It Began with Babbage (18 page)

The Colossus, a prototype machine, and its production grade, the Mark II Colossus, belong to this story because they were certainly among the very first binary electronic digital computers to be built. They were, in fact, the descendents of a series of earlier machines built at Bletchley Park—the Robinson family, with Heath Robinson as the first, followed by Peter Robinson, and then Robinson & Clearn. The Colossi were followed, as the war came to an end, by other more specialized machines all with quirky names.
⁸⁷

The prototype Colossus, completed in the remarkably short period of about 11 months, became operational in December 1943.
⁸⁸
The Mark II Colossus was completed in June 1944, just 5 days before D-Day.
⁸⁹
These machines also interest us because, in Babbage's country—and Turing's—they represent England's first serious engagement with the design and construction of digital computers in the 20th century. As we will see later, they more than compensated for this tardiness by the end of the 1940s.

At the physical level, as a material artifact, the Colossus had several novel features. It was a binary machine. It used a clock pulse to time operations throughout the machine; it was a
“synchronous” machine. It used some 1500 electronic valves (the Mark II had some 2400 valves).
⁹⁰
It had a “shift register”—a register in which the binary digits could be shifted one position to the left or right in each clock step, a common feature in later digital computers. It had bistable circuits to perform counting, binary arithmetic, and, strikingly, Boolean logical operations. This latter mirrored its most original architectural feature: a capacity to perform complicated Boolean functions. Indeed, the Colossus was designed as a “Boolean calculating machine” rather than as an “ordinary number cruncher.”
⁹¹
It could also execute conditional branch operations.

Data were input through punched paper tape read by a photoelectric tape reader, whereas output was printed out on an electric typewriter.
⁹²
The only memory comprised “[e]lectronic storage registers changeable by automatically controlled sequence of operations.”
⁹³
Such automatically controlled sequence of operations—its program (although the term did not yet exist in this context)—was fed to the machine by setting switches and plugs manually.

The Colossi machines were designed as special-purpose computers, with a function to facilitate and expedite code breaking—hence, a “Boolean calculating engine.” Yet, it was sufficiently flexible “[w]ithin its own subject area” that it could be used to perform jobs that were not considered at the design stage
⁹⁴
—although this was, apparently, a forced flexibility, for it necessitated cumbersome manual intervention.
⁹⁵

What was the legacy of the Colossus for the history of computing? Because of the classified nature of its mission, the work at Bletchley Park would not be known to the public for some three decades following the end of the war.
⁹⁶
Thus, the design details of the Colossi machines could not be transmitted to other later computer projects in Britain or abroad. In this sense, this series of machines came to an evolutionary dead end.

On the other hand, the people involved left Bletchley Park after the war, carrying with them a great deal of valuable and original
knowledge
, both theoretical and experiential, into their peacetime lives. Among them, at least four would be involved with computers and computing.

Newman became a professor of pure mathematics at the University of Manchester, and Good went with him.
⁹⁷
Manchester University (as we will see) became a hugely important site for original research in computing—and remained so into the 1950s, and through the 1960s and 1970s—and Newman had no small role in establishing this tradition. Indeed, not long after taking his position in Manchester, he applied to the Royal Society for a grant to establish a “calculating machine laboratory” in the university, which was duly awarded in July 1946. Thus was initiated the Manchester tradition. Good was involved in its early years.

Turing joined, as a “scientific officer,” the newly established mathematics division in the National Physical Laboratory (NPL) in Teddington, a London suburb.
⁹⁸
The mission of
this division included “[i]nvestigation of the possible adaptation of automatic telephone equipment to scientific computers” and the “[d]evelopment of an electronic counting device suitable for rapid computing.”
⁹⁹
This appointment marked Turing's first systematic foray into building a practical version of his “universal computing machine”—the Turing machine. He conceived and developed the detailed proposal for what came to be called the NPL's ACE computers, with ACE being an acronym for
Automatic Computing Engine
.
¹⁰⁰

Michie, the classics scholar-turned-cryptanalyst, although he became a geneticist after the war, never quite forgot his interest, nurtured at Bletchley Park and shared by Turing, in chess-playing machines. In 1965, Michie was appointed professor of machine intelligence in Edinburgh University and was instrumental in making Edinburgh a leading world center in artificial intelligence.

