Mountain Quarries Company 2-8-2 "Mikado" Locomotives in the USA

Class Details by Steve Llanso of Sweat House Media

Class 101 (Locobase 14078)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 45, p. 229. Works number was 36824 in August 1911.

Pacific Portland Cement ordered this Mikado and sized it to roll on 75 lb/yard (37.5 kg/metre) rail for the 7 miles between the quarries and the Southern Pacific junction at Auburn, Calif. It trailed a cylindrical Vanderbilt tender.

According to, a triple-span concrete bridge was built in 1912 during construction to handle the 4 trains a day. Quarrying the huge limestone formation took place from 1912 to 1939. In 1942 the tracks were pulled out for scrap metal for WWII, but the "No-Hands Bridge" remains standing. Its nickname reportedly refers to a horseback rider who rode "no hands" as he and his mount (who deserves at least half of the credit) picked their way across the bridge 150 feet above the gorge using only the narrow railbed.

The 101 had long since gone to the Ray & Gila Valley in 1916 and remained on the line until it was sold to Kennecott Copper in December 1943.

Principal Dimensions by Steve Llanso of Sweat House Media
Locobase ID14,078
RailroadMountain Quarries Company
Number in Class1
Road Numbers101
Number Built1
Valve GearWalschaert
Locomotive Length and Weight
Driver Wheelbase (ft / m)14 / 4.27
Engine Wheelbase (ft / m)31.08 / 9.47
Ratio of driving wheelbase to overall engine wheebase 0.45
Overall Wheelbase (engine & tender) (ft / m)60.79 / 18.53
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)185,000 / 83,915
Engine Weight (lbs / kg)232,000 / 105,234
Tender Loaded Weight (lbs / kg)133,500 / 60,555
Total Engine and Tender Weight (lbs / kg)365,500 / 165,789
Tender Water Capacity (gals / ML)7000 / 26.52
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)2940 / 11.10
Minimum weight of rail (calculated) (lb/yd / kg/m)77 / 38.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)51 / 1295
Boiler Pressure (psi / kPa)200 / 13.80
High Pressure Cylinders (dia x stroke) (in / mm)22" x 28" / 559x711
Tractive Effort (lbs / kg)45,173 / 20490.15
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.10
Heating Ability
Firebox Area (sq ft / m2)193 / 17.93
Grate Area (sq ft / m2)57 / 5.30
Evaporative Heating Surface (sq ft / m2)3903 / 362.60
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)3903 / 362.60
Evaporative Heating Surface/Cylinder Volume316.82
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation11,400
Same as above plus superheater percentage11,400
Same as above but substitute firebox area for grate area38,600
Power L16718
Power MT320.23