Boston & Lowell / Boston & Maine / Cheshire / Concord / Concord & Montreal / Connecticut River / Fitchburg / Portland & Rochester 4-6-0 "Ten-Wheeler" Locomotives in the USA


Class Details by Steve Llanso of Sweat House Media

Class 1057/C-20 (Locobase 12425)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 23, p. 59. Works numbers were 17926-17928, 17959 in July 1900.

These four freight-hauling Ten-wheelers were ordered by the Fitchburg, but that railroad was taken over by the Boston & Maine before any of them were delivered. Reflecting the western Massachusetts operating territory, the design had the low drivers and the specific stipulations that the clearance diagram had include the ability to "get through Hoosac Tunnel."

All served the B & M until the late 20s and were scrapped between March and November 1928.


Class 16/C (Locobase 16208)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 1332 in August 1887 and 1397 in August 1888.

Although produced to essentially the same design in the late 1880s, this pair diverged in some respects when profiled in the 1919 Locomotive Class book. The book shows 51" wheel centers for the 719 and 48" for the 716, 212 tube in the 19's boiler and 210 in the 16.

Both were scrapped in March 1916.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.


Class 3/C (Locobase 16206)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange; Harry A Frye, Minuteman steam: Boston & Maine steam locomotives, 1911-1958 (Littleton, MA : Boston and Maine Railroad Historical Society, 1982), p. 71. See also Annual Report of the Railroad Commissioners of the State of Maine 1884 (Augusta, Me: Sprague & Son, 1884), p. 28. Works number was 1628 in January 1885.

The P&R connected Maine's seacoast city of Portland with Rochester, NH. Maine hosted most of the mileage (49.5 of the 52 miles/80 of 84 km). Reporting on the P&R's state in 1884, just before the road bought this single Ten-wheeler, the Commissioners noted with pleasure that many upgrades to equipment, structures, and right of way meant "the entire road presents a greatly improved appearance, as compared with its condition in former years." They observed, however, that "the business requires additional engines and several new passenger and freight cars."

The 3 wasn't likely to break much new ground. Its boiler was about as big as its small grate could heat, constrained as was the latter by its position between the two rear sets of drivers.

The Boston & Maine merged with the P&R in January 1900. A later report by the Commissioners noted a big moment: "Since its purchase its [the P&R] use has been changed from that of a local railroad, not requiring a high standard of construction and maintenance, into an important link in one of the Company's principal through lines for the transportation of a large and increasing volume of passenger and freight traffic between the State of Maine and the West and South. This radical change in its traffic conditions makes advisable an immediate expenditure upon it of a sum sufficient to raise the standard of its usefulness to the level of its present and prospective traffic requirements."

It's doubtful that the 3, renumbered three times and finally given 1922, contributed to this main-line tranformation, but it soldiered on until May 1916.


Class 302/C-14 (Locobase 10870)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 3383-3386 in January-February 1891.

This quartet of Ten-wheelers were the first in the B&M system to use a 41" (1,041 mm) wide grate and thus increase their grate areas considerably while permitting a more evenly spaced set of driving axles.

But they may have been too heavy for the light duty to which they would have been delegated. In any event, the four were scrapped between February 1912 and June 1916.


Class 33 (Locobase 16205)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange; Harry A Frye, Minuteman steam: Boston & Maine steam locomotives, 1911-1958 (Littleton, MA : Boston and Maine Railroad Historical Society, 1982), p. 71. See also Annual Report of the Railroad Commissioners of the State of New Hampshire 1887, Volume 43 (Manchester, NH: John B Clarke, Public Printer, 1887), p. 75. Works number was 1008 in May 1881.

This single Ten-wheeler was delivered to the Cheshire Raiload with relatively large 19" x 26" cylinders. In 1903, the engine received a new firebox and smaller cylinders as shown above.

A New Hampshire line, the CRR had a long independent history beginning in 1844 as a northward line out of South Ashburnham, Mass. It eventually connected Fitchburg, Mass. with Bellows Falls, VT, about 64 miles (103 km) away. In 1887, New Hampshire's Railroad Commissioners expressed complete satisfaction with this line in a concise word portrait of fundamental railroad values:

"There are no important changes to report on this road, and few are needed. Its veteran superintendent, who was one of its builders, has put upon it the impress of a steady purpose to make it stable, strong, and permanent. Its road-bed is nearly perfect, and the superstructure is first-class; its masonry is solid and enduring"; its bridges sound, safe, and high; its ties in good condition, · about 3,000 to the mile, and in line on one side; its track heavy steel; its ballast fourteen feet wide, deep, and of good material; its ditches well cut and unchoked, and its roadway well grassed and clean. It is free from sharp sags, and its few curves are skillfully drawn, while its stations are commodious and in good repair. The stations south of Keene have been repainted."

