Philadelphia & Reading 2-8-0 "Consolidation" Locomotives in the USA

Class 175/I5-a (Locobase 9424)

Data from English Mechanic and the World of Science (#1258 - May 3, 1889), p 193. See also John K Brown, The Baldwin Locomotive Works, 1831-1915: A Study in American Industrial Practice (Baltimore: Johns Hopkins University Press, 1995), pp. 78-80 and DeGolyer, Volume 14, p. 143. Works numbers were 9294-9295, 9307, 9309 in June 1888 and 9351-9352 in July.

The anonymous author of the English Mechanic report gives no more than the specification and a brief report that these "heavy locomotives have been put to work in the mountain division ..." and that they were intended to burn anthracite coal. When delivered, the class's safety valve was set at 140 psi.

A photograph shows that these were big-barrelled and conventionally laid out Consolidations - their power dimensions and layout were unusual on the camelback-rich Reading. For their time - the mid-to-late 1880s, these were among the biggest 2-8-0s in service.

Brown cites this George W Cushing design as an example of Baldwin's willingness to build to suit any customer's particular whim and to exploit the lessons learned if the design was a success. In this case, the Reading engines served as the baseline for a Northern Pacific class that was ordered soon after these were produced. See Locobase 829.

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Class 183 / I5-c (Locobase 12009)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 17, p. 167. Works numbers were 12354, 12359, 12364-12366, 12368-12369, 12373-12374 in December 1891; 12725 in June 1892.

This set of Vauclain compound Consolidations added some size to the boilers then used by the Reading for such engines. They were the first batch of many such four-cylinder compounds, most of which used the then standard 14" HP and 24" LP cylinders supplied by 10 1/2" piston valves.

After little more than a decade, they were converted to simple-expansion engines with 22" x 26" cylinders; see Locobase 10846.

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Class 365/I-4b (Locobase 12200)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Vol 20, p. 137. Works numbers were 15039-15043 in September 1896.

This quintet of Vauclain-compound Consolidation was identical to the large class that had been entering service since 1892 (see Locobase 12058); they even had the same 10 1/2" piston valves. One significant difference lay in the use of drivers standing 5" taller.

All were renumbered in 1900. It appears that 935 (ex-467) may never have been converted to simple-expansion and was scrapped as a compound in March 1935. The other 4 were rebuilt as simple-expansion locomotives in 1902-1905 and eventually topped off the I-4d class (see Locobase 10845).

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Class 910 / I50 / I2-a (Locobase 11662)

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

1887

December 8977-8978

1888

January 8988-8989, 9003-9004, 9008, 9010, 9031-9032; February 9047-9048, 9070-9071, 9076, 9085, 9087; March 9098-9099, 9105, 9113, 9118, 9131, 9135; July 9379, 9382, 9385; August 9386, 9420-9426, 9429-9430, 9439, 9444, 9446; September 9464.

Most of this class of camelback Consolidations was scrapped in the 'teens, but a few lasted into the twenties and 852 wasn't scrapped until February 1930.

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Class I1-a (Locobase 8529)

Data from Emory Edwards, Modern American Locomotive Engines: Their Design, Construction and Management. A Practical Work (New York: S. Low, Marston, Searle

& Rivington, 1883), p 119 and "Consolidation Locomotive for the Philadelphia & Reading," Scientific American Supplement, No. 252, pp. 4012-4013. See also DeGolyer, Volume 10, p. 198; and Report of the President and Managers of the Philadelphia & Reading Railroad Co to the Stockholders - January 1882, for the Year Ending November 30, 1881(Philadelphia: Allen, Lane & Scott, 1882), pp. 71-73.

Works numbers were 4921, 4932, 4935-4937, 4939 in January 1880; 4949, 4952, 4954, 4958, 4962, 4965 in February; 5001, 5013, 5019 in March; 5035-5036, 5047, 5050, 5065 in April; and 5075 in May.

Note that this Wootten-patent firebox had the long combustion chamber that was usually installed in such boilers early on. It added 57 sq ft (5.3 sq m) to the heating surface area. It also had a Wootten-patent feed water heater that received its water through an injector rather than a pump.

