Making IT Work 22-23 May 2017 Proceedings British Computer Society Southampton Street, London, UK The National Museum of Computing Bletchley Park, Milton Keynes, UK © 2017 British Computer Society and The National Museum of Computing Contents Martin Campbell-Kelly Introduction 5 Doron Swade The Historical Utility of Reconstruction and Restoration 7 Andrew Herbert, Chris Burton and David Hartley The EDSAC Replica Project 22 Christopher P. Burton Maintainability and Sustainability Issues in Restored and Replicated Computer Systems 35 John K. Chilvers Curatorial Lessons from Other Operational Preservationists 44 Robert Garner Restoring and Demonstrating 1960s Vintage Computers at the Computer History Museum 54 Robert Lusch, Nicholas Hekman, and Don Manning IBM System/360 Printer Revitalization at TechWorks! 68 Johannes Blobel and Jochen Viehoff The New Public Engagement in Computer Museums and in the History of Computing Machines 81 Benjamin J. Trethowan Capturing, Restoring, and Presenting the Independent Radar Investigation System (IRIS) 91 Peter F. Linington Constructing and Testing a Replica Store for the EDSAC 97 Nicholas Enticknap Report of the TNMoC Workshop, 23 May 2017 107 Proc. Making IT Work, 22-23 May 2017 3 Proc. Making IT Work, 22-23 May 2017 4 Introduction Martin Campbell-Kelly Editor The Making IT Work conference, 22-23 May 2017, was jointly organized by the Computer Conservation Society of the British Computer Society and The National Museum of Computing, the UK’s two leading institutions for computer conservation. The conference brought together the leaders of national and international computer conservation and restoration projects, including several recipients of the Google-sponsored Tony Sale Award for Computer Conservation. The conference enabled practitioners of computer conservation to share knowledge, and newcomers to learn about their motives and achievements. The conference took place over two days. The first day consisted of a formal lecture programme held at the headquarters of the British Computer Society, Southampton Street, London, while the second day consisted of a workshop showcasing projects at The National Museum of Computing at Bletchley Park. Following a welcome from the chair of the Computer Conservation Society, David Morriss, the first day opened with three of the UK’s pre-eminent computer conservationists addressing the issues of utility, management, and sustainability. Doron Swade, well known for the construction of Babbage’s Difference Engine Number 2, talked about the purpose and value of these activities — whether Conference speakers and attendees at The National Museum of Computing workshop Proc. Making IT Work, 22-23 May 2017 5 Introduction they be conservation, restoration, or replication. Andrew Herbert, formerly managing director of Microsoft Research in Europe, described issues of project management in building a replica of the EDSAC — easily the most ambitious recent project of its kind. Chris Burton, the doyen of British computer conservators, spoke from long experience about the chequered history of sustaining projects once they have been completed. The afternoon session began with a lecture from John Chilvers, a distinguished conservation architect and heritage consultant, who set computer conservation in the wider context of the preservation of cherished objects, from historic buildings to railway locomotives. The final three lectures of the day came from overseas speakers. Robert Garner described the restoration of a pair of IBM 1401 computers at the Computer History Museum, Mountain View, California — this project won the 2014 Sale Award. Next, Nicholas Hekman of the Vintage IBM Computing Center at TechWorks! in Binghamton, New York, described the restoration of an IBM 1403-N1 line printer originally supplied with IBM System/360 computers — the project was runner-up for the 2016 Sale Award. Lastly, Johannes Blobel and Jochen Viehoff described the building of an ENIAC accumulator for visitor interaction at the Heinz Nixdorf MuseumsForum — the winner of the 2016 Sale Award. For those able to attend, the day closed with a convivial dinner at Bella Pasta on the Strand. The morning of the workshop at The National Museum of Computing was taken up with a series of presentations from project leaders of five of the museum’s major restoration and replication projects. Following a welcome from Andrew Herbert, chair of the museum trustees, Delwyn Holroyd described the restoration of a 1980s-era ICL 2966, the museum’s largest exhibit and one of the most powerful British mainframes. Next, Ben Trethowan talked about the IRIS, until recently a key component of the UK’s air traffic control infrastructure. He was followed by Phil Hayes who described the rebuilding of the Colossus, the World War II electronic code-breaking computer. Next Peter Linington described the fabrication of a nickel delay-line memory for the EDSAC replica. Lastly, Kevin Murrell described the restoration of the Harwell Dekatron Computer, the world’s oldest functioning computer. (Trethowan and Linington contributed papers