Contained in its original charter, however, was the proviso that the Fitchburg Railroad and the Cheshire could be united at any time when the presidents and directors of both companies agreed. That merger became official in October 1890.

After its rebuilding, the 1915 carried on for more than another decade before heading to the scrapyard in April 1916.


Class 46/C (Locobase 16207)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works number was 3820 in April 1892.

Not long after this locomotive rolled onto its rails, the CRRR was credited in a State Commission report with 79.85 miles (129 km) in Massachusetts, 23.21 miles (37.4 km) in New Hampshire, and 0.71 miles (1.1 km) in Vermont. Within a year of its arrival, the 46 had a new number thanks to the Boston & Maine's lease of the CRRTR in 1893.

After it moved onto the B&M roster, the 545 (later the 1984) enjoyed a relatively long career because it sported a good-sized boiler, drivers appropriate for local mixed-traffic service, and decent tractive effort.

1984 came under the ferro-knacker's torch in December 1926.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.


Class 5/C-19 (Locobase 12288)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 21, p. 228. Works number was 16112 in August 1898.

The Fitchburg bought two tall-drivered express engines, one with a Vauclain compound cylinder setup (Locobase 9499), the other with the relatively large cylinders shown here. Each of the locomotives was guaranteed to pull a 325 ton (295.5 tonne) train up a 60-foot (1.1%) grade for 10 miles (16.1 kkm) at 40 mph (64 kph).

For some reason, not long after the Fitchburg quickly converted the #6 to a simple-expansion engine with 19"-diameter cylinders and then were absorbed by the Boston & Maine, the B & M also shrank the diameter of the #313's cylinders to the same figure.

Twenty-two years later in 1924, the B&M updated this engine; see Locobase 16210.


Class 6/C-19a (Locobase 9499)

Data from "Fitchburg Vauclain Compound Passenger Engine," Railway and Locomotive Engineering, February 1899, pp. 72, 74, 83. See also DeGolyer, Volume 21, p. 228+ Works number was 16111 in August 1898.

Like all Vauclain compounds, this single Ten-wheeler had single castings consisting of one high-pressure and one low-pressure cylinder and the associated 13" (330 mm) piston valve, The latter alternately supplied the HP cylinder with live steam and its LP mate with the exhaust. Fitchburg ordered this engine to compare it to an identical single-expansion locomotive shown in Locobase 12288. It was the only Vauclain compound 4-6-0 supplied to the Fitchburg or its succeeding Boston & Maine. (See Locobase 3273 for the ten Schenectady cross-compounds delivered in the same year.)

Each of the locomotives was guaranteed to pull a 325 ton (295.5 tonne) train up a 60-foot (1.1%) grade for 10 miles (16.1 kkm) at 40 mph (64 kph). The specs required a guarantee that the 6 would "with equal or greater efficiency, develop an economy in operation" of at least 10% greater. Should the 6 fail to reach that level, Baldwin was to furnish "free of charge" a set of single-expansion cylinders. Moreover, such a changeover was to "involve as few alterations as possible."

Although highly praised in the article referenced above (as was almost always the case in American railroad journalism at the time), this Vauclain compound may indeed have flunked its test. It discarded its LP cylinders and adopted two 19" x 26" simple-expansion cylinders within three years. By that time, the Fitchburg had come under the Boston & Maine's control, under which the 314 was renumbered 1054, then 2075.

Locobase 16210 describes the makeover of this engine in 1925.


Class C-10 (Locobase 10864)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 1242 in June 1885 and 1253 in December.

These were named Piscutagua and Pautuckaway. After more than three decades, 1927 was scrapped in July 1914 and 1928 was broken up in May 1916.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.


Class C-11 (Locobase 10867)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 1448-1449 in March 1890.

This pair was delivered to the C & M as the General Lafayett and Daniel Weasler. Both received new fireboxes in 1906 and were scrapped in April and March of 1916, respectively.


Class C-12 (Locobase 10868)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 1474 in May 1890, 1475-1477 in June, and 1478-1479 in August.

This sextet of freight Ten-wheelers were delivered with names: Madison, Veteran, Union, Pangos, Merel, and Weedsville. 1946 was scrapped first in August 1914, 1947-1949 were all broken up in April 1916, 1944 in June; for some reason, the aptly named Veteran (now 1945) held on until April 1926.


Class C-13a (Locobase 10858)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 1423-1428.

The names as delivered were Northfield, Woodsville, Boscawen, and Waterloo. The class received new fireboxes in 1901-1904. 1903 was scrapped in February 19112, 1902 (April) and 1904 (May) were broken up in 1916, and 1901 was scrapped in 1924.


Class C-13b (Locobase 10869)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 1293, 1295-1297.

