Driven by coal  

If you are asked about the most successful French cars, The Citroën 11CV quickly comes to mind. Of course, when this era began in 1934, no one could have guessed this success. The construction of the later 11CV was the implementation of specifications of the company boss personally. André Citroën envisioned a vehicle that primarily meet three important criteria – it had to be fast, economical, and safe.   The most powerful four-cylinder version had a 1,911cc in-line engine installed above the front axle, the type designation is 11CV. This stood for the formula of the control horsepower, in which the displacement was classified. The engine produced 56 hp and consumed about 12 liters of gasoline per 100 kilometers. Production continued int Second World War.   With the occupation of France by German soldiers, however, the rationing of gasoline for civilian use was ordered and the vehicle engines were converted to wood gas operation. The necessary adjustments were made by the company ‘Fab Elgazo Tarbes’, which fitted two powerful cylinders into the body below the front bumper, each of which pulled up to the bonnet on the side of the fenders. Coal was poured into these two metal containers and ignited. After about 30 minutes, enough methane gas was produced, which rose to the top and was fed into the carburetor. Of course, the engine did not develop the usual power, but even if only a third of the former horsepower was available, the car at least was running!

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From February 14 - 24, 1935, the Automobile and Motorcycle Exhibition was held in Berlin. The Berlin coachbuilding company Erdmann & Rossi (E&R) exhibited two very similar cars there: These were a 2.9-ltr Mercedes Benz with fashionable streamlined bodywork and a two-seater Opel 2-ltr streamlined sport roadster. According to E&R commission slip #22563, the client for the 2.9-Ltr. Mercedes Benz was Erdmann & Rossi themselves. This allows the interpretation that the car was manufactured at Erdmann & Rossi's own expense and risk. This is somewhat different with the Opel 2-Ltr. streamlined sports roadster. Thankfully, we have a copy of the E&R commission bill #2566 from Erdmann & Rossi. Adam Opel AG is named as the purchaser. So it can be assumed that Opel at least paid for the body. Whether Opel also provided and paid for the chassis # 11417, we do not know. Furthermore, it is noted on the commission bill that the car is for an exhibition. The agreed delivery date was Feb. 10, 1935. The roadster had a fully retractable top, rear wheels covered but removable, two electric winkers, and a Bo wiper. At the end of 1935, Erdmann & Rossi delivered a Mercedes Benz with streamlined bodywork in the same design to the King of Iraq, but for this the chassis of a Mercedes-Benz Type 540K was used. What became of the sleek Opel 2-Ltr. streamlined sports roadster, we do not know. Perhaps you do know! Ironically: At the 1935 Automobile and Motorcycle Show, Opel introduced an innovation of enormous significance on your own stand. The new Opel Olympia no longer had a chassis, but featured a self-supporting body. This new technology had the advantage that the cars could be produced faster, lighter and therefore cheaper. On the other hand, the chassis-less car no longer offered body builders the basis for producing individual bodies. The consequence of using this technology, which is still valid today, was a gradual decline of the b....