Philadelphia & Reading 4-4-0 "American" Locomotives in the USA

Class 1 (Locobase 12245)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 21, p. 109. Works number 15791 in March 1898.

This single locomotive was an inspection engine with cylinders and drivers sized to give adequate speed to a short or non-existent train. Like others of its kind, the #1's cab extended the full length of the boiler to just before the stack. Steps placed on either side of the pilot curved up to the doors that let into a salon lit by a rows of windows and arranged to seat several officers. (Locobase wonders just how hot that compartment became during the locomotive's operation.).

The 101 served the Reading for over three decades before being scrapped in September 1929.

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Class 100 (Locobase 12643)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 25, p. 115. (Thanks to Chris Hohl for his 25 December 2019 email noting the correct boiler pressure.) Works numbers were 21341 in November 1902.

This inspection engine had a "...cab or car body to extend over the body. Car body or cab to be designed & purchased from Jackson & Sharp Co ...[shout out to Wilmington, Del]..." It was later modified as a 4-4-2; see Locobase 14994.

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Class 1015/D5-b (Locobase 3951)

This locomotive is the subject of a Railroad Gazette essay (22 June 1900) entitled "What is the Ideal Passenger Engine" by SM Prince, Jr., Superintendent of Motive Power and Railway Engineering for the Philadelphia & Reading. Baldwin's original works numbers were 9986-9987, 9997, 10001 in May 1889 and 10031-10032 in June.

These engines were originally built in 1889 and rode on 68 1/2" drivers until Prince took them in hand in 1899 to demonstrate his argument.

"I firmly believe this [a high-drivered Camelback with wide Wootten firebox] to be the ideal type of high-speed passenger engine," declared the Super. What is so fascinating about Prince's assertions is how most of them would be overtaken by history, technology, and especially train demands within months rather than years. Prince, for example, asserted that there was no real value to be gained by adding a trailing truck to a locomotive with two driving axles. "Nothing can be said in favor of the Columbia or Atlantic type," he declared, adding later "Nothing has been accomplished by the Columbia or Atlantic types of engines that can not be more satisfactorily accomplished by the 8-wheel American and 10-wheel types." (Forced to choose between the two, Prince plumps for the 2-4-2 Columbia, further cementing his hold on the adverse trend of history in the face of the consensus that the arrangement rode badly.)

Prince backed up his claims with deeds, building several classes of Camelback 4-4-0s. But the Reading also built several dozen Atlantics, which became known as premium Flyers.

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Class 121/C-5a (Locobase 9762)

Data from Angus Sinclair, Railway and Locomotive Engineering, May 1902, p. 202

This class of James Milholland's 1874 Eight-wheelers were also known as "swallow tails" because the firebox sloped from 46" in the front of the cab to 32" at the fire door with the grate sloping down toward the front. He comments: "This was done to reduce the weight overhanging the back drivers and it gave a very roomy cab." The cab was more of a turret and had a hexagonal plan.

Sinclair also noted that as of 1902, 139 was hauling 3-4 cars on the Allentown-Philadelphia run of 136 miles round-trip and consuming 4 tons coal (59 lb/train mile).

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Class 356/D-2c (Locobase 9639)

Data from J Snowden Bell, "Improvement of Locomotive Boiler Construction," Nineteenth Annual Convention of the American Railway Master Mechanics' Association, June 15, 16, and 18, 1886 (Cincinnati: Aldine Printing Works, 1886), especially pp.63- T. Everett Austin, "Fast Passenger Locomotives," Proceedings of the Engineers' Club of Philadelphia (Vol. V, No. 2, August 1885), pp 97-99.

Notable in this early-Wootten-era camelback were the large number of tubes with a small diameter. (A variant with fewer larger-diameter tubes is shown in Locobase 6796.) Its firebox heating surface was augmented by 32 sq ft (2.95 sq m) in the combustion chamber.

Bell's 1886 presentation illustrated the appeal of the large grate with the soft draft in describing one set of tests:"Experiments with lignite, containing 20 per cent. of water, made with a consolidation engine in coal train service, developed an evaporative efficiency of 3.43 pounds of water per pound of fuel, and a percentage of total heat utilized of 42.1."

