Data from American v English Locomotives, Correspondence, Criticism, and Commentary respecting Their Relative Merits (New York: Robert K Pease, 1880), pp. 36-37.

The publication of which the edition used by Locobase was a reprint was a document presented to both Houses of the General Assembly of New Zealand by Command of His Excellency in 1878. At issue was how the demand for motive power on New Zealand's railways should be met - through the purchase of the mother country's locomotives or by continuing to buy American engines.

To back up a rebuttal to a critic of American locomotive design, W W Evans cites Zerah Colburn's 1855 test of an Erie locomotive when he was General Manager. Colburn first assembled a train of 100 cars loaded with "deals" weighing a total of 1,572 long tons and "a few feet more than half a mile long" and ran it along a nearly level (ruling grade of 0.12% or 1 in 880) gradient for 4 miles at 5 mph. On a "dead-level" 5-mile section that had gentle curves of 957-foot radius, the locomotive managed 9.7 mph. Then Colburn cut the trailing load to 30 cars weighing 514 tons and recorded the train ascending a 1 in 117.5 (0.45%) grade at 10.25 mph.

Evans concludes:"Allowing for resistances due to gravity and also to concussions and frictions of engine and train, the coefficient of adhesion must have been 1/3 the weight on driving wheels." In later measurements, the fraction of adhesion (weight on drivers divided by tractive effort) comes to 3.14. So slippery a proportion suggests a very careful manipulation of throttle and liberal use of sand in all of these trials.

Class A / D-1 (Locobase 359)

Data from Westing's Erie Power (1970), tables in December 1894 American Engineer and Railroad Journal (AERJ), and the Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

30 engines built by Brooks, Danforth, Grant, and the Erie's own Susquehanna shop from 1880 to 1882.

Class A / D-16 (Locobase 9227)

Data from Westing's Erie Power (1970) and Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Originally the Atlantic & Great Western, this line was an important component in the Erie system and spent much of its life leased to the Erie, in receivership, or both. 1882 saw a much deeper involvement in the Nypano (as the NY, P & O was more familiarly known) that culminated years later in the retirement of NY, P & O securities in favor of Erie paper.

As Edward Harold Mott described the union in Between the Ocean and the Lakes: The Story of Erie (1907)

" The long-conflicting, costly, and harassing relations of the Erie with this railroad were at last set at rest forever by an agreement whereby the Erie should operate the road at a fixed annual rental until it could be sold under foreclosure proceedings and reorganized into the Erie system. After due proceedings in the courts, the property was sold at public auction February 25, 1896, and purchased by a committee in behalf of the Erie."

During its "separate" existence, the railroad's shops at Meadville and Galion built this class of Eight-wheelers. They were slightly larger versions of the design that would later be classed as D-17; see Locobase 9226.

Class A / D-2 (Locobase 360)

37 engines built at Susquehanna shops (except for 458, built by Grant) from 1882 to 1885. Compared to the D-1s, these had much bigger fireboxes, originally had boiler pressures between 100-115 psi.

Data from Westing's Erie Power (1970) and tables in December 1894 American Engineer and Railroad Journal (AERJ).

Class B / D-3 (Locobase 361)

Data from Erie 1907 and Alvin F Staufer's Erie Steam Locomotive Diagrams supplied in May 2005 by Allen Stanley from his extensive collection.

90 engines built from 1879 to 1885 in the Susquehanna shop, Grant, Dickson, and Jersey City. Boiler was smaller than the D-2.

Class CA & CE / D-17 (Locobase 9226)

Data from Westing's Erie Power (1970) and Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Although these homebuilt Eight-wheelers had small grates and boilers even for the mid-1870s, they stood relatively high in the amount of weight they put on their drivers. And they showed a good amount of tractive effort. The NY, P & O shops would add to the stud with engines later classified as D-16s; see Locobase 9227.

Class D-12 (Locobase 9223)

Data from Westing's Erie Power (1970) and Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

The first high-drivered Eight-wheelers on the Erie came into service in 1896 (See Locobase 9221) and built new by the Susquehanna shops. Three years later, Meadville shops came out with 4 of their own. The table at the front implies that these were rebuilds of D-9 (Locobase 9222), which were smaller and older.

Locobase finds that unlikely, given the larger grate and bigger boiler, the latter pressed to a much higher pressure. Moreover, there's one more D-12 than there were D-9s. So these are new Express engines to go with the D-11s supplied by Susquehanna.

Class D-13 / E B Thomas (Locobase 9217)

Data from Westing's Erie Power (1970) and Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Class D-14 (Locobase 9224)

Data from Westing's Erie Power (1970) and Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

This locomotive was converted by Cooke to a cross-compound layout, according to Westing, but the cylinder dimensions are not given, or what we see in the diagram is the HP cylinder only. In any case, it was a "one-off".