describing their work to this volume.) During the afternoon attendees were given demonstrations of these five projects. So that they could see systems close-up and ask questions, workshop participants were divided into three circulating groups of comfortable size. A detailed account of the workshop by the computer journalist Nicholas Enticknap appears as the last paper in this volume. Proc. Making IT Work, 22-23 May 2017 6 The Historical Utility of Reconstruction and Restoration Doron Swade Royal Holloway, University of London Abstract During the last several decades there has been an increasing number of initiatives to reconstruct historic computing devices and machines, and to restore original specimens to working order. These projects pose many questions. To what extent is it allowable to compromise the physical integrity of the original to achieve a working system? What status does a “restored original” have as an evidentiary source? In the case of reconstructions, to what category of object do these new-old machines belong — fictitious antiques, new primary sources, public monuments? How important is physical fidelity to historical authenticity? What is the social and historical value of such projects to their makers, to the scholarly community, and to visitors who view them? This paper uses as case studies major reconstruction and restoration projects from the modern era to address a raft of questions agitated by such projects — museological, historiographical and social. Introduction During the last several decades there has been an increasing number of initiatives to reconstruct historic computing devices and machines, and to restore original specimens to working order. The starting point here is to take such activity as a given and, without making assumptions about the original motivations or how they might have been justified at the time, seek to reverse engineer the implications and issues that relate to their historical, museological and social meanings. The process is based on a suite of projects drawn from the major flagship projects of the modern era. A word about “utility” in the title of this presentation. “utility” is not here a reference exclusively to “practical usefulness”. The concept is borrowed from economic theory where Utility is thought of as that property of a thing that makes it desirable to possess (Robinson, 1964: p. 48). So we might say that the utility of a knife is its ability to cut. One might say that the utility of art is its aesthetic appeal or its ability to affect one. Here utility is unrelated to practical usefulness. Entirely untethering utility from practical usefulness, we have the case of the architectural folly. We might say that a folly has cultural utility or socio-cultural utility as a demonstration of wealth or status, but it is not that a folly is practically useful that makes it desirable to possess. It is its very uselessness that confers meaning on the notion of its utility and that allows us to talk meaningfully of the utility of a folly, however paradoxical this might sound. So what is it about reconstructions or restorations that makes them desirable? What is their value to history, to their makers, to their host organisations where these exist, and to their public and private audiences? None of the individual projects considered here are treated in any detail. Rather each is used as a placeholder for a particular aspect of utility. Many of the individual features are not unique to specific projects but are shared by many. Case Studies The pool of machines and projects to be drawn from includes: Thomas Fowler’s Ternary Calculating Machine (c. 1840) Charles Babbage’s Calculating Engines: Difference Engine No. 2 (1847-9); Analytical Engine (1836-71) Konrad Zuse’s Z3 (1941) Proc. Making IT Work, 22-23 May 2017 7 Doron Swade Manchester “Baby” (1948) Colossus (1943) ENIAC (1946) Ferranti Pegasus (1959) Each is used here as a place-holder for particular features it exemplifies. Thomas Fowler’s Ternary Calculator Thomas Fowler was an impoverished self-tutored fell-maker who designed and built out of wood a digital three-state mechanical calculator demonstrated in the 1840s and witnessed by no less than Mr. Babbage and Augustus de Morgan amongst others. The poverty of sources here is extreme: not only did the physical original not survive but there are no plans or drawings. Fowler refused to release details of the invention, even for evaluation and endorsement by George Biddell Airy, the Royal Astronomer. Fowler was an outsider to the London scientific establishment and paranoid about his invention being stolen, and with good reason. He had earlier invented a thermosiphon for circulating hot water in heating systems and his unprotected invention had been ripped off by unscrupulous exploiters with no financial advantage to Fowler — something that aggrieved him till his death. The sources for the reconstruction by Mark Glusker (Figure 1) are partial contemporary (19th century) textual accounts, one by de Morgan, and a memorial stained glass window installed circa 1870 in a church in Devon.