It's worth underscoring the radically different shape of this firebox compared to the orthordox deep furnaces found in most North American locomotives. The standard deep firebox was between 33 and 34 3/8" (838-873 mm) wide and anywhere between 65 and 80" deep (1,650-2.032 mm). The Wootten firebox spanned 96 1/8" (2,442 mm) and was a shallow 45" (1,143 mm) deep.

A Consolidation of this design was used to test lignite fuel for possible applications in western railroads. A Coal Trade Journal report outlined the runs and results:

"A train of 100 coal cars was hauled up a 30-foot grade at the rate of 60 miles per hour, or one mile a minute. This peculiar coal required a peculiarly constructed engine grate, as it burns almost entirely to ashes, leaving some clinkers. The grate of the engine is divided into four movable sections, so that one portion of it can be cleaned without disturbing the fire over the other portions. In this way a steady fire with plenty of draft can be maintained. The fire-box has two doors, and the engine requires the services of two firemen, whose apartments are entirely separated from those of the engineer."

These trials led to the Northern Pacific order in early 1881 of eight Moguls and two Eight-wheelers (Locobases 808 and 873).

Not quite two years after this large class entered service, Reading's President Frank S Bond summarized in January 1882 the purported advantages of the design, but followed that with a strong caution:

"What is known as the "Wootten Boiler," is an invention or device of Mr. John E. Wootten, General Manager of the Philadelphia and Reading Railroad. Mr. Wootten is a thoroughly capable, practical mechanic, who was for many years in charge of the shops and machinery of the company, and since January, 1877, has been its General Manager. This boiler was perfected in the company's shops, and has been put into practical operation on the company's road under Mr. Wootten's immediate supervision. The principal difference between it and ordinary boilers is the increased grate surface, the Wootten boiler having about treble that of ordinary locomotive boilers burning anthracite coal. It is claimed that waste coal from the dirt heap at the mines can be economically used in such boilers for fuel, and that in using any ordinary fuel there is a saving, equal to 15 per cent., and a saving equal to 75 per cent. when buckwheat coal or waste from the dirt heap is used."

The phrase "thoroughly capable, practical mechanic" puts Wootten in his place, but the report's description can't be faulted. ( In Appendix A, the Reading's Mechanical Engineer Frederick Sickels adds some nuance to the account: ". It was obvious that at low speed the increased grate surface of the Wootten boiler afforded facilities for burning a poorer quality of coal than could be successfully consumed in ordinary locomotive boilers. The saving resulting from being able to burn the refuse coal, of which enormous deposits exist throughout the mining regions, makes the so-called Wootten engine better adapted for the requirements of the Philadelphia and Reading Railroad Company's freight service than the ordinary coal-burning locomotive ..." )

Sickels noted, however, that passenger engines did not burn "fine coal" and probably did not need the extra expense and odd configuration of the Wootten boiler.

Bond then offers his first caveat:

"By reason of its peculiar construction, when the Wootten boiler is once adopted, the engines can not afterwards be changed, and the old standard restored, except at very considerable cost. The General Manager reports that there are now one hundred and four locomotive engines on the Reading Road with these boilers, that have cost the company $1,100,000. The Receivers have purchased thirty, during the past year, and as many more are under contract for future delivery."

Locobase's paraphrase: "We've invested over $1 million in dozens of locomotives that cannot be easily modified."

The report pulls back even further from an endorsement of this trend:

"The record of the "Wootten boilers" used on locomotive engines, under supervision of the inventor, apparently shows considerable saving in cost of fuel. The improvement has not, however, been adopted upon any other road, although the attention of the mechanical departments of other companies has been called to it. It has been tried by the Baltimore and Ohio, the Wabash, the Lehigh Valley, the Delaware, Lackawanna and Western, the Lehigh Navigation Company Railroad, and the Camden and Atlantic Railway companies, but it has not given such satisfaction to any of these companies, as to lead to its adoption."

Paraphrase: "Sure, it seems to work, but we turned around to see what other railroads were following us and didn't see any." Locobase notes that the Lehigh Valley, the DL&W, Lehigh & Hudson, and the Camden & Atlantic would adopt Wootten boilers with a few years.

