Brunsviga D13 - Z18 - Calculator - 1940-1950 - Working model

A special double calculator is available! The Brunsviga 13 Z 18 (or D 13 Z 18) is a mechanical calculator, a so-called 'pinwheel calculator' (cylinder calculator), produced by the German company Brunsviga Maschinenwerke (formerly Grimme, Natalis & Co). It was colloquially also called the 'steel brain' (Gehirn von Stahl). The letter D stands for Double, and Z for Zehnerübertragung, meaning that this machine could perform a full decimal transfer in a very advanced way for its time, namely a complete carry-over in the revolution counting mechanism. A beautiful and historic item that is very rare and not often offered.

Overall, these machines were compact enough to move around, but heavy enough to stand stably on a desk during intensive use, which is typical of the durable, fully metal construction from that period.

Hopefully, this special machine will find a new owner who recognizes its historical and cultural value.