Gresley Pacifics
modifications to
Raven A2
& W1 class


A4

Update 2016-11-13
Steamindex home page

Other Gresley designs are considered separately

4-6-2

Al (later Al0) and A3:
Since the difference between the types was relatively slight, the two classes are surveyed together.

Al :1922:
This design formed the last GNR project, but the real history of the class belongs to the LNER. It stands as a milestone in locomotive development as the first successful British Pacific design. Further, it formed the basis for Gresley's "big engine" policy. In about 1915 had been considering a four-cylinder Pacific with the inside valves to be driven via rocking shafts and large Atlantic No. 279 was rebuilt to test this configuartion..

Great Northern Railway: new three-cylinder 4-6-2 express passenger engine. J. Instn Loco. Engrs., 1922, 12, 4-6. illus., table
Dimensions compared with Atlantic type.
Great Northern Railway three cylinder 4-6-2 express engine. Loco. Rly Carr. Wagon Rev., 1922, 28, 91
No. 1470
GREAT Northern Railway-three cylinder Pacific type passenger engine. Engineer, 1923, 135, 90; 452 + 2 double plates (between pp. 94/5 & 448/9). 7 diagrs., (incl. s. el.), plan.
Groves, Norman. Great Northern locomotive history. Volume 3B. 1911-1922. The Gresley era. RCTS, 1992. 132pp.
The work was completed after the death of the author. This part deals solely with the Gresley designs during the Great Northern period: in the case of the Pacifics this was extremely brief and is covered on pp 86-100. It is, however, an excellent source for rare early photographs.
NEW Pacific type locomotives, London & North Eastern Ry. Loco. Rly Carr. Wagon Rev., 1924, 30, 363 + plate on f.p. illus.
Series of twenty built by the North British Locomotive Co. to meet the composite loading gauge. Also the naming ceremony of No. 2563 William Whitelaw.
"PACIFIC" type express passenger locomotives, London & North Eastern Railway (Great Northern Section). Rly Engr., 1923, 44, 95-100 + folding plate. 4 illus., 4 diagrs., plan.
THREE-CYLINDER 4-6-2 locomotive, Great Northern Railway. Rly Mag., 1922, 43, 176-80. 9 illus., 2 diagrs. (s. & f. els.)

The British Empire Exhibition:
L.N.E.R. 4-6-2 three-cylinder locomotive. Engineering, 1924, 117, 535-9 + 4 plates. 6 illus., 13 diagrs., plan.
Flying Scotsman (4472) was an exhibit at the Exhibition. Includes sectionalized diagrams. There must be further references to this event, including official catalogues of the Exhibition.. RCTS Locomotives of the LNER Part 2A Plate 5 shows the locomotive at the Wembley Exhibtion coupled to what the caption states to be a K3 class type six-wheel tender (NER type).
Harvey, D.W. Bill Harvey's 60 years of steam. 1986.
Pp. 22-3 as an apprentice at Doncaster assisted in the preparation of the locomotive for exhibition: photograph shows it in paintshop fully burnished prior to Gresley insisting upon a reduction in the shine!

Hammer blow

Gribble, C. Particulars of locomotives employed in the tests and of others examined for the Committee. Appendix D. Department of Scientific & Industrial Reserch. Report of the Bridge Stress Committee. London: HMSO, 1928.
Although Gribble made no specific mention of the advantage to be gained from three-cylinder designs several data were presented for members of the A1 class. For  the whole engine at 5 revolutions per second were 1.37 and 1.72, 2.52 and 1.72 for each of the coupled axles. At 6 rps the whole engine figure rose to 2.3 and the maximum on any axle 2.6 tons..

A3:1927
Two locomotives were re-boilered with 220 lb/in2 boilers. One locomotive retained 20 in diameter cylinders; the other had its cylinders lined up to 18¼ in (19 in diameter was eventually standardized, for subsequent reconstruction). The superheating area was also increased and details of the changes in valve travel were also released.

