Pennsylvania_Railroad_class_D7
Class D7 (formerly Class A (anthracite), pre-1895) on the Pennsylvania Railroad was a class of 4-4-0 steam locomotive.[4] Fifty-eight were built by the PRR's Altoona Works (now owned by Norfolk Southern) between 1882–1891 with 68 in (1.73 m) drivers, while sixty-one of class D7a were constructed with 62 in (1.57 m) drivers.[1]
The D7 was fundamentally an anthracite-burning version of the PRR D6, with a larger fire-grate in order to burn the slower-burning, harder coal.[5]