// Workers AI · dad joke modeWhat did the Great Northern class M-1 say? "I'm loco-motivated".

Great Northern Railway class M-1
GN 1951 at Skykomish, circa 1924
Type and origin Power type Steam Builder Baldwin Locomotive Works Serial number 34024-34028, 34074-76, 34104-5, 34824-34833, 34965, 34967-68, 34997-99, 35046-35052, 35088-89 Model Baldwin 16-40/64 DE Build date December 1909 – August 1910 Total produced 35 Rebuilder GN shops Rebuild date 1926-1927 (Rebuilt to M-2) 1930 (to O-7 Mikados) 1932 (to O-8 Mikados) Number rebuilt 35 (21 rebuilt to O-7, 3 to O-8)
Specifications Configuration: ​  • Whyte 2-6-8-0  • UIC (1′C)D n4v Gauge 4 ft 8+1⁄2 in (1,435 mm) Driver dia. 55 in (1.397 m) Adhesive weight 350,000 lb (160,000 kg) Loco weight 368,700 lb (167,200 kg) Boiler pressure 210 lbf/in2 (1.45 MPa) Cylinders Four, Mallet compound High-pressure cylinder 23 in × 32 in (584 mm × 813 mm) Low-pressure cylinder 35 in × 32 in (889 mm × 813 mm)
Performance figures Maximum speed 35–63 mph (56–101 km/h) Tractive effort 78,360 lbf (348.56 kN)
Career Operators Great Northern Railway Class M-1 Numbers 1950–1984 Retired 1929–1954 Disposition All scrapped after rebuilding to class M-2, O-7 & O-8

The Great Northern Railway M-1 was a class of American 2-6-8-0 locomotives introduced in 1910. A total of 35 of these Mallet locomotives were built by Baldwin Locomotive Works for Great Northern Railway (GN) in two batches; the first 10 in December 1909 and a further 25 in June to August 1910. These engines were unusual because of their uneven driving wheel sets, the front having six driving wheels while the rear had eight.

All M-1's were converted from compound to simple-expansion cylinders from 1926 to 1927 and reclassified M-2. 22 M-2's were dismantled between 1929 and 1931, with parts being recycled for the new class O-7 Mikados numbered 3376-3396 in 1930. Three O7 Mikados were rebuilt to O8 Mikados numbered 3397-3399 in 1932. The 13 unrebuilt M-2's lasted until dieselisation and were sold for scrap between 1949 and 1954. No examples were preserved in any form.

Images

• as M-1.
• as rebuilt to M-2.

References

• Keyes, Norman C. Jr.; Middleton, Kenneth R. (Autumn 1980). "The Great Northern Railway Company: All-Time Locomotive Roster 1861-1970". Railroad History (143). Boston, Massachusetts: The Railway and Locomotive Historical Society, Inc. ISSN 0090-7847.