Class 11/211/M-4-a (Locobase 12315)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 22, p. 20. Note on the nickname from "What's in a Name?", Railway and Shipping World, New Series No. 50 (April 1902), p. 137. Works numbers were 16366-16385 in December 1898.

These nineteen Vauclain-compound Consolidations were the first locomotives built to a design that eventually grew to 200. They used 12" (305 mm) piston valves to admit steam to each pair of cylinders. R&SW reported that these engines were called Doukhobors [sic] "after the Russian sect which settled in the Northwest Territories".

Like virtually all North American railroads, the Intercolonial soon converted them to simple-expansion engines. The result appears in Locobase 8090.

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Class 150/L-7-a (Locobase 4563)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 25, p. 205. Works numbers were 21597-21598 in January 1903.

An interesting note in the Baldwin specs underscored the flexible service patterns often found on Cape Gauge railways. "Economy Car Heating Company's equipment for heating by exhaust steam from pump. Complete car heating equipment with Consolidated steam heat." (In other words, a 2-8-0 pulling a rake of passenger carriages was not unheard of.) Cab structures included added bracing to accommodate snow, especially if it lay on the roof.

Operating conditions included 2% ruling grades and relatively mild 14 degree curves.

Both Consolidations in this class operated in Nova Scotia for Reid Newfoundland for almost 30 years before being scrapped in 1934.

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Class 152 / L-7-a (Locobase 8087)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

This design of Cape gauge Consolidations was relatively small as 2-8-0s ran when compared to the Japanese and South American locomotives also found in Locobase. But they had big grates and a high factor of adhesion and served the NFR through its nationalization by the Newfoundland government and its 1949 absorption by the CNR.

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Class 200/L-5-a (Locobase 8085)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange and the DW & P roster hosted on [], accessed 14 January 2007.

Small, low-drivered Consolidations (works #20678-20680) that are shown as having retired in 1934, but 1801's ghost was preserved in the 1953 diagram book. The profile showed a humble, local-drag-freight engine whose appearance was improved by the pair of arched cab windows on each side.

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Class 690 (Locobase 5590)

Data from [] (19 June 2003), Rene Gourley's website describing this Eastern Canadian railway. The specifications were quite extensive and probably came from the Baldwin specification for this order; see the DeGolyer Library's Baldwin Collection, Volume 21, p. 183.

This class of compound Consolidations was delivered in two batches (Baldwin spec #4215 and #4457) of six--690-695/works number 15955-15960 in May 1898--and eight -- 696-703/works number 16937-16940 in July 1899 and 16954-16957 in August. There were few if any differences as delivered.

At the time of the first order, performance required hauling 1,150-1200 short tons of cars up a 1% grade that was combined with curves of 4 1/2 degrees, "Tracks and cars being in good condition". A later account said they could handle 30-35 loaded freight cars.

The PSC was combined with the Ottawa, Arnprior & Renfrew to become the OA&PS. In 1899, soon after these locomotives were delivered, the Canada Atlantic took over the OA&PS. After several more reorganizations and renamings, the Grand Trunk was formed in 1904. (The GT in turn was taken over by the Canadian National in 1923.)

OA & PS engines were renumbered 1362-1275 by the Grand Trunk. When the CN was formed, these became class M-6-a and M-6-b, numbers 1957-1970. By that time some had a simple-expansion arrangement of two 22" x 30" cylinders.

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Class D (Locobase 15672)

Data from DeGolyer, Volume 22, p. 233. Works numbers were 17189-17196 in October 1899, 17276-17277 in December 1899.

Produced at the peak of sales for Vauclain compound engines, this set of ten Consolidations were sold to the Grand Trunk and went to work on the Grand Trunk Pacific's rails in the West.

Before too long, the engines were simpled by removing the Vauclain compound installation; see Locobase 15673.

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Class D10, D12//M-6a/-b (Locobase 15671)

Data from CN Steam Locomotive Diagrams Assorted supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange.

This class originated as Vauclain compounds delivered to the Ottawa, Amprior & Parry Sound in 1898-1899. Some time later, after the class had been taken into the Grand Trunk and were designated D10 or D12 (for no apparent reason), the compounding system was removed in favor of the two simple-expansion cylinders shown in the specs. Still later, the shops fitted all fourteen with superheaters.

