Colossus tools of the trade

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Seventy-five years after the first Colossus was under construction, the original tools and tool bag of an engineer who maintained the code-breaking Colossus computers are on display alongside the working rebuild of the computer at The National Museum of Computing.

The family of the late Henry (John) Cane, a wartime General Post Office engineer, has donated his 1940s tool case and twenty tools. John was a member of one of the dedicated teams that built and kept the Colossus computers running almost continuously at Bletchley Park from February 1944 until the end of the Second World War.

Andrew Herbert, chair of TNMOC, said “The impact of this new technology changed history. By accelerating the deciphering of German High Command’s top-secret Lorenz-encrypted messages, the Colossus machines were instrumental in shortening the war by an estimated two years, thereby saving countless thousands of lives. And the equipment marked the earliest stages in the development of our digital world.”

In December 1943, the first Colossus was being built and tested by Tommy Flowers and his ‘band of brothers’ at Dollis Hill, the laboratories of the General Post Office (now BT) in London. Flowers had taken the bold and unprecedented step of creating a machine with 1500 valves that could be programmed to run the code-breaking algorithms devised by the brilliant mathematician Bill Tutte.

The first Colossus was being built in December 1943 and is thought to have its first successful trial run at Dollis Hill on 8 December 1943. In December 1943 or perhaps January 1944, it was moved to Bletchley Park where it was reassembled and broke its first Lorenz message on 5 February 1944. These encrypted messages which previously might take weeks to decipher by hand could then be broken in a few hours.

Phil Hayes, chief engineer who maintains the Colossus painstakingly rebuilt by the late Tony Sale and his team at TNMOC, said, “I use tools like John Cane’s almost every today to keep the Colossus rebuild running, but these originals are very precious. Although they were designed for use in Strowger analogue telephone exchanges, they became critical to the war effort because Tommy Flowers, a telephone engineer by training, built Colossus mostly with telecommunications components -- that was the technology available to him.”

“My favourite is a specialist 28-inch long screwdriver with a sleeve that is used on the plug boards and lamp strips. We are very grateful to the Cane family for their donation.”

By the end of the war, ten Colossus machines were kept running around the clock by teams of engineers, using tools like those of John Cane. Shifts of young Wrens would operate the Colossus machines and pass the Lorenz wheel settings discovered to codebreakers who could then decipher the top-secret enemy messages. In 2019, the museum plans to hold several events to mark the 75th anniversary of Colossus.

On 5 February 2019, it will be 75 years since Colossus attacking its first Lorenz message. In April 2019, the museum plans to celebrate the completion of reconstruction of the Heath Robinson machine, the predecessor and inspiration of Colossus. The month of may marks the 75th anniversary of the arrival of the second phase of Colossus machines (Colossus Mark IIs) which arrived in time to provide vital intelligence about enemy plans at the time of the D-Day landings.

About The National Museum of Computing

The National Museum of Computing, located on Bletchley Park in Block H, one of England’s ‘irreplaceable places’, is an independent charity housing the world's largest collection of functional historic computers, including reconstructions of the wartime code-breaking Colossus and the Bombe, and the WITCH, the world's oldest working digital computer. The Museum enables visitors to follow the development of computing from the ultra-secret pioneering efforts of the 1940s through the large systems and mainframes of the 1950s, 60s and 70s, and the rise of personal computing in the 1980s and beyond.

The Museum runs a highly successful Learning Programme for schools and colleges and promotes introductions to computer coding amongst young people to inspire the next generation of computer scientists and engineers.

Sponsors of the Museum have included Bletchley Park Science and Innovation Centre, Fujitsu,, Paessler, Sophos, Lenovo, Bloomberg, Ocado Technology, Ceravision, CreateOnline, 4Links, Google UK, IBM, NPL, HP Labs, FUZE and BCS.

The whole Museum is open to the public from 12 noon - 5 pm on Thursdays, Saturdays and Sundays, spring and summer Bank Holidays. During long school holidays, there are additional opening days. The Colossus and Tunny galleries are open daily. Public and private Guided Tours are available and bookable online – see the website for details. Educational and corporate group visits are available by prior arrangement.

Please note: for three months from 30 November 2018, the First Generation Gallery and the Mainframes Gallery will be closed because of a roof refurbishment.

For more information, see and follow @tnmoc on Twitter and The National Museum of Computing on Facebook.

Media Contacts

Stephen Fleming, Palam Communications, for The National Museum of Computing
01635 299116

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