Pony engine

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a small locomotive for switching cars from one track to another.

See also: Pony

References in periodicals archive ?
The short story by William Dean Howells entitled "The Pony Engine and the Pacific Express," published in 1892, is perhaps the earliest instance of a pedomorphized train engine.
Like Howell's engine earlier and Thomas later, the Little Engine That Could is a pony engine, and her story is that of a young train engine making an early exploration of the world beyond the space of her childhood home.
Thomas begins as a pony engine, and his first book is all about how he proves himself "really useful" and therefore able to handle his own Branch Line.
This proved challenging, as the carburetor on the gasoline pony engine was on its original assembly.
Oliver was driving the AR, which was attached to a gigantic New Holland baler equipped with its own pony engine and a voracious serrated plunger that rose and fell like a Tyrannosaurus Rex savaging a chicken.
We took great delight in the mechanical carnage, and the alacrity with which Oliver leapt from his seat to kill the pony engine.