As additional information, both the NYC and PRR, with limited use by the B&O, had extensive track pans and water level/treatment facilities, for various steam locomotives to "scoop" tender makeup water, without stopping. The NYC continued to "perfect" the process of "scooping" water while underway, and eventually developed those large PT "Centipede" tenders for most all of their Hudsons and Niagara class passenger locomotives. The PT tenders, with those large air vent discharge pipes were designed to "scoop" water at speeds of 80 MPH, thus the requirement for all those large air vent discharge pipes, on both sides of the tender.
The general idea of "scooping" water into the tender was NOT to completely fill the tender, but keep a more than half-full tender, most of the trip. Thus, water was "scooped" often at regular intervals between New York and Chicago, on the NYC four track main line. The Fireman would operated an air valve handle on his front side of the tender, and when the Engineer signaled him that they were over the track pan, the Fireman would then lower the water scoop. Upon another signal from the Engineer, the Fireman would raise the scoop.
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As additional information, the PT tenders had drastically enlarged coal carrying capacity of 46 tons, since the water carrying portion could be correspondingly reduced, due to the ability to "scoop" water many times enroute. With such a large coal load, those Hudsons and Niagaras equipped with PT tenders, would only need to stop and take on coal once (at Cleveland, OH) between Harmon New York and Chicago.
