Cass Shay #11 and Western Maryland Big 6 pause at Oats Creek Tank to take on water before double-heading to Bald Knob. Back in the day, logging engines such as these often operated on temporary track in very remote wilderness areas. Railroad infrastructure, such as the classic wooden water tanks just didn't exist in that environment. Crews had to use whatever water supplies were available, and that often meant mountain springs, streams and ponds. The locomotives were equipped with steam siphons that utilized boiler pressure to create the vacuum necessary to pump ground water into their tender tanks. In this scene, a local spring has been piped into an old boiler shell and a retired tender tank. Shay 11 has her steam siphon hooked up to the former and is rapidly filling her tank. When 11 is full, the two engines will pull forward a few feet and Big 6 will have her turn at the tank. The Cass Scenic Railroad not only offers patrons scenic train ride, it offers them an authentic look at railroad operations from 60-100 years ago.