More of the inside story of the original EDSAC was revealed this week when Mrs Jean Renwick, wife of the late Bill Renwick, EDSAC’s chief engineer, came to visit. A long-held suspicion of the current EDSAC team was confirmed.
“It looks like the original,” said 90 year-old Mrs Renwick on seeing the ongoing EDSAC reconstruction, “but where is the operator’s desk?” Andrew Herbert, leader of the reconstruction project, acknowledged this omission and assured her it would be in place for the opening!
Despite failing eyesight, Mrs Renwick was clearly delighted to see the reconstructed EDSAC. She reminisced about many of the leading characters who were involved in building and running the machine at the University of Cambridge Maths Lab in the late 1940s and 1950s: Maurice and Nina Wilkes, Douglas Hartree, David and Joyce Wheeler (although she didn’t realised that they later married) and Sid Barton amongst others.
Mrs Renwick even remembers visits to EDSAC by Alan Turing and Tom Kilburn as well as others from Manchester where the Baby had been built.
Through its research, the current EDSAC reconstruction team has suspected that Bill Renwick was responsible for the day-to-day management of the original team as well as much of the detailed design and construction working to the outline set by Sir Maurice Wilkes, credited as the original designer. Mrs Renwick confirmed this: “It was very much Bill’s machine,” she said. Andrew Herbert, who was a student of Sir Maurice Wilkes in the 1970s, says that this fitted the later pattern of the way Sir Maurice worked at Cambridge: “Wilkes’ skill was conceiving new projects, getting funding for them and building a first rate team to get on with them, and mostly leaving them alone to do so!”
Mrs Renwick painted a picture of a very vibrant and friendly EDSAC community at that time. She attended the 1949 “Grand Opening” and remembers seeing paper tape read in and results typed out.
Bill Renwick left the Maths Lab in Cambridge after EDSAC had been built because he needed a higher salary to support a young family. He took a job with Plessey and rose to a senior position at Roke Manor. Mrs Renwick recalls that he found that work very demanding and the regular international travel tiring, which perhaps contributed to his sad death at the age of just 47.
Mrs Renwick was accompanied by her daughters on her visit to The National Museum of Computing. They say they have no recollection of EDSAC. They were tiny at the time, but were thrilled to see a recreation of one of their father’s accomplishments.