It was cheaper for the PRR to lease servicable steam, such as these Reading T-1s, rather than perform expensive class repairs (essentially rebuilds) on their own steamers destined to the scrap heap soon at any rate. Because of that philosophy railfans were able to catch foreign steam in Pennsy outposts like Renovo, PA., and Columbus OH., near the end of steam. Of the nine T1s leased, most were scrapped in '57 except for 2128, which lasted until 1960.
Either a freight train being helped over a steep grade or a long passenger or freight train requiring more engines. This album includes Helpers and double heading trains of the old days both steam and diesel.