Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 24, p.9. Thanks to Chris Hohl for his 2 April 2021 email correcting the driver diameter and boiler pressure.)
Works number was 18977 in May 1901.
Either express passenger traffic between Montreal and Ottawa increased rapidly or the Vauclain-compound Atlantics delivered to predecessor Ottawa, Amprior & Perry Sound in 1899 failed to meet their guarantees (Locobase 12356). In any event, the CAR went back to Baldwin to order a single example of an enlarged version that was "Guaranteed to develop a speed 12% greater ...or 12% greater hauling capacity at the same speed" as the earlier engines.
Baldwin took a curious approach in meeting the request when it increased grate and heating surface areas, but also increased the size of the drivers. Although 4 fewer in number, each fire tube was 12" (305 mm) longer than those of the 619 and thus nearly possessing the ideal length/diameter ratio then thought to be a key value.
The design seems clearly to be based on the Burlington's P-1-C of 1899 (Locobase 369). At any rate, the firebox, grate, cylinders, and driver diameters were identical as were the wheelbases and the weights were quite close.
It's unlikely that the railway was entirely satisfied as this was the last Atlantic procured. It was never converted to single-expansion by either the CAR or Grand Trunk and went to the ferro-knacker in April 1917.
| Principal Dimensions by Steve Llanso of Middle Run Media | |
|---|---|
| Class | 618/B |
| Locobase ID | 12357 |
| Railroad | Canada Atlantic (GTR) |
| Country | Canada |
| Whyte | 4-4-2 |
| Number in Class | 1 |
| Road Numbers | 618/1334/1502 |
| Gauge | Std |
| Number Built | 1 |
| Builder | Burnham, Williams & Co |
| Year | 1901 |
| Valve Gear | Stephenson |
| Locomotive Length and Weight | |
| Driver Wheelbase (ft / m) | 7.50 / 2.29 |
| Engine Wheelbase (ft / m) | 27.08 / 8.25 |
| Ratio of driving wheelbase to overall engine wheelbase | 0.28 |
| Overall Wheelbase (engine & tender) (ft / m) | 55.37 / 16.88 |
| Axle Loading (Maximum Weight per Axle) (lbs / kg) | |
| Weight on Drivers (lbs / kg) | 86,030 / 39,023 |
| Engine Weight (lbs / kg) | 168,910 / 76,616 |
| Tender Loaded Weight (lbs / kg) | 133,000 / 60,328 |
| Total Engine and Tender Weight (lbs / kg) | 301,910 / 136,944 |
| Tender Water Capacity (gals / ML) | 7000 / 26.52 |
| Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | |
| Minimum weight of rail (calculated) (lb/yd / kg/m) | 72 / 36 |
| Geometry Relating to Tractive Effort | |
| Driver Diameter (in / mm) | 84.25 / 2140 |
| Boiler Pressure (psi / kPa) | 210 / 1450 |
| High Pressure Cylinders (dia x stroke) (in / mm) | 13.5" x 26" / 343x660 |
| Low Pressure Cylinders (dia x stroke) (in / mm) | 23" x 26" / 584x660 |
| Tractive Effort (lbs / kg) | 14,934 / 6773.96 |
| Factor of Adhesion (Weight on Drivers/Tractive Effort) | 5.76 |
| Heating Ability | |
| Tubes (number - dia) (in / mm) | 258 - 2" / 51 |
| Flues (number - dia) (in / mm) | |
| Flue/Tube length (ft / m) | 16 / 4.88 |
| Firebox Area (sq ft / m2) | 186 / 17.28 |
| Grate Area (sq ft / m2) | 33.60 / 3.12 |
| Evaporative Heating Surface (sq ft / m2) | 2336 / 217.02 |
| Superheating Surface (sq ft / m2) | |
| Combined Heating Surface (sq ft / m2) | 2336 / 217.02 |
| Evaporative Heating Surface/Cylinder Volume | 542.34 |
| Computations Relating to Power Output (More Information) | |
| Robert LeMassena's Power Computation | 7056 |
| Same as above plus superheater percentage | 7056 |
| Same as above but substitute firebox area for grate area | 39,060 |
| Power L1 | 7703 |
| Power MT | 394.80 |