World's oldest working computer to be rebooted

Money pending, a classic of the early computing age will get a new lease on life.

The Harwell computer will become the oldest functioning electronic stored program device in the world if Bletchley Park boffins can raise the funds to get it fixed.

The giant rack of vacuum tubes is being taken out of storage at Wolverhampton University where it has been gathering dust since 1973. The amazing thing is that, until then, the Harwell - or the WITCH (Wolverhampton Instrument for Teaching Computing from Harwell) as it was known at the time - was still being used to teach computing science to students. Its new home will be at the National Museum of Computing (TNMOC) at Bletchley Park, wartime home of the Enigma Machine codebreakers.

The machine was designed in 1949 and was intended to take some of the slog out of scientific calculations that previously were being done using the kind of clackety-clackety-kerchunk mechanical calculators you see in old movies. The team of human calculators involved apparently were so bored with the whole process that they were making mistakes and having to start all over again.

The intention was to automate the work simply, reliably and in a way that would allow the muddled mathematicians to slope off down the pub while the machine did all the boring work.

It's lucky they weren't in any kind of the rush as the machine didn't manage its first bit of number crunching until two years later in 1951.

TNMOC spokesboffin Kevin Murrell told us, "The machine was a relay-based computer using 900 Dekatron gas-filled tubes that could each hold a single digit in memory - similar to RAM in a modern computer - and paper tape for both input and program storage.

"Its promises for reliability over speed were certainly met - it was definitely the tortoise in the tortoise and the hare fable. In a race with a human mathematician using a mechanical calculator, the human kept pace for 30 minutes, but then had to retire exhausted as the machine carried on remorselessly. The machine once ran for ten days unattended over a Christmas and New Year holiday period."

The machine will be restored by volunteers at the museum, but the organisation is desperate for funds and as a result is selling 25 'shares' in the project at £4,500 a pop to altruistic individuals and companies like Insight Software, which is the first to pony up. Don't expect a return on your investment though. The warm fuzzy feeling you get knowing you have helped to preserve an essential slice of computing history will have to be enough.

"The TNMOC team of engineers are (sic) eager to start the restoration work," Kevin Murrell told us. "They have proved their skills, perseverance and sheer ingenuity in many projects and, for most of them, this will be the toughest project yet. It's the computing equivalent of the raising of the Mary Rose and they are up to challenge!"

We just hope the Harwell doesn't suffer from silicon envy as it will be housed alongside a rebuild of Colossus II, the world's first electronic computer.