Gasmotorenfabrik Deutz, 1 hp
Style D1, Serial Number 17143

Gasmotorenfabrik Deutz engine design remained virtually unchanged throughout its production.  Otto designed this elegant inverted engine to take up less floor space.  These engines were built in sizes from 1 to 4 hp, incorporating an inertia governor. This example is a style D1 that replaced the previous style C around 1884.   Originally it was sold in Switzerland and was imported to the U.S. from there in 2015. This engine is the latest Gasmotorenfabrik Deutz slide valve engine on the flame ignition registry.  This beautiful example is privately owned.

“Crown Gas Pump” Built by National Meter, Serial Number 581

These compact engines were built between 1881 and 1886 and used for pumping water from street level to the higher floors of building in metropolitan areas.  A vertically-mounted water pump was driven by a bell crank, conveniently discharging through the cylinder water jacket before exiting into the building’s water system.  Designed in New York City by Lewis Nash (a holder of a great many early internal combustion engine patents), this engine utilized the non-compression cycle, burned illuminating gas for fuel, and incorporated carrier ignition.  All of the functions of the engine were carried out by a pair of eccentric-driven spool valves that paralleled the bore of the cylinder.  They were only built in the 4/10 hp size.  Of the estimated 1500 or so that were originally built, 14 survivors have been identified today.  This engine is completely original and is on long-term loan to the Coolspring Power Museum. Owned by Wayne Grenning.

Full-Size Reproduction 1/15 hp 1883 Forest

Built in Paris for a few years beginning 1881, Fernand Forest built small horsepower air cooled engines working on the non-compression cycle.  Incorporating a slide valve with flame ignition, these engines were fueled by city-supplied illuminating gas.  As with other non-compression engines of the early 1800s, Forest’s design operated on the only option available to sidestep Otto’s four-stroke cycle patent.  These engines were built by two companies in Paris, France, in sizes ranging from 1/15 to 1 hp, the latter being a 2500 pound beast. Many unusual features of this engine are quickly seen ranging from the “evans beam” actuated connecting rod to the spiral fin air cooled cylinder to the aft-mounted crankshaft.  A technical challenge Forest had to endure was to successfully make the slide valve.   All four surfaces of his valve have distinct functions each needing to be gas tight, rather than the two opposing flat faces on a typical four-stroke cycle valve.  Built by Wayne Grenning, the engine shown here is an exact full-size copy of the 1/15 hp engine on display at the Musée des Arts et Métiers in Paris. It is presumed total production of this curious engine never exceeded 1000 engines.  Two original full-size and two salesman samples survive today. 

Bisschop 1½ Manpower Reproduction

Built in the 1990s, this full-size reproduction is true to the German Sombart engines designed by Alexis de Bisschop.  This engine operates on a non-compression cycle that was typically built between 1878-1886.  As with other engines of this principal, it was built to sidestep the Otto four-stroke cycle patent.  Operation of this engine was a bit different than the other horizontal examples available at that time.  Both intake air and fuel were admitted through an eccentric-operated spool valve running parallel to the cylinder.  Ignition was by a flame jet located one-third the way up the cylinder.  Bisschop engines were licensed in America, England, Germany and France and built in sizes ranging from 1½ to 6 manpower.  Although very inefficient, they were a simple engine ideally suited for small power applications.  Once Otto’s four-stroke cycle patent became nullified in the late 1880s, all manufacturers of non-compression engines fell into obscurity.