Northern Pacific steam locomotive 4003 in helper service at Lester, Washington, circa 1915. Number 4003 is a class Z-2 built by Baldwin in 1910. Photo by Art Westborg, J.M. Fredrickson collection. Other Subject Classes: steam locomotive, roster photo

Northern Pacific steam locomotive 4004 at Easton, Washington, circa 1928. Number 4004 is a class Z-2 built by Baldwin in 1910 J.M. Fredrickson collection. Other Subject Classes: steam locomotive, roster photo

Northern Pacific steam locomotive 4004 at Helena, Montana, circa 1920. Number 4004, a class Z-2 built by Baldwin in 1910, is posed with its crew. Photo by Keller, J.M. Fredrickson collection. Other Subject Classes: steam locomotive, roster photo

Northern Pacific steam locomotive 4004 at Helena, Montana, circa 1920. Number 4004, a class Z-2 built by Baldwin in 1910, is posed with its crew. Photo by Keller, J.M. Fredrickson collection. Other Subject Classes: steam locomotive, roster photo

Northern Pacific steam locomotive 4004 at Stampede, Washington, circa 1928. Number 4004 is a class Z-2 built by Baldwin in 1910. Photo by Alma Floberg, J.M. Fredrickson collection. Other Subject Classes: steam locomotive, roster photo

Northern Pacific steam locomotive 4005 at Auburn, Washington, in 1942. Number 4005 is a class Z-3 built by Alco-Schenectady in 1913. Photo by J.M. Fredrickson. Other Subject Classes: steam locomotive, roster photo

Northern Pacific steam locomotive 4005 at Easton, Washington, on April 08, 1943. Number 4005 is a class Z-3 built by Alco-Schenectady in 1913. Photo by J.M. Fredrickson. Other Subject Classes: steam locomotive, roster photo

Northern Pacific steam locomotive 4005 at Easton, Washington, on April 08, 1943. Number 4005 is a class Z-3 built by Alco-Schenectady in 1913. Photo by J.M. Fredrickson. Other Subject Classes: steam locomotive, roster photo

Northern Pacific steam locomotive 4005 at Tacoma, Washington, on June 22, 1934. Number 4005, a class Z-3 built by Alco-Schenectady in 1913, is parked at the Tacoma engine facility after release from the shops. Photo by Herman Hunt, J.M. Fredrickson collection. Other Subject Classes: steam locomotive, roster photo

Northern Pacific steam locomotive 4005 at Tacoma, Washington, on June 22, 1934. Number 4005, a class Z-3 built by Alco-Schenectady in 1913, is parked at the Tacoma engine facility after release from the shops. Photo by Herman Hunt, J.M. Fredrickson collection. Other Subject Classes: steam locomotive, roundhouse