It was also reprinted as part of the Charles Babbage Institute reprint series and is available in paperback from Amazon: https://www.amazon.com/Operation-Automated-Controlled-Calculator-Institute/d... for anyone who wants a physical copy. BLS On Saturday, October 10, 2020, 2:13:02 PM EDT, Duane Craps via vcf-midatlantic <vcf-midatlantic@lists.vcfed.org> wrote: There is a manual on Bitsavers :http://bitsavers.trailing-edge.com/pdf/harvard/MarkI_operMan_1946.pdf On 10/9/2020 12:47 PM, W. Bryan Caudle via vcf-midatlantic wrote: -- Duane Craps sdɐɹɔ ǝuɐnp On 10/9/2020 12:47 PM, W. Bryan Caudle via vcf-midatlantic wrote: -- DuaneCraps sdɐɹɔ ǝuɐnp