When the CN was formed, these became class M-6-a and M-6-b, numbers 1957-1970.

NB: The superheater area is an estimate based on a comparison with other Schmidt Type A superheater installations of the same flue count and length.

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Class D2 (Locobase 10249)

Data from "Locomotives for the Grand Trunk Railway," Canada, 12 January 1907, which reported that the locomotives were scheduled for April and September deliveries, Railroad Gazette, Volume 40, No 4 (26 January 1906), p. 27, and from GT 6 - 1913 Locomotive Descriptions.

The one order was part of a series of orders that covered a five-year period for cross-compound Consolidations from several Alco subsidiaries. So large a number of two-cylinder compounds delivered so relatively late in the North American compound era may have been unequalled by any other single railroad.

Montreal contributed far more than the lion's share as follows:

Works numbers

N-4-a 39548-39562 in August 1906, 40583-40592 in September, 40593-40602 in October, 40603-40611 in November, 40612-40622 in December, and 42331-4234 in March/April 1907.

In the same month of April 1907, Schenectady produced fifteen N-4-e: 42046-42060 and supplied fifteen more in August: 43540-43554.

Montreal resumed in November 1907 with 43150-43164, continued in August 1908 with 45163-45182, and added fifteen in January/February 1910 as 46880-46894

Alco's Brooks Works produced ten N-4-e in March 1911 as 49663-49674.

Schenectady finished the class in November 1911 with N-4-e 50472-50481.

Road numbers in order of works numbers in 1913 were 651-765, 631-650, 616-630, 766-777, 810, 778-787.

It's not clear when the engines were recylindered to two 23" x 32" HP cylinders, but the program probably began not too long after the last one was delivered as a compound. The modified locomotives took Canadian National class N-4-a for an ID. See Locobase 7613 for the superheated version and Locobase 15649 for .

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Class D5, D-11//N-4-a - Tbolt header (Locobase 7613)

Data from GT 2-1944 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

The Grand Trunk bought many of these Consolidations as cross-compounds; see Locobase 10249.

At some later point the class was superheated as shown in the specifications. Valve gear varied according to subclass. By 1944, classes N-4b and e were still credited with Stephenson inside gear, N-4c and N-4d used Walschaert, and N-4fs had Young gear.

Regardless of valve gear, every engine in this class operated into the 1950s on Canadian National. A few lingered into the early 1960s, the last departing in late 1961.

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Class D7/M-7-a (Locobase 15673)

Data from CN Steam Locomotive Diagrams Assorted supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange.

Most Vauclain compound locomotives (such as the class described in Locobase 15672) were rather quickly converted to simple expansion. These engines soon put two simple-expansion cylinders under the smokebox that were supplied through slide valves. But when the Ds' boilers were superheated, their slide valves were converted for 9" (279 mm) piston valves in "universal" steam chests.

NB: The CN diagrams do not give the superheater area for this class. Locobase estimates the area using the exact tube count, diameter, and lengths from the St Louis, Brownsville & Mexico entry at Locobase 7766.

Only one of the ten remained in service for less than 40 years and 1971 came under the scrapper's torch in August 1938. .Seven more went to the ferro-knacker in 1939-1941 followed by 1974 in May 1943 and 1977 in August 1944..

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Class L-6-a (Locobase 8086)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange and the DW & P roster hosted on [], accessed 14 January 2007. Works numbers were 48352-48353.

Small, low-drivered Consolidations that repeated the design of the Rhode Island locomotives of four years earlier (Locobase 8085), but with just a few more square feet of firebox heating surface. Also like those of the L-5 were the arched cab windows. The L-6s were retired in 1933.

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Class M-1-a/-b (Locobase 8088)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

This was a sizable class delivered in only 3 years. The first 15 M-1-a had a few fewer tubes (131) and 4 less sq ft of firebox heating surface area for a total of 1,155.6 sq ft of evaporative heating surface. Of these, some were fitted with 23" cylinders and run at 180 psi.

Most of these engines were fitted with Hungerford-Cameron superheaters and had two more tubes and two more flues. (See Locobase 15660 for a full description of this superheater design.). Only 2011-2015, 2017-2019, 2022-2023, 2026-2028 were fitted with a Schmidt Type A superheater.

