Clean-running. Running completely clean stack most of the time, CPKC's Canadian Pacific Hudson #2816 "Empress" charges toward the Highway 41 grade crossing south of Horatio, Arkansas, near Milepost 442.5 on the railroad's Shreveport Sub, hauling her "Final Spike Steam Tour" special south toward it's next servicing stop at Ashdown, some 25 miles down the line.