What the DEUCE? Scotland's first computer

In 1957, the University of Glasgow established Scotland's first Computer Laboratory, and the initial Director of Computing was Dennis Gilles.   Gilles advised the University to order its first machine - a DEUCE - which was commissioned in 1957, installed in 1958 and ran for seven years.    This was the first electric computer at a Scottish University.

DEUCE Mercury Delay Line

The origin of the DEUCE

Alan TuringAfter his code breaking heroics in World War II,  Alan Turing joined the National Physical Lab (NPL) where he set about designing a general purpose electronic computer.  The machine was called the Automatic Computing Engine (ACE).  Although Turing left NPL before the ACE was built, the project was successful.  The pilot ACE ran its first program in 1950.

Soon after, the English Electric Company produced an upgraded machine called the Digital Electronic Universal Computing Engine (DEUCE).   The retail price was around £50k.

The English Electric Company was merged with other British computer manufacturers in the 1960s to form International Computers Limited (ICL) which was taken over by Fujitsu in the1990s.

DEUCE technical specification


Instructions included integer arithmetic for various word lengths, data transfer and discrimination for conditional tests.   The clock speed was 1MHz (~1,000 times slower than your smartphone), but due to the serial nature of the delay lines a single memory access would take 32 microseconds.


Data was stored in mercury delay lines.   Each of the 12 lines could hold 32 words of 32 bits each.  The total RAM was just over 1 Kb ~one million times smaller than your smartphone.

Power consumption

The machine drew 9kw of power which is around 12 washing machines (~5,000 times more than your smartphone).


The machine occupied 9 square metres of floor space.  The University DEUCE was installed in the basement of the Joseph Black Building.



Undergraduate students have implemented a Java simulator for the DEUCE machine. This was built using a hardware model-sized replica of the front panel using a Raspberry Pi and lots of LEDs which was on display in the foyer of Sir Alwyn Williams Building in Summer 2017.