According to the 1919 class list, the engines had different weights and even different wheel diameters..


Class C-15a, C-15b (Locobase 16342)

Data from B&M 1928 Steam Roster Specifications supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange. See also "Ten-wheel Locomotive - Boston & Maine RR", American Engineer, Car Builder and Railroad Journal, Volume 72, No 4 (April 1898), p. 137. Works numbers were 1681-1685 in January 1898, 1686 in February, 1689-1690 in January 1899, 1691-1693 in February, and 1694 in March.

The first six of these locomotives accompanied ten cross-compounds from Schenectady, which are described in Locobase 15821. AERJ reported that the specfications were identical except for the cross-compound vs simple-expansion cylinder layout.

Although 2012's retirement in September 1929 was followed by her sale to the St Johnsbury & Lake Champlain and was to be renumbered 30, she was scrapped instead.


Class C-16 (Locobase 3273)

Data from "Schenectady Compound Ten-Wheelers for the Boston & Maine", Railroad Gazette, Vol XXX [30], No 12 (25 March 1898), p. 217. Works numbers were 4670-4671 in February 1898 in 4711-4718 in March.

A trim-looking cross-compound Ten-wheeler destined to deliver freight service in the White Mountains and and on the Concord branch.

Unlike many compound locomotives that entered US service in the late 1800s and early 1900s, this class remained unconverted to simple expansion for quite a long time.

See Locobase 15821 for the new specifications reflecting the later change.


Class C-16a (Locobase 15821)

Data from B&M 1928 Steam Roster Specifications supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange. (Thanks to Chris Hohl for his 31 December 2014 email pointing out the loaded weight of the tender and its fuel and water capacities.)

Originally delivered in 1898 by Schenectady as cross-compounds (Locobase 3273), this decade of Ten-wheelers received new fireboxes in the late 19aughts. By 1919, the entire class had discarded their unequal cylinders in favor of two 19 x 26 simple-expansion jugs.

Other than the 2035, which was sold to the St Johnsbury & Lamoille County as their 32 in February 1930, all of this class was retired and scrapped in late 1927 (7), 1928 (2), and 1929 (1).


Class C-19b, c (Locobase 16210)

Data from Locomotives and Tenders - Classifications and Descriptions, Boston & Maine Railroad Mechanical Department, 1928 supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange.

These two locomotives had vied with each other in 1895 trials to compare compound vs simple-expansion economy and power. Locobase 9499 shows the Vauclain compound competitor (Fitchburg RR #6) and Locobase 12288 (Fitchburg #5), its simple-expansion competitor. Like most North American compounds, the 6 had quickly jettisoned its two LP cylinders in favor of two 19" x 26" cylinders, which then matched those given to the 5.

Both machines were deemed worthy of an upgrade in the mid-1920s. Both received superheaters, 10" (254 mm) piston valves, and outside radial valve gear.

2075 was dismantled in October 1937 with 2074 following in May 1939.


Class C-21 (Locobase 12517)

Data from B&M 8 - 1919 Locomotive Classification and B&M Locomotive Names and Numbers supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also "Boston & Maine Ten-Wheel Passenger Locomotive," Railway Age, Volume 38, No 20 (11 November 1904), pp. 693-694. Works numbers were 29547-29556 in June 1904, 30567-30574 in June 1905, 39007-39012 and 39599-39600 in May 1906.

It was pretty clear that the Atlantics delivered to the B&M in 1902 may have been fast, but they couldn't haul heavy enough trains for many of the railroad's requirements. So the B&M ordered the Ten-wheelers shown here to be capable of pulling fifteen vestibule cars on either the Eastern or Western Division at an average of 43 mph (69 kph).

Henry Frye, Boston & Maine Railroad Historical Society historian, reported on page 71 of his 1982 compilation of an all-time class list that at some point the C-21s gained the nickname "Grasshoppers". He summarized his research into the reason with "though no one seems to know how or why."


Class C-21 - superheated (Locobase 12518)

Data from B&M 1928 steam roster specifications supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange. See also B&M Locomotive Names and Numbers supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

Locobase 12517 shows this class of Ten-wheelers as they were delivered in 1904.


Class C-3a/C-3c (Locobase 10859)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 1293, 1295-1299 in March 1887.

According to the 1919 class list, the engines had different weights and even different wheel diameters..


Class C-3b (Locobase 10857)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 1386-1389.

The names as delivered were Northfield, Woodsville, Boscawen, and Waterloo. The class received new fireboxes in 1901-1904. 1903 was scrapped in February 19112, 1902 (April) and 1904 (May) were broken up in 1916, and 1901 was scrapped in 1924.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.


Class C-3b (Locobase 10861)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works number was 1444.

