Isotypes by Arntz (source: gerdarntz.org)

Gerd Arntz (1900 – 1988) was educated at a private academy in Düsseldorf and later attended the school of applied arts in Barmen (1921). He acquired the Düsseldorf studio of Otto Dix in 1925, when Dix moved to Berlin.
Arntz traveled widely through Europe, and was a core member of the Cologne Progressive Artists Group. From 1926 Otto Neurath sought his collaboration in designing pictograms for the Vienna Method of Pictorial Statistics (Wiener Methode der Bildstatistik; later renamed Isotype).
From the beginning of 1929 Arntz worked at the Gesellschafts- und Wirtschaftsmuseum (Social and economic museum) directed by Neurath in Vienna. Eventually, Arntz designed around 4000 pictograms. Between 1931 and 1934 he traveled periodically to the Soviet Union (along with Neurath and Marie Reidemeister) in order to help set up the ‘All-union institute of pictorial statistics of Soviet construction and economy’, commonly abbreviated to IZOSTAT (ИЗОСТАТ). After the brief civil war in Austria in 1934 he emigrated to the Netherlands, joining Neurath and Reidemeister in The Hague, where they continued their collaboration at the International Foundation for Visual Education.

Source: Wikipedia