Then the authors offer a reproof and an order to halt for now:

"On such a record, its general adoption, at such a heavy cash outlay, by the Philadelphia and Reading Company, is, not improperly, subject to criticism, even though they should hereafter prove to be all that is claimed for them. It is certainly unusual, and of doubtful expediency, to make such a radical change in the standard of locomotive equipment, on such limited ex parte evidence as to the value of an improvement. It would seem now to be but prudent, before further expenditure shall be made in that direction, for the Philadelphia and Reading Railroad Company to arrange to have these engines thoroughly tested on other roads, under an absolutely disinterested supervision, the records for comparison with the consolidation or other standard locomotives, to show original cost of engine and cost of repairs, the hauling capacity and cost of firing, and the cost of fuel, including the cleaning, handling, and reshipping of waste fuel used. Mr. Wootten is desirous of having such an impartial trial and examination made as to the value of his invention."

One early trial matched a camelback Consolidation against the "ordinary" 2-8-0 then in service with the Reading. The ordinary engine consumed 97 1/2 lb (44.2 kg) of coal per mile run, evaporating 6.61 lb (3.0 kg) of water per pound of coal. The camelback's boiler burned 73 lb (33.1 kg) of coal per mile and evaporated 8.93 lb (4.05 kg). Another way to consider the comparison is note that the two boilers evaporated the same amount of water (643 lb vs 651 lb) per mile, but the camelback required 25% less coal. The softer draft over the big broad grate reduced sparks and cinders as well.

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Class I1-b/I1-c (Locobase 11784)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 10a, p. 198. Works numbers were

1881

March 5536, 5539, 5544, 5552, 5564; April 5570, 5581, 5589, 5609; May 5615, 5625, 5628, 5632, 5639, 5647, 5651; June 5658, 5669, 5678, 5680, 5699, 5700; July 5710-5711, 5716, 5723, 5726, 5732, 5738, 5744.

1882

April 6154, 6156, 6164, 6166; May 6200-6201, 6213-6214, 6221-6222; June 6237, 6241-6243, 6255, 6259; July 6274, 6278, 6295, 6299, 6302, 6306, 6309-6310; August 6329, 6332, 6340-6341, 6352, 6356

1883

July 6833-6834, 6849, 6854, 6859, 6865, 6870; August 6872, 6877, 6881; October 6974, 6976,

6993, 6999; November 7027, 7032; December 7076, 7078

1884

January 7109, 7113, 7141-7145; February 7163, 7174, 7182-7183, 7185, 7188, 7194; March 7197, 7207, 7214, 7217-7218, 7227, 7232; 7240; April 7246, 7250, 7253, 7269, 7271, 7284; May 7287, 7292

Similar to the immediately preceding I1-a (see Locobase 8529), this large class of camelback Consolidations had shorter boilers and consequently smaller heating surfaces. However, a significant portion of that area was directly heated as the combustion chamber contributed 57 sq ft to the total.

Most of this class was scrapped at the end of the first decade of the 20th Century. A few were converted to I-1e or I-1a and retained for another 15 to 25 years.

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Class I1-d (Locobase 10840)

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

This class consisted of rebuilt Baldwin engines that were originally delivered in 1880. Some were later retrofitted with fewer tubes for a total evaporative heating surface of 1,239 sq ft.

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Class I1-e (Locobase 10841)

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

These were rebuilt from a class supplied by Baldwin in 1881. Some were later retrofitted with 161 tubes for a total evaporative heating surface of 1,079 sq ft (100.24 sq m). .

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Class I10-sa (Locobase 414)

Data from DeGolyer, Vol 74, pp. 144. Works numbers were 57348-57356 in October 1923; 57507-57516 in November; 57577-57581in December; 57596 in January 1924; 58217-58219 in February 1925; 58258-58263, 58275-58280, 58325-58330 in March; 58371-58383 in May.

Linn Wescott (Model Railroader Cyclopedia - Vol 1, 1960) says that this design was similar to that of the Western Maryland (Locobase 411), but that the Wootten firebox lengthened them by a foot. In addition, the firebox's combustion chamber added 91 sq ft (8.45 sq m) to the engine's direct heating surface area.