Delivered as the Hollis, this engine was given a new firebox in 1899 and ran on the B & M for more than two decades before being scrapped in June 1913.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.


Class C-4 (Locobase 10866)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.


Class C-5 (Locobase 10860)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 1453-1456.

These were delivered to the C & M with these names: Montreal, Dragon, Nashua, and Candia.


Class C-6a (Locobase 10865)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.


Class C-7a (Locobase 10862)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 1523-1524.

The C & M named these two engines the J H Pierson and the Governor Smyth. The 1916 was fitted with a new firebox in 1906; 1917 received its new firebox in 1911. Both were scrapped in 1916, the 1917 in March and 1916 in April.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.


Class C-8 (Locobase 10863)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 1578-1579..

These were similar to the C & M engines shown in Locobase 10862. Both were scrapped in February and March 1916, respectively.

NB: The direct heating surface (including the firebox heating surface) is an estimate calculated by subtracting the calculated tube heating surface from the reported total evaporative heating surface.


Class Monarch/C (Locobase 16204)

Data from B&M 8 - 1919 Loco Class supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange; Harry A Frye, Minuteman steam: Boston & Maine steam locomotives, 1911-1958 (Littleton, MA : Boston and Maine Railroad Historical Society, 1982), p. 71; and an Item in "Science", The Present Age, Volume 3, No 13 (27 March 1884), p. 197.. Works number was 1173 in February 1884.

Like many of the Ten-wheelers of the period, the Monarch had its firebox dropped between the last two driven axles. As a result, the first two adhesive axles were 62" (1,575 mm) apart while the distance to the third from the second was a full 108" (2,743 mm). The Present Age heralded the Monarch as the "largest engine ever built or run in Massachusetts" up to that time.

Principal Dimensions by Steve Llanso of Sweat House Media
Class1057/C-2016/C3/C302/C-1433
Locobase ID12,425 16,208 16,206 10,870 16,205
RailroadBoston & Maine (B&M)Concord (B&M)Portland & Rochester (B&M)Fitchburg (B&M)Cheshire (B&M)
CountryUSAUSAUSAUSAUSA
Whyte4-6-04-6-04-6-04-6-04-6-0
Number in Class42541
Road Numbers1057-1060/2076-207919, 16/719, 716/1940-19413/589/1922302-305/1042-1045/1980-198333/1048/308/1915
GaugeStdStdStdStdStd
Number Built42541
BuilderBurnham, Williams & CoManchesterManchesterSchenectadyRhode Island
Year19001887188518911881
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)15.50 / 4.7214.50 / 4.4214.50 / 4.4212.17 / 3.7115.50 / 4.72
Engine Wheelbase (ft / m)26.08 / 7.9522.50 / 6.8625.92 / 7.90
Ratio of driving wheelbase to overall engine wheebase 0.59 0.54 0.60
Overall Wheelbase (engine & tender) (ft / m)53.08 / 16.1846.67 / 14.23
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)120,000 / 54,43182,000 / 37,19582,000 / 37,19592,000 / 41,73181,800 / 37,104
Engine Weight (lbs / kg)158,000 / 71,668108,000 / 48,988108,000 / 48,988126,000 / 57,153116,000 / 52,617
Tender Loaded Weight (lbs / kg)100,000 / 45,35962,000 / 28,12362,000 / 28,12368,000 / 30,84460,000 / 27,216
Total Engine and Tender Weight (lbs / kg)258,000 / 117,027170,000 / 77,111170,000 / 77,111194,000 / 87,997176,000 / 79,833
Tender Water Capacity (gals / ML)5000 / 18.942900 / 10.983100 / 11.743500 / 13.263500 / 13.26
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT) 6.50 / 5.906 / 5.50 6.50 / 5.90 6.50 / 5.90
Minimum weight of rail (calculated) (lb/yd / kg/m)67 / 33.5046 / 2346 / 2351 / 25.5045 / 22.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)62 / 157555 / 139755 / 139758 / 147358 / 1448
Boiler Pressure (psi / kPa)200 / 13.80145 / 10150 / 10.30155 / 10.70160 / 11
High Pressure Cylinders (dia x stroke) (in / mm)20" x 26" / 508x66019" x 24" / 483x61018" x 24" / 457x61019" x 24" / 483x61018" x 26" / 457x711
Tractive Effort (lbs / kg)28,516 / 12934.6619,415 / 8806.5118,026 / 8176.4719,681 / 8927.1619,753 / 8959.82
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.21 4.22 4.55 4.67 4.14
Heating Ability
Firebox Area (sq ft / m2)205.60 / 19.11124 / 11.52135 / 13.19129 / 11.98146 / 13.56
Grate Area (sq ft / m2)35.20 / 3.2718.70 / 1.7417.50 / 1.6327.60 / 2.5618.90 / 1.76
Evaporative Heating Surface (sq ft / m2)2704 / 251.301590 / 147.711631 / 151.521746 / 162.211489 / 138.33
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)2704 / 251.301590 / 147.711631 / 151.521746 / 162.211489 / 138.33
Evaporative Heating Surface/Cylinder Volume286.02201.88230.74221.69194.45
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation70402712262542783024
Same as above plus superheater percentage70402712262542783024
Same as above but substitute firebox area for grate area41,12017,98020,25019,99523,360
Power L181583730448645494482
Power MT449.63300.85361.83327.03362.39

