A pioneering piece of first-generation computer hardware was re-introduced to the public today. Almost 63 years after it made its debut at a trade show, the prototype of Britain's first mass-produced business computer is now on display at The National Museum of Computing (TNMOC) at Bletchley Park in Milton Keynes, about 50 miles north of London. The Hollerith Electronic Computer (HEC-1) was Britain's most commercially successful early computer and the first to be installed in many countries, such as India, New Zealand, and those in East Africa.

The HEC-1 was the first of the HEC series and is on loan from the Birmingham Museums Collection Centre, where it was recently discovered in storage. Its design is based on the work of Professor Andrew Booth of Birkbeck College, London. Originally a crystallographer, Booth started working with computers as a way of handling the complex calculations needed for his work.

Working alone and on a shoestring budget, Booth developed a computer called the All Purpose Electronic Computer (APEC). In an interview with the BBC, computer scientist turned computer conservationist Dr Robert Johnson said that Booth's pioneering work produced a number of firsts and near firsts. For example, he wrote a multiplier algorithm that is now found in most smartphones. In addition, Booth almost invented the floppy disc, but the magnetic-dust impregnated paper he used couldn't stand up to the high speeds needed, so he settled for inventing the first drum memory.

Dr Raymond Bird with the HEC in 1953(Credit: TNMOC)

In 1951, Booth struck a deal with the British Tabulating Machine Company (BTM), where there was concern about the growing competition to the company's punch-card tabulating system from the new digital computers. He agreed to provide BTM with his technology if it would give him input and printing systems for it.

The result was known the HEC, with electronics expert Dr Raymond Bird was commissioned to turn Booth's APEC into a practical commercial computer.

"Previously I had only worked with analogue technologies and I was mesmerised by seeing this digital door opening before me," said Bird. "It was my job to get something working. I did the things that Booth thought were trivial – I engineered it! Unknown to me at the time, the people working in the room next to me were the engineers who had made the wartime code-breaking Bombe machine designed by Alan Turing and deployed at Bletchley Park. In the early 1950s they were continuing to develop machines for BTM."

By late 1951 the prototype HEC-1 was ready to run its first program. It wasn't very big by 1950s standards. It measured only 1.5 x 3 x 0.5 m (5 x 4.2 x 1.6 ft) and was powered by about 1,000 radio valves. Along with its two-kilobyte magnetic memory drum, it had a punched-card input and a printer or punch-card output.

In June 1953, the pre-production HEC-2 was put on display at the Business Efficiency Exhibition at Olympia in London.

"We worked throughout the night at Olympia to have the HEC ready – keeping a friendly eye on our competitors, Power Samas, who were working just as hard a few stands away," says Bird. "They were preparing an electronic multiplier and printer, but when they saw what we had, they had fear in their eyes. Our demonstration of the noughts and crosses game was a great success in showing the potential power of computers. This was probably the first time that a computer had gone on public display in Britain."

BTM then decided to focus development on an affordable machine for businesses rather than scientists. The result was the HEC-2M, which later became the HEC-4 and sold over 100 units by 1962. In 1959, BTM merged with ICT and the HEC-4 became the ICT 1200 series,

The HEC-1 is on display in the TNOMC's First Generation Gallery along with the reconstructed 1949 EDSAC computer and the original 1951 Harwell Dekatron / WITCH computer.

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