||Technology in Australia 1788-1988
Table of Contents
I Part 1: Communications
III Part 2: Early Australian Computers And Computing
i Instruments and calculators
ii The transition to the computer, 1945 to 1951
iii The first computers, 1951 to 1956
iv Concentration on large-scale systems, 1958 to 1963
v Software and microelectronics, after 1965
vi Industry, education and the computing fraternity
The transition to the computer, 1945 to 1951 (continued)Pearcey had spent the period 1940-45 in the UK engaged on mathematical aspects of development of short wave and microwave radar which required large scale computation and the use of analogue and digital aids. He worked with D. R. Hartree, with whom he had discussed the possibility of fast digital computation. The work of Turing and the Bletchley Park projects were, of course, not known. In travelling to Australia late in 1945, Pearcey visited the Howard Aiken at Harvard and saw the Automatic Sequence Controlled Calculator (ASCC) there but not the Bell relay machines or the ENIAC, which was then under trial. Beard had spent the war in RP after graduating in engineering at the University of Sydney and was experienced in practical vacuum tube-based pulse techniques.
The ideas for, and development of, the Mk 1 were separate from the mainstream of progress overseas some 10,000 miles away. It was known from the ASCC experience that use of paper tape for providing instructions for sequential execution at run time was too slow, that data and instructions had to be available for execution and operation at comparable speeds. This required a means of holding and readily accessing both data and instructions. Also, decoding and encoding processes and a scheme for specifying and sequencing execution of sets of instructions, i.e. a programming technique, had to be devised. Pearcey was aware, however, of the neurological work of W. S. McCulloch and W. Pitts (1943) and of T. Gold's work at Haslemere on the use of acoustic delay lines for radar signal enhancement and the possibility of this as a storage medium.
The Mk 1 was a 'programmer's machine, structured for engineering simplicity and economy and flexibility since the main objective was the development of programming techniques leading later to breadth of application. The machine was entirely serial in operation, with 20 bits (binary digits) per instruction/number (word) and performed about 500, later 1000, operations per second using a mercury acoustic delay store of up to 1024 words. Extensions included an additional 4096 words magnetic drum storage. Input and output, initially via punched cards was changed to 12 hole and standard 5 hole paper tape. The machine was first demonstrated publicly in August 1951 and was used for programming studies, computations for radioastronomy and cloud physics for RP researches and computations for various CSIRO Divisions, engineering projects, various university and government departments and agencies in Sydney until mid-1956 when it was transferred to the University of Melbourne. Late in 1948 Myers visited some of the UK computer projects at CSIR'S request and, in 1949, advised that work on development of computing machinery should be confined to components only -at least until a cheap and reliable directly accessible storage medium became available. This was to affect what followed, particularly in respect of the Mk 1.
This period ended with the first Conference on Automatic Computing Machines, held in August 1951 at the Department of Electrical Engineering and sponsored by that Department and CSIRO. Thirteen papers were given to 160 participants. The conference was accompanied by an exhibition demonstrating use in scientific computation of various commercially available calculating and accounting machines. The Mk 1 computer and Hollerith (BTM) punched card system at RP and the electromechanical differential analyser at the Department of Electrical Engineering were included.
Organisations in Australian Science at Work - Australian Bureau of Census and Statistics; University of Adelaide. Department of Electrical Engineering; University of Melbourne. Department of Electrical Engineering
People in Bright Sparcs - Beard, M.; Bowden, A. T; Green, J. R.; Myers, D. M.; Pearcey, T
© 1988 Print Edition pages 616 - 617, Online Edition 2000
Published by Australian Science and Technology Heritage Centre, using the Web Academic Resource Publisher