ATLAS@50 Then and now Science & Technology Facilities Council The origins of Atlas In the years following the Second World War, there was huge interest in nuclear physics technologies both for civilian nuclear energy research and for military nuclear weapons. These technologies required ever-increasing amounts of computer power to analyse data and, more importantly, to perform simulations far more safely than would be possible in a laboratory. By 1958, 75% of Britain’s R&D computer power was provided by the Atomic Energy Authority (UKAEA) at Aldermaston (using an American IBM 704), Risley, Winfrith and Harwell (each using a British Ferranti Mercury). These were however what we would now call The advisory panel for the super-computer single-user systems, capable of running only included Freddy Williams (a pioneer in radar and Foreword one program at a time, so were essentially very computer technology) from Victoria University large desktop calculators. Indeed, the name of Manchester, Maurice Wilkes (designer of It is now known as Rutherford Appleton Laboratory buildings R26 and R27, but over “computer” referred to the human operator; EDSAC, the Electronic Delay Storage Automatic its 50+ year history, the Atlas Computer Laboratory in the parish of Chilton has been the machinery itself was known as an Calculator) from Cambridge, Albert Uttley of the “automatic calculating machine.” RRE (Royal Radar Establishment), and Ted Cooke- part of many seminal moments in computing history. Yarborough (designer of the Dekatron and CADET British manufacturers of automatic calculating computers) from AERE Harwell; Christopher Over its 50+ year history it has also housed It was cleaned and restored as far as we could, machines were doing well until IBM announced Strachey (a pioneer in programming language many mainframe and super-computers including and took pride of place at an event held to that their first transistorised computer was to design) was in charge of design. the Ferranti Atlas 1, a Sigma 2, a PDP15, an ICL celebrate the 50th anniversary of its inauguration. be launched in a couple of years’ time in 1961. 1906A, two IBM 360/195s, an Atlas 10, and It now makes occasional appearances at other This was the model 7030, known as STRETCH, three Crays (an X-MP, a Y-MP and a J90). These events held at Rutherford Appleton Laboratory. which would cost $13.5M and (according to the machines have all been decommissioned now, marketing hype) be two orders of magnitude but the consoles of the Atlas 1, one of the IBM This publication attempts to capture something faster than their current IBM 704 model. (As it 360/195s and half the Cray X-MP have been about what made the Ferranti Atlas 1 super- turned out, the performance of STRETCH was preserved together with a physical archive of computer, the building which housed it, and disappointingly only six times faster, and the papers, manuals and other artefacts, and a virtual the people who worked on it, such a significant price was dropped to $7.78M.) part of British computing history. archive known as the Chilton Computing web site. Britain was now in danger of losing its competitiveness so at a meeting in January 1957, Ferranti Ltd was a family-run British electrical engineering The console of the Atlas computer was and equipment firm established in 1885, with its HQ rediscovered in July 2014; it had been languishing Lord Halsbury, Director of the National Research in Manchester. It specialised in building high voltage in storage for so long that even the paperwork Development Corporation (NRDC), announced an transformers and other equipment for the electrical grid, in domestic “brown goods” such as televisions, radios, had been forgotten. ambitious £1M project to develop a new British high-performance computer – a super-computer and electric clocks, and was a major developer of radar systems, defence electronics and avionics during the to rival STRETCH. Second World War. In the 1940s and 1950s, Ferranti collaborated with various university research groups to He had some doubts however: “Are we strong develop a series of computers including the Ferranti Mark enough to compete? Ought we to try? Could we 1, Pegasus, Orion, and a solid state version of the Mark 1 afford not to?” known as Mercury. 