1871 Engine patented by Alexis de Bisschop of Paris
The engine proved modestly successful in spite of its relatively high gas consumption. It is described as a non-compression engine since there is no compression of the air/gas mixture before its admission to the cylinder. The thermodynamic cycle is very similar to that of the Otto-Langen engine where the air/gas mixture is admitted early in the expansion stroke followed by ignition of the mixture, with exhaust occurring during the return of the piston. It was the adoption of a slider-crank mechanism that significantly reduced noise and vibration. The small power output of the engine required its rating to be in manpower rather than horsepower units, where one manpower is approximately 125 watts.[1]
1878 J. E. H. Andrew and Co was granted a licence to build the engine in the UK. It was more popular in England than in France, probably because gas was cheaper. Some 2,000 engines were built in England before production ceased in 1894.