Although many other Consolidations would be a bit bigger, this class proved suitable for a wide range of 2-8-0-type tasks and served the Canadian Northern and the Canadian National for decades.

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Class M-2-a (Locobase 8089)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

A year after the Canadian Locomotive Company began delivering M-1 Consolidations (see Locobase 8088), they produced this slightly bigger variant. At the time of delivery, it was a saturated-steam engine as shown in the specs. Unlike many of the other 2-8-0s of similar size, these were never superheated.

For some reason, these didn't endure quite as long as either the M-1 or M-3 2-8-0s, the last one being withdrawn in 1941.

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Class M-3-a/-3-b (Locobase 15669)

Data from the Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

Enlargements of the M-1 Consolidations shown in Locobase 8088, this class was delivered with saturated boilers. Montreal Locomotive's works numbers were 42726-42740 in October 1907, 44576-44584 in June 1908, 44585-44595 in July.

When the time soon came to install superheaters, it appears that the CNor wanted test its own design, the Hungerford-Cameron, against the royalty-burdened Schmidt Type A. 2118 was fitted with the former in December 1912 and 2124 (classified M-3-b) received the latter type in October 1913. (See Locobase 15660 for a full description of the H-C superheater.) Since all of the others in this class were equipped with H-C superheaters from July 1915 to November 1916, the H-C won.

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Class M-3-c (Locobase 15670)

Data from CN Locomotive Diagram Assorted supplied in August 1913 from his extensive collection. Works numbers were 50279-50283 in August 1911.

Dunkirk, New York's Alco subsidiary followed the Canadian lead in producing its quintet for the DW&P, but delivered a bigger boiler. Weight increased, of course. Piston valves measured 12" (305 mm) in diameter. The H-C superheater was developed in the Canadian Northern's Winnipeg shops and these were the first locomotives to be delivered with this type installed.

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Class M-3-d/-3-e (Locobase 4825)

Taken from a website reproduction of the Canadian National's Mechanical Department's drawing of this class and from CN Steam Locomotive Diagrams Assorted supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 1048-1072 in 1912 and 1148-1172 in 1913.

Taken in the CN when that railroad amalgamation was formed after World War I.

They had 12" (305 mm) piston valves. These served branch lines for decades, retiring gradually throughout the 1950s.

NB: The CN diagrams do not give the superheater area for this class. Locobase estimates the area using the exact tube count, diameter, and lengths from the St Louis, Brownsville & Mexico entry at Locobase 7766.

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Class M-4-a through n - simple (Locobase 8090)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

At the turn into the 20th Century, the Intercolonial bought this Consolidation design from several builders - Baldwin first in 1899 as Vauclain compounds (Locobase 12315). The last of these (228) was completed with Cleveland cylinders, which are described in Locobase 4087.

Richmond (works 3158-3167), Manchester (works 1767-1776) and Dickson (works 1208-1213) were delivered in 1901 and later the Canadian Locomotive Company in 1901 (works numbers 500-519 in April), 1903 (522-531), 1904 (532-541), 1906 (701-720), 1908 (789-798), and 1910 (938-947).

The M-4 was a straightforward 2-8-0 with 12" piston valves, a healthy size for this locomotive. There were detail differences (two grate areas only 1/10 of a square foot apart, for example), but most of the main features were identical. Some subclasses had 20" pistons, others 20 1/2", still others 22", but most had the 21" cylinders shown in the specs.

The CGR/CNR later superheated the class to a common standard; see Locobase 8091.

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Class M-4-a through n - superheated (Locobase 8091)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Locobase isn't sure just how many M-4 locomotives were built, but the total runs to at least 150.

As noted in the Locobase 8090 entry covering the original saturated-steam design, the M-4 subclasses differed mostly in detail and these were mostly effaced when the railway began superheating the class. All of the engines conformed to a common tube/flue layout (including the retention of 2 1/4" fire tubes). The variety of cylinder diameters persisted and there were many little differences, but the basic design was clearly satisfactory.

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Class M-5-a (Locobase 8092)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 1027-1031 in 1912.

Most of the CGR's Consolidations were M-4s, which had long, narrow fireboxes and relatively large-diameter fire tubes. The M-5s differed in both of these respects as well as in the superheater elements they used. In place of a firebox that fit between the rear drivers, the five M-5-as produced in 1912 -had a wider firebox riding over the drivers. The firebox heating surface area was virtually identical. Also, in place of the 2 1/4" tubes and 5 1/2" flues of the M-4 conversion, the M-5s were delivered with slightly smaller tubes and flues.

