A Slide Adder

D Moews sent me a zip file containing code that constructs slide adders like those due to Kummer and Troncet. . The 3 stl files assemble into an adding machine. Part of the README that comes with the zip file is shown below; the complete README file with all references is included. D. Moews has placed the zip file in the public domain. It is available for download at: http://djm.cc/slide-adder-0.03.zip