[Al 4-6-2 No. 4480 Enterprise rebuilt with a 220 lb/in2 boiler.]  Loco. Rly Carr. Wagon Rev., 1927, 33, 298.
HIGHER steam pressure on the L. & N.E. Ry. Loco. Rly Carr. Wagon Rev., 1927, 33, 343-4. illus.
L.N.E.R. 4-6-2 locomotive rebuilt with high-pressure boiler. Rly Mag., 1927, 61, 2824. illus., 2 diagrs. (s. els.)
L. and N.E. Rly. locomotive with high-pressure boiler. Engineer, 1927, 144, 237. illus., diagr. (s. & f. els.)
NEW Pacific type locomotives, L. & N.E. Ry. Loco. Rly Carr. Wagon Rev., 1928, 34, 345-6.
NEW 4-6-2 locomotive, L.N.E.R. Rly Mag., 1928, 63, 350 + plate f.p. 341. illus.
This and the preceding reference both refer to the A3s built as new locomotives.

A1/A3 :
The remaining sections apply to both classes. It should be noted that the difference between the classes was one of boiler pressure, not valve events. This latter modification was made very rapidly, but the last low pressure locomotive lasted until 1948.

1925 : Westinghouse brake gear fitted for working on the North British section.
L.N.E. "Pacific" locomotive No.2571. Rly Mag., 1925, 56, 351. illus.

Materials
Johnson, W. Arnold. Alloy steels for locomotive construction. Proc. Instn Mech. Engrs., 1929, 117, 1087-97.
Awarded a prize of £5 for this Paper, which was read before the Graduates' Section, North Western Branch, in Manchester on 11th October 1928. Alloy steels considered included those with vanadium; chromium-vanadium. The high-tensile steel used on the LNER Pacific locomotives has the following composition: carbon, 0.33%; silicon, 0.21%; manganese, 0.60%; sulphur, 0.032%; phosphorus, 0.039%; nickel, 3.42%; and chromium, 0.60%. It has a tensile strength of 58 tons: this waas employed high-tensile alloy steel connecting- and coupling-rods. This contributed to reducing hammer-blow..

1928 : Corridor tenders
These tenders were introduced to enable the Edinburgh to London run to be completed non-stop. They were subsequently transferred to the A4 class.

INAUGURAL London (King's Cross)-Edinburgh (Waverley) non-stop runs, L.N.E.R. Rly Mag., 1928, 62, 461-7.8 illus., plan.
L. and N.E. Rly.— corridor tender. Engineer, 1928, 145, 666-7. diagrs.
Sectionalized diagrams are included.
LONDON to Edinburgh non-stop new L.N.E.R. train services and the first corridor tender. Rly Mag., 1928, 62, 371-4.5 illus.
NEW corridor locomotive tenders, L.N.E.R. Rly Engr. 1928, 49, 164-5. 4 illus., diagr. (s. el.), plan.
NON-STOP locomotive runs. Rly Engr, 1928, 49, 198.
Editorial comment
The NON-STOP train to Edinburgh, L. & N.E. Ry. Loco. Rly Carr. Wagon Rev., 1928, 34, 140-1. 2 illus.
Corridor tenders for Flying Scotsman service. Illustration shows No. 4472 Flying Scotsman locomotive. Also description of rolling stock with hairdressing saloon, ladies' retiring room and new restaurant cars with all-electric kitchens.
Seaton, Douglas. London and Edinburgh non-stop, The Flying Scotsman". Loco. Rly Carr. Wagon Rev., 1928, 34, 176-7.
Portrait of Driver Pibworth, Sir C. Batho, Lord Mayor of London in top hat, and Gresley wearing a bowler both of latter on footplate on No. 4472 prior to departure of inaugural non-stop Flying Scotsman. Seaton observed a punctual arrival in Edinburgh on 1 May and on the following day a punctual arrival back in London, although a severe signal check near Selby caused concern on the return run.

1928: Feed water heating: Experiments with the Worthington system.

An IMPROVED locomotive feed-water heater and pump. Loco. Rly Carr. Wagon Rev., 1928, 34, 225-7. 2 illus., 2 diagrs.

1929: Feed water heating: Experiments with A.C.F.I. apparatus.
Two Pacifics fitted: one of which was No. 2580 Shotover. Space limitations on top of boiler forced the location of the water reservoirs to be inside the smokebox
IMPROVED type feed water heating apparatus, L.N.E.R.: particulars of the new A.C.F.I. apparatus fitted to two of the Pacific type locomotives. Rly Engr. 1929, 50, 442-4. 2 illus., 3 diagrs.
LOCOMOTIVE feed-water heater. Engineer, 1929, 148, 632. 2 illus., diagr. (s. & f. els.), plan.
L. & N.E.R. Pacific type locomotive fitted with A.C.F.I. feed-water heating apparatus. Loco. Rly Carr. Wagon Rev., 1929, 35, 277.2 illus.

