Jim Smellie's article on this class appears as part of a series carried on a brass-locomotive modeling site -- [] (visited 13 May 2003).
These were developed by John F. McIntosh to cope with the "closely spaced stations, steep gradients, and tight curves" of Glasgow's Cathcart Circle and Edinburgh's Balerno Branch. His design combined elements of several earlier classes (see Smellie for details) into a compact and efficient-looking engine.
Locomotives orbited the Cathcart Circle, never having to reverse direction. The 104s were responsible for virtually all of Edinburgh's Balerno and Barnton-branch passenger service until well into the 1930s. Most were soon withdrawn, however, once the LMS strengthened the line to allow larger engines. Even though their service was in most cases limited to less than 40 years, several in the class amassed more than 1 million miles of operation each.
Data from "Old Tank Locomotive, Caledonian Railway," The Locomotive Magazine, Vol IX (14 November 1903), p. 282. Works numbers were 1775-1776, 1937-1938
Benjamin Connor ordered this quartet, whose design introduced the 4-wheel bogie truck to the Caledonian. The LM report notes that visually "...it will be noticed that the engines more closely resembled those which were used on the Elevated Ry [sic] of New York than any running in this country."
488 worked first in Perth, while 489 went to Stirling, and 490-491 served Leith. 488-489 later hauled commuter traffic from Edinburgh to Balerno. They continued into the 20th Century.
Data from "Condensing Tank Locomotive for the Caledonian Railway," The Locomotive & Railway Carriage & Wagon Review, Vol III (September 1898), p. 135.
Designed to work the underground portions of the Glasgow ...uh ...underground, these had condensing tanks were supposed to swallow their exhaust and pass it back to the tanks.
How successful that was is shown in this excerpt quoted by Steamindex -- [], last accessed 11 April 2009 -- from Cox's Chronicles of steam:
"My uncle lived on one of the routes served by the Caledonian from Central Low Level Station, and how can I forget the descent from the lofty and in those days immaculate spaces of the main-line station into the murky depths of this steam-operated underground. A permanent woolly pall of steam clung under the low roof on the platforms whence drops of dirty moisture descended upon the waiting passengers; 0-4-4 condensing Tank engines rather sensibly painted black operated the service ... Conditions underground were really rather frightful but how fascinating it all was and to the best of my knowledge this inferno continued unabated into quite recent times"
Principal Dimensions by Steve Llanso of Middle Run Media | |||
---|---|---|---|
Class | 104 | 488 / 1350 / 1167 | 92 |
Locobase ID | 5530 | 10403 | 10101 |
Railroad | Caledonian | Caledonian | Caledonian |
Country | Great Britain | Great Britain | Great Britain |
Whyte | 0-4-4T | 0-4-4T | 0-4-4T |
Number in Class | 12 | 4 | 12 |
Road Numbers | 104-111, 167-170 | 488-491 / 1350-1353 / 1167-1170 | 92-103 |
Gauge | Std | Std | Std |
Number Built | 12 | 4 | 12 |
Builder | St. Rollox | Neilson & Co | St. Rollox |
Year | 1899 | 1873 | 1897 |
Valve Gear | Stephenson | Stephenson | Stephenson |
Locomotive Length and Weight | |||
Driver Wheelbase (ft / m) | 7.50 / 2.29 | 5.75 / 1.75 | 7.50 / 2.29 |
Engine Wheelbase (ft / m) | 20.50 / 6.25 | 20.75 / 6.32 | 22 / 6.71 |
Ratio of driving wheelbase to overall engine wheelbase | 0.37 | 0.28 | 0.34 |
Overall Wheelbase (engine & tender) (ft / m) | 20.50 / 6.25 | 22 / 6.71 | |
Axle Loading (Maximum Weight per Axle) (lbs / kg) | 39,284 / 17,819 | ||
Weight on Drivers (lbs / kg) | 71,680 / 32,514 | 86,912 / 39,423 | |
Engine Weight (lbs / kg) | 114,520 / 51,945 | 120,512 / 54,663 | |
Tender Loaded Weight (lbs / kg) | |||
Total Engine and Tender Weight (lbs / kg) | 114,520 / 51,945 | 120,512 / 54,663 | |
Tender Water Capacity (gals / ML) | 1200 / 4.55 | 1200 / 4.55 | |
Tender Fuel Capacity (oil/coal) (gals/tons / Liters/MT) | 2.50 / 2 | ||
Minimum weight of rail (calculated) (lb/yd / kg/m) | 60 / 30 | 72 / 36 | |
Geometry Relating to Tractive Effort | |||
Driver Diameter (in / mm) | 54 / 1372 | 54 / 1372 | 69 / 1753 |
Boiler Pressure (psi / kPa) | 150 / 1030 | 140 / 970 | 150 / 1030 |
High Pressure Cylinders (dia x stroke) (in / mm) | 17" x 24" / 432x610 | 17" x 22" / 432x559 | 18" x 26" / 457x660 |
Tractive Effort (lbs / kg) | 16,377 / 7428.49 | 14,011 / 6355.29 | 15,566 / 7060.63 |
Factor of Adhesion (Weight on Drivers/Tractive Effort) | 4.38 | 5.58 | |
Heating Ability | |||
Tubes (number - dia) (in / mm) | 206 - 1.75" / 44 | - 1.75" / 44 | |
Flues (number - dia) (in / mm) | |||
Flue/Tube length (ft / m) | 10.33 / 3.15 | 10.04 / 3.06 | |
Firebox Area (sq ft / m2) | 110.90 / 10.31 | 83 / 7.71 | |
Grate Area (sq ft / m2) | 17 / 1.58 | 13 / 1.21 | |
Evaporative Heating Surface (sq ft / m2) | 1086 / 100.93 | 785 / 72.96 | |
Superheating Surface (sq ft / m2) | |||
Combined Heating Surface (sq ft / m2) | 1086 / 100.93 | 785 / 72.96 | |
Evaporative Heating Surface/Cylinder Volume | 172.24 | 135.82 | |
Computations Relating to Power Output (More Information) | |||
Robert LeMassena's Power Computation | 2550 | 1820 | |
Same as above plus superheater percentage | 2550 | 1820 | |
Same as above but substitute firebox area for grate area | 16,635 | 11,620 | |
Power L1 | 3513 | 2616 | |
Power MT | 216.09 |