They were good drag freight engines with a high axle loading. A typical train consisted of 100 loaded coal cars over a ruling grade of 0.3%. Wescott adds that "Like most Consolidations, they were short on steam for any long steady grade pulling." These engines had 13" (331 mm) piston valves vs the 14" (356 mm) valves fitted to the Western Maryland locomotives.

Stretching the boiler by a foot and dropping it on a new set of running gear created a home-built Northern. 30 T-1s were assembled this way from the last 30 I10-sas (2020-2049) to be delivered.

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Class I2-c (Locobase 11628)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 16, p. 3. Works numbers were 10816-10817, 10820-10824, 10829 in April 1890 and 10899 in May 1890.

One of several I2 cameback Consolidation subclasses, this set of ten was the last new-builds. 879 (ex 582) underwent a rebuild in February 1907 and emerged as an I2-f.; see Locobase 10842 Three others were scrapped in 1915, 1917, and 1918; the other six scrapped in 1923-1929.

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Class I2-c/e/f (Locobase 10842)

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

As part of the shops' conversion of the Reading's 1890 vintage drag-freight camelback Consslidations delivered as Vauclain compounds (Locobase11628) to simple expansion, they fitted cylinders with 1/2" (12.7 mm) larger diameters. This increased slightly the class's starting tractive effort on these

In addition to the comounds, at least 54 I-1 Consolidations went through the program between 1906 and 1910.. Most entered serviice as I-1b with I-1bs accounting for most of the rest. Nine I-1as filled out the converson roster. Two different "standard square back" tenders" carried the coal and water; coal capacity remained the same, but the larger tender carried 6,000 US gallons (22,710 litres) of water.

Some were later retrofitted with 189 tubes for a total evaporative heating surface of 1,401 sq ft (130.16 sq m). Evan as late as the 1926 diagram book, their Wootten boilers still included a relatively long combustion chamber. According to the 1933 Equipment List, the I2-f was the I2-e design "...with the wheel base moved back.". According to the diagram, this resulted in an engine wheelbase of 22 ft 4 1/2 inches (6.81 metres).

After its 1909 refit as an I2-f, the 735 remained on the P&R roster until 1925, when it was sold to the Williamsport & North Branch railroad as their 23. That short line operated the 23 until it went to the ferro-knacker in 1934. Having scrapped the 23, the W&NB acquired the 815 in 1934, renumbered it 25, and ran it for two years before sending it to the scrapper.

The rest of the I2s remained with the Reading, which began disposing of the class in 1923 and finishing with the 804 in October 1940.

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Class I3-a (Locobase 10843)

Data from RDG 11 -1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Road numbers continued 739, 741. 745, 751, 757-758, 760-761. 764-766, 768-769, 781,803, 814, 788-789, 803, 814 818, and 823.

The I-3a class consisted of I-1 class (Locobases 8529 and 12784) camelback Consolidations that were converted to 2-8-0 switchers. Reading's diagram seems to be a composite of I-2 and I-6 data and shows a converntional firebox layout.

Four different "P&R old-style" tenders appear in the 1926 diagram, as shown in the table

# in 1926 Water (US gal) Coal (short tons) Light (lb) Loaded (lb)

7 4,000 7 37,000 84,000

10 5,000 10 40,000 101,600

10 6,000 10 51,000 108,000

11 7,000 11 52,000 116,000

Some were later retrofitted with 189 tubes for a total evaporative heating surface of 1,401 sq ft (130.36 sq m). By 1926, only 14 out of the 37 remained in service and these had been withdrawn by 1933.

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Class I3-a (Locobase 10844)

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

These were delivered by Baldwin in 1882 and were later classified as I-1bs. After the turn of the century, the Reading rebuilt one in each of the four years from 1902-1905 to a single-cab design and dubbed that configuration class I-3a.

Some boilers were later reconstructed with 206 2" tubes for a total heating surface of 1,708.4 sq ft.