Obviously, these aren't brilliant numbers when compared with the usual ratios using regular soft coal. But they were generated by "free fuel". Moreover, said the author, "On one trip of 58 miles, observed by the writer, the engine steamed with perfect freedom throughout the run, and this fuel appeared to involve no difficulty whatever in firing."

He noted a performance by the 372 after it appeared at the May-June 1883 National Exposition of Railway Appliances. The Burlington Road tested the engine burning all kinds of fuel: anthracite waste, egg anthracite, and bituminous slack. On 19 June 1883, the 372 ran the 37 miles (59.6 km) between Chicago and Aurora using "Streator's dirt or screenings" to pull a train of 45 empty stock cars and a single passenger coach. The author noted that the engine steamed "steaming with such freedom that the fire doors were open much of the time to prevent too frequent blowing off, no black smoke being emitted and but few cinders, although the slack was very fine, many particles being less than one grain in weight."

Apparently persuasive for the Burlington were the post-test calculations. "The actual weight of fuel used was 6,575 pounds, which evaporated 47,643.5 pounds of water, or 7.15 pounds per pound of fuel. It was stated by those having large experience with Western coals, that no engine having an ordinary fire-box could make steam from the refuse used on this trip."

The four lower-numbered locomotives were not updated, but the four later ones were rebuilt as D-4b or D-4c locomotives

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Class 411/D-5c, D-5d (Locobase 3078)

Data from Report of the Proceedings of the 14th Annual Convention of the American Railway Master Mechanics Association - June 14-16, 1881 (Cincinnati: Wilstach, Baldwin & Co, 1881) p. 74. See also "Fast Express Locomotive for the Philadelphia & Reading", Railroad Gazette, Volume 13, No. 1 (7 January 1881), pp. 6-7, and No 2 (14 January 1881), p. 20; and "Wootten's Fast Express Locomotive" editorial, also page 20.

The report on these early Wootten-boilered engines claimed they would be the largest passenger engines in service at that time. In the May 1881 Journal of the Franklin Institute, J S Bell noted that the height of the firebox was only 2 ft 5 in above the grate. Baldwin produced fourteen more (Locobase 10818).

Over the 59.2 miles between Philadelphia and Bound Brook, NJ, 506 pulled a 15-car, 360-ton train with almost 900 passengers up a ruling grade of just over 1% at an average of 42 mph (68 kph). In that run, the engine burned 62 lb (17.46 kg/km) of fuel per mile, described as the "equivalent to 34 1/2 lb per square foot per hour. " 411 managed 10 cars in 70 minutes over the same route (50 mph), even though it contended with slow orders on two miles of bridging.

"When doing full work," said the RG report, "...the engine consumes 53 lb (24.04 kg) of anthracite coal per minute and evaporates 55 gallons (208 litres) of water in the same time." This was considered economical running as the "greatly enlarged grate area" offered "exceptionally free passage for air through the bed of fuel, which is maintained at a depth of from four to six inches [102 to 152 mm]." A reservoir in the cab supplied oil to "all bearings which are likely to need lubrication during the trip." Overheating axle bearings were cooled by a system of flexible tubes connected to the water tank.

For much greater detail on the Wootten concept, see the editorial on page 20 cited above, which was, overall, positive.

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Class 569/D-5c (Locobase 10818)

Data from RDG 11-1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also DeGolyer, Volume 15, p. 63. Works numbers were 10898, 10901-10902, 10908, 10918 in May 1890; 10938-10940, 10948-10949, 10955-10956, 10969, 10971 in June. Five were delivered to the Philadelphia & Sea Shore, but they were repossessed and turned over to the Reading in 1892. See Locobase 3078 for the two home-built sisters.

14013, 14016 in May 1894 went to the South Jersey, but were taken over by the Reading in 1898.

Locobase isn't sure, but it seems as if some of these locomotives were superheated later on, retaining 205 of their small tubes and adding some superheater flues. Others were rebuilt with 20" x 22" cylinders and consequently generated lower tractive effort. These may have been designated D9-e.

