Awesome Old Machine

Steam engines had nicknames for all the different wheel arrangements.

For example, this one you pictured (nice pix, BTW) is a "Northern."

Some examples...
[SIZE=+0]2-4-2 Columbia
[SIZE=+0]2-6-0 Mogul
[SIZE=+0]2-6-2 Prairie
[SIZE=+0]2-8-0 Consolidation
[SIZE=+0]2-8-2 Mikado
[SIZE=+0]2-8-4 Berkshire (pronounced Burke-sher; from the Boston and Albany, part of the New York Central system, which crossed the Berkshire mountains in Massachusetts)
[SIZE=+0]2-10-0 Decapod (obvious)
[SIZE=+0]2-10-2 Santa Fe
[SIZE=+0]2-10-4 Texas (from Texas and Pacific)
[SIZE=+0]2-10-4 Selkirk (from the Selkirk Mountains on the Canadian Pacific)
[SIZE=+0]4-4-0 American (this became the ubiquitous type for railroads pushing west in the mid 19th century)
[SIZE=+0]4-4-2 Atlantic (from the Atlantic Coast Line)
[SIZE=+0]4-4-4 Jubilee
[SIZE=+0]4-6-0 Ten-wheeler
[SIZE=+0]4-6-2 Pacific (from the Missouri Pacific)
[SIZE=+0]4-6-4 Hudson (the New York Central main line follows the Hudson River)
[SIZE=+0]4-8-0 Twelve-wheeler
[SIZE=+0]4-8-2 Mountain (from the Allegheny Mountains of the Chesapeake and Ohio)
[SIZE=+0]4-8-4 Northern (from the Northern Pacific)
[SIZE=+0]4-10-0 Mastodon
[SIZE=+0]4-10-2 Southern Pacific
[SIZE=+0]4-10-2 Overland (from the Union Pacific)
[SIZE=+0]4-12-2 Union Pacific
[SIZE=+0]A few articulated and other multi-cylinder locomotive types were given names other then Mallet, viz:
[SIZE=+0]2-6-6-6 Allegheny (from the Chesapeake and Ohio)
[SIZE=+0]2-8-8-4 Yellowstone (from the Northern Pacific - the name came from the River and the Division over which the locomotives ran)
[SIZE=+0]4-6-6-4 Challenger (from the Union Pacific)
[SIZE=+0]4-8-8-4 Big Boy (from the Union Pacific) [SIZE=+0]"Mallets" were normally 2-8-8-0 arrangement but could vary.[/SIZE]

Info for anyone interested in steam locomotives...
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