1929 : Raven a.t.c. apparatus:
Modification to this apparatus was required for locomotives operating over the Forth Bridge : an un-titled paragraph exists
Rly Mag., 1929, 64, 503.

1931: Hinged look-out side window
Lancegaye non-splinterable glass fitted to cab side window on Pacific No. 4478 to provide protection to engine men
Loco. Rly Carr. Wagon Rev., 1931, 37, 173.

1932/33: Smoke deflection:
Nos 2747 and 2751 were modified experimentally. The alterations affected the upper part of the smokebox, which was cut-away and replaced by a sloping plate. On No. 2747 the cylindrical shell and chimney were retained, but on 2751 the shell was removed and a stove pipe chimney and small, adjacent deflector plates were fitted. The object of these modifications was to funnel the draught to behind the chimney. See also Windle's observations.

No. 2747: Rly Mag., 1932, 70, 75. illus, p. 207.

No.2751. Rly Mag., 1932, 71, 74: 1933, 72, 466.

1933: roller bearings for valve gear.

Roller bearings for locomotive valve gear. Loco. Rly Carr. Wagon Rev., 1933, 39, 132.
Supplied by Ransome & Marles Bearing Co. Ltd. of Newark-on-Trent.

Testing and performance.

1925 : Interchange trials:
The railway exhibits at the British Empire Exhibition had included Al and "Castle class locomotives. After the close of the exhibition comparative trials of the types were arranged by the LNER and GWR managements. The results showed that the Great Western locomotive was superior in terms of performance and fuel consumption. This relative failure of the Pacific design induced Gresley to permit Bert Spencer to redesign the motion by introducing long lap valves. C.J. Allen has chronicled these tests in a number of contemporary and retrospective accounts. His The London & North Eastern Railway is of special interest in that it analyses the reasons behind the origin of the trials (see pp. 118- 23). Allen's Two million miles of train travel quotes some of the author's personal involvement, especially the Great Western's objection to a contemporary radio broadcast on the subject (Allen was an LNER employee!). KPJ would like a full reference to The Great Western Magazine account..