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Class D-1 / D3-i (Locobase 6796)

Data from DeGolyer, Vol 11, p. 198 and Rdg 11 - 1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Baldwin works numbers were 6789 in April 1883; 6745, 6752, 6758, 6766, 6773, 6781, 6784 in May; 6786, 6799, 6805, 6814, 6822 in June; 6843. 6848 in July.

This order represents one of the first large batches of locomotives built with Wootten fireboxes. The later Reading diagram shows 188 tubes for a total of 1,052 sq ft (97.75 sq m).

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Class D-3h (Locobase 3077)

Data from Rdg 11 - 1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

As was the case on many railroads in the anthracite-coal region of Pennsylvania, this Eight-wheeler was a camelback. The arrangement allowed the line to burn the culm resulting from anthracite mining as fuel.

The relatively small drivers indicate a mixed-traffic role for this sub-class, which was created out of earlier D-2a, b, and c engines delivered on 68 1/2" drivers in 1881-1882.

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Class D-4f, g (Locobase 4789)

The date is the date of publication of an article in Scientific American on the Royal Blue express service. This design appears to be a slight enlargement and improvement on the 1883 design. It has taller drivers and slightly higher boiler pressure.

Looking at the roster laid out in the Railway & Locomotive Historical Society Bulletin #67 pp. 85-86, Locobase argues for the D-4 subseries locomotives shown in this entry.

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Class D10-a (Locobase 10827)

Data from RDG 11-1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See als S F Prince, Jr, "Rebuilding Locomotives - Philadelphia & Reading", Railroad Gazette, Volume XXXVII, No 2 (24 June 1904), pp. 46-48.

Prince tells us this is 317 rebuilt from its original 4-2-2 compound layout (road #378, Locobase 12184) after "...it was found to be practically impossible to find a service for which this type of engine was adapted. It have a suitable train one way over the road, but on the return trip the load or number of stops would almost invariably render schedule time an impossibility."

To put more adhesive weight on the rails, the layout was changed to an Eight-wheeler while retaining the tall drivers. (Photos show that the original layout placed the firebox doors and cab high enough that no major changes had to be made when adding the second driving axle.) Also the 11" piston valves were replaced by Richardson balanced slide valves. Overall engine weight increased by less than 20,000 lb while adhesion weight rose by 47,600 lb.

Later fitted with 309 1 3/4" tubes which raised heating surface slightly to 1,768 sq ft.

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Class D10-b (Locobase 10826)

Data from RDG 11-1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

This class was made up of two rebuilt engines that served as testbeds for the fast Vauclain-compound locomotives fitted with very tall drivers. 378 was rebuilt as 317 and is described in Locobase 10827. 316 originally came into service as #385, the 4-2-2 Bicycle described in Locobase 2563.

Later fitted with 309 1 3/4" tubes which raised heating surface slightly to 1,768 sq ft.

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Class D11s (Locobase 3080)

Data from "Philadelphia & Reading 4-4-0 Type Locomotive," Railway Age Gazette, Volume 56, No 16 (17 April 1914), pp. 872-875; "American Type Locomotives for the Philadelphia & Reading", Railway Review,Volume 54, No 5 (May 1914), pp. 678-680; and DeGolyer, Volume 49, p. 309. See also Reading 11 - 1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. (Chris Hohl's 1 October 2019 email notes the correct tender coal capacity of 10 1/2 tons.) Works numbers were 41191-41195 in February 1914, 41213-41217 in March.

These American-arrangement engines were among the last 4-4-0s to be built for a Class 1 railroad. RAG explained that the anthracite-coal-burning Woooten firebox didn't need to be long, just wide, and it could be carried over the second set of drivers. Also, the Reading didn't need the speed over most of its lines that had led it to adopt high-drivered Atlantics on the Atlantic City run. So the cab could be positioned in its traditional spot behind this very wide firebox instead of on the boiler.

"The result," said the journal, " is a locomotive which is well adapted to heavy local or express traffic on divisions having moderate grades and where train loads are within the capacity of an engine of this type." Both small and large tubes were narrower than their counterparts on most other railroads. Firebox heating surface included 42 sq ft (3.9 sq m) of combustion chamber, which was separated from the rest of the firebox by a half wall.

