From the mid 19th century, gas engines were developed as feasible alternatives to steam engines, particularly for small power requirements as in workshops, warehouses, printing works and the food industry. Their development was spurred by the establishment of gasworks and pipelines to deliver coal gas throughout many cities.
The Otto-Langen free piston atmospheric gas engine was patented in 1866 and awarded the Grand Prize at the Paris Exposition of 1867 for being the most efficient gas engine ever produced. It became the world's first commercially successful internal combustion engine. About 2650 engines were manufactured in Germany until 1878, when Otto exhibited his silent gas engine at another Paris Exposition.
The engine shown at the Paris Exposition in 1867 had a 'Grecian Ionic' column (which was manufactured until 1872) and vertical crosshead guide rods. These guide rod engines were manufactured for only a few years. In the early years, two slide valves were utilised. Earlier engines of this type had not proven successful due to excessive friction and wear on the components; the roller-wedge clutch utilised by Otto is thus regarded as an essential feature of the success of the engine.
The engine is most likely to be one of the first ten manufactured by N A Otto & Co and is probably older than most of the remaining ones. Only four of the original Grecian column version are known to have survived, with one being owned by the Smithsonian Institution in Washington DC and another by the Rough and Tumble Engineers Historical Association of Kinzers PA.
A major disadvantage of the free piston engine was the noise and vibration when it was running. When the piston shot up after the gas explosion, the recoil force was transmitted directly to the engine foundations. This was so much of a concern that the engine could only be used in ground level installations.
Bryan Donkin Jr, 'Gas, Oil, and Air Engines', Charles Griffin & Co, London, 1894
Sigvard Strandh, 'Machines, an Illustrated History', Rigby, Adelaide, 1979
Wayne Grenning, 'In the Beginning: History of the Otto-Langen Engine', http://members.aol.com/wgrenning3/ottolangenhistory.html
University of Nottingham, 'The Otto-Langen free piston atmospheric engine in the Division of Mechanical Engineering, The University of Nottingham', www.nottingham.ac.uk/engines-group/ottolang.htm
Debbie Rudder, Curator, and Noel Svensson, Powerhouse Volunteer