alan Turing and
hiS conTemporarieS
Building the world’s first computers
Simon Lavington (Editor)
ALAN TURING AND HIS
CONTEMPORARIES
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ALAN TURING AND HIS
CONTEMPORARIES
Building the world’s first computers
Simon Lavington (editor)
© 2012 British Informatics Society Limited
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iv
CONTENTS
Authorsix
Acknowledgements
xi
Preface
xiii
1
THE IDEAS MEN
Science at war
The Moore School: the cradle of electronic computing
The Universal Turing Machine
Practical problems, 1945–7
The rich tapestry of projects, 1948–54
2
ACES AND DEUCES
Turing’s first computer design
Toil and trouble
Intelligence and artificial intelligence
Pilot ACE arrives at last
DEUCE and others
3
IVORY TOWERS AND TEA ROOMS
Maurice Wilkes and the Cambridge University
Mathematical Laboratory
Post-war reconstruction and the stored-program computer
A Memory for EDSAC
EDSAC, ACE and LEO
Not just EDSAC
First steps in programming
Wilkes, Wheeler and Gill
The last days of the EDSAC
1
1
3
5
8
8
11
11
13
14
17
19
21
21
22
23
24
26
28
31
31
v
Contents
4
THE MANCHESTER MACHINES
Memories are made of this …
The Baby computer
The Baby grows up
Ferranti enters the picture
A supercomputer
Programs and users
What came next?
33
33
37
38
41
43
43
45
5
MEANWHILE, IN DEEPEST HERTFORDSHIRE
The Admiralty’s secret
Innovations at Borehamwood
Swords into ploughshares
The coming of automation
47
47
50
53
55
6
ONE MAN IN A BARN
X-ray calculations
The challenge of memory
Computers for all!
The Booth multiplier
Commercial success
59
59
61
62
64
65
7
INTO THE MARKETPLACE
Out of the laboratory
Defence and the Cold War
Science and engineering
The world of commerce and business
The market grows and the manufacturers shrink
69
69
69
71
74
76
8
HINDSIGHT AND FORESIGHT: THE LEGACY OF TURING AND HIS CONTEMPORARIES
Who did what, and when?
Turing as seen by his contemporaries
Turing’s reputation by 1984
79
79
80
83
APPENDIX A: TECHNICAL COMPARISON OF FIVE EARLY
BRITISH COMPUTERS
The Manchester Small-Scale Experimental
Machine (SSEM), known as the ‘Baby’
The Cambridge EDSAC
The Ferranti Mark I’s instruction format
Instruction format for the English Electric DEUCE
vi
85
88
89
90
92
Contents
APPENDIX B: TURING AND COMPUTING: A TIMELINE
Alan Turing at NPL, 1945–8
Alan Turing at Manchester, 1948–54
95
95
98
APPENDIX C: FURTHER READING
General accounts of the period 1945–60
Chapter-specific books
105
106
106
Index
109
vii