They were also fitted with Ragonnet power reverse as a result of an Extra Work Department order #704 dated 22 January 1914. The cylinders received their steam through 11" (279 mm) piston valves. The front drivers were counterbalanced to 35% of the weight of reciprocating parts, the rear set to 31%.

A follow-up note written 30 March 1915 said that "J A Trainer reported failure of valve motion bearer", including the usual admonition "make stronger hereafter." Other "hereafter" comments included recommending a one-sheet casting for the power reverse shaft bearing mounted on the throat sheet and finishing the face of the drivers' counterbalances. "The RR Co", said this latter note, "was not satisfied with the finish [of this ten-engine set]."

The 1926 Reading diagram shows that boilers in at least two of the class were modified with different tube counts. One saw a reduction in 1 3/4" diameter tubes to 198, which yielded a total evaporative heating surface area of 1,480 sq ft (137.5 sq m). Another received a substantially changed arrangement in which 198 small-diameter tubes were replaced by 129 2" tubes. So its internal makeup included three tube diameters that offered 1,648 sq ft (153.1 sq m) of evaporative heating surface area.

All but two of the class were scrapped just before the US entry into World War II. The last two continued to work throughout the rest of the war before being scrapped in June 1946.

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Class D4-h (Locobase 10819)

Data from RDG 11-1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

This engine was rebuilt on the frame of #174, a Reading engine originally built in April 1883. It had a smaller grate than most of the other camelback Eight-wheelers on the Reading and used fewer tubes of larger diameter.

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Class D5-b (Locobase 11612)

Data from Baldwin Locomotive Works Specification for Engines, 1888, as digitized by the DeGolyer Library of Southern Methodist University Vol 15, p. 63

Works numbers were 9986-9987, 9997, 10001 in May 1889; 10031-10032 in June. For some reason, road number 1018 was assigned to works 10031 and 1019 adorned 10001.

Firebox heating surface included 39.02 sq ft of combustion chamber.

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Class D5-f (Locobase 3079)

Data from RDG 11-1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also DeGolyer, Volume 23, p. 285 and Volume 24, p. 273; and Railroad & Locomotive History Society Bulletin #67, p. 72. Works numbers (260-280) were 18894-18895, 18902-18905, 18921-18924 in April 1901; 20580-20581, 20588-20590 in June 1902; 20686-20687 in July.

Baldwin's specs for the first ten locomotives didn't include weight estimates. 270-279's adhesion-weight estimate was 87,600 lb (39,735 kg) and engine weight at 132,600 lb (60,146 kg) Weight of the original tender was estimated at 120,000 lb (54,431 kg); water capacity was 5,950 US gallons (22,521 litres).

D5-h (280-294) were virtually identical except for slightly higher weights of 99,480 lb adhesion and 144,100 lb total engine weight and changes in the boiler, according to the 1933 Equipment List. Their works numbers were 27674-27675, 27691-27692, 27702, 27718, 27730, 27741-27742, 27750, 27827, 27828 in March 1906; 27839-27841 in April.

Most noticeable about this camelback design was its almost-square bore/stroke ratio. The Bulletin described these as "rugged, compact machines used in heavy suburban and short express runs."

Most were scrapped in the 1930s after 30-35 years of operating life.

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Class D5-g (Locobase 10820)

Data from RDG 11-1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

This quartet was rebuilt from an earlier class that had come from the Reading's own shops in 1884-1885.

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Class D5-h (Locobase 16268)

Data from RDG 11-1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also DeGolyer, Volume 25, p. 220 and Railroad & Locomotive History Society Bulletin #67, p. 72. Their works numbers were 27674-27675, 27691-27692, 27702, 27718, 27730, 27741-27742, 27750, 27827, 27828 in March 1906; 27839-27841 in April.