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Class I4-a, I4-b (Locobase 12058)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University, Volume 17, p. 167. Works numbers were 12999-13000, 13007-13008 in October 1892; 13012. 13019, 13023, 13028-13029, 13032 in November; 13069-13070, 13088, 13098, 13107, 13125-13127 in December; 13143-13144, 13161-13162, 13178, 13184-13185, 13192 in January 1893; 13199-13200, 13202-13204, 13229-13230, 13234, 13243 in February; 13301-13302, 13307, 13312, 13317, 13329-13330 in March; 13342, 13345-13346 in April

With each successive batch, it seems, the Reading's camelbacks grew a little more in boiler capacity, This big class of Vauclain compounds added to an already large stud of Mother Hubbards ranging all over the railroad.

Starting in 1903, the entire class was rebuilt to I4-d simple-expansion standards. Locobase presumes that as they were then class I4-d, they were similar or identical to the locomotives described in Locobase 10845.

In the late teens, early-20s, 19 of these surrendered their trucks and became class E4-a 0-8-0 switchers. Most of these lasted into the 1940s.

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Class I4-d (Locobase 10845)

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

Two large classes of camelback Consolidations was delivered as Vauclain compounds with two 14" HP and two 24" LP cylinders and rolling 50 1/2" drivers; see Locobase 12058. Another smaller set was delivered with 55.6" drivers; see Locobase 12200.

They were rebuilt as simple-expansion engines in 1902-1905. Exactly half of the class gave up their leading trucks in 1916-1922 and as 0-8-0s, went into switcher duty as E3-b and E4-a numbered in the1400s.

Some were later retrofitted with 250 tubes for a total evaporative heating surface of 1,539 sq ft.

In 1933, 22 of the freighter I4-ds and most carried on for 40 years and more

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Class I5-a, -b, -c (Locobase 10846)

Data from RDG 11 - 1926 and Locomotive Diagrams and RDG 9 - 1933 EQP LIST supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Baldwin works numbers for the I5-b were 10808-10810, 10813, 10826-10827 in April 1890

The 1933 Equipment List says the I5-bs were the same as the I5-as except for the adoption of the alligator crosshead. I5-c engines were delivered as Vauclain compound system, then rebuilt as simple-expansion locomotives. Axle loadings on the I5-a (shown in specs) were 2,000-3,000 pounds higher as well.

Some were later retrofitted with 274 tubes for a total evaporative heating surface of 1,584.8 sq ft (147.25 sq m).

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Class I50/ 2" tubes / I2-a (Locobase 14635)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Volume 14, p. 194.

Works numbers were 9423-9424, 9430, 9439, 9444, 9446 in August 1888; 9464 in September.

As we noted in Locobase 14634, George W Cushing, new manager of motive power in 1888 for the Reading, wanted to compare Wootten's legion of camelbacks with a more orthodox layout. His first two locomotives with a standard, if relatively wide, firebox were the 933-934 (Locobase 14634), which had boilers of about the same size as the camelbacks, although the number of tubes was smaller and each tube larger in diameter.

His next set, shown in this entry, was based on the single engine 966 shown in Locobase 14633. The seven in this batch had deeper fireboxes and boilers with more tubes of the same 2" diameter as the the camelbacks.

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Class I50/ conventional (Locobase 14634)

Data from Baldwin Locomotive Works Specification for Engines as digitized by the DeGolyer Library of Southern Methodist University Vol 14, p.83. Works numbers were 9379 in July 1888, 9420 in August.

Apparently, George W Cushing, new manager of motive power for the Reading, wanted to compare Wootten's legion of camelbacks with a more orthodox layout. So two months after the Reading ordered the first 23 of the camelbacks shown in Locobase 11662, he directed the builder to complete two more with a 42" wide firebox.

Baldwin's spec sheet shows that the pair was identical to the others in the class except for the firebox.

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Class I6-a (Locobase 10847)

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

These were I7-f locomotives rebuilt by Baldwin with a wide-firebox boiler. 1101 was renumbered from 978, 1102 from 996, and 1103 from 1013 in April 1905.

1102 was scrapped in March 1935, 1101 followed in October. 1103 survived for another five years before being scrapped in October 1940.

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Class I6-b (Locobase 10848)

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

These were I7-g locomotives rebuilt by Baldwin with a wide-firebox boiler. 1108 was the former 1039, 1109 had been 1055, and 1110 entered service as 1058. They differed from the I6-as in having shorter boiler tubes.

