We are in Rowlesburg, WV on Aug. 17, 1975 and an eastbound coal drag has reached the bottom of Cheat River Grade and is getting a roll on things for the climb up Cranberry. Back in the days of friction bearing trucks, this is what a coal drag looked like coming through town. What we called "brake shoe smoke" was actually the oil that had leaked by the seals in the bearing and been deposited on the inside of the wheel. When the brake shoe heated the wheel, the oil began to smoke. In this case, the brakes had already been knocked off and the pusher was shoving on the rear, but the oil continued to smoke until the wheels cooled off.