Is that a Hart gondola? It appears to have a hopper-style drop
Not THAT early, delivered in 1913. And not a Hart car; it's a Bettendorf design, SP Class W-50-4 (not sure if UP used the same class number, though their CS system was the same). It's a ballast car, and never did have much lettering.
Tony Thompson Editor, Signature Press, Berkeley, CA