San Luis Southern 2-6-0 "Mogul" Locomotives in the USA

Class Details by Steve Llanso of Sweat House Media

Class 102 (Locobase 14680)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Vol 62, p 95. See also the account of the SLS and the SLVS at "Mesita, Colorado and the Ghost Railroad" at and "Wagon Wheel Gap Route and the Denver & Rio Grande Railway" found at Richard Cutter's . Works number was 52253 in August 1919.

Colorado issued a charter to the backers of this road to build a line from Blanco, Colo south to Taos, NM. The owners were the Costilla Estates Development Corporation, which wanted to open up farmland in southern Colorado. They dug a reservoir in 1909, says the slvufo account, and "platted the towns of San Acacio, Mesita, and Jarosa. In Jarosa, about 10 miles South of Mesita, the Seventh-day Adventists set up a colony and cooperative farm." Jarosa was the SLS's actual southern terminus when the 30-mile long (50 km) railroad was completed on 3 November 1910.

The Wagon Wheel Gap account describes the line as "The railroad that came and went with no one noticing ...[ellipsis in the original], but states "this line ran south through the best crop areas in the San Luis Valley and was to connect to Taos, NM but never completed. It carried produce that fed the plates of every one from the rich Mine Owners of Denver and down to the poor miners in the high mountains. "

This Mogul was the only SLS engine ever acquired directly from a builder. The other six engines were two ex-Lake Shore & Michigan Southern Ten-wheelers originally produced by Brooks and renumbered 100-101 and four ex-Denver & Rio Grande Western C-28 Consolidations built by Baldwin in 1889 (Locobase 1453) and renumbered 103-106.

Finances always seemed short and relatively scarce rainfall failed to fill the reservoir. So the CEDC went bankrupt and the SLS was reorganized as the San Luis Valley Southern in 1928. But the railroad provided passenger service from 1910 to 1946 on the "loneliest railroad in Colorado". Steam service ended in 1957.

Diesels, including a home-built engine that resembled a caboose, served the valley's freight customers until 1996.

Principal Dimensions by Steve Llanso of Sweat House Media
Locobase ID14,680
RailroadSan Luis Southern
Number in Class1
Road Numbers102
Number Built1
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m)11 / 3.35
Engine Wheelbase (ft / m)19 / 5.79
Ratio of driving wheelbase to overall engine wheebase 0.58
Overall Wheelbase (engine & tender) (ft / m)
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)85,000 / 38,555
Engine Weight (lbs / kg)100,000 / 45,359
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)
Tender Water Capacity (gals / ML)
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)
Minimum weight of rail (calculated) (lb/yd / kg/m)47 / 23.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)54 / 1372
Boiler Pressure (psi / kPa)180 / 12.40
High Pressure Cylinders (dia x stroke) (in / mm)17" x 24" / 432x610
Tractive Effort (lbs / kg)19,652 / 8914.01
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.33
Heating Ability
Firebox Area (sq ft / m2)93 / 8.64
Grate Area (sq ft / m2)16.60 / 1.54
Evaporative Heating Surface (sq ft / m2)1043 / 96.90
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1043 / 96.90
Evaporative Heating Surface/Cylinder Volume165.42
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation2988
Same as above plus superheater percentage2988
Same as above but substitute firebox area for grate area16,740
Power L13875
Power MT301.51

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Wes Barris