The consequence of the Colossi projects for the future history of computer science was its people and the knowledge they held, rather than its actual machines.

  
1
. G. R. Stibitz. (1940).
Computer
. Unpublished memorandum. Later printed in B. Randell. (Ed.). (1975).
The origins of digital computers
(2nd ed., pp. 241–246). New York: Springer-Verlag.

  
2
. It is no coincidence that these were the main countries battling it out during World War II—nothing like the imperative of war to facilitate machines that expedited the mathematics of warfare.

  
3
. The literature on the evolutionary nature of creativity in technological, scientific, artistic, and literary cultures is vast—and controversial. See especially D. T. Campbell. (1960). Blind variation and selective retention in creative thought as in other knowledge processes.
Psychological Reviews, 60
, 380–400; P. Steadman (1979).
The evolution of designs
. Cambridge, UK: Cambridge University Press; G. Radnitzky & W.W. Bartley, III. (Eds.). (1987).
Evolutionary epistemology
. La Salle, IL: Open Court; G. Basalla. (1988).
The evolution of technology
. Cambridge, UK: Cambridge University Press; A. K. Sen. (1992). On the Darwinian view of progress.
London Review of Books, 14
; S. Dasgupta. (1996).
Technology and creativity
. New York: Oxford University Press; D. K. Simonton. (1999).
Origins of genius: Darwinian perspectives on creativity
. New York: Oxford University Press; S. Dasgupta. (2004). Is creativity a Darwinian process?
Creativity Research Journal, 16
, 403–413; D. K. Simonton. (2010). Creative thought as blind-variation and selective-retention: Combinational models of exceptional creativity.
Physics of Life Reviews, 7
, 190–194; S. Dasgupta. (2011). Contesting (Simonton's) blind variation, selective retention theory of creativity.
Creativity Research Journal, 23
, 166–182.

  
4
. Stibitz, op cit., p. 242.

  
5
. Ibid.

  
6
. O. Cesareo. (1946). The Relay Interpolator.
Bell Laboratories Records, 23
, 457–460. Reprinted in Randell (pp. 247–250), op cit., p. 247. (All citations to this and other articles reprinted in Randell will reference the reprint.)

  
7
. Ibid.

  
8
. Ibid., p. 239.

  
9
. R. Moreau. (1984).
The computer comes of age
(p. 29). Cambridge, MA: MIT Press.

10
. J. Juley. (1947). The Ballistic Computer.
Bell Laboratories Records, 24
, 5–9. Reprinted in Randell (pp. 251–255), op cit., p. 251.

11
. Cesareo, op cit., p. 249.

12
. Juley, op cit., p. 253.

13
. Cesareo, op cit., p. 249.

14
. Juley, op cit., p. 254.

15
. Cesareo, op cit., p. 250.

16
. Juley, op cit., p. 254.

17
. Randell, op cit., p. 239.

18
. Ibid.

19
. F. L. Alt. (1948a). A Bell Telephone Laboratories computing machine: 1.
Mathematical Tables for Automatic Computation, 3
, 1–13. Reprinted in Randell (pp. 257–270), op cit., p. 257.

20
. For more on technological complexity see G. Basalla, op cit. S. Dasgupta. (1997). Technology and complexity.
Philosophica, 59
, 113–139.

21
. Alt, op cit., p. 257.

22
. F. L. Alt. (1948b). A Bell Telephone Laboratories computing machine: II.
Mathematical Tables for Automatic Computation, 3
, 69–84. Reprinted in Randell (pp. 271–286), op cit., pp. 283–284.

23
. Alt, 1948b, op cit., p. 277.

24
. Ibid.

25
. Ibid., p. 276.

26
. Ibid.

27
. Alt, 1948a, op cit., p. 270.

28
. C. S. Boyer. (1991).
A history of mathematics
(2nd ed., Rev., p. 579). New York: Wiley.

