Philadelphia & Reading 2-4-2 "Columbian" Locomotives in the USA

Class M1-a/M1-b (Locobase 8879)

Data from TraitT pratique de la machine locomotive ... By Maurice Demoulin, 1898

Librairie polytechnique, Baudry et Cie, p 380 and Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volumes 17, p. 170 and 18, p. 137.See also "A Fast Compound Locomotive", Railroad and Engineering Journal, Volume 66, No 6 (June 1892), p. 257; and 1907 Catalogue of Mechanical Engineering Collection in the Science Division of the Victoria & Albert Museum (Board of Education South Kensington)., pp 92. (Thanks to Chris Hohl for his 6 October 2017 email reporting several errors in the original entry.) Baldwin works numbers were 12433 in January 1892; 12672, 12676, 12679-12680 in May; 13370 in April 1893; 13408-09, 13411-13413 in May.

Baldwin's estimates for both batches came in at a low 76,000 lb (34,473 kg) on the drivers, 120,000 lb (54,431 kg) for the engine. The Catalogue of exhibits for the 1893 Exhibition, it reported the higher weights shown in the Locobase specs above as "actual".

Also in the catalogue, Baldwin made "special mention" of the suppliers of materials and appliances to this design:

Boiler and fire-box steel Wellman Iron and Steel Co., Thurlow, Pa.

Tubes Reading Iron Co., Reading, Pa.

Tires Standard Steel Works, Philadelphia, Pa.

Wrought-iron wheels (Vauclain pattern) Standard Steel Works, Philadelphia, Pa.

Metallic packing United States Metallic Packing Co., Philadelphia, Pa.

Sight feed-lubricator Detroit Lubricator Co., Detroit, Mich.

Injectors William Sellers & Co., Incorporated, Philadelphia, Pa.

Driving brake American Brake Co., St. Louis, Mo.

Tender and train brake . . Westinghouse Air Brake Co., Pittsburgh, Pa.

Tender-coupler The Hazleton New Universal Interlocking Coupler Co.,

As unusual as the adoption of the Bicycle wheel arrangement was in the US, production of ten Bicycles with the four-cylinder Vauclain compound layout--one 10 1/2" (267 mm) piston valve supplying steam to the HP/LP cylinder assembly on each side--in a camelback profile was rarer still. As was common in early Wootten boilers, the relatively long combustion chamber added heating surface area to the firebox total. In these engines, Baldwin specifications reveal, that supplemental area came to 45.375 sq ft (4.22 sq m). Overall, the design had one of the lowest evaporative heating surface area-to-grate area ratios of any US locomotive.

As usual, the REJ entry pronounced the work done by the class soon after its introduction as "very good." It had averaged 52.1 mph (85 kph) over the Bound Brook Line of 85.1 miles (137 km) between Jersey City and Philadelphia. One run whose start had been delayed posted speeds as high as 79.6 mph (128 kph) trailing "four heavy cars" and "there was an adverse wind blowing."

They didn't persist in this arrangement for long.

One (682) was rebuilt as an Atlantic in May 1899, the others as N-4a camelback Moguls in 1904; see Locobase 12664.