Allen, C.J. British locomotive practice and performance. Rly Mag., 1925, 57, 47-57; 151-63.
Allen, C.J. The locomotive exchanges, 1870-1948. [1949].
Allen, C.J. The London & North Eastern Railway. 1966.
Allen, C.J. Two million miles of train travel. 1965.
The exchange trials of locomotives. Engineer, 1925,139, 627-8.
Editorial comment on the GWR test report.
Harrison. in Peter Towned. LNER Pacifics remembered. Chapter 9.
Observes that Castle class was near zenith of Churchward's design strategy whereas Gresley's A1 was at early stage of its development during the 1925 interchange trials. Furthermore, Driver Young (GWR) deliberately ignored speed restrictions..
Harvey, D.W. Bill Harvey's 60 years of steam. 1986.
Pp. 52-3: soon found that firing a wide firebox demanded quite a different technique from that required for a narrow box; the secret of success was to keep the back corners well packed up so that these fed the rest of the grate. The technique for stoking the back corners of a locomotive with a wide grate when firing through the narrow opening of the LNER trap type firebox, as developed over the years by GN firemen, was to swing the shovel blade in an arc right through the firehole, dropping at the same instant the front or guiding hand and finishing with a smart flick of the wrist of the other hand, so tipping the coal into the corner. Needless to say the metal shank of the shovel soon became too hot to handle unless a cloth or glove were used on the guiding hand, while blistered knuckles on the propelling hand was the penalty for any lack of smartness in withdrawing the blade!
Pp. 93-5: On 24 October 1940 No. 2501 Colombo suffered a collapse of the middle big end due to a failure in maintenance of the warning fluid in wartime conditions: this led Harvey to modify the container so that it could be replenished. (diagram).
Pp. 110 et seq
Collaboration with Bert Spencer to examine design weaknesses, especially those emphasised by wartime working: "A start was made with those common to all areas, the Pacific and V2 classes. All the principal depots on the East Coast main line between King's Cross and Edinburgh (Haymarket) were visited in turn and the views and suggestions of the maintenance staff canvassed. All complained of the deterioration in performance of the middle big-end and its tendency to run hot when subjected to additional loading caused by wear in the pins of the 2-1 gear due to ingress into their bearings of smokebox ash. The 2-1 gear was a simple and ingenious arrangement of two levers connecting the right- and left-hand valve gears in such a way that their combined motion gave a correct steam distribution to the middle valve, thus dispensing with the need for a separate inside valve gear. All advantages have corresponding disadvantages – any lost motion caused by wear in either of the outside gears was also imparted to the middle valve thereby increasing its port opening to steam and consequently the loading on the middle big-end. Over-running of the middle valve occurred at high speed due to whip in the two primary valve motions when these were subjected to heavy inertia forces. In peacetime with good maintenance and regular and thorough greasing, wear was easily contained within acceptable limits. The principal causes of excessive wear under war conditions were the ingress of fine smokebox ash into the bearings and over-long intervals between greasing. We recommended as a temporary expedient until pre-war standards of maintenance could be assured that an oil lubricated plain bearing of the largest possible diameter (which could be given attention by the driver) be substituted for the existing grease-lubricated main fulcrum roller bearing, also that special attention be given to making the footplating and inspection door above the 2-1 gear ash proof. Twenty-one items in all were listed for attention ranging in importance from those just described, down to the allegedly poor war-time quality of the india rubber neck ring bushes used in vacuum brake cylinders, the short life of which we found was not caused by inferior material but to locomotives awaiting disposal standing over heaps of live fire carelessly dropped in the four foot.
Regarding the middle big-end about which so much has been written in recent years, the evidence produced at the depots we visited confirmed my opinion that the semicircular strap was weak and was flexing under load, thereby distorting the brasses and causing these to nip the journal and so cause heating. Proof that flexing occurred was afforded by the fact that when a centre big-end was taken down for examination the jaws of the two brasses were invariably bright and polished where one had fretted against the other – likewise the surfaces of the bronze shims or gluts used for adjustment. More convincing proof was the fact that whenever a brass was found broken in two, as happened occasionally, it was always the back brass that broke, never the front brass, although the front was weakened by a %in keyway'" preventing the circular brasses from rotating. The polished) appearance of the fractured surfaces caused by fretting was convincing proof that the strap flexed. The design of the middle connecting rod and strap closely resembled on a larger scale that in a high class automobile engine and was a magnificent piece of forging and machining. Possibly its designer had such a prototype in mind but overlooked the fact that whereas an internal combustion engine was single-acting and the strap therefore carried little or no load, in a double-acting steam engine this was not so, for the loading was the same on both brasses, for which the strap as designed was ill-suited, being at its weakest at the point where it needed to be the strongest.
I had been much impressed by the excellent design of rod ends that I had seen on German locomotives. These were of T-section with a deep crescent-shaped rib or web at the back in order to resist deflection. This was the design that we recommended and which was ultimately adopted as the standard - not quite as we wanted, as the rib was made concentric instead of crescentshaped, but still a good deal stiffer than the original design.