Class D-15 (Locobase 9225)

Data from Westing's Erie Power (1970) and Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Two D-9s were converted by Baldwin as Vauclain compounds; their HP cylinders measured 12 1/2" diameter, the LPs only 21". The compounding ratio thus was a hefty 2.85. It can't have been too long before the engines were simplified as shown in the specfications.

Class D-18 (Locobase 9228)

Data from Westing's Erie Power (1970) and Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

The Pennsylvania Coal Company bought these two camelbacks (works #8717, 8725) from Baldwin with an obvious eye toward operating mountain-oriented local passenger service. They were rebuilt by Dickson in 1896 ( that's what this entry's specifications describe) and later taken into the Erie when that railroad bought the E & WV from Pennsylvania Coal.

Class D-4 (Locobase 362)

Although classed as D-4s, the first of these engines preceded the earlier D-series engines. The D-1s that succeeded them had larger boilers and 18 x 22 in pistons. 72 D-4s were built in Susquehanna, Brooks, Manchester, and Dickson.

Class D-5 (Locobase 363)

Data from Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Much larger 4-4-0 and one of the last for the Erie. The wide grate indicated the camelback layout, which has the steam dome behind the cab. These two engines started out as New York & Lake Erie engines 66-67, built by Danforth, Cooke and delivered in 1880. Baldwin rebuilt them for the Erie. 386 was scrapped first in March 1913 with 385 following in December 1920.

Class D-6 (Locobase 6695)

Data from Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

This was a large class of camelback Eight-wheelers. The tiny HP cylinders limited the whole Vauclain compound system's ability to handle the steam. Most were converted to simple expansion in several variants. One such conversion resulted in dimensions identical to those of the D-5 (see Locobase 363). Others were more substantially altered; see Locobase 6696 and 6697.

Class D-6/D-7 - simple, D flue (Locobase 6697)

Data from Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Converting the D-6 class of camelback Eight-wheelers led to three different versions. This one is identified on the diagram as having a D flue sheet (as opposed to the straight flue sheet shown in Locobase 6697). The diagrams raise many questions. How can this version, which has a few fewer tubes than the straight flue version, but of larger diameter, have had so much less heating surface?

Class D-6/D-7 - simple, strt flue (Locobase 6696)

Data from Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

This was a large class of camelback Eight-wheelers. When the D-6 Vauclain compounds were simpled, three different versions resulted. This one is identified on the diagram as having a straight flue sheet (as opposed to the D flue sheet shown in Locobase 6697). Locobase does not know why a "straight flue sheet" would result in so many fewer tubes and so small a firebox, even though the overall heating surface area rose.

Class D-7 (Locobase 9218)

Data from Westing's Erie Power (1970) and Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection. Works numbers 15231-15240, 15279-15282, 15295-15300, 15311-15315, 15420-15428, 15441-15446, 15451-15455.

The Erie threw itself into compounding and extended its reach to these small Americans. Note the small size of both the HP cylinders and the boiler tubes; see Locobase 6697 for another version.

Like the D-6s, these were soon simplified; see Locobase 9219.

Class D-7 - simple, combustion chbr (Locobase 9219)

Data from Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

As noted in Locobase 6695 and 6697, simplifying the Vauclain compounds that had been created out of earlier locomotives took several forms. The D-7 compound that was the source of the current entry (see Locobase 9218) originally had 2" tubes. A variant not reflected in the D-6 series was one in which a combustion chamber added some heating surface to the firebox, but reduced tube length and consequently required more of the tiny 1 1/2" tubes.

Class D-9 (Locobase 9222)

Data from Westing's Erie Power (1970) and Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

This quintet from Rogers followed the pattern of Eight-wheelers on the Erie at the time. One odd holdover was the small grate, however, which matched the size of engines bought a decade earlier.

Class K / D-8 (Locobase 6014)

Data from Westing's Erie Power (1970), Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection, and tables in December 1894 American Engineer and Railroad Journal (AERJ).

AERJ noted that at that point this class was in heavy commuter service with local expresses. Also used for division work in express service.

Class M / D-10 (Locobase 9220)

Data from Westing's Erie Power (1970) and Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Among the Eight-wheelers turned out by the Erie's Susquehanna shops was this duodecade of relatively large locomotives with equally sizable grates.

Class Q / D-9 (Locobase 6016)

Data from Westing's Erie Power (1970) and tables in December 1894 American Engineer and Railroad Journal (AERJ). Westing says the driver diameter was 68", but the diagram accompanying the AERJ table shows 62".

Class X / D-11 (Locobase 9221)

Data from Westing's Erie Power (1970) and Erie 1907 locomotive diagram book supplied in May 2005 by Allen Stanley from his extensive collection.

Most of the Erie's assortment of Eight-wheelers were mixed-traffic engines, but this pair were intended for express passenger service. Built at the Susquehanna shops, they were followed 3 years later by 4 similar locomotives with bigger cylinders; see Locobase 9222.