Tommy Flowers: The Forgotten Father of Computing?

We discuss why Tommy Flowers, inventor of Colossus, is not as well-known as he ought to be

Imagine spending years of your life working on a cutting-edge new invention for the government - which incidentally you have to part-pay-for out of your own pocket - only to be told to smash it to pieces and burn all evidence. This is exactly what happened to Tommy Flowers and even now, nearly 70 years later, his first computer, Colossus, is still far more well-known than he is. 

A dapper man [YouTube] walks down an institutional corridor, turns right into a room, flicks on the light switch and shuts the door: “This was our Battersea Bridge Laboratory,” he says, making his way into the large grey and white space.

“And [this is] where we assembled the first Colossus…”

This is Tommy Flowers, father of computing, and under-celebrated hero of World War II code-breaking. In recent years the fame of Colossus has grown exponentially - a quick Amazon search reveals numerous books on the subject. Yet far less is generally known about Flowers himself, the man behind the idea, who put both his back and his cash into the project.

Unlike Turing, Flowers was happily married and lived to the ripe old age of 92. And while his life remained unencumbered by scandal it has, even now, lacked deserved recognition. “The great extent of public interest now in Turing is in part due to the drama and controversies about his life, his treatment after the war and his tragic death,” an expert, who would prefer to remain anonymous, told IDG Connect.

This has led to numerous biographies, films and other dramatic portrayals of Turing. “[Yet] there has been nothing comparable for Flowers, for whom words like ‘kindly’, ‘modest’, ‘self-effacing’ are as appropriate as ‘brilliant’ and ‘inventive’.”

Is Tommy Flowers’ story hinged in the British class system?

Flowers was born just north of Poplar, in the East End of London, in 1905, and won a scholarship to a local technical college. In the 1920s he came first in an open competition to secure the job of trainee telephone engineer. And through evening classes, he completed a degree from London University in Engineering. (Compare this to Turing’s public school, Cambridge and Princeton education).

Yet despite the limited official biography, Flowers’ life is still the subject of contradiction. In his New York Times obituary, published on 8th November 1998, Flowers’ father’s profession is listed as a man who “installed bakery machines”. While Sinclair McKay wrote in his bestselling book ‘The Secret Life of Bletchley Park’ [2011] that:  

“He was the son of a bricklayer. [And] his story is a surprising illustration of the power of education, in a period long before the term 'social mobility' became common currency.”

In 1942, Tommy Flowers was enlisted into the top secret code-breaking effort at Bletchley Park, Buckinghamshire. Although he operated at the Post Office's Dollis Hill research station in London, where Colossus was born.

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Image credit: Bill Tutte Memorial via Flickr

Interestingly there seemed to be some deliberate suggestion on McKay’s part that Flowers’ life as a code-breaker was ultimately a British class story - albeit specifically via his dealings with Gordon Welchman - one of the senior mathematicians at Bletchley Park.

"I have found him [Flowers] slow at grasping the complications of our [Bletchley Park’s code-breaking] work and his mind seems altogether too inflexible," McKay quoted Welchman before going on to add in his own words: "Yet one can also hear a trace, possibly unconscious of another sort of resistance going on; that of a Cambridge mathematics lecturer to the ideas of a partly self-educated, bumptious East Ender."

Our expert firmly refuted this, however: “I was aware of McKay’s comment, but nothing in any of my dealings with Welchman or Flowers led me to any such conclusion.”

A too self-deprecating approach to inventing?

Flowers’ contribution to computing was achieved through self-evident talent, coupled with relentless hard work and dedication. Later, he wrote of his team: “It was a feat made possible by the absolute priority they gave... many did nothing but work, sleep and eat for weeks and months on end except for one half day a week..."

This was work that Flowers famously described as a ''string-and-sealing-wax affair”. Yet however makeshift those early inventions were, many of the materials were supplied by Flowers himself. Post-war he was awarded £1000 [$1585] by the government by way of compensation – this sum failed to cover his investment.  

“At the time I had no thought or knowledge of computers in the modern sense,” he wrote retrospectively “and had never heard the term used except to describe somebody who did calculations on a desk machine.''

Today there is little doubt about the impact this had on World War II and the development of computing.  Colossus successfully decoded long messages to and from Hitler himself. These covered issues of strategy and had an immediate effect on the D-day decision making. And stood completely at odds with the typically low-level information contained in the famous Enigma traffic.

Flowers may have been awarded Order of the British Empire. Yet as the BBC put it: "The secrecy surrounding Colossus meant Mr Flowers' position in the history of computers has been overlooked."

As contemporaries explained in a short film made by Google, once war was over the orders were to smash everything to pieces. According to these testimonials some Colossus machines were even dumped down coal mines. This was extremely galling for the people who had worked hard, for years, creating and nurturing these machines.

It also pushed back the development of computing. “Tommy Flowers held various master documents in a safe concerned with Colossus and he had been instructed that these were to be destroyed,” described one individual. “And he went down to the workshop and destroyed them. Put them on the fire. That was the end of them.”

The work at Bletchley Park was in fact so top secret that veterans couldn’t even tell their own families. Flowers’ son Kenneth said that growing up he didn’t know what his father had done during the war: "I knew it was something scientific or technical, but I didn't learn about Colossus until the story became public in the 1970s."

Why has Flowers been largely unrecognised?

Our expert believes, aside from the enforced secrecy, part of the reason Flowers is less well known than he ought to be, is that while many people are familiar with the German Enigma machines so famously associated with Alan Turing, the same is not true of the Lorenz machines, which Colossus broke.

“Very few are known to exist - I can think of the locations of a handful at most, all in museums, so it has not become a target of collectors, and its visual appearance is not familiar. Explaining how it worked is challenging.”

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Image credit: Wonders and Marvels via Flickr

Once the secret of Bletchley Park was leaked in the 1970s, “The Government was also in no hurry to explain how much of Bletchley Park's great impact was due to the breaking of Enigma, and how much due to Colossus,” continued our expert. “Leave alone how long they went on using two Colossus machines at GCHQ after the war.”

After the war, as everything still had to remain so hush-hush, Flowers was forced to abandon any hopes he may have had of pursuing his computing research and instead returned to his electronics role at the Post Office. He remained there until 1964 pioneering electronic exchanges and eventually retired in 1969.

When his war work eventually became public six years later, our expert told us, there didn’t seem to be “much enthusiasm amongst those [who] could have provided good assessments” of his pre and post-war career. This meant for the most part his achievements remained unknown. “Thus public attention was almost of necessity focussed almost entirely on his Colossus efforts.”

“In more recent years BT [formerly part of the Post Office] has belatedly realised the importance (and publicity value) of what was done in their Dollis Hill Labs,” he continued. “And now makes an absolutely justified fuss about Flowers and Colossus, and Flowers' wider career.” This included the release of an official bronze bust of Flowers last December.

“It is evident that public knowledge of Colossus and Tommy Flowers has grown considerably, especially in the last 10 or so years, and is, I'm sure, going to continue to grow, indeed I expect quite considerably,” our expert concluded.

“The sad thing is that the publicity, indeed fame, came too late to help him in his post-war career.”


Kathryn Cave is Editor at IDG Connect