Northern Pacific Railroad rotary snow plow number 10 clearing the westbound mainline at Martin, Washington in February, 1945. Photo by J.M. Fredrickson. Other Subject Classes: rotary snow plow, steam locomotive, maintenance of way

Northern Pacific Railroad rotary snow plow number 10 stopped after a run at Upham, Washington, on January 25, 1943. Photo by J.M. Fredrickson. Other Subject Classes: rotary snow plow, steam locomotive maintenance of way

Northern Pacific Railroad rotary snow plow number 42 clearing the westbound mainline at Martin, Washington in 1949-50. Photo by J.M. Fredrickson. Other Subject Classes: rotary snow plow, steam locomotive, maintenance of way

Northern Pacific Railroad rotary snow plow number 42 and crew at Martin, Washington in 1949-50. Photo by J.M. Fredrickson. Other Subject Classes: rotary snow plow, maintenance of way, railroad crew

Northern Pacific Railroad rotary snow plow number 42 clearing the westbound mainline at Martin, Washington in February, 1945. Photo by J.M. Fredrickson. Other Subject Classes: rotary snow plow, maintenance of way

Northern Pacific Railroad rotary snow plow, number 42 clearing the westbound mainline at Martin, Washington in February, 1945. Photo by J.M. Fredrickson. Other Subject Classes: rotary snow plow, maintenance of way

Northern Pacific Railroad rotary snow plow number 42 clearing the westbound mainline at Martin, Washington in February, 1945. Photo by J.M. Fredrickson. Other Subject Classes: rotary snow plow, maintenance of way

Northern Pacific Railroad rotary snow plow number 9 derailed in the Tunnel number 2 cut on Stampede Pass near Martin, Washington in 1949-50. Photo by J.M. Fredrickson. Other Subject Classes: rotary snow plow, maintenance of way

Northern Pacific Railroad rotary snow plow number 9 derailed in the Tunnel number 2 cut on Stampede Pass near Martin, Washington in 1949-50. Photo by J.M. Fredrickson. Other Subject Classes: rotary snow plow, maintenance of way

Northern Pacific Railroad rotary snow plow number 9 derailed in the Tunnel number 2 cut on Stampede Pass near Martin, Washington in 1949-50. Photo by J.M. Fredrickson. Other Subject Classes: rotary snow plow., maintenance of way