs subsequently authorized a full research program in late 1938 with Stibitz at the helm. Their Model 1 Complex Calculator, completed in November 1939, was able to do calculations on complex numbers.[3] In a demonstration to the American Mathematical Society conference at Dartmouth College in September 1940, Stibitz used a teletype to send commands to the Model 1 Complex Calculator in New York over telegraph lines.[4] It was the first computing machine ever used remotely. (See the commemorative plaque and the hall where this event took place in the photos below.)


Stibitz held 38 patents, in addition to those he earned at Bell Labs. He became a member of the faculty at Dartmouth College in 1964 to build bridges between the fields of computing and medicine, and retired from research in 1983.

Computer art[edit]

In his later years, George "turned to non-verbal uses of the computer". Specifically, he used a Commodore-Amiga to create computer art. In a 1990 letter written to the department chair of the Mathematics and Computer Science department of Denison University he said:

I have turned to non-verbal uses of the computer, and have made a display of computer "art". The quotes are obligatory, for the result of my efforts is not to create important art but to show that this activity is fun, much as the creation of computers was fifty years ago.

The Mathematics and Computer Science department at Denison University has enlarged and displayed some of his artwork.


See also[edit]


  1. ^ Some sources say April 20, see Smiley p. 56.
  2. ^ Ritchie, David (1986). The Computer Pioneers. New York: Simon and Schuster. p. 35. ISBN 067152397X. 
  3. ^ Ritchie 1986, p. 38.
  4. ^ Ritchie 1986, p. 39.


  • Melina Hill, Valley News Correspondent, A Tinkerer Gets a Place in History, Valley News West Lebanon NH, Thursday March 31, 1983, page 13.
  • Andrew Hodges (1983), Alan Turing: The Enigma, Simon and Schuster, New York, ISBN 0-671-49207-1. Stibitz is mentioned briefly on pages 299 and 326. Hodges refers to Stibitz's machine as one of two "big relay calculators" (Howard H. Aiken's being the other one, p. 326).
"The second American project [Aiken's being the first] was underway at Bell Laboratories. Here the engineer G. Stibitz had first only thought of designing relay machines to perform decimal arithmetic with complex numbers, but after the outbreak of war had incorporated the facility to carry out a fixed sequence of arithmetical operations. His 'Model III' [sic] was under way in the New York building at the time of Alan Turing's stay there, but it had not drawn his attention." (p. 299)
Stibitz's work with binary addition has a peculiar (i.e. apparently simultaneous) overlap with some experimenting Alan Turing did in 1937 while a PhD student at Princeton. The following is according to a Dr. Malcolm McPhail "who became involved in a sideline that Alan took up" (p. 137)); Turing built his own relays and "actually designed an electric multiplier and built the first three or four stages to see if it could be made to work" (p. 138). It is unknown whether Stibitz and/or McPhail had any influence on this work of Turing's; McPhail's implication is that Turing's "[alarm]about a possible war with Germany" (p. 138) caused him to become interested in cryptanalysis, and this interest led to discussions with McPhail, and these discussions led to the relay-multiplier experiments (the pertinent part of McPhail's letter to Hodges is quoted in Hodges p. 138).
  • Ritchie, David (1986). "George Stibitz and the Bell Computers". The Computer Pioneers. New York: Simon and Schuster. pp. 33–52. ISBN 067152397X. 
  • Smiley, Jane, The Man Who Invented the Computer: The Biography of John Atanasoff, Digital Pioneer, Random House Digital, Inc., 2010. ISBN 978-0-385-52713-2.

External links[edit]