After this first set, later M-5s were a bit bigger; see Locobase 8093.

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Class M-5-b/-c/-d (Locobase 8093)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

After the five M-5-a of 1912 (Locobase 8092) came the next quintet (M-5-b) from CLC (works #1114-1118), which had a few more fire tubes, but somehow the superheater area shrank by 12 sq ft (1.1 sq m). Otherwise the design was little changed.

In the same year, Montreal delivered five more (M-5-c, works #52554-52558) to the same design. The M-5-cs had 23" cylinders, the firebox had 2 fewer sq ft of direct heating surface, but a tiny increase in grate area.

Two years later, Canada Foundry delivered six M-5-d, four more (works numbers 1007-1010) and two more in the following year (1011-1012)

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Class N-1-abc - syphon, Thrubolt (Locobase 8097)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

As noted in Locobase 8095, Locobase 8095-8098 show the four main N-1 Consolidation variations the CNR eventually put into service. The principal differences appear to have lain in the length of the tubes and flues, the presence or absence of thermic syphons, and type of header ("TBolts" and "Thru" bolts) used. (Compared to the Tbolt header, the "Thru-bolt" header provided a greater air space between the saturated and superheated sides of the superheater, which reduced the rapidity of heat transfer and allowed for expansion and contraction.)

This variant had the short tubes, ThruBolts, and smaller syphons. Like all N-1s, this variant served the CNR well into the 1950s and even the early 1960s.

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Class N-1-abc - syphon, Thrubolt (Locobase 8098)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

As noted in Locobase 8095, Locobase 8095-8098 show the four main N-1 Consolidation variations the CNR eventually put into service. The principal differences appear to have lain in the length of the tubes and flues, the presence or absence of thermic syphons, and the type of header ("TBolts" and "Thru-bolts") used. (Compared to the Tbolt header, the "Thru-bolt" header provided a greater air space between the saturated and superheated sides of the superheater, which reduced the rapidity of heat transfer and allowed for expansion and contraction.)

This variant had the short tubes, ThruBolts, and thermic syphons. Like all N-1s, this variant served the CNR well into the 1950s and even the early 1960s.

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Class N-1abc - no syphon, Tbolt (Locobase 8095)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

Locobase 8095-8098 show the four main N-1 Consolidation variations the CNR eventually put into service; the total number was 55 engines. All had 12" (305 mm) piston valves and Walschaert gear. The principal differences appear to have lain in the length of the tubes and flues, the presence or absence of thermic syphons, and the type of bolts in the header ("TBolts" and "Thru" bolts) used.

This variant had the short tubes, TBolts, and the smaller firebox. Like all N-1s, this variant served the CNR well into the 1950s and even the early 1960s.

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Class N-1abc - syphon, TBolt (Locobase 8096)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

As noted in Locobase 8095, Locobase 8095-8098 show the four main N-1 Consolidation variations the CNR eventually put into service. The principal differences appear to have lain in the length of the tubes and flues, the presence or absence of thermic syphons, and type of bolts in the header ("TBolts" and "Thru" bolts) used.

This variant had the long tubes, TBolts, and thermic syphons. Like all N-1s, this variant served the CNR well into the 1950s and even the early 1960s.

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Class N-2-a - Tbolt (Locobase 8099)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 56745-56754.

Delivered to the DW&P as a single batch, this set of Consolidations represented a tweak to the N-1 series (Locobase 8095-8098). Like the N-1s, the N-2s eventually deployed in several different versions. Even this group was subdivided into those with the longer tubes shown in the specs and others with 14' 5" tubes that resulted in a 2,514 sq ft heating surface.

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Class N-2-b - no syphons (Locobase 15674)

Data from the Canadian National Steam Locomotive Assorted diagram supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange. Works numbers were 59410-59446, 59448-59461 in 1918.

The class of fifty large Consolidations supplied by Montreal Locomotive Works ultimately served the CNor and Canadian National in several variations. Some were equipped first with the Canadian Northern's home-grown Hungerford-Cameron superheater (see full details in Locobase 15660). The H-C boilers had tubes and flues measuring 15 feet 2 3/4 inches (4.64 metres). In an H-C boiler, the total evaporative heating surface area with no syphons measured 2,661 sq ft (247.2 sq m).

