Colossus, the world's first electronic computer, had a single purpose: to help decipher the Lorenz-encrypted (Tunny) messages between Hitler and his generals during World War II.
The Colossus Gallery houses the rebuild of Colossus and tells that remarkable story.
Colossus reduced the time to work out the Lorenz chi-wheel settings and enabled more messages to be deciphered and the whole code-breaking operation to be accelerated. The information gleaned from the decrypted messages is widely acknowledged to have shortened the war by many months, saving tens of thousands of lives.
The cipher text was input via paper tape and the 2500 valves of Colossus would find the Lorenz machine chi-wheel settings.
By the end of the war, 63 million characters of high-grade German communications had been decrypted by 550 people helped by the ten Colossus computers.
Not until 1975 when the first information about Colossus was declassified could the story begin to be told.
In 1992, Tony Sale and his team began the ambitious task of rebuilding a working Colossus. They succeeded and in 2007 it was tested in the global Colossus Cipher Challenge. Once again Colossus was able to crack the Lorenz code (in 3.5 hours), but was beaten in the race by Joachim Schueth, a professional computer software engineer, who wrote special software for his PC to break the ciphertext in just 46 seconds!
In 2012, a major fundraising campaign, led by TNMOC trustee Tim Reynolds, was launched to convert the old Colossus workshop room into a brand new Gallery. Much work has still to be done to complete perhaps the world's most exciting computing exhibit, but already Colossus is viewable by the public as never before and is set to inspire future generations of engineers and computer scientists.
The Colossus Computer
Tommy Flowers spent eleven months designing and building Colossus at the Post Office Research Station, Dollis Hill, in North West London. After a functional test, Colossus Mk 1 was delivered to Bletchley Park in late December 1943 / January 1944, was assembled there by Harry Fensom and Don Horwood, and was working in early February 1944.
Colossus was the first of the electronic digital machines with programmability, albeit limited in modern terms. The notion of a computer as a general purpose machine - that is, as more than a calculator devoted to solving difficult but specific problems - would not become prominent for several years.
Colossus was preceded by several computers, many of them being a first in some category. Colossus, however, was the first that was digital, programmable, and electronic. The first fully programmable digital electronic computer capable of running a stored program was still some way off - the 1948 Manchester Small Scale Experimental Machine.
The use to which the Colossi were put was of the highest secrecy, and Colossus itself was highly secret, and remained so for many years after the War. Colossus was not included in the history of computing hardware for decades, and Flowers and his associates were deprived of the recognition they were due for many years.
It has taken nearly fifteen years to rebuild the Mark II Colossus computer in the same position as Colossus 9 originally occupied in Block H. Using only scraps of diagrams, old pictures and half-forgotten memories Tony Sale and his team re-created this fantastic world-first for Britain and set the benchmark for computer conservation.
For further information about how the Colossus story surfaced, and more details about the Colossus rebuild project by the late Tony sale, click on the following links:
E.R.N.I.E (Electronic Random Number Indicator Equipment)
ERNIE was a hardware random number generator created to find winners each month for the premium bond prize draw. A Premium Bond is a lottery bond issued by the United Kingdom government's National Savings and Investments agency. The bonds are entered in a regular prize draw each month and can win various amounts up to the current top prize of £1,000,000.
The first ERNIE was built in 1956 by the Post Office Research Station at Dollis Hill. The team that built it included some of the same team of engineers who built Colossus, the world's first electronic computer. ERNIE was installed at Lytham St.Annes, a coastal town in Lancashire, England, just south of Blackpool.
ERNIE was designed by Harry Fensom, who worked in the department run by Tommy Flowers, the designer of Colossus, and was built by a team lead by Sidney Broadhurst.
Before ERNIE 1 could be built, a test of the components to be used was required. So a small test machine was built and later dubbed "Little ERNIE". As part of that process, a demonstration unit was also built to show how the random number generation was calculated.
As part of the Harry Fensom archive, graciously donated to TNMOC, we have 2 documents that relate directly to ERNIE.
The first is a general description of the system, signed and dated by Harry Fensom, and possibly written by him, although that cannot be confirmed.
ERNIE - General Description (PDF)
The second is an article describing the technology used in ERNIE and some of the techniques used to ensure the randomness of the machine was maintained.
ERNIE - Technology Description (PDF)
Reconstructing the demonstrator
To celebrate the 60th anniversary of the award of the first Premium Bond prize (then £1,000), there was an evening event in 2017 at The National Museum of Computing, featuring a reconstruction of ERNIE’s ancestor that demonstrated to an enthralled 1950s public how electronic noise could be used to generate random numbers for the prize draw.
The unit you see in the Colossus gallery is a reconstruction of the demonstration unit and was built by TNMOC in 2017.
Colossus Rebuild chief engineer, Phil Hayes, explains ERNIE
The power of Premium Bonds: ERNIE 5 taking a quantum leap
Since ERNIE 1 in 1956, there have been 4 further versions, with the latest one, ERNIE 5, introduced in March 2019 taking a different approach to generating random numbers.
All previous ERNIEs have used thermal noise to produce random numbers, however ERNIE 5 is powered by quantum technology, the ability to produce random numbers through light.
This new technology, developed by ID Quantique (IDQ), has allowed ERNIE to produce enough random numbers (approx 3 Million) for each months draw in just 12 minutes, far superior to the 9 hours that ERNIE 4 took towards the end of its random number generating career
For the launch of the fifth ERNIE, TNMOC volunteer Martin Gillow created a Virtual ERNIE. Why not try it for yourself…