2 3 The NRDC had not given up however and awarded A second Atlas was shared between British a grant of £300K to both Ferranti (with Tom Petroleum (BP) and London University, managed Kilburn as lead designer) and EMI (with Christopher by the University of London Atlas Computing Strachey as lead designer) to pursue the design of Service (ULACS, or ACS for short). two super-computers. Clearly there was a certain amount of professional rivalry, but in the end the The third and largest Atlas was installed in the EMI project did not happen, and the Ferranti one purpose-built Atlas Computer Laboratory in was in progress anyway. Christopher Strachey Berkshire (now Oxfordshire), located between was an enthusiastic self-taught designer, but he AERE Harwell and the National Institute for was not an engineer as Tom Kilburn was; he also Research in Nuclear Science (NIRNS) Rutherford had what Maurice Wilkes described as “strong Laboratory. personal views” which could make working with In 1972, it was estimated that the Atlas him difficult. development project had cost £2M, of which £50K had been contributed by the University. It Ceremonial inauguration of the first Atlas computer, In Manchester, on Friday 7th December 1962, the Manchester, 7th December 1962. first production Atlas computer was ceremonially had been a long and sometimes tortuous project Professor Tom Kilburn at the which Sebastian de Ferranti said should have been Atlas Engineer’s console, Manchester. Pictured are Sir John Cockcroft (seated), switched on by Sir John Cockcroft. Sebastian de Ferranti andTom Kilburn. called BISON (Built In Spite of NRDC). The plan was that development contracts would Kilburn was asked to redesign part of the system. be placed with universities and government When he realised that he had not been appointed departments, and various manufacturing lead engineer on a project involving something he companies including EMI, English Electric and had designed however, Tom Kilburn backed out Ferranti were approached to build the machine. altogether. The longer-term project also failed to Their responses were mixed. English Electric get off the ground. were uninterested; EMI and Ferranti were more enthusiastic, but they and AERE Harwell had A few months later, Ferranti and Tom Kilburn’s concerns about the proposed design, about the team at Manchester made the decision to take management of the project, the expense, and the matters into their own hands and to build a large financial viability of the end result. scientific machine based largely on MUSE. This project was supported by John Cockcroft, Director Frustrated by the lack of progress, the Second of AERE Harwell, but unsurprisingly NRDC were Harwell Computer Conference was held in less enthusiastic as they felt it was incompatible February 1958 (the first was held in April 1957) with their aims. It was clear that the need for a between AERE Harwell, NRDC, RRE, the National super-computer – *any* super-computer – was Physical Laboratory (NPL), the Ministry of Supply becoming more pressing, that the Manchester (later the Ministry of Defence), and the universities project was making significant progress, and that of Cambridge and Oxford. Two recommendations the NRDC was getting nowhere. were made to try and get the super-computer project moving again: a short-term project to In October 1958 it was announced that the assess MUSE (the MicroSecond Engine designed Manchester machine designed by Tom Kilburn was by Professor Tom Kilburn at the Department of to be called Atlas, and would be built by Ferranti’s Electrical Engineering at Victoria University of Computer Division headed by Peter Hall in a Manchester), and a longer-term project to develop former steam locomotive factory in West Gorton. new components and techniques. (The premises were spacious, although soot in the electrical components was a constant problem.) These ideas also met with a mixed response. Although MUSE was thought to be a good basis for further development, its performance fell short of that required for the super-computer so Tom The London Atlas being Commissioned at Ferranti, August 1963. 4 5 The Ferranti Atlas computer at Chilton The hardware The third and largest Atlas computer was ordered by UKAEA on 22nd September Atlas was a 48-bit word machine, with 48K of core store arranged in six pairs of 1961. It cost £3.1M, and Ferranti were understandably so pleased that they hosted stacks, 128 half-words of B store, 8K words of Fixed Store (ROM), 1K words of a celebratory dinner at The Savoy. Supervisor working store, four drums each of 24K words drum store, 16 Ampex TM2 magnetic tape drives, two IBM magnetic tape drives, and 16 Data Products The machine took three years to construct and was finally delivered to its new home in June 1964. It model 5045 file disks each 16.8M word capacity. was considered so valuable that it was transported from Manchester using 19 separate trucks so that if there was an accident only one piece would be lost. It was up-and-running just four months later Core store: Core store consisted of Bakelite frames approximately 20cm square containing a 68x68 grid of thin (albeit with an “at risk” service), and by February wires with a (magnetic) ferrite doughnut-shaped core at 1966 it was in full operation 24/7 with three shifts each junction. Each core represented one bit and could be of Operators plus engineering support. magnetised clockwise or anticlockwise to indicate a binary 0 or 1.