Principal Dimensions by Steve Llanso of Sweat House Media
Class46/C5/C-196/C-19aC-10C-11
Locobase ID16,207 12,288 9499 10,864 10,867
RailroadConnecticut River (B&M)Fitchburg (B&M)Fitchburg (B&M)Concord & Montreal (B&M)Concord & Montreal (B&M)
CountryUSAUSAUSAUSAUSA
Whyte4-6-04-6-04-6-04-6-04-6-0
Number in Class11122
Road Numbers46/545/19845/313/ 1053/20746/314/1054/207541, 43/741, 743/1927-192858-59 / 758-759 / 1942-1943
GaugeStdStdStdStdStd
Number Built11122
BuilderSchenectadyBurnham, Williams & CoBurnham, Williams & CoManchesterManchester
Year18921898189818851890
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)12 / 3.6614.50 / 4.4214.50 / 4.4213.67 / 4.1715 / 4.57
Engine Wheelbase (ft / m)22.25 / 6.7826.25 / 826.25 / 8
Ratio of driving wheelbase to overall engine wheebase 0.54 0.55 0.55
Overall Wheelbase (engine & tender) (ft / m)53.17
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)103,000 / 46,720111,000 / 50,349111,000 / 50,34977,000 / 34,92788,000 / 39,916
Engine Weight (lbs / kg)130,400 / 59,149145,000 / 65,771150,000 / 68,039104,000 / 47,174116,000 / 52,617
Tender Loaded Weight (lbs / kg)89,000 / 40,37085,000 / 38,55585,000 / 38,55568,000 / 30,84489,000 / 40,370
Total Engine and Tender Weight (lbs / kg)219,400 / 99,519230,000 / 104,326235,000 / 106,594172,000 / 78,018205,000 / 92,987
Tender Water Capacity (gals / ML)4000 / 15.154500 / 17.054500 / 17.053500 / 13.264000 / 15.15
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)7 / 6.40 6.50 / 5.907 / 6.40
Minimum weight of rail (calculated) (lb/yd / kg/m)57 / 28.5062 / 3162 / 3143 / 21.5049 / 24.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)63 / 160078 / 198178 / 198155 / 139766 / 1676
Boiler Pressure (psi / kPa)165 / 11.40200 / 13.80200 / 13.80145 / 10170 / 11.70
High Pressure Cylinders (dia x stroke) (in / mm)19" x 26" / 483x66021" x 26" / 533x66015" x 26" / 381x66019" x 24" / 483x61019" x 24" / 483x610
Low Pressure Cylinders (dia x stroke) (in / mm)25" x 26" / 635x660
Tractive Effort (lbs / kg)20,895 / 9477.8224,990 / 11335.2918,750 / 8504.8719,415 / 8806.5118,969 / 8604.20
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.93 4.44 5.92 3.97 4.64
Heating Ability
Firebox Area (sq ft / m2)132 / 12.26172.37 / 16.02172.37 / 16.01120 / 11.15
Grate Area (sq ft / m2)27.60 / 2.5634.48 / 3.2034.48 / 3.2017.20 / 1.6018.90 / 1.76
Evaporative Heating Surface (sq ft / m2)1961 / 182.182748 / 255.392749 / 255.301520 / 141.211824 / 169.52
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1961 / 182.182748 / 255.392749 / 255.301520 / 141.211824 / 169.52
Evaporative Heating Surface/Cylinder Volume229.84263.65516.94193.00231.60
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation45546896689624943213
Same as above plus superheater percentage45546896689624943213
Same as above but substitute firebox area for grate area21,78034,47434,47417,400
Power L15322900563563578
Power MT341.74536.56378.72307.33

