The World’s Smallest Mechanical Parallel Calculator: Discovery of Original Drawings and Patent Documents from the 1950s in Switzerland

  • Herbert BrudererEmail author
Conference paper
Part of the IFIP Advances in Information and Communication Technology book series (IFIPAICT, volume 491)


The Austrian engineer Curt Herzstark invented the world-renowned mechanical pocket calculator Curta. The books and the papers on the history of computing mention two models, Curta 1 and Curta 2. In November 2015 original drawings and patent documents on a multiple Curta were discovered in Switzerland. This device is supposed to be the world’s smallest mechanical parallel calculator.


History of computing Pocket-sized mechanical parallel calculator Discovery of drawings Documents on a multiple Curta 



The author is very grateful to Stefan Beck from the typewriter museum in Pfäffikon near Zurich.

Copyright information

© IFIP International Federation for Information Processing 2016

Authors and Affiliations

  1. 1.ETH ZurichZurichSwitzerland

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