Northern Pacific 41.5-foot, open hopper car number 85421 in a yard at Denver, Colorado, on June 23, 1972. The car is part of the 85100-85499 number series. Photo by GJ Werkema. Other subject classes: frieght car, open hopper car, Selective Ballast car

The unloading gate detail of Northern Pacific Hart ballast car 87384 at Denver, Colorado, on September 20, 1973. The car is part of the 87000-87499 number series. Photo by GJ Werkema. Other subject classes: frieght car, open hopper car, Rodgers Ballast car

Northern Pacific 41.5-foot, open hopper car number 87937 on a turntable fan track at Denver, Colorado, on March 23, 1981. The car is part of the 87750-87999 number series. Photo by GJ Werkema. Other subject classes: freight car, open hopper car

Northern Pacific housing flat car 201304 in a train at Denver, Colorado, on January 26, 1982. The 50-foot flat car has a housing attached permenantly attached for use by maintenance-of-way crews. Other subject classes: flat car, maintenance-of-way

Northern Pacific maintenance-of-way flat car 203311 with boon and shovel load at Pasco, Washington, on February 14, 1981. Other subject classes: frieght car, flat car, maintenance-of-way

Northern Pacific flat car 206356 assigned to maintenance-of-way (MOW), is serving as a pile driver boom tender at Great Falls, Montana, on September 12, 1990. Pile Driver Tender Other subject classes: maintenance-of-way, flat car,

The B-end of Northern Pacific Hart ballast car 87384 showing its gate and brake equipment at Denver, Colorado, on September 20, 1973. The car is part of the 87000-87499 number series. Photo by GJ Werkema. Other subject classes: frieght car, open hopper car, Selectable Dump Ballast car

Northern Pacific 41.5-foot, open hopper car number 87467 in a train at Skykomish, Washington, on April 10, 1988. The car is part of the 87000-87499 number series. Photo by GJ Werkema. Other subject classes: frieght car, open hopper car, Rodgers Ballast car

Northern Pacific 41.5-foot, open hopper car number 87536 on a siding at Bellingham, Washington, on August 3, 1982. The car is part of the 87500-87749 number series. Photo by GJ Werkema. Other subject classes: frieght car, open hopper car, Selectable Dump Ballast car

Northern Pacific 41.5-foot, open hopper car number 87541 in a train at Skykomish, Washington, on April 10, 1988. The car is part of the 87500-87749 number series. Photo by GJ Werkema. Other subject classes: frieght car, open hopper car, 77T Ballast car