History of Computing Abroad

Engineering/Science

The UK was not far behind with its own scientifically inspired offerings. Three UK institutions in particular emerged as computing powerhouses: Manchester University, the National Physical Laboratory (NPL), and Cambridge University.

Some of Manchester’s first computer research was performed by Professor Max Newman, a former Colossus team member. At Manchester he established a group to work on the construction of a stored-program computer similar to the EDVAC design proposed in the United States by John von Neumann. The proposal was based around a specialized device call the Selectron tube, under development by the Radio Corporation of America, which at the time was one of the most promising digital storage devices. However, in the end his plans did not materialize: the Selectron tube ran into technical difficulties.

Meanwhile a completely independent computer had been built by the Electrical Engineering Department at Manchester. Designed by Freddie Williams and Tom Kilburn, this computer, the Manchester Mark I, was built on an entirely different form of storage based around conventional CRT’s, today referred to as Williams-Kilburn tubes. On June 21, 1948, an early experimental version of the machine, dubbed the Manchester “Baby”, became the first stored-program computer to run a program. The Mark 1 was used for a variety of purposes within the University in 1949 and 1950, including investigation of the Riemann hypothesis and calculations in optics.

At NPL another former Colossus team member, Dr. Alan Turing, joined the newly formed Mathematics Division where he set about designing his own universal computer. While Turing was also familiar with the von Neumann proposal, he was not inclined to copy the design. In February of 1946 he presented to the Executive Committee of NPL what is generally considered to be the first complete specification for an electronic stored-program digital computer, which he called the Automatic Calculation Engine (ACE). However the NPL was not equipped with the resources to construct his machine. Despite interest from other research laboratories, personnel with the capabilities to build Turing’s machine were scarce and most were already enlisted in other work, such as rebuilding the nation’s war-torn telephone system, or constructing machines for the nascent Department of Atomic Energy. Disappointed with the time it was taking to make progress, Turing left NPL before construction ever began. A scaled-down version dubbed the Pilot ACE was eventually completed in his absence, however, and ran its first program on May 10, 1950. It was put into useful service by the Mathematics Division, where it performed flutter calculations for the Canberra aircraft, calculations arising from the Comet disasters, the first simulation of road traffic control, and verification of Bullard's theory of geomagnetism.

Cambridge University Mathematical Laboratory was the third mainstay of early digital computing in Western Europe. Its Electronic Delay Storage Automatic Calculator (EDSAC) project, headed up by Maurice V. Wilkes, was conceived with the goal of producing a useable and reliable computing service to serve the University’s research needs. To this end, it was designed to be practical, and was based on tried and true technologies. As its name implies, the EDSAC design was influenced by the von Neumann EDVAC proposal. However in place of the unproven Selectron storage units proposed for use in the EDVAC, Wilkes opted for mercury delay lines, a technology that had already been put to use in radar systems. Derated vacuum tubes formed the core of its logic system, input was via 5-hole punched tape, and output was via a teleprinter. EDSAC ran its first programs on May 6, 1949, calculating a table of squares and a list of prime numbers. Its service to the University would continue into the 1960’s.