Mathematician George Stibitz is born, April 20, 1904

-April 20, 2017


   Source: Denison University
George Stibitz spent his life using mathematics to solve problems, and today he is known as one of the fathers of the modern digital computer.

Born in York, PA, Stibitz showed an aptitude for science and mathematics from a young age. He received a bachelor's degree in applied mathematics from Denison University, before receiving a master of science from Union College, and a PhD in mathematical physics at Cornell in 1930. Shortly after, he began working as a research mathematician at Bell Telephone Laboratories.

In his research, Stibitz took an interest in automatic calculators that he hoped could replace the tedious manual calculations done at the time. In 1937, he completed a relay-based calculator that used binary addition, known as the Model K because it was assembled on his kitchen table.

Stibitz binary adder
Here is a replica of Stibitz's binary adder, which he built in his kitchen. Source: Bit by Bit
Stibitz had taken a few telephone relays home and fastened two of the relays to a board, cut strips from a tobacco can, and nailed them to the board for input. He used a dry cell and a few flashlight bulbs for output, and wired a binary adder.

Though his company didn't take an interst in the invention right away, it eventually led to Bell Labs' Complex Number Computer (CNC), which Stibitz designed with Samuel B. Williams in 1939. The Model 1 CNC had a panel containing about 450 relays and a teletype with a keyboard to enter mathematical problems and record answers.

In a demonstration in September 1940 at Dartmouth College, Stibitz transmitted a series of math problems over a phone line to the CNC in New York City, which returned the answers via teletype within seconds. It was the first remote computer operation.

During World War II, Stibitz joined the National Defense Research Council and worked to improve the CNC. The resulting Model 2 computer used punched tapes to store programs that gave the computer instructions so it could perform complex calculations many times on different sets of numbers.

After his career at Bell Labs, Stibitz became a consultant in applied mathematics and investigated how computers could solve biomedical problems as a professor at Dartmouth College. He also held 38 patents for inventions including a counting device, a record controlled scoring machine, and a stereophonic organ.

Among the many honors he received for his work were the Harry H. Goode Memorial Award and IEEE's Computer Pioneer Award. He died in 1995 at the age of 90.

Note: Some sources list Stibitz' date of birth as April 30.

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For more moments in tech history, see this blog. EDN strives to be historically accurate with these postings. Should you see an error, please notify us.

Editor's note: This article was originally posted on April 20, 2015 and edited on April 20, 2017.

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