It's never fun writing obituaries, for obvious reasons, but it's also rewarding in that you can do your best to make sure someone gets the credit they deserve. Not that that was really a problem with Sir Maurice Wilkes, who died on Monday at the age of 97. He was widely recognised as a major figure in British computing history, mainly because he developed EDSAC, the first practical stored-program computer. He was also recognised on the world stage for coming up with the idea of microprogramming, which was widely adopted, and for seeing the potential of using new digital telephony technologies to connect computers, which led to the Cambridge Ring. He also co-authored the first book ever published on computer programming, The Preparation of Programs for an Electronic Digital Computer, which appeared in 1951.
I won't repeat too much of the story here, but Wilkes was a ham radio buff and did pioneering work on radio waves and, during World War II, radar. After being released from war service, he went back to the University of Cambridge as head of the Mathematical Laboratory, which did mathematical calculations -- a very long and arduous process, at the time. Obvously it would help if they had one of these new-fangled computers, so Wilkes built one out of valves (vacuum tubes), relays and Mercury delay lines.
He didn't know anything about Colossus at Bletchley Park: that was top secret for years. Fortunately, the Americans were not as stupid as us. They'd already built a huge valve-based computer, ENIAC, and wanted to build a stored-program computer, EDVAC, so as not to keep rewiring the thing for different jobs. Did they keep it secret? No. Wilkes got to read John von Neumann's seminal paper, First Draft of a Report on the EDVAC, and then they invited him to Philadelphia for a series of lectures given by ENIAC's designers, John Mauchly and Presper Eckert. Wilkes was able to start designing his Cambridge computer on the long voyage home on the Queen Mary.
This led to Britain having the world's first business computer in operation in 1951, ahead of the Americans, in the form of LEO (Lyons Electronic Office). That development was led by John Pinkerton -- at Wilkes's recommendation -- and it was based on EDSAC. In fact, Lyons, the tea-shop company, contributed to the cost of EDSAC's construction.
The world computer industry was soon based on what we called "von Neumann machines" while Colossus was dismantled and had its parts used for other purposes. Well, you never know when you might need a spare valve. (Don't get me started on another Cambridge man, Alan Turing, and what we did to him....)
Wilkes's Mathematical Laboratory morphed into the Cambridge Computer Lab, which led to "silicon fen" becoming a hotbed for technology start-ups, somewhat like Stanford University and Silicon Valley, though on a much smaller scale. Insofar as we have any bragging rights on the world stage, they're mostly down to Wilkes and colleagues such as Roger Needham (who also set up Microsoft Research Cambridge), David Wheeler, Andy Hopper, and many others.
Apparently the original lab had a green door on Corn Exchange Street, and this was rescued from a skip when the lab moved to its new £20 million William Gates Building (named after Bill's dad) in West Cambridge. When Wilkes retired as head of the lab in 1980, his name was put on the green door, and now the names of other major figures are added when they retire. When you go, you are literally shown the door....
Here's another nice bit of trivia. Dr David Hartley -- one of Wilkes's PhD students, who later became a colleague as Cambridge's Director of Computing Services, and his friend -- tells me that EDSAC and the old lab appeared in disguise in Fred Hoyle's excellent 1957 science fiction novel, The Black Cloud. "It's quite an accurate description of what it was like in those days," says Hartley.
Since Hoyle also worked on developing radar technology during the war, then returned to Cambridge in 1945 to teach astronomy and mathematics, he must have known the Mathematical Laboratory well.
The last time I saw Maurice was when we went round The National Museum of Computing in Bletchley Park, which I wrote up a year ago in The Guardian: Computer pioneer Sir Maurice Wilkes: vision and vacuum tubes. At 96, he was still very sharp, and he knew I was fishing for stuff to use in his obituary. I hope I did him proud. He deserved nothing less.