This improved pattern may be seen on nearly all the Gresley three-cylinder locomotives that have been preserved. Prior to this, several alternative designs of big-ends for three-cylinder locomotives had been produced under Edward Thompson's direction but those seemed to be singularly unattractive in design, - being heavy and clumsy. An interesting aspect of our enquiries was the diversity of opinions expressed on minor points of design, troubles experienced at one depot with certain fittings being almost unknown at another.
An increase in the number of heated coupled axle boxes on Pacifics and V2s also came under scrutiny. These 50 pattern axleboxes had a large bearing area and before the war seldom gave trouble with heating. It was suggested tha~ lowering the rape content in the oil from 25% to 15% was responsible, but as this lower rape content oil was proving satisfactory under axlebox loading conditions much more severe than on the Pacifics or V2 classes there had to be some other cause. This was traced eventually to a change in Works procedure, in that the timehonoured (and time-consuming) practice of bedding axleboxes onto their journals by hand had been abandoned as a wartime economy measure. Instead, axleboxes were now bored out 0.014in larger than the journal and put on without fitting. This method resulted in the bearing having little more than line contact with the journal, causing the early development of knock and a liabi1ity to heat. A reversion to pre-war practice was therefore our recommendation.
A feature that formerly characterised the Gresley three-cylinder locomotives, the musical clang produced by the resonant lightweight alloy steel coupling and connecting rods which rang like a bell when struck with a hammer, disappeared in later years when these were replaced by rods made from ordinary carbon steel. The adoption of heat-treated nickel-chrome steel with a tensile strength of 60 tons for the motion of Gresley locomotives instead of ordinary 32.37 tons carbon steel succeeded in reducing by more than one-third the weight of the revolving and reciprocating masses, with a consequent reduction in rail hammerblow. This innovation stood the LNER in good stead in later years, for no alteration in wheel balance was necessary when alloy steel became unobtainable and heavier rods made from carbon steel had to be substituted, because this increase in weight was offset by a 'corresponding reduction in the reciprocating balance from 65% to 40%. The fact that O.V.S. Bulleid had eliminated reciprocating balance entirely in his own threecylinder Pacifics, no doubt influenced Doncaster in making this change from hitherto accepted practice. These are the rods seen today on those Gresley locomotives that have survived, and although much lighter and more elegant than those fitted to BR standard locomotives of comparable power, they do seem to me heavy in appearance when I recall the beautifully light originals with webs only 3/8in thick.
Hills, Richard L. Power from steam. 1989.
Here it is interesting to note that the Great Western Railway, which used Welsh coal in its locomotives, retained a narrow firebox for its most powerful 4-6-0 King class engines in 1927 whereas the London & North Eastern Railway employed a wide firebox for the 4-6-2 Flying Scotsman in 1923 because the calorific value of its coal was not so high.
Hughes, G.J. Not a fair trial? some reflections on the GWR/LNER Locomotive Exchange of 1925. Rly Wld., 1981, 42, 638-42.
The story of the Locomotive Exchange between the GWR and the LNER following the Wembley British Empire Exhibition in 1924 where Caerphilly Castle was exhibited alongside Flying Scotsman is well-known and is well-covered in C.J. Allen's The locomotive exchanges (as is stated  by the Author), but Hughes brings out certain deatils which are less well-known, especially the looseness of the management structure on the LNER where Alex Wilson, Divisional Manager of the Southern Area appears to have been closely involved with Sir Felix Pole in aranging the trial and without ensuring that Gresley was able to supply the best motive power, especially for the runs on the ECML. On the GWR Driver Pibworth and Premium Apprentice Eric Trask (who broke up the coal) ensured that the Pacific's magnificent boiler was exploited in extremely fast uphill running to compensate for the slow downhill running dictated by the poorly laid Great Western track. On the LNER very fast running by the GWR crew (both uphill and at inappropriate points, such as the approach to Peterborough observed by J.F. Harrison) and Pacifics in run-down condition driven badly ensured that the GWR had a terrific victory.
Interchange trials of passenger locomotives on the Great Western and London and North Eastern Raliways. Loco. Rly Carr. Wagon Rev., 1925, 31, 142. illus.
Actual test performance.
Le Fleming. Hugh M. International locomotives. Plate 68
Painting of No. 2575 Galopin in pre-WW2 apple green livery
The locomotive exchanges. Rly Engr, 1925, 46, 199-200.
The locomotive trials. Engineer, 1925, 139, 492. Erratum p.519.
Rather cautious editorial comment.
Nock, O.S. British locomotives of the 20th century. Volume 1. 1900-1930. 1984.
On page 86 Nock wrote that the Chairman [of the NBR], William Whitelaw, always seemed to enjoy the prospect of comparative trials (which actually extended beyond the life of the NBR), and noted the large number conducted on the NBR (GWR 2-8-0, NER T3 and T2 and LNWR Precursor). This may be relevant to the not much later Castle/A1 trials.
Nock, O.S. The Gresley Pacifics. Newton Abbot: David & Charles, 1982
Of interest for noting Trask's involvement and comments upon the trials: notably that the Pacific did withstand the very poorly aligned track on the Great Western, and that this must have contributed to the slower running thereon, and Gresley's disappointment at the high coal consumption and relatively slow running on the Western.
Official statements as to results [by the Companies concerned]. Rly Mag., 1925,57, 57-9.
Poultney, E.C.  Locomotive performance and its influence upon modern practice. J. Instn. Loco. Engrs, 1927, 17, 172-261. Disc.: 261-72. (Paper No. 213)
General assessment of class alongside other British and other contemporary locomotives
Results of interchange locomotive trials, London and North Eastern and Great Western Rys. Loco. Rly Carr. Wagon Rev., 1925, 31, 196.
Some inaccurate reasons were stated for the failure of the A1, such as the use of ejectors on the L.N.E.R. in preference to vacuum pumps.
Voyageur, pseud. The locomotive exchange : London & North Eastern "Pacific" v Great Western "Castle". Rly Mag., 1925, 56, 478-82. 4 illus.

