Geoff Tootill

A Boy Who Built Radios

Geoffrey Colin Tootill — known as Geoff — was born on 4 March 1922 in Chadderton, Lancashire, England. He grew up in Birmingham, where as a boy he built radio sets and experimented with electronics.

Tootill won a scholarship to Christ's College, Cambridge, and began studying mathematics in 1940. During his studies he realised that engineering suited him better than pure mathematics. After graduating during the war, he entered government scientific work — a path that would lead him into the heart of early computing.

Wartime Radar at TRE

Tootill initially worked in operational research connected with Fighter and Bomber Commands. In 1943 he transferred to the Telecommunications Research Establishment (TRE) at Malvern, where he worked on airborne radar.

Frederic Williams and Tom Kilburn were already at TRE. The three men who would later build the Manchester Baby were working in the same wartime research establishment, though they did not yet know what they would achieve together.

The Manchester Team

After the war, Williams moved to the University of Manchester. Tootill joined the Manchester work in 1947 and worked closely with Tom Kilburn on the Williams-Kilburn CRT memory and on designing and building the Small-Scale Experimental Machine — the Baby.

The core Baby team was three people: Frederic Williams headed the wider research project, Tom Kilburn led the detailed computer design and wrote the first program, and Geoff Tootill made substantial engineering contributions and wrote another early program. Tootill was not merely an assistant — he was a core member of the development team.

On 21 June 1948 the Baby ran Kilburn's first program successfully. Tootill also kept an important laboratory notebook documenting the machine's development, which became a vital historical record.

The Human Side of the Lab

The Science Museum preserves Tootill's laboratory coat and a small homemade capacitor he used while working on the Baby. The lab coat has a burn hole — a mark of the fast-moving, hands-on practical electronics work that took place in the Manchester laboratory.

A small capacitor he had made for testing the Baby was found years later in one of his old lab coats. These small, tangible remnants bring the reality of early computing to life: three engineers working with valves, wires and cathode-ray tubes in a university laboratory, building something the world had never seen before.

From Baby to Space and Standards

Soon after the Baby succeeded, Tootill spent several months in 1949 at Ferranti helping transfer Manchester's ideas toward a full-scale commercial computer. His later career was unusually varied.

He taught computing, worked at the Royal Aircraft Establishment, contributed to information-processing terminology and standards, and became involved in European space and computing projects. From 1963 to 1969 he worked on the control centre and ground-station network for the European Space Research Organisation.

Tootill retired in 1982 but remained interested in computing. In 1998 he and Tom Kilburn took part in the Baby's 50th-anniversary celebrations using a working replica. He died on 26 October 2017, aged 95.