29
. C. E. Shannon. (1940).
A symbolic analysis of relay and switching circuits
. Unpublished thesis, Department of Electrical Engineering, MIT, Cambridge, MA. For some reason, although Shannon submitted the thesis in 1937, it was approved formally in 1940.

30
. Stibitz, op cit., pp. 243–244.

31
. R. K. Richards. (1955).
Arithmetic operations in digital computers
(p. 33). Princeton, NJ: Princeton University Press.

32
. Ibid.

33
. Ibid.

34
. L. J. Comrie. (1928). On the construction of tables by interpolation.
Monthly Notices of the Royal Astronomical Society, 88
, 506–523. L. J. Comrie. (1932). The application of the Hollerith tabulating machine to Brown's tables of the moon.
Monthly Notices of the Royal Astronomical Society, 92
, 694–707.

35
. H. H. Goldstine. (1972).
The computer from Pascal to von Neumann
(p. 109). Princeton, NJ: Princeton University Press.

36
. Ibid.

37
. H.. H. Aiken. (1975). Proposed automatic calculating machine. Reprinted in Randell (pp. 191–197), op cit. (original work published 1937). Page citation to this chapter refers to the Randell reprint.

38
. Ibid., p. 192.

39
. Ibid.

40
. Ibid., pp. 192–193. Aiken also listed a fourth, more technical, mathematical requirement that we can ignore here.

41
. Ibid., p. 193.

42
. Randell, op cit., p. 187; Goldstine, op cit., p. 111.

43
. H. H. Aiken & G. M. Hopper. (1975). The Automatic Sequence Controlled Calculator [in three parts].
Electrical Engineering, 65
, 384–391, 449–454, 522–528 (original work published 1946). Reprinted in Randell (pp. 199–218), op cit., See footnote, p. 199. All page citations to these articles refer to the Randell reprint.

44
. Ibid.

45
. Ibid., p. 201
ff
.

46
. The number of significant digits indicate the range and precision of the real numbers that can be represented. For example, the value of π as a real number, 3.14285 …, can be represented to more decimal digits with an increase in the number of significant digits.

47
. Aiken & Hopper, op cit., p. 201.

48
. Moreau, op cit., p. 30.

49
. Aiken, op cit.

50
. Ibid., p. 201.

51
. Aiken & Hopper, op cit., p. 203.

52
. H. A. Simon. (1976).
Administrative behavior
(3rd ed.). New York: Free Press (original work published 1947).

53
. See, for example, H. A. Simon. (1983).
Reason in human affairs
. Oxford: Basil Blackwell; H. A. Simon. (1996).
The sciences of the artificial
(3rd ed.). Cambridge, MA: MIT Press.

54
. Ibid., 1996, op cit., pp. 27–30.

55
. A. Newell & H. A. Simon. (1972).
Human problem solving
(pp. 681, 703). Englewood-Cliffs, NJ: Prentice-Hall.

56
. Simon, 1996, op cit., pp. 111–138; S. Dasgupta. (2009).
Design theory and computer science
(pp. 32–35, 62–65). Cambridge, UK: Cambridge University Press (original work published 1991).

57
. Randell, op cit., p. 188.

58
. Aiken & Hopper, op cit., p. 203.

59
. Recall that floating-point arithmetic had been conceived by Stibitz at least as far back as 1942.

60
. Randell, op cit., p. 188.

61
. Ibid., p. 187.

62
. Ibid., p. 188.

63
. M. V. Wilkes. (1985).
Memoirs of a computer pioneer
(p. 157). Cambridge, MA: MIT Press.

64
. K. Zuse. (1975a).
Method for automatic execution of calculations with the aid of computers
. Patent application. Extract reprinted in Randell (pp. 159–166), op cit., Trans. R. Basu (original work published 1936).

65
. Ibid., p. 159.

66
. Ibid., p. 162.

67
. Ibid.

68
. Ibid.

69
. Ibid.

70
. K. Zuse. (1975b).
The outline of a computer development from mechanics to electronics
. Reprinted in Randell (pp. 171–186), op cit., p. 179 (original work published 1962 in German).

71
. Ibid.