1931 tests
To test the speed capacity of the latest Pacific type locomotives a series of trial runs had been organised between Peterborough and King's Crass On 10 December 1931 the train due at King's Crass at 16.30 headed by engine No. 2547 Doncaster, with a load of 224.5 tons (tare), covered the 76 m. 29 c. in 1 hour 6 minutes 10 seconds, an average speed of 69.2 mile/h. This included a slack to 10 mile/h, just south of New Southgate, where a new bridge was under construction far an arterial road. Locomotive Mag., 1932, 38, 34

1934: Evaporative tests:
The ultimate steaming capacity of the boiler was determined by stationary tests at Doncaster Works.

TESTS of a locomotive boiler. Engineer, 1934, 158, 118-20. 2 illus., 3 diagrs.

1934 : King's Cross-Leeds test run:
No. 4472 Flying Scotsman is in many ways the epitome of the immortal locomotive. It was displayed at the Wembley Exhibition in 1924 and in 1934 it was the subject of a high speed trial run from London to Leeds and back. On the return trip a speed of 100 mile/h was achieved—the first fully authenticated occurrence in Britain. At last (April 2004) this locomotive forms part of the NRM Collection

Allen, C.J. A new "record of records" : London to Leeds in 2 hours 32 minutes. Rly Mag., 1935, 76, 6-11. 2 diagrs., table.
HIGH-SPEED railway runs. Engineer, 1934, 158, 590-1. 2 diagrs. (incl. s. & f. els.), tables.

1935 : King's Cross-Newcastle test run:
This served as a "dress rehearsal" for the Silver Jubilee service. On the return journey a speed of 108 mile/h was attained. No. 2570 Papyrus, one of the locomotives rebuilt with a 220 lb/in2 boiler, was used for this test.

Allen, C.J. The L.N.E.R. world records: l08 m.p.h. maximum and 300 miles at 80 m.p.h. Rly Mag., 1935, 76, 238-43. diagr.,  5 tables.
FURTHER details of the L.N.E.R. record run. Rly Gaz., 1935, 62, 501-2. diagr.
Includes coal consumption figures and reproductions of the diagrams for speed recorded in the dynamometer car.
The LOCOMOTIVE that holds the world speed records. Rly Gaz., 1935, 62, 509. illus.
A WORLD'S record on the L.N.E.R. Rly Gaz., 1935, 62, 466-7.3 tables.

1937 : Centre of gravity tests:
One A3 class locomotive was tested to see if its calculated centre of gravity agreed with actuality.

LOCOMOTIVE centres of gravity. Loco. Rly Carr. Wagon Rev., 1937, 43, 212-13. 2 illus., diagr.

Retrospective and critical material:
These Pacifics rank with four or five other designs as being the most popular ever to run in Britain. This popularity is exemplified by the fact that a private individual (A. Pegler) was prepared to buy Flying Scotsman to save it for posterity (see "Mr. Pegler's Pacific"). This section is as written in 1969 and there has been much further material published, but nothing to compare with the ultimate acquisition of Flying Scotsman by the NRM.
C.J. Allen's two books form useful accumulations of material which is other wise scattered, but they lack some of the detail found in contemporary records. Ransome-Wallis' article is noteworthy for the extensive details of post-war developments.
The papers by J.F. Harrison and O.V.S. Bulleid include short appreciations of this class, and are of importance in that they represent the design viewpoint. A highly articulate engine-driver, N. McKillop, must also be regarded amongst the premier authorities on this locomotive type. In order to set his writings into perspective it is necessary to note that he was employed at Haymarket Shed, Edinburgh, where enginemen were assigned to individual locomotives. McKillop's charge was No. 60100 Spearmint, and from the experience gained in handling this locomotive he developed a reasoned admiration for the class. This relationship between man and locomotive has been described in a number of articles and books.

