(Type used in large, well-ventilated mines since 1870’s. Burned coke or hard coal to reduce smoke. Built low to ground for good clearance. Cylinders placed inside frame, under the boiler, to reduce engine width.)

(Among the fastest express locomotives operating in U.S. during the 1880’s. Considered a remarkably advanced design at the time of its construction.) 

 
Vauclain compound, high-wheel Columbia type, between 1892 & ‘93.

(Eleven similar machines were built for the Philadelphia and Reading. The wheel arrangement wasn’t successful, and all engines of this class were remodeled along conventional lines within a few years.)