CAPPilot posted:The PRR did not have "wagontop" boxcars. They did have round roof boxcars, which were of a different design. PRR's round roof cars were flat roof boxcars where the roof was replaced with a rounded one for more internal volume, but still have clearance for PRR's low tunnels.
I believe the B&O's wagontop cars were specifically built that way to limit water leakage at the roof line. I don't have either type of car, so it would be interesting if someone posted a picture of the two together to see the difference.
Thats correct about the design of B&O wagon top boxcars ROn. It's a neat car and I own one of Weaver's B&O wagon top boxcars. Picked it up at a train show for a great price.