Locobase 3079 shows the first 20 camelback Eight-wheelers built 1901-1902 with the same boiler and driver diameter. These D5-h were virtually identical except for slightly higher weights and slightly more firebox heating surface area. Baldwin's adhesion (91,000 lb/41,277 kg) and engine weight (135,000 lb/61,235 kg) estimates came out lower than the weights shown in the 1926 diagram book.

The R&LHS Bulletin described these together with the D5-f as "rugged, compact machines used in heavy suburban and short express runs." Like the D5-f, the D5-h were scrapped in the 1930s after 30-35 years of operating life.

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Class D8-a (Locobase 10821)

Data from RDG 11-1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

This later design of anthracite culm burner used the same firebox as the D5 series, but attached a longer boiler with larger-diameter tubes. The seventh in the class replaced an earlier K1-a with the same road number.

A few later gave up fourteen boiler tubes, which reduced total evaporative heating surface to 1,545 sq ft (143.6 sq m).

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Class D8-b (Locobase 10822)

Data from RDG 11-1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

Using the same boiler and grate as the D8-a (Locobase 10821), this batch adopted slightly larger cylinders (which added 2" to the bogie and shifted the fulcrum forward 7"), noticeably taller drivers, and a 25% increase in boiler pressure. The tender also added quite a bit of weight.

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Class D8-c (Locobase 10823)

Data from RDG 11-1926 Locomotive Diagrams and RDG 9 - 1933 EQP LIST supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. All were manufactured in April 1911.

This class reverted to the smaller drivers used by most Reading passenger camelbacks,b ut increased its boiler size by almost 25% over the D8-b (Locobase 10822). According to the 1933 Equipment List, this was a "heavier and later type of D8-b".)

T401, 404, 406-408 were superheated in 1920 (4) and 1922 (401) and redesignated D-8sd. Two of remaining five were scrapped in 1932 (402-403), one in 1934 (409), and one in 1940 (400).

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Class D8-sd (Locobase 10825)

Data from RDG 11-1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange.

At least 5 of the D8-c camelbacks were later superheated with a modest kit that contributed to a good increase in efficiency. At the same time, the Reading changed the valve gear to outside Walschaert radial valve gear.

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Class Gowan & Marx (Locobase 1029)

John H White, Jr, A History of the American Locomotive: Its Development: 1830-1880 (New York: Dover Publications, 1979 - original publication in 1968) describes differences in cylinder measurements; those given were recollected by designer Joseph Harrison in 1872. See also G N Nichols, "Statement of the Performance of the Locomotive Engine 'Gowan and Marx'...with a train of 100 loaded cars- February 20th, 1840" date 24 February 1840 in Railway locomotives and cars, Volume 11, (Jul-Dec 1840), pp.296-298.

Note: G N Nichols served as Superintendant [sic] Transportation, Philadelphia & Rading Railroad. Nichols's account of the 101-car train's performance gave the cylinder stroke as 16" (406 mm) and the coupled wheel diameter as 42" (1,067 mm). During the run, boiler pressure ranged from 80 to 130 psi, "to which pressure the safety valve was screwed down."

One of the first engines to have equalizing levers on the running gear. As White demonstrated, there were many ways to equalize the movement of the two axles. That adopted for the Gowan & Marx would appear on thousands of engines and represents perhaps the single greatest American contribution to steam locomotive design (other than sheer size).

Each axle box was free to move within a limited vertical range. The two boxes on each side of the engine were joined by a lever that pivoted around a stand located between them. The stand's vertical movement was buffered by an inverted leaf spring whose ends were secured very near the horns in which the axle boxes rode. As the engine encountered irregularities in the track (a constant occurrence), the movement of each axle box up or down was compensated for by an answering movement in the other box on the same side. Thus, both axle boxes operated as a unit. When combined with the center-pivoting leading bogie, the suspension resembled a three-legged stool.

The Gowan & Marx ran for more than 20 years, amassing 144,000 miles in revenue servicre. In one demonstration in February 1840, the engine pulled 104 cars weighing a total of 423 tons (note how small the freight cars of the time were). Most of the time the G & M burned wood until 1855, when she was converted to burning coal.

