Baltimore & Ohio 4-2-0 "Jervis" Locomotives in the USA


Class Details by Steve Llanso of Sweat House Media

Class Lafayette (Locobase 2542)

Data from "Old Time Locomotive Performances", Railway Age, Volume 22 (25 December 1896), pp. 507-508.

Based on the Philadelphia & Columbia's Washington County Farmer, this engine was a typical William Norris design. It had the Bury "haystack" boiler, a bar (vs plate) frame, and a valve gear that was cam-operated. Hollingsworth (1982) notes that later engines in the class had a more typical "gab" motion.

Hollingsworth contends that these engines were a great success, being reliable and showing markedly reduced fuel consumption. William Norris, whose 3 April 1837 report on his locomotives is reproduced in the 1896 article, certainly agreed. He described in detail tests that demonstrated pulling power that he claimed was typical of every-day results: "The La Fayette is performing daily on the Columbia railway, and any persons can, at any time, see for themselves the immense powers of this engine. She drags with ease 25 loaded cars, over abrupt curves and high grades, and on a rise of 52 feet per mile, with the actual weight of 241,275 pounds [120.6 short tons or 109.4 metric tonnes] (taken from the weighmaster's books), attached to her; she has come to a dead stand, and started again without the least difficulty in a state of rest. On Friday last, March 31, this engine brought in, attached to her, the unprecedented and enormous load of 45 cars, 25 of which were loaded, and this load she carried over the grade of 52 feet rise per mile, without any difficulty, not a single instant's delay, but steadily at the rate of nearly 9 miles per hour [14.5 kph]."

With reason, Norris closed by challenging: "Let unbelievers come and see for themselves."

Specifications by Steve Llanso of Sweat House Media
ClassLafayette
Locobase ID2542
RailroadBaltimore & Ohio (B&O)
CountryUSA
Whyte4-2-0
Number in Class8
Road Numbers
GaugeStd
Number Built8
BuilderWilliam Norris
Year1837
Valve Gear
Locomotive Length and Weight
Driver Wheelbase (ft / m)
Engine Wheelbase (ft / m)
Ratio of driving wheelbase to overall engine wheebase
Overall Wheelbase (engine & tender) (ft / m)30.27 / 9.23
Axle Loading (Maximum Weight per Axle) (lbs / kg)11,375 / 5080
Weight on Drivers (lbs / kg)11,375 / 5080
Engine Weight (lbs / kg)18,725 / 19,958
Tender Loaded Weight (lbs / kg)
Total Engine and Tender Weight (lbs / kg)
Tender Water Capacity (gals / ML)540 / 2.05
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT) 1.10 / 1
Minimum weight of rail (calculated) (lb/yd / kg/m)19 / 9.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)48 / 1219
Boiler Pressure (psi / kPa)60 / 4.10
High Pressure Cylinders (dia x stroke) (in / mm)10.5" x 18" / 267x457
Tractive Effort (lbs / kg)2109 / 956.63
Factor of Adhesion (Weight on Drivers/Tractive Effort) 5.39
Heating Ability
Firebox Area (sq ft / m2)
Grate Area (sq ft / m2) 8.60 / 0.80
Evaporative Heating Surface (sq ft / m2)394 / 36.62
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)394 / 36.62
Evaporative Heating Surface/Cylinder Volume218.41
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation516
Same as above plus superheater percentage516
Same as above but substitute firebox area for grate area
Power L1
Power MT

Reference