Allen, C.J. British Pacific locomotives. 1962.
A list of errata is given in a letter by P.J. Coster: "The L.N.E.R. Pacifics" (J. Stephenson Loco. Soc., 1963, 39,17-18). The author rates this as his best work. [Two million miles of train travel (1965)] and the only appreciable omissions are the diagrams found in contemporary accounts.
Allen, C.J. The Gresley Pacifics of the L.N.E.R. 1950 .
The section on Gresley Pacifics in British Pacific locomotives (1962) is a slightly expanded version of this monograph. The cab diagrams, elevations and many illustrations were not incorporated in the later work, however.
Atkins, Philip. Flying Scotsman: LNER classes A1/A3 Pacific No. 4472, 1923 onwards: am insight jnto maintaining, operating and restoring the legendary steam lcomotive, Sparkford: Haynes Publishing/National Railway Museum, 2016. 172 pp.
The accent is on the preserved locomotive and its restoration.
Atkins, Philip. Odious comparisons. Steam Wld, 2015, (335), 8-14
Annual mileage: 78,000 in 1937 and 46,000 in 1950
Bannister, Eric. Trained by Sir Nigel Gresley. 1984. pp, 27-8
Sent by Gresley to investigate nosing by Pacifics and investigated behaviour of Cartazzi slides
Baxter, F.L. Balancing of three-cylinder locomotives. Engineer, 1935, 160, 84-6. 5 diagrs., 8 tables.
Although mainly a theoretical treatise, the Al is considered on a comparative basis with other 3-cylinder designs.
Bond, R.C. Organisation and control of locomotive repairs on British Railways. J. Instn Loco. Engrs, 1953, 43, 175-265. (Paper No. 520).
Annual mileage figures (post WW2) for the class are quoted.
Bulleid, O.V.S. Locomotives I have known. Proc. Instn mech. Engrs, 1945, 152, 341-52 + 6 plates. 18 illus., 12 diagrs., 11 tables.
The Al class is one of a few select designs to be considered.
Carling, D.R. in Peter Towned. LNER Pacifics remembered. Chapter 8.
Only experienced one Pacific failure in many miles of travel between Darlington and King's Cross (1937-9 and 1946-8) and King's Cross and Glasgow (1940-5)
Clay, John F. How good were the original Gresley Pacifies? in Hughes, Geoffrey. A Gresley anthology. Didcot: Wild Swan/Gresley Society, 1994. pp.25-6.
Before being equipped with long lap valves performance was often poor except in relationship to haulage capacity. Cost of conversion was £150-190 per locomotive and coal consumption was reduced from 50 to 40 lb per mile. It would have been very costly to convert the Raven Pacifics.
Cook, A.F. Raising steam on the LMS: the evolution of LMS locomotive boilers. Huntingdon: RCTS, 1999. 233pp.
Table 50 (page 217) quotes the cost of classified boiler repairs on a comparitive basis in pence per mile in 1954: 2.7 pence/mile for a Duchess as against 0.8 for an A4, 1.5 for an A3 and 0.6 for a Merchant Navy..
Cook, K.J. The steam locomotive: a machine of precision. J. Instn Loco. Engrs., 1955, 45, 418.
Fitting of Churchward type big ends to Gresley Pacifics
Coster, P.J. An appreciation of the Gresley "A3" Pacifics. J. Stephenson Loco. Soc., 1966, 42, 71-86. 8 illus., 2 tables. Bibliog.
Duffy, M.C. Technomorphology and the Stephenson traction system. Trans. Newcomen Soc., 1982, 54,55-74. Disc.: 74-8.
Notes that Gresley's initial Pacific design would have been a failure, and it was only through Gresley's understanding of the significanace of Goss's work as expressed in American Locomotive Company's No. 50,000 that GNR No. 1470 was such a successful design.
Evans, M.  Pacific steam : the British Pacific locomotive. 1961.
Clear and concise, with a foreword by R.A. Riddles.
Gresley, H.N. High pressure locomotives in response to discussion on page 164 Proc. Instn mech. Engrs, 1925, (2), 164.
In Scotland engines were running their full time between general repairs with practically no dirt in the boiler. One of the new Pacific engines of the L.N.E.R. was stationed in the Edinburgh district, and ran between Edinburgh and Glasgow and Edinburgh and Berwick, and also to Newcastle. After running 90,000 miles it had come into the works for general repair. He was at the works at the time, and he had himself examined the firebox. It looked perfect, and not a single stay had to be renewed. If that engine had been running in England south of the Tweed, 200 or 300 stays would probably have had to be renewed after running that mileage. The total life of a firebox in Scotland was a great deal longer than that of a firebox in England.