1108 was scrapped in March 1935 with 1109 following in October. 1110 was dismantled in February 1937.

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Class I6-c, -d (Locobase 10849)

Data from RDG 11 -1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. See also DeGolyer, Volume 28, p. 240. Works numbers were 29875-29879 in December 1906; 29940-29941, 29962-29963, 29972, 30008-30009, 30030 in January 1907; 30064, 30155 in February.

A set of Baldwin camelback Consolidations that began with six rebuilt locomotives (I-6a and I-6b, shown in Locobases 10847-10848) and then supplemented by nineteen new-build locomotives beginning in late 1906. As delivered, the engines had a combustion chamber with a brick wall in the chamber.

All initially retained their 363 tubes and were designated I-6c, but the Reading rebuilt all of the class in 1921-1924. In the process, they deleted 39 boiler tubes. Most were scrapped in the 1930s with the last six--1112-1114, 1119, 1123,1124--going to the ferro-knacker in May 1941.

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Class I7-a, -b (Locobase 10852)

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

I7-a 16414-16423 in December 1898, 16500-16509 in February 1899

I7-b 17096-17101 in September 1899, 17144-17156 in October; 17334-17352, 17380 in January 1900. These had the cab moved ahead 22" in relation to the last driving axle.

Some had their tube counts reduced to 251 tubes, which yielded a total heating surface of 2,000 sq ft. A few were given 200-psi boilers and redesignated I7-j (964, 966, 977, 979) or I7-k (995, 1002); they also had their cylinders reduced to 21" diameters.

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Class I7-c, -d (Locobase 12417)

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. 39. Works numbers were:

I7-c:

1900

18135-18136, 18141-18144, 18175-18176, 18259-18260 in September

1901

February 18671-18682, 18688-1869

March 18728-18729, 18768-18769, 18788-18789, 18813-18814, 18838-18843, 18852-18853

June 19140-19143

July 19177-19178, 19216-19217, 19239-19242, 19265-19269, 19295-19297

August 19305-19307, 19323-19327

1902

October 21056-21059, 21148-21149, 21162-21163, 21174

November 21209

1903

March 21837, 21871, 21888

April 21907, 22010, 22017

May 22034, 22042, 22085-22086, 22128-22129, 22137, 22160, 22176

Clearly, the big difference between this class and the immediately preceding I7-a/I7-b was the grate, wihch measured 44% greater thanks to an 18" increase in its width as it was repositioned above the last two sets of drivers. Also, the cab was moved forward in relation to the rear drving axle so that the back wall was now 22" (559 mm) closer to the axle.

Although completed as I7-c (1900) and I7-d (1902), this class was soon converted to I7-l and I7-m; see Locobase 10853.

Some had their tube counts reduced to 237 tubes, which yielded a total heating surface of 1,921 sq ft.

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Class I7-l, -m (Locobase 10853)

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

Although completed as I7-c (Locobase 12417), this class was soon converted to I7-l. The most obvious difference was a 1-inch reduction in cylinder diameter. Some had their tube counts reduced to 237 tubes, which yielded a total heating surface of 1,921 sq ft.

A few of the class were scrapped in the 1920s. A larger portion was gradually retired during the 1930s. And immediately following World War II, the Reading scrapped the remaining I7-l/ms in June 1946.

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Class I8-a/-d (Locobase 10854)

Data from RDG 11 -1926 Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive Rail Data Exchange. Baldwin built the first 65, whose works numbers were

1905

August 26325, 26341, 26357-26360

September 26385, 26393, 26400-26401, 26413, 26418, 26438-26439, 26455, 26470-26471, 26486-26487, 26498, 26502

October 26526-26527, 26549, 26569, 26580, 26602-26603, 26615, 26634, 26713, 26732; November 26789, 26836, 26889, 26898, 26919, 26937-26938

December 26954-26955, 26963, 27012-27015, 27029-27032, 27043-27045, 27064-27065, 27080-27081, 27108, 27129, 27145-27146, 27169-27170

1906

January 27195, 27236.

