Data from Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 18, p.150,. Works number was 13186 in January 1893.
This tank had the dimensions of a typical light 4-4-0 of the time, but with the auxiliary trucks distributed to allow easier bi-directional running. When the B&M took over the C&M in 1895, it assigned new road numbers and at some later date, removed both auxiliary trucks. 57 was sold in March 1912 to Grovet Paper Company.
Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 28, p. 206,. See also the Steamtown National Historical Site's Special History Study on the Berlin Mills Railway 2-4-2T Locomotive No. 7, as archived at [], last accessed 18 October 2013. (Thanks to Chris Hohl for his 27 July 2021 email supplying the coal capacity and correcting the tube length.) Works number was 27370 in February 1906.
Berlin Mills was a New Hampshire-based timber company. Curves to be negotiated ran as tight as 48.9 deg, which the specification helpfully translates as a 119 ft radius.
This double-ender resembled several other four-axle engines of this type, some of which would later join the 6 at Berlin Mills. Its saddle tank was to "arranged to be removed without interfering with throttle."
Data from [], last accessed 21 July 2011. Vulcan works numbers were 1679 in January 1911, 2637 in May 1917, and 3047 in May 1920.
Unusual saddle-tanker with small drivers. Its specifications bear out an impression that the 7's design held its own among similar four- and six-coupled industrial saddle tanks for size and power.
In addition to its unusual double-ender wheel arrangement, the locomotive's appearance includes a fully enclosed cab, high-pitched boiler supporting a large saddle tank and topped by a slightly flared stack, two smooth sand domes that flank a steam dome dotted with prominent rivets.
The Berlin Mill's electrolytic plant that produced chlorine used in bleaching papers also produced caustic soda as a byproduct, noted the NPS's detailed survey. "In 1908", the account adds, "the company ceased dumping waste caustic soda into the river and instead began marketing it as White Mountain Brand Caustic Soda."
Continually increasing its product lines after World War I meant expanding plant trackage (eventually totalling 13.5 miles (21.7 km) and traffic grew over the 3 3/4 mile (6 km) spur to the Grand Trunk Railway's main line. Rail weighed 65-70 lb/yard (32.5 to 35 kg/metre).
Before the end of the decade, the Brown Company bought larger Prairie-type saddle tanks to handle increased traffic; see Locobase 15493.
As demand declined, the Brown Company began disposing of its motive power. In November 1944, Groveton Paper Company of Groveton, NH, bought the 7 to replace an antique locomotive. It operated the 7 for a dozen years before retiring it in 1956.
Principal Dimensions by Steve Llanso of Middle Run Media | |||
---|---|---|---|
Class | 25 | 6 | 7 |
Locobase ID | 12065 | 12909 | 5307 |
Railroad | Concord & Montreal (B&M) | Berlin Mills | Berlin Mills |
Country | USA | USA | USA |
Whyte | 2-4-2T | 2-4-2ST | 2-4-2ST |
Number in Class | 1 | 1 | 3 |
Road Numbers | 25/ 725/57 | 6 | 7, 3, 8 |
Gauge | Std | Std | Std |
Number Built | 1 | 1 | 3 |
Builder | Burnham, Williams & Co | Burnham, Williams & Co | Vulcan Foundry |
Year | 1893 | 1906 | 1911 |
Valve Gear | Stephenson | Stephenson | Walschaert |
Locomotive Length and Weight | |||
Driver Wheelbase (ft / m) | 7 / 2.13 | 7 / 2.13 | 7 / 2.13 |
Engine Wheelbase (ft / m) | 22.67 / 6.91 | 22.42 / 6.83 | 22.58 / 6.88 |
Ratio of driving wheelbase to overall engine wheelbase | 0.31 | 0.31 | 0.31 |
Overall Wheelbase (engine & tender) (ft / m) | 22.67 / 6.91 | 22.42 / 6.83 | 22.58 |
Axle Loading (Maximum Weight per Axle) (lbs / kg) | |||
Weight on Drivers (lbs / kg) | 65,000 / 29,484 | 80,000 / 36,287 | 85,000 / 38,555 |
Engine Weight (lbs / kg) | 95,000 / 43,091 | 113,000 / 51,256 | 115,000 / 52,163 |
Tender Loaded Weight (lbs / kg) | |||
Total Engine and Tender Weight (lbs / kg) | |||
Tender Water Capacity (gals / ML) | 1500 / 5.68 | 1800 / 6.82 | 1500 / 5.68 |
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 1.75 / 2 | 2 / 2 | |
Minimum weight of rail (calculated) (lb/yd / kg/m) | 54 / 27 | 67 / 33.50 | 71 / 35.50 |
Geometry Relating to Tractive Effort | |||
Driver Diameter (in / mm) | 44 / 1118 | 44 / 1118 | 44 / 1118 |
Boiler Pressure (psi / kPa) | 170 / 1170 | 175 / 1210 | 140 / 1310 |
High Pressure Cylinders (dia x stroke) (in / mm) | 16" x 24" / 406x610 | 16" x 22" / 406x559 | 17" x 24" / 432x610 |
Tractive Effort (lbs / kg) | 20,177 / 9152.14 | 19,040 / 8636.41 | 18,759 / 8508.95 |
Factor of Adhesion (Weight on Drivers/Tractive Effort) | 3.22 | 4.20 | 4.53 |
Heating Ability | |||
Tubes (number - dia) (in / mm) | 175 - 2" / 51 | 180 - 2" / 51 | 186 - 2" / 51 |
Flues (number - dia) (in / mm) | |||
Flue/Tube length (ft / m) | 10.83 / 3.30 | 10.58 / 3.30 | 12.33 / 3.76 |
Firebox Area (sq ft / m2) | 77.70 / 7.22 | 112 / 10.41 | |
Grate Area (sq ft / m2) | 14.40 / 1.34 | 14.30 / 1.33 | 22.50 / 2.09 |
Evaporative Heating Surface (sq ft / m2) | 1062 / 98.70 | 1102 / 102.38 | |
Superheating Surface (sq ft / m2) | |||
Combined Heating Surface (sq ft / m2) | 1062 / 98.70 | 1102 / 102.38 | |
Evaporative Heating Surface/Cylinder Volume | 189.98 | 215.23 | |
Computations Relating to Power Output (More Information) | |||
Robert LeMassena's Power Computation | 2448 | 2503 | 3150 |
Same as above plus superheater percentage | 2448 | 2503 | 3150 |
Same as above but substitute firebox area for grate area | 13,209 | 19,600 | |
Power L1 | 3235 | 4166 | |
Power MT | 219.44 | 229.61 |