The Fontaine Fiasco:
Most of the locomotives in the Museum of Retrotech have had some degree of success, or at least been a brave try that yielded useful knowledge. The Fontaine concept, however, appears to be devoid of any redeeming features.
The monstrosity shown above was built in 1881 at the Grant Locomotive Works, of Paterson, New Jersey. It was designed by Eugene Fontaine, of Detroit. The engine was built with the driving wheels ABOVE the boiler, their tread pressing on and transmitting motion to the carrying wheels by frictional contact. The designer claimed this would increase the speed of the engine for the same boiler pressure, though why he should have thought so is a bit of a mystery; it would appear that all that has been introduced is another place for slipping to occur. The likeliest explanation is that he was trying to gear up the real driving wheels so they turned faster than the "air-wheels". Slightly larger driving wheels would surely have been an easier way to the same end.
This picture (an engraving apparently taken from the photograph above, as was normal before photos could be printed) lends support to this theory. Some helpful soul has dotted-in the hidden parts of the wheels, showing that they do indeed step up the speed of the rail wheels, by a modest ratio of 1.4 to 1, if my measurements from the diagram are accurate. It does not seem worth the bother.
This locomotive with two wheels up in the air really was built and put in service. The engine was tried on all kinds of trains, but proved inferior in every respect to the ordinary engines of the same capacity. After many modifications- none of which helped much- it was rebuilt as an ordinary eight wheel engine.