All N-2-bs sacrificed the H-C in favor of the Schmidt superheater,Thru-bolt types, a modification whose impact was confined primarily to the front tubesheet and smokebox, although the overall length of the tubes and flues decreased by 9 1/4" (235 mm). (Compared to the Tbolt header, the "Thru-bolt" header provided a greater air space between the saturated and superheated sides of the superheater, which reduced the rapidity of heat transfer and allowed for expansion and contraction.)

The result is shown in these specs. N-2-bs 2484, 2486, 2490, 2492, 2494, 2496, 2505, 2508-2509,2511-2514 were converted to oil-firing and given tenders that held 2,960 gallons (3,552 US gallons/13,444 litres) of fuel oil and 7,400 gallons (8,880 US gallons/33,611 litres) of water. These weighed 165,150 lb (74,911 kg) fully loaded.

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Class N-2-b - syphons (Locobase 8100)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

Locobase 8099 shows the DW & P N-2 engines with Schmidt superheaters. The current entry shows one of the several variants that were first fitted with Hungerford-Cameron superheaters (see full description of this superheater at Locobase 15660). The H-C boilers had tubes and flues measuring 15 feet 2 3/4 inches (4.64 metres).

Some had thermic syphons, such as the engine shown here, which meant a larger firebox heating surface ( see Locobase 15674 for the non-syphon version) and more evaporative heating surface area. In an H-C boiler, the total evaporative heating surface area with syphons measured 2,631 sq ft (244.4 sq m). (Reorganizing the firebox to take syphons meant eliminating ten of the firetubes.)

All of the N-2-bs swapped out their H-Cs for Schmidt Thru-bolt types, a modification whose impact was confined primarily to the front tubesheet and smokebox, although the overall length of the tubes and flues decreased by 9 1/4" (235 mm). (Compared to the Tbolt header, the "Thru-bolt" header provided a greater air space between the saturated and superheated sides of the superheater, which reduced the rapidity of heat transfer and allowed for expansion and contraction.)

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Class N-3-a (Locobase 8101)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

Locobase 8093 shows a light Consolidation that the CGR put into service in 1913. The current entry shows the first five of a larger design that appeared in greater quantities. Montreal's contribution to the N-3 class was limited to this quintet (works #53846-53850).

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Class N-3-b/c/d (Locobase 8102)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

Locobase 8101 describes a set of 5 CGR Consolidations that set the tone for a larger design. CLC took over the contract, enlarged the boiler to take ten more fire tubes. In addition to increasing the evaporative heating surface by 90 sq ft (8.35 sq m), the change resulted in 10 more sq ft (9.3 sq m) of direct heating surface. Firebox heating surface included arch tubes.

CLC delivered 4 batches:

Subclass Year Works numbers Road numbers

N-3-b 1913-1914 1197-1206, 1221-1226 271-286

N-3-c 1915 1254-1268 287-301

N-3-d 1916 1320-1334 302-316

Some later received thermic syphons.

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Class N-4-a - Thru-bolt header (Locobase 15675)

Data from Canadian National Steam Locomotive Assorted diagrams supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange.

Locobase 7613 shows the superheated version of the numerous N-4 class of Consolidations.

Later in their careers, these engines underwent further modification in which their "T-bolt" headers were replaced with "Thru-bolt" headers. Compared to the Tbolts, the "Thru-bolt" header provided a greater air space between the saturated and superheated sides of the superheater, which reduced the rapidity of heat transfer and allowed for expansion and contraction. The shorter tubes and flues reduced evaporative heating surface area by 140sq ft (13 sq m).

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Class N-4-g (Locobase 15649)

Data from Canadian National Steam Locomotive Assorted diagrams supplied in August 2013 by Allen Stanley from his extensive Rail Data Exchange.

This pair was part of a quartet that emerged from the CN's shops in 1926. Montreal originally delivered the pair as cross-compounds to the Grand Trunk to join the large D2 class (Locobase 10249). The first arrived in October 1906, who placed it in the D2 class as 663. The second engine joined the D2 class as 626 in February 1910. The others had 2" (50.8 mm) shorter strokes in the cylinders, were classed as N-5-c, and are shown in Locobase 7501.

