Norfolk & Western M Class (1906)

The Norfolk and Western Railway's M, M1 and M2 classes (also known as the "Mastodon-class") were a series of 4-8-0 steam locomotives owned and operated by the Norfolk and Western Railway.
 These were the last significant deliveries of 4-8-0s in the United 
States. The N&W needed to get coal shipments over a mountain range, 
and powerful locomotives were needed. 4-8-0s were chosen over 2-8-2s
 because the 4-8-0 had better adhesive weight. Thus, in 1906, the first 
of the most numerous American class of 4-8-0 was contracted and built by
 Baldwin. The M1 class only differed from the M in valve gear. Because 
the M1's valve gear was poorly designed, there was excessive wear, 
making it impossible to keep them in alignment and valves properly set. 
The M1's were the first to be retired which led to the M2 class engines 
with a better designed valve gear with less excessive wear.
== Experiments ==
When bigger locomotives came to the N&W, some of the M's were used 
as switchers. But there was a problem: in some cities, smoke amount laws
 were broken, so the N&W decided to do an experiment with #1100 and 
#1112, both M2 types. First: they were both added with shorted flues and
 added with combustion chambers. They were also both added with a draft 
fan, driven by a steam turbine.
 Stokers and water level controls were added so the locomotives could be
 left alone for a long time. This gave both locos the name "Automatic 
Switcher". Mechanical lubrication was added so it was easier to maintain
 the parts that are hard to lubricate. Both of the engines tenders were 
modified to haul 20 tons of coal and 11,000 gallons of water. There were
 mechanical issues with this experiment however, so it didn't last very 
long. The draft fan would be occasionally damaged, because of the 
cinders. Ashes would also shoot out of the stack, so the crew was 
vulnerable to get covered. #1112 was added also with more heating 
surface, increasing the boiler pressure to 225 pounds. A cinder 
collector was added in front of the exhaust fan to collect cinders and 
bring them back to the firebox. But this experiment was still a big 
bust. Sadly, both #1100 and #1112 were retired in 1951, nearly ten years
 before the N&W gave up steam power in 1960.
== Survivors ==
Several locomotives survive. The most well known is No. 475, part of the 1906 order, which is currently operating on the Strasburg Rail Road in Pennsylvania. No. 433, of the 1907 order, is an outdoors static exhibit in a park Abingdon, Virginia, with a basic roof to protect it from rain. There are also two M2 locomotives, numbers 1118, 1134, and one M2c, 1151, which have resided in the Virginia Scrap Iron & Metal yard since 1950 until 2009. M2c #1151 was moved on 21 August 2009, M2 #1134 moved on 24 August, and M2 #1118 on 26 August. The 1134 has received cosmetic restoration and is now located at the Railroad Museum of Virginia, in Portsmouth Virginia. 1118 was traded for 0-6-0T no. 34 and will remain at NRHS chapter's 9th Street facility. 1151 was moved to the Virginia Museum of Transportation in Roanoke. 
==See also==
*Norfolk & Western M Class (1906)/Stock list locomotives
Category:Steam locomotives
Category:American locomotives
Category:Norfolk and Western locomotives
Category:Tender locomotives
Category:Eight-coupled locomotives
Category:4-8-0 steam locomotives
Category:4-8-0 locomotives
Category:Baldwin locomotives
Category:Locomotives
Category:Standard gauge locomotives
Category:American steam locomotives
Category:Standard gauge locomotives of the United States
Category:Richmond Locomotives
Category:Richmond Locomotive Works