by Emmett Smith
Here is a picture of the Q2’s immediate predecessor, the Pennsylvania Railroad’s Q1. You can see for yourself the opposed cylinders on this rigid-frame 4-6-4-4 arrangement. It was not a success because the rear cylinders, facing forward, collected abrasive grit on the piston shafts, thrown up by the drivers especially when the engineman was sanding for traction.
The picture below of the Q2 is a nice example that allows a close comparison of design differences. The more conventional distribution of the four cylinders is obvious, and the opposite wheel arrangement, 4-4-6-4.
The Q2 dragged far and away more freight. But the original purpose of the Q1 is revealed in her streamliner role, below.
[Emmett R Smith all text-rights reserved & all picture-rights revert to original holders 6 June 2009]