Mechanical Calculating Aids

Abstract

Since overviews regarding other manufacturing countries such as the USA and Germany are already available, the chapter “Mechanical Calculating Aids” is essentially limited to Switzerland. This chapter describes calculating tables, slide bar adders, and mechanical calculating machines, for example, the Millionaire, Madas, Precisa, and Stima brands. A tabular overview lists the attributes of all known products from Switzerland. The legendary Millionaire, a partial-product multiplying machine, was the first commercially successful direct multiplying machine. On the basis of serial numbers and previously unknown documentation from the H.W. Egli AG, Zurich, an attempt is made to date this four-function calculating machine. A global survey reveals information about the known Millionaire machines, and the catalog of the Schweizer Mustermesse Basel, which was issued every year from 1917 (founding) to 2019 (final year), was evaluated. Little information is available in regard to piece numbers, prices, and patents.