Principal Dimensions by Steve Llanso of Sweat House Media
ClassC-12C-13aC-13bC-15a, C-15bC-16
Locobase ID10,868 10,858 10,869 16,342 3273
RailroadConcord & Montreal (B&M)Boston & Maine (B&M)Boston & Maine (B&M)Boston & Maine (B&M)Boston & Maine (B&M)
CountryUSAUSAUSAUSAUSA
Whyte4-6-04-6-04-6-04-6-04-6-0
Number in Class6641210
Road Numbers749, 800-804 / 1944-1949270-275+ / 1950-1960499-502 / 1961-1964311+/2000-2005, 2010-2012, 2014-2016459-460, 705, 712, 724-725, 731, 771, 774/2030-39
GaugeStdStdStdStdStd
Number Built6641210
BuilderManchesterManchesterManchesterManchesterSchenectady
Year18901889189218981898
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)15 / 4.5715 / 4.5714.17 / 4.3214 / 4.2714 / 4.27
Engine Wheelbase (ft / m)25.46 / 7.7624.29 / 7.4024.42 / 7.4424.42 / 7.44
Ratio of driving wheelbase to overall engine wheebase 0.59 0.58 0.57 0.57
Overall Wheelbase (engine & tender) (ft / m)49.94 / 15.2249.94 / 15.22
Axle Loading (Maximum Weight per Axle) (lbs / kg)34,333 / 15,573
Weight on Drivers (lbs / kg)88,000 / 39,91688,000 / 39,91689,000 / 40,370103,000 / 46,720103,000 / 46,720
Engine Weight (lbs / kg)116,000 / 52,617117,000 / 53,070116,000 / 52,617141,000 / 63,957141,000 / 63,957
Tender Loaded Weight (lbs / kg)68,000 / 30,84468,000 / 30,84470,000 / 31,75289,000 / 40,37089,000 / 40,370
Total Engine and Tender Weight (lbs / kg)184,000 / 83,461185,000 / 83,914186,000 / 84,369230,000 / 104,327230,000 / 104,327
Tender Water Capacity (gals / ML)3500 / 13.263500 / 13.263500 / 13.264000 / 15.154000 / 15.15
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT) 6.50 / 5.90 6.50 / 5.90 6.50 / 5.908 / 7.308 / 7.30
Minimum weight of rail (calculated) (lb/yd / kg/m)49 / 24.5049 / 24.5049 / 24.5057 / 28.5057 / 28.50
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)58 / 147359 / 149957 / 144863 / 160063 / 1600
Boiler Pressure (psi / kPa)150 / 10.30150 / 10.30145 / 10180 / 12.40200 / 13.80
High Pressure Cylinders (dia x stroke) (in / mm)19" x 24" / 483x61019" x 26" / 483x66019" x 26" / 483x66019" x 26" / 483x66021" x 26" / 533x660 (1)
Low Pressure Cylinders (dia x stroke) (in / mm)32" x 26" / 813x660 (1)
Tractive Effort (lbs / kg)19,046 / 8639.1320,283 / 9200.2220,295 / 9205.6722,795 / 10339.6521,626 / 9809.40
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.62 4.34 4.39 4.52 4.76
Heating Ability
Firebox Area (sq ft / m2)141.40 / 13.14141.40 / 13.14
Grate Area (sq ft / m2)18.90 / 1.7618.90 / 1.7618.90 / 1.7627.39 / 2.5427.39 / 2.54
Evaporative Heating Surface (sq ft / m2)1746 / 162.271997 / 185.531994 / 185.25
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1746 / 162.271997 / 185.531994 / 185.25
Evaporative Heating Surface/Cylinder Volume221.69234.06382.62
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation28352835274149305478
Same as above plus superheater percentage28352835274149305478
Same as above but substitute firebox area for grate area25,45228,280
Power L159904687
Power MT384.63300.96

