Data from DeGolyer, Vol 48, p. 277. Works number was 40671 in September 2013.
This was the second railroad to be chartered as the Kansas City & Memphis, incorporating on 17 December 1910. Its main lines linked Rogers and Fayetteville, Ark (30 miles), Cave Springs and Siloam Springs (20 miles), and Freeman to Monte Ne (6 miles). The company absorbed both the Arkansas, Oklahoma & Western and the Monte Ne Railways.
By July 1914, not after the railroad took delivery of this superheated freight Ten-wheeler, the KC&M went into receivership. The property was bid in a foreclosure sale a little more than four years later in October 1918.
At that time, the 7 was sold to the Midland Valley, which operated the engine for about nine years before being sold in December 1927 to the Missouri & Arkansas, which renumbered it 21. The M&A, which was based in Harrison, Ark, proved to be the 21's longest-running employer, running it for better than two decades before scrapping it in 1949.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | 7 |
| Locobase ID | 14153 |
| Railroad | Kansas City & Memphis |
| Country | USA |
| Whyte | 4-6-0 |
| Number in Class | 2 |
| Road Numbers | 7 |
| Gauge | Std |
| Number Built | 2 |
| Builder | Baldwin |
| Year | 1913 |
| Valve Gear | Walschaert |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 14 / 4.27 |
| Engine Wheelbase (ft / m) | 24.83 / 7.57 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.56 |
| Overall Wheelbase (engine & tender) (ft / m) | 53.58 / 16.33 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 116,000 / 52,617 |
| Engine Weight (lbs / kg) | 154,000 / 69,853 |
| Tender Loaded Weight (lbs / kg) | 140,000 / 63,503 |
| Total Engine and Tender Weight (lbs / kg) | 294,000 / 133,356 |
| Tender Water Capacity (gals / ML) | 7000 / 26.52 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 12 / 11 |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 64 / 32 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 64 / 1626 |
| Boiler Pressure (psi / kPa) | 200 / 1380 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 21" x 26" / 533x660 |
| Tractive Effort (lbs / kg) | 30,457 / 13815.08 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.81 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 157 - 2" / 51 |
| Flues (number - dia) (in / mm) | 21 - 5.375" / 137 |
| Flue/Tube length (ft / m) | 14 / 4.27 |
| Firebox Area (sq ft / m2) | 161 / 14.96 |
| Grate Area (sq ft / m2) | 27 / 2.51 |
| Evaporative Heating Surface (sq ft / m2) | 1686 / 156.63 |
| Superheating Surface (sq ft / m2) | 337 / 31.31 |
| Combined Heating Surface (sq ft / m2) | 2023 / 187.94 |
| Evaporative Heating Surface/Cylinder Volume | 161.80 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 5400 |
| Same as above plus superheater percentage | 6318 |
| Same as above but substitute firebox area for grate area | 37,674 |
| Power L1 | 11,310 |
| Power MT | 644.85 |