Geoff C. Tootill (4 March 1922 – 26 October 2017) was an electronic engineer and computer scientist who worked in the Electrical Engineering Department at the University of Manchester with Freddie Williams and Tom Kilburn developing the Manchester Baby, "the world's first wholly electronic stored-program computer". Education Tootill attended King Edward's School, Birmingham on a Classics scholarship and in 1940 gained an entrance exhibition to study Mathematics at Christ's College, Cambridge. He was forced to do the course in two years (missing Part One of the Mathematics Tripos) as his studies were cut short by World War II. After the successful operation of the Manchester Baby computer, he was awarded an MSc by the Victoria University of Manchester for his thesis on "Universal High-Speed Digital Computers: A Small-Scale Experimental Machine". Career On leaving Cambridge in 1942, Tootill managed to get assigned to work on airborne radar at the Telecommunications Research Establishment (TRE) in Malvern. Here, he went out to airfields to troubleshoot problems with the operation of radar in night fighters, designed modifications and oversaw their implementation. He later said that this was the most responsible job that he had in his life. In 1947, he was recruited by Frederic Calland Williams to join another ex-TRE colleague, Tom Kilburn, at Manchester University developing the world's first wholly electronic stored-program computer. In the UK, three projects were then underway to develop a stored program computer (in Cambridge, the NPL and Manchester) and the main technical hurdle was the memory technology. In order to test the cathode ray tube memory designed by FC Williams when it was constructed, Kilburn and Tootill designed an elementary computer, known as the "Manchester Baby". The computer could store 32 instructions or numbers using a single Cathode Ray Tube (CRT). On 21 June 1948, after months of patient work constructing and testing the Baby piece by piece, coping with the unreliable electronic components of the day, the machine finally ran a routine written by Kilburn (they didn't use the word "program" then) to find the highest proper factor of a number. In Tootill's words "And we saw the thing had done a computation". A day or two later, the Baby ran successfully for 52 minutes to find the highest proper factor of 218, which required c. 3.5m arithmetic operations. After the Baby's first operation in June 1948, Alan Turing moved to Manchester so he could use the