Principal Dimensions by Steve Llanso of Sweat House Media
ClassC-16aC-19b, cC-21C-21 - superheatedC-3a/C-3c
Locobase ID15,821 16,210 12,517 12,518 10,859
RailroadBoston & Maine (B&M)Boston & Maine (B&M)Boston & Maine (B&M)Boston & Maine (B&M)Boston & Lowell (B&M)
CountryUSAUSAUSAUSAUSA
Whyte4-6-04-6-04-6-04-6-04-6-0
Number in Class10224245
Road Numbers2030-20392074-20752100-21232100-2123181, 186-189/402, 407-410/1905-1909
GaugeStdStdStdStdStd
Number Built245
BuilderB&MB&MAlco-SchenectadyB&MManchester
Year19111924190419141887
Valve GearStephensonWalschaertStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)14 / 4.2714.50 / 4.4215.83 / 4.8215.83 / 4.8214.17 / 4.32
Engine Wheelbase (ft / m)24.58 / 7.4926.25 / 826.83 / 8.1826.83 / 8.1824.29 / 7.40
Ratio of driving wheelbase to overall engine wheebase 0.57 0.55 0.59 0.59 0.58
Overall Wheelbase (engine & tender) (ft / m)49.94 / 15.2254.57 / 16.6354.57 / 16.63
Axle Loading (Maximum Weight per Axle) (lbs / kg)34,333 / 15,57344,000 / 19,958
Weight on Drivers (lbs / kg)103,000 / 46,720114,800 / 52,072132,000 / 59,874132,000 / 59,87480,000 / 36,287
Engine Weight (lbs / kg)141,000 / 63,957166,400 / 75,478177,000 / 80,286177,000 / 80,286106,000 / 48,081
Tender Loaded Weight (lbs / kg)89,00085,000 / 38,555115,000 / 52,163115,000 / 52,16368,000 / 30,844
Total Engine and Tender Weight (lbs / kg)230,000251,400 / 114,033292,000 / 132,449292,000 / 132,449174,000 / 78,925
Tender Water Capacity (gals / ML)4000 / 15.154500 / 17.055000 / 18.945000 / 18.943500 / 13.26
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT)7 / 7.3012 / 10.9012 / 10.90 6.50 / 5.90
Minimum weight of rail (calculated) (lb/yd / kg/m)57 / 28.5064 / 3273 / 36.5073 / 36.5044 / 22
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)63 / 160069 / 175372 / 182973 / 182955 / 1397
Boiler Pressure (psi / kPa)180 / 12.40180 / 12.40200 / 13.80200 / 13.80145 / 10
High Pressure Cylinders (dia x stroke) (in / mm)19" x 26" / 483x66020" x 26" / 508x66020" x 26" / 508x66020" x 26" / 508x66018" x 24" / 457x610
Tractive Effort (lbs / kg)22,795 / 10339.6523,061 / 10460.3124,556 / 11138.4324,219 / 10985.5717,425 / 7903.86
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.52 4.98 5.38 5.45 4.59
Heating Ability
Firebox Area (sq ft / m2)144.50 / 13.42158 / 14.68177 / 16.44186.90 / 17.36
Grate Area (sq ft / m2)28 / 2.6035.30 / 3.2844 / 4.0946.27 / 4.3018.70 / 1.74
Evaporative Heating Surface (sq ft / m2)1997 / 185.531839 / 170.852819 / 261.892008 / 186.551678 / 155.89
Superheating Surface (sq ft / m2)400 / 37.16400 / 37.16
Combined Heating Surface (sq ft / m2)1997 / 185.532239 / 208.012819 / 261.892408 / 223.711678 / 155.89
Evaporative Heating Surface/Cylinder Volume234.06194.52298.18212.40237.39
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation50406354880092542712
Same as above plus superheater percentage50407498880010,8272712
Same as above but substitute firebox area for grate area26,01033,55935,40043,735
Power L1602413,639940316,840
Power MT386.81785.77471.14843.77

Principal Dimensions by Steve Llanso of Sweat House Media
ClassC-3bC-3bC-4C-5C-6a
Locobase ID10,857 10,861 10,866 10,860 10,865
RailroadBoston & Maine (B&M)Boston & Maine (B&M)Boston & Maine (B&M)Concord & Montreal (B&M)Boston & Maine (B&M)
CountryUSAUSAUSAUSAUSA
Whyte4-6-04-6-04-6-04-6-04-6-0
Number in Class41342
Road Numbers256-259 / 1901-1904232 / 1900457-458, 469 / 1931-193354-57/754-757/1910-1913395-396/ 1925-1926
GaugeStdStdStdStdStd
Number Built41342
BuilderManchesterManchesterRhode IslandManchesterSchenectady
Year18881890189118891886
Valve GearStephensonStephensonStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)15 / 4.5715 / 4.5714.42 / 4.4015 / 4.5710.50 / 3.20
Engine Wheelbase (ft / m)20.33 / 6.20
Ratio of driving wheelbase to overall engine wheebase 0.52
Overall Wheelbase (engine & tender) (ft / m)
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)80,000 / 36,28780,000 / 36,28790,000 / 40,82382,000 / 37,19586,000 / 39,009
Engine Weight (lbs / kg)106,000 / 48,081106,000 / 48,081110,000 / 49,895108,000 / 48,988112,000 / 50,802
Tender Loaded Weight (lbs / kg)68,000 / 30,84462,000 / 28,12366,000 / 29,93760,000 / 27,21662,000 / 28,123
Total Engine and Tender Weight (lbs / kg)174,000 / 78,925168,000 / 76,204176,000 / 79,832168,000 / 76,204174,000 / 78,925
Tender Water Capacity (gals / ML)3500 / 13.262100 / 7.953400 / 12.882900 / 10.982900 / 10.98
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT) 6.50 / 5.906 / 5.506 / 5.50 6.50 / 5.906 / 5.50
Minimum weight of rail (calculated) (lb/yd / kg/m)44 / 2244 / 2250 / 2546 / 2348 / 24
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)54 / 137254 / 137254 / 137254 / 137254 / 1372
Boiler Pressure (psi / kPa)150 / 10.30140 / 9.70150 / 10.30145 / 10150 / 10.30
High Pressure Cylinders (dia x stroke) (in / mm)18" x 24" / 457x61018" x 24" / 457x61018" x 24" / 457x61018" x 24" / 457x61018" x 24" / 457x610
Tractive Effort (lbs / kg)18,360 / 8327.9717,136 / 7772.7718,360 / 8327.9717,748 / 8050.3718,360 / 8327.97
Factor of Adhesion (Weight on Drivers/Tractive Effort) 4.36 4.67 4.90 4.62 4.68
Heating Ability
Firebox Area (sq ft / m2)140 / 13.01112.50 / 10.46143.50 / 13.34126 / 11.71
Grate Area (sq ft / m2)18.90 / 1.7618.70 / 1.7419.10 / 1.7818.90 / 1.7622.80 / 2.12
Evaporative Heating Surface (sq ft / m2)1530 / 142.191516 / 140.891478 / 137.361405 / 130.581641 / 152.51
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1530 / 142.191516 / 140.891478 / 137.361405 / 130.581641 / 152.51
Evaporative Heating Surface/Cylinder Volume216.45214.47209.09198.77232.15
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation28352618286527413420
Same as above plus superheater percentage28352618286527413420
Same as above but substitute firebox area for grate area21,00015,75021,52518,900
Power L14259370541934337
Power MT352.11306.30308.13333.54

