“Manchester and Early Computers”

Christopher P Burton

The Computer Conservation Society

• “What do you mean - ‘Computer’?”

• The first Manchester computer - “The Baby”

• Interlude - what was going on elsewhere

• The early Manchester computers

• Replicating “The Baby”

Numerical Tables

Books of tables from the 18th century

Early adding machines

Pascal 17th c.

de Colmar 1824

Charles Babbage

Mathematician

Philosopher

Genius

Analytical Engine - 1838

CONTROL mechanism

“Operations” cards a + b

c

b

a x b

e - a

e

b

STOREfor numbers

MILLarithmetic

Babbage’s Analytical Engine

The only fragment ever constructed

Arrival of Electronics

Wireless sets

Television

Radar

Colossus Codebreaking Machine

Electronic, very fast

1943, UK

Secret!

ENIAC Machine

Electronic, very fast

1945, USA

Huge

Fixed Program Computer - 1940s

STOREfor numbers

CONTROL mechanism

MILLarithmetic

Stored Program Computer - 1940s

STOREfor numbers &

instructions

CONTROL mechanism

MILLarithmetic

Instructions

What is a True Computer?

• A list of instructions to manipulate numbers (e.g. “add”, “copy”, “test” or “remember”) to be carried out one instruction after another - “a Program”

• Instructions are represented by numbers, therefore a program can modify itself

• Needs a big memory to hold the program and the numbers

Need for Electronic “Memory”

• “What do you mean - ‘Computer’?”

• The first Manchester computer - “The Baby”

• Interlude - what was going on elsewhere

• The early Manchester computers

• Replicating “The Baby”

Quest for a memory

• By 1945, several research teams were seeking a fast memory device.

• FC Williams and Tom Kilburn at Manchester University.

• During the war they had been expert radar engineers and they believed they could solve the memory problem using radar cathode ray tubes.

Freddie Williams and Tom KilburnIn 1950

Quest for a memory

• The Cathode Ray Tube Store could remember over 2000 binary digits by end of 1947

• But would it work in a computing machine?

• It needed to be tested “…in the hurly-burly of computing.”

The Need for Realistic Testing

• So they built a little computer to test their memory invention.

• Formally, it was: “The Small-Scale Experimental Machine”

• but informally: “Baby”

The Historic Event

• Monday, 21st June 1948, about 11:15

• The first time in the world that a stored-program computer worked

• The “Baby” was the World’s first Universal Computing Machine

• Nearly all modern computers are “like” that.

The Illustrated London News

The First program

From a notebook kept by Geoff Tootill

Dots & Dashes

A film fragment showing the computer probably in 1948

• “What do you mean - ‘Computer’?”

• The first Manchester computer - “The Baby”

• Interlude - what was going on elsewhere

• The early Manchester computers

• Replicating “The Baby”

Interlude - What was happening elsewhere?

• University of Cambridge 1946 - 1949

• National Physical Laboratory 1947 - 1950

• Institute for Advanced Study, Princeton -1952

• IBM - 1953

Cambridge - EDSAC

London - Pilot ACE

USA - von Neumann

IBM uses the Cathode Ray Tube store

• “What do you mean - ‘Computer’?”

• The first Manchester computer - “The Baby”

• Interlude - what was going on elsewhere

• The early Manchester computers

• Replicating “The Baby”

Early Manchester Computers

1948 -The “Baby” - The Small-Scale Experimental Machine

1949 - The University Mark 1 computer

1951 - The Ferranti Mark 1 computer

1954 - MEG

1957 - Ferranti Mercury

1953 - Transistor machine

1956 - Metropolitan Vickers MV950

1958 - Muse

1962 - Ferranti Atlas

Small-Scale Experimental Machine 1948 - Manchester

Illustrated London News photowith annotations

A newsreel film showing the enlarged computer in about June 1949

The Ferranti company gets involved

• Sir Ben Lockspeiser in 1948

• “Construct one computer to Professor Williams’s instructions”

The Ferranti Mk 1 Computer - 1951(World’s first commercially-delivered computer)

MEG - Ten times faster - 1954

Ferranti “Mercury” -1957

University Transistor Computer - 1953

Metro-Vick MV950 - 1956

University “MUSE” - 1958

University/Ferranti “ATLAS” - 1962

• “What do you mean - ‘Computer’?”

• The first Manchester computer - “The Baby”

• Interlude - what was going on elsewhere

• The early Manchester computers

• Replicating “The Baby”

The Computer Conservation Society

The Small-Scale Experimental Machine Rebuild Project

THE MUSEUMOF SCIENCE &INDUSTRY INMANCHESTER

Project Goal

“ To construct a working replica of the

Manchester UniversitySmall-Scale Experimental Machine

by Sunday, 21st June 1998

the 50th anniversary of the successful running of the world's first stored computer program

and to re-run that program. ”

SSEM - Building the Replica

• 1995 to June 1998 - 3½ years to do it all

• Fully sponsored by ICL - purchasing and use of workshops

• Acquire the obsolete parts, valves etc.

• Design studies - technical detective work

Dai Edwards’ Drawing of the Clock Circuit

Alec Robinson’s version of the Clock Circuit

Our Computer-Aided-Design version of the Clock Circuit

Illustrated London News Photo of Typewriter

The Mark 1 in 1949

Close-up of Mark 1 Typewriter

Cover of War Surplus

Catalogue

Catalogue Page with Push Button Unit

Replica of the “Baby”

Now a video of the re-building

Small-Scale Experimental MachineRebuild Project

Thanks to:

The University of Manchester for facilities and support

Our sole sponsor - ICL, West Gorton

The pioneer team for consultation and encouragement

The Museum of Science and Industry for a final home

Many individuals for information and parts

My team of CCS members for their volunteer effort