A Brief History of the MarqueManufactured in Berlin 1923-1924 Only one example of this marque survives. It has ash wood frame fitted with a longitudinal horizontally-opposed engine by Bosch Stockdorfer Motorenwerke AG, modeled after the Douglas. They also built a machine with a 137cc two-stroke engine. Hirsch was one of three companies who built ash-framed machines at that time, the others being Berkamo and HOCO. The example of the Douglas boxer engine was followed by many factories in Germany and elsewhere in Europe; in England we find the same engine concept in the Wooler of 1922, and also in the Italian Fongri.
The idea of rotating the engine 90 degrees was later developed by BMW, laying the foundations for a long career of the horizontally-opposed transverse twin "boxer" engine.Sources: Bretti Brothers, et al.