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Class Hiawatha (Locobase 13425)

Data from "Economy of Anthracite Coal for Locomotives," The Scientific American, Volume 2 (1860), p. 197; and "American Anthracite Coal Burning Locomotive", Engineer, Volume 11, No 6 (8 February 1861), p. 90. . See also Paul T Warner, "The Development of the Anthracite-Burning Locomotive," Railroad & Locomotive Historical Society, Volume 52, pp. 11-28.

James Milholland was the first locomotive designer on a major railroad to put dozens of anthracite-burning locomotives in service. Warner comments that Milholland raised the firebox above the driving axles to gain the grate size needed to burn the thin bed of anthracite properly. The grate had twelve water-tube grate bars. A cutaway illustration shows the unusual layout that included a turreted cab whose firebox extended nearly to the tender, two steam domes at opposite ends of the boiler, and inverted-cone spark-arresting stack.

Milholland's 1859 report claimed that the new engines Hiawatha and Minehaha had delivered on his promise:"In economy of fuel and repairs, and general efficiency, these locomotives have proved superior to any yet used, and are believed to furnish an excellent model for others which may be hereafter required for similar service."

The Scientific American report details some of these engines' performances. The Hiawatha could take six passenger cars (a trailing load of 72 tons) the 93 miles from Pottsville to Philadelphia in a little over 3 hours while consuming 2,350 pounds of coal (i.e. 25 lb/mile). As the fall from Pottsville to Philadelphia totalled 559 feet, the Hiawatha's return-trip consumption of 2,650 pounds of coal was at least as impressive.

Warner adds that a long series that would be built "with comparatively little variation ... until the advent of the Wootten boiler in 1877."

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Class K52/K1-a (Locobase 11669)

Data from Baldwin Locomotive Works Specification for Engines, as digitized by the DeGolyer Library of Southern Methodist University Vol 14, p.82. Works numbers were 9250-9252, 9254-9255, 9258 in May 1888..

This was an unusual sextet for the Reading in this period - conventional-cab, narrow-firebox Eight-wheelers. This class was renumbered in 1900 in a broken series.

242 was the first to leave service, being replaced by a D8-a in 1922. The others were all replaced in the mid-1930s.

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Class K56 / K1-c (Locobase 14633)

Data from "New Locomotives of the Philadelphia & Reading Railroad," National Car and Locomotive Builder (April 1888), p. 59. See also Locomotive Engineers' Monthly Journal, Volume 22, No 2 (February 1888), p. 127 and DeGolyer, Volume 14, p. 121. Works numbers were 9166-9168, 9173, 9177, 9191, 9323 in June 1888.

These Eight-wheelers were designed by the Reading's George W Cushing to replace engines produced earlier by John Wootten. The firebox was wider than most of the narrow fireboxes then in use and the boiler was considered quite large in relation to the cylinders it supplied. But the boiler specs changed twice for this class and a contemporaneous note in the LEMJ--published by the Brotherhood of Locomotive Engineers--provides a clue as to why.

"It has finally been decided that the Wootten dirt-burning engines on the Philadelphia & Reading Railroad, whose poor performances have long been commented upon, must go," proclaimed the journal with obvious satisfaction. "They have been the most expensive feature of the road's equipment, and the present management has determined to substitute standard boilers for the Wootten fire-boxes as soon as the latter are worn out. Several of the engines have already been changed at the Reading shops and the others will be altered as rapidly as possible." [LEMJ credits the announcement to Iron Age.]

Cushing's answer was to raise the firebox above the driving axles to allow for a wider grate. The original specs recorded on 8 September 1887 called for 287 tubes #12 Birmingham Wire Gauge (BWG) thickness [0.109" walls] in a wagon top boiler. After the class's introduction in early 1888, however, all seven locomotives were given a new straight boiler with 262 tubes (25 fewer) made with thinner walls [0.095"]. Locobase offers a guess that the original tube spacing was simply too dense to permit the desired water circulation.

The BLE's hopes that the Wootten "dirt-burner" boiler had been discarded were soon dashed. The Reading produced a few more conventional cab locomotives (see, e.g. Locobase 14635), but the camelback would return. And in 1898, the Reading redefined the