1941 Lima 2-6-6-6 (#7824) at the B&O Railroad Museum

By the 1940's, the Chesapeake & Ohio Railway (C&O) and Lima Locomotive Works developed a new type of steam locomotive that could tackle the tough Allegheny Mountain grades more efficiently than the current 2-6-6-2's and 2-8-8-2's. The new locomotive had a 109-inch wide boiler, which was 2 inches larger than the "Big Boy" locomotive and a fire box that was so large it required a six-wheel trailing truck to support it. The locomotive only had six axles, instead of the usual eight. This new 2-6-6-6 locomotive was known as the "Allegheny" after the mountains it was designed to conquer.

The "Allegheny" locomotives were quite successful pulling slow coal drags through the mountains, but they could also travel as fast as 60 miles per hour pulling occasional passenger trains. By the end of 1948, there were 60 of the 2-6-6-6 locomotives on the C&O's roster.

The No. 1604 is a simple articulated locomotive. An articulated locomotive is a locomotive that has two sets of cylinders each driving a separate set of wheels, which are mounted in two separate frames connected by a pivot joint. The boiler sits on the leading frame and is attached to the second frame. The lead frame can swivel radically at the pivot joint. This permits the locomotive to negotiate curves. All types of articulated locomotives are called "Mallets." On the simple expansion articulated locomotive, all cylinders receive steam at boiler pressure (high pressure steam).

Beginning in 1952, the "Allegheny" was being replaced with new efficient diesel locomotives. The No. 1604 was one of two "Alleghenies" that escaped from scrapping. In 1986, the No. 1604 was transferred to the Baltimore & Ohio Railroad Museum. The other "Allegheny," No. 1601, resides at the Henry Ford Museum in Dearborn, Michigan. The "Allegheny" locomotive series was considered one of the heaviest and most powerful American-built steam locomotives ever built.

This train was massive, which made it difficult to get any decent shots from the side. Especially when there was another locomotive behind you not more than 10 feet away. There was also a wooden walkway between the trains on the opposite side, but at least that allowed access to the cab!

Many of the valves were labeled.

I had no idea what some of them did.

The steam cocks were actually valves you had to open and close by hand!

********************************************************************************