Reading added 59 more. Drury notes that this class of Camelback consolidations, which was built over a nine-year period, was the most numerous on the Philadelphia & Reading. Baldwin and the railroad split orders. The drivers are relatively tall for a 2-8-0. Most were superheated (Locobase 10856), but 29 still retained their saturated boilers in 1926.

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Class I8-b (Locobase 10855)

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

This design echoed the Baldwin-built I8-a (Locobase 10854) except for the adopton of outside Walschaert radial valve gear and their production in the Reading's own shops.

By 1926, 48 I8-b and 9 I8-d had been superheated and 19 I8-b were also fitted with Nicholson thermic syphons and a few (1513, 1601, 1608 by 1926) had Nicholson thermic syphons fitted as well.

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Class I8-sb (Locobase 10856)

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

Reading began superheating the large I8-a (Locobase 10854) class not long after they entered service. The makeovers began with 1562 in 1914 and didn't end until 1550 was refitted in 1936. In addition to the relatively modest superheater installation that eliminated 161 small tubes, the design also incorporated outside constant-lead radial valve gear.

Some were refitted with smaller 55 1/2" (1,410 mm) drivers and redesignated I8-sd (See Locobase 6452).

NB: Locobase estimates the superheater area based on several other American 32-flue installations of similar length and diameter.

Also, the diagram shows a total evaporative heating surface area of 3,106 sq ft (280.19 sq m), which is much higher than the totals calculated for the combined tube and flue counts and lengths shown in the diagram. Locobase suspects the Reading updated the original I8 diagrams (represented in Locobase 10854), which had substantially greater numbers of 2" tubes, but didn't calculate the new areas.

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Class I8-sd (Locobase 6452)

Data from Reading erecting diagram of 12 May 1916, which shows evaporative heating surface only.

These nine locomotives were I8-sb camelbacks (Locobase.10954) with their driver diameters reduced to 55 1/2".

NB: Locobase estimates the superheater area based on several other American 32-flue installations of similar length and diameter.

Also, the diagram shows a total evaporative heating surface area of 3,106 sq ft (280.19 sq m), which is much higher than the totals calculated for the combined tube and flue counts and lengths shown in the diagram. Locobase suspects the Reading updated the original I8 diagrams (represented in Locobase 10854), which had substantially greater numbers of 2" tubes, but didn't calculate the new areas.

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Class I9-sa/I9-sb (Locobase 1388)

Data from comparative table of Consolidations in Railway Age 13 May 1921. See also DeGolyer, Volume 57, pp. 317+. Works numbers were 49351, 49401 in July 1918; 49475, 49635-49636, 49662 in August; 49733, 49825 , 49859 in September; 50131 in October; 50878, 50992 in December; 51084, 51172-51174, 51194-51195 in January 1919; 51345 in February; 51485 in March, 52396-52398 in September; 52445-52447; 52494-52498, 52521-52524, 52556-52557, 52579-52582 in November; 52606-52614 in December;

53989, 54023, 54128-54129 in November 1920; 54176-54182 in December;

54327-54328, 54368-54376, 54487, 54510 in January 1921; 54545 in February;

55357 in April 1922; 55405-55410, 55463-55466, 55469 in May; 55472 in June; 55504-55505, 55543-55548 in July; 55618-55621 in September.

These Reading engines had a Wooten firebox, but a conventional cab. Interestingly, some of the I-9s were "USRA" engines. The difference between these and the USRA designs is that the USRA was merely the ordering entity while the Reading supplied the design. The principal difference according to the Reading was that I9-a had a Standard power stoker while the I9-b was fitted with a Duplex stoker. Thirteen-inch (330 mm) piston valves supplied steam to the cylinders.

According to a Railway Mechanical Engineer article of April 1919, the firebox heating surface included 71 sq ft (6.6 sq m) in the combustion chamber. (Another 28 sq ft/2.6 sq m came from the arch tubes.) RME's analysis noted the differences between these 2-8-0s and some Reading Mikes that had entered service a year earlier. "It is evident that there is a considerable sacrifice in heating surface area ..." The writer goes on to note that in heavy drag service "...high tractive effort at low speeds is the controlling factor rather than a high sustained horsepower capacity."