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Class N-5-a/-b (Locobase 8103)

Data from CN to 1953 locomotive diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also "Canadian National Locomotives", Canadian Railway and Marine World" (June 1926), pp. 303-304.

Most of the Consolidations to which the Canadian National would fall heir in 1923 had very similar power dimensions (24" x 32"cylinders). The Grand Trunk locomotives had a different setup that used less cylinder volume as shown in the specs. They were also considerably smaller in the boiler, while being slighly larger in the grate. Apparently all were delivered in the configuration, although many were later altered as following Locobases reveal.

About this class, CR&MW's 1926 report provided a very favorable evaluation. For the purposes of serving Alberta's lines, these were "most satisfactory class of power of their size ...they are of rugged construction, with boilers of large capacity for their cylinder size, with wide fireboxes, and have proved to be very economical as concerns maintenance of both boilers and machinery." The 63" drivers proved sufficient to suit them "for either freight or passenger service, as they have enough speed to handle any ordinary passenger train when required."

Even in 1926, they were mainline freight train mainstays, hauling both time and drag freights. One operational factor was the relatively low 0.4% ruling grade, which allowed a tonnage rating of 2,730 "equated" tons.

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Class N-5-a/-b - Tbolt, syphons (Locobase 8105)

Data from CN to 1953 locomotive diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

Modifications to the basic N-5 took many forms. ( See Locobase 8103 for the railway's enthusiastic review of the N-5s qualities and performance.)

One such was relatively simple: modify the firebox to take thermic syphons, which added 36 sq ft to the firebox heating surface. At the same time, the boiler lost 12 fire tubes. Given the usual 6:1 ratio of heating effectiveness (1 sq ft of firebox equalling 6 sq ft of tube), this tradeoff represented a net plus.

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Class N-5-a/-b - Thrubolt, no syphon (Locobase 8104)

Data from CN to 1953 locomotive diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

One variation of the basic N-5 ( See Locobase 8103 for the railway's enthusiastic review of the N-5s qualities and performance) was this design, which featured a "thru-bolt header" for the superheater. (The "Thru-bolt" header provided a greater air space between the saturated and superheated sides of the superheater, which reduced the rapidity of heat transfer and allowed for expansion and contraction.)

Another variant with this tube length included thermic syphons, which added 36 sq ft to the firebox heating surface, but reduced the number of tubes by 12.

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Class N-5-c (Locobase 7501)

Data from [], a website dedicated to the first locomotive built in western Canada (accessed May 2006). See also "Canadian National Locomotives", Canadian Railway and Marine World" (June 1926), pp. 303-304.

The Transcona shops in Alberta delivered this engine in April 1926. CR&MW wrote it was "advised officially" that the pair were the first built in the CNR's own shops and the first built in Western Canada. Fittingly, their construction out of spare parts and components mostly produced on site was overseen by the enterprising shop's General Superintendent of motive power and car equipment named A H Eager.

Part of a continuing series of CN 2-8-0s, this small subclass represented "Old School" in its boiler and superheater layout. See Locobase 8103 for the railway's enthusiastic review of the N-5s qualities and performance.

CNR noted, however, that while the two were "in the main, reproductions" of earlier classes, "all the latest devices have been added to make them thoroughly modern" Updates included the mounting of an Elesco feed water heater. They used the Schmidt through-bolt header (described in Locobase 8104) and supplied steam through 14" (356 mm) piston valves.

Two others with 32" stroke were designated N-4-g and are shown in Locobase 15649.

The very next subclass - N-5-d shown in Locobase 4356 - turned things over as it incorporated the Type E superheater.

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Class N-5-d (Locobase 4356)

Data from the 1953 Canadian National locomotive diagram supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

A boiler pressure that high combined with so high a superheat ratio suggests a demanding maintenance schedule. Note that the boiler had very few small tubes--almost all of the area was in the 3 1/2" flues. The firebox heating surface included thermic syphons.

That these engines stayed in service until the late 1950s (1960 and 1958, respectively) may mean careful husbanding of resources. Their longevity also is attributable to the railway's enthusiastic 1926 review of the N-5s qualities and performance, which is found in Locobase 8103.