[SIGCIS-Members] Percy Ludgate and Konrad Zuse

Brian Randell brian.randell at newcastle.ac.uk
Sat Nov 26 14:58:15 PST 2022


I assumed that after the recent celebration in Dublin of the centenary of Percy Ludgate's death (https://www.scss.tcd.ie/SCSSTreasuresCatalog/literature/TCD-SCSS-V.20221015.001/TCD-SCSS-V.20221015.001.pdf), when I drew the short straw and was the member of Brian Coghlan's team investigating Ludgate who was tasked with speaking, I would be able to reduce greatly the time I was spending on Ludgate.

Instead, the day before the ceremony, we were alerted by Ralf Buelow to his Heinz Nixdorf MuseumsForum blog post (https://blog.hnf.de/percy-ludgate-der-unbekannte-computerpionier/) which revealed to us that Ludgate's work on an "Analytical Machine" had been used, in 1960, to attack Konrad Zuse's attempts at patenting the concept of program-controlled digital computer - work that was one of the reasons that Zuse was denied a patent. This attack was by the Triumph office machinery company, citing Ludgate's 1909 paper on his Analytical Machine. The question which intrigues us is how did Triumph and its patent attorney find out about the little-known Irish inventor? (Konrad Zuse later claimed that the company had received help from IBM - we have established that Triumph's patent attorney also worked for IBM.)

Since we received this blog post we have been investigating records of Zuse's patent efforts, and trying to find out how news of Ludgate reached Triumph. In so doing we have found that there was significantly more awareness in the USA in the 1930s of Ludgate's work than we had suspected - in particular that a full reference to his 1909 paper was included a 1938 bibliography by Irwen Travis, a colleague of John Mauchly at the Moore School, who in 1946 gave a talk on the history of computers at the famous Moore School Lectures.

One of the major sources we would like to be able to search are the voluminous records of the ENIAC patent litigation (1967-1973), since at the trial a number of the witnesses testified regarding their careers and knowledge of early computer developments, as well as any involvement in ENIAC. These records are at the Charles Babbage Institute, the University of Pennsylvania, and the Computer History Museum. However, these very important records are not fully indexed, and not available online, leave alone as searchable PDFs. (If only a project to generate such an online resource could be resourced and undertaken!)

We would be pleased to hear from anyone who has detailed knowledge of these ENIAC records, and could guide our efforts to check whether they contain any references to Ludgate's work. 

Indeed, more generally, we would welcome any information leading to the discovery of other pre-1960 references to Ludgate, beyond the one we are aware of in Maurice Wilkes' book Automatic Digital Computers (Methuen, 1956).


Brian Randell


School of Computing, Newcastle University, 1 Science Square, Newcastle upon Tyne, NE4 5TG
EMAIL = Brian.Randell at ncl.ac.uk   PHONE = +44 191 208 7923
URL =  https://www.ncl.ac.uk/computing/staff/profile/brianrandell.html

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