Principal Dimensions by Steve Llanso of Sweat House Media
ClassC-7aC-8Monarch/C
Locobase ID10,862 10,863 16,204
RailroadConcord & Montreal (B&M)Boston & Maine (B&M)Boston & Lowell (B&M)
CountryUSAUSAUSA
Whyte4-6-04-6-04-6-0
Number in Class225
Road Numbers105-106 / 805-806 / 1916-1917503-504 / 1920-192181/381/1914
GaugeStdStdStd
Number Built225
BuilderManchesterManchesterManchester
Year189118931884
Valve GearStephensonStephensonStephenson
Locomotive Length and Weight
Driver Wheelbase (ft / m)15 / 4.5715 / 4.5715 / 4.57
Engine Wheelbase (ft / m)25.50 / 7.77
Ratio of driving wheelbase to overall engine wheebase 0.59
Overall Wheelbase (engine & tender) (ft / m)
Axle Loading (Maximum Weight per Axle) (lbs / kg)
Weight on Drivers (lbs / kg)88,000 / 39,91682,000 / 37,19583,200 / 37,739
Engine Weight (lbs / kg)117,000 / 53,070108,000 / 48,988108,400 / 49,169
Tender Loaded Weight (lbs / kg)68,000 / 30,84462,000 / 28,12360,000 / 27,216
Total Engine and Tender Weight (lbs / kg)185,000 / 83,914170,000 / 77,111168,400 / 76,385
Tender Water Capacity (gals / ML)3500 / 13.263100 / 11.743500 / 13.26
Tender Fuel Capacity (oil/coal) (gals/tons / ML/MT) 6.50 / 5.906 / 5.50 6.50 / 5.90
Minimum weight of rail (calculated) (lb/yd / kg/m)49 / 24.5046 / 2346 / 23
Geometry Relating to Tractive Effort
Driver Diameter (in / mm)63 / 160066 / 167655 / 1397
Boiler Pressure (psi / kPa)160 / 11150 / 10.30145 / 10
High Pressure Cylinders (dia x stroke) (in / mm)18" x 24" / 457x61018" x 24" / 457x61018" x 24" / 457x610
Tractive Effort (lbs / kg)16,786 / 7614.0115,022 / 6813.8717,425 / 7903.86
Factor of Adhesion (Weight on Drivers/Tractive Effort) 5.24 5.46 4.77
Heating Ability
Firebox Area (sq ft / m2)150 / 13.94129 / 11.99142 / 13.19
Grate Area (sq ft / m2)18.90 / 1.7620.20 / 1.8819 / 1.77
Evaporative Heating Surface (sq ft / m2)1920 / 178.441755 / 163.101744 / 162.02
Superheating Surface (sq ft / m2)
Combined Heating Surface (sq ft / m2)1920 / 178.441755 / 163.101744 / 162.02
Evaporative Heating Surface/Cylinder Volume271.62248.28246.73
Computations Relating to Power Output (More Information)
Robert LeMassena's Power Computation302430302755
Same as above plus superheater percentage302430302755
Same as above but substitute firebox area for grate area24,00019,35020,590
Power L1634656024614
Power MT476.95451.84366.78

All material Copyright © SteamLocomotive.com
Wes Barris