Progreso a Merica / Progreso a Merida 4-4-0 Locomotives in Mexico


Class Details by Steve Llanso of Sweat House Media

Class J Rafael de Regil (Locobase 12436)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 23, p.76. Works numbers were 18004 in August 1900.

This appears to be a replacement for one of the earlier P & M Eight-wheelers; Locobases 11682 and 11803 show earlier engines that were built to the same specs. In other words, the P &M bought the same small 4-4-0s over a 20-year period. Pays to know your market, I guess.

The P & M was later amalgamated with other railroads into the United Railroads of Yucutan.


Class Merida (Locobase 11682)

Data from Baldwin Locomotive Works Specification for Engines, 1888, as digitized by the DeGolyer Library of Southern Methodist University Vol 14, 215. Works numbers were 9615-9616 in November 1888.

P a M was a 24-mile railroad that began construction in July 1873, but wasn't completed until 12 September 1882. It later extended a branch to Soluta 30 miles away, which accounts for the name of the second locomotive. The country was described in one account as "flat and hot".

They later wound up on the United Railways of Yucutan with numbers 9-10.


Class Progreso (Locobase 11803)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 11, p.115. Works numbers were 6507 in December 1882.

The P & M later joined the other railways in the area in the Unidos de Yucatan. At that point, the Progreso was renamed Adelaida.

Principal Dimensions by Steve Llanso of Middle Run Media
ClassJ Rafael de RegilMeridaProgreso
Locobase ID12436 11682 11803
RailroadProgreso a MericaProgreso a MeridaProgreso a Merica
CountryMexicoMexicoMexico
Whyte4-4-04-4-04-4-0
Number in Class121
Road Numbers103
GaugeStdStdStd
Number Built121
BuilderBurnham, Williams & CoBurnham, Parry, Williams & CoBurnham, Parry, Williams & Co
Year190018881882
Valve GearStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m) 6.50 / 1.98 6.50 / 1.98 6.50 / 1.98
Engine Wheelbase (ft / m)19.08 / 5.8219.08 / 5.8219.08 / 5.82
Ratio of driving wheelbase to overall engine wheelbase 0.34 0.34 0.34
Overall Wheelbase (engine & tender) (ft / m)
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)
Engine Weight (lbs / kg)
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)
Tender Water Capacity (gals / ML)1600 / 6.061600 / 6.061600 / 6.06
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT)
Minimum weight of rail (calculated) (lb/yd / kg/m)
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)52 / 132152 / 132151 / 1295
Boiler Pressure (psi / kPa)150 / 1030130 / 900140 / 970
High Pressure Cylinders (dia x stroke) (in / mm)12" x 22" / 305x55912" x 22" / 305x55912" x 22" / 305x559
Tractive Effort (lbs / kg)7768 / 3523.516732 / 3053.597392 / 3352.96
Factor of Adhesion (Weight on Drivers/Tractive Effort)
Heating Ability
Tubes (number - dia) (in / mm)94 - 2" / 5194 - 2" / 5194 - 2" / 51
Flues (number - dia) (in / mm)
Flue/Tube length (ft / m) 9.37 / 2.86 9.37 / 2.86 9.37 / 2.86
Firebox Area (sq ft / m2)63.40 / 5.8963.40 / 5.8963.40 / 5.89
Grate Area (sq ft / m2)12.10 / 1.1211.70 / 1.0912.10 / 1.12
Evaporative Heating Surface (sq ft / m2)521 / 48.42521 / 48.42521 / 48.42
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)521 / 48.42521 / 48.42521 / 48.42
Evaporative Heating Surface/Cylinder Volume180.90180.90180.90
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation181515211694
Same as above plus superheater percentage181515211694
Same as above but substitute firebox area for grate area951082428876
Power L1378332783463
Power MT

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