Gresley, H.N. The three-cylinder high-pressure locomotive. Proc. Instn mech. Engrs, 1925, 109, 927-67.
Hall, Stanley. Railway milestones and millstones: triumphs and disasters in British railway history. 2006.
"The streamlined trains were a huge publicity success for the LNER and a great morale boost for the staff, who had lived through tight economic pressures. But primarily, the 'A4s' had technically outclassed even the 'A3s'. They were the glory of the East Coast expresses for the next 30 years and Gresley's crowning achievement. He was quite properly knighted in 1936."
Harrison, J.F. The gathering of the new crop. J. Instn Loco. Engrs, 1961-62, 51, 336-56.
Includes an appreciation of the Gresley Pacifics.
Herbert, T.M. Locomotive firebox conditions: gas compositions and temperatures close to copper plates. Proc. Instn Mech. Engrs, 1928, 115, 985-1006
Part of a collaborative profamme between LMS, LNER and SR and British Non-Ferrous Metals Research Association Included tests on two  Pacific class locomotives working under different conditions: one on Waverley route
Jarvis, C.C. Dynamometer car working on the L.N.E.R. J. Instn Loco. Engrs, 1933, 23, 2-33. . (Paper No. 297).
Contains brief details of two tests, namely the effect of taking up water on speed and power output and a test-run on the Waverley route (Edinburgh-Carlisle.)
Kelway-Bamber, H. Modern British express passenger engines. J. Instn Loco. Engrs, 1926, 16, 1004-17. (Paper No. 207).
Detailed comparative analysis of the A1, Castle and Lord Nelson designs; included an examination of A1/Castle running betwen King's Cross and Grantham..
McKillop, N. Enginemen elite. 1958.
Chapters 14 and 15 describe the author's experiences with Spearmint
McKillop, N. The Gresley touch. Trains Ann., 1956, 5-10. 2 illus.
[McKillop, N..] Toram Beg, pseud. The highlights that stick. Rly Wld, 1963, 24, 3-4.
Priming
[McKillop, N.] Toram Beg, pseud. The speed barrier: a footplate commentary. Trains ill., 1956, 9, 312-13.
High speed with Spearmint.
Miller, N.G.  Coasting at 25% cut-off. J. Stephenson Loco. Soc., 1956, 32, 138-9.
The reason for Gresley Pacifics coasting at 25% cut-off, rather than in mid-gear.
Miller, T.C.B. Salad days in steam. in Hughes, Geoffrey. A Gresley anthology. Didcot: Wild Swan/Gresley Society, 1994. pp. 59-65.
As part of his premium apprenticeship in 1932 the writer spent a considerable amount of time on the footplate when working a great variety of trains. One vivid memory was a trip on a K3 in darkness when the crew were thrilled at the view of glow worms in the cuting at Stoke summit.. Another memory was an extremely difficult start from Peterborough going north on 2751 Humorist with the Duke and Duchess of York on the train. There was a very fast run with 2544 Lemberg.
Miller, Terry. Examining the piston valves of a 'Castle'. in Hughes, Geoffrey. A Gresley anthology. Didcot: Wild Swan/Gresley Society, 1994. p. 35.
There have been suggestions that the LNER may have committed industrial espionage on the Castle class during the locomotive exchanges: this only considers the feasibility of removing, measuring and replacing the piston valves on a Castle: gives no indication as to whether this was done.
Neve, Eric. Early runs with the original Pacifies in Hughes, Geoffrey. A Gresley anthology. Didcot: Wild Swan/Gresley Society, 1994. pp.27-30.
Argues that performance varied with drivers - some failed to work on full regulator. Examines the quality of the drivers and locomotives selected for the exchanges with the Castle class. Argues that overall performance was better than sometimes stated.
Newsome, Norman. Gresley Pacifies and Super-Pacifics in Hughes, Geoffrey. A Gresley anthology. Didcot: Wild Swan/Gresley Society, 1994. pp.31-5.
Credits Bert Spencer with redesigning the valve gear with long travel valves. Cites Dow's British steam horses (page 110 et seq) as source of excellent descriptions of the high speed test runs and of the inaugural run on the Silver Jubilee.
Nock, O.S. The Great Northern Railway. 1958. Chapter 14,
The results of the 1923 comparative tests of Gresley and Raven Pacifics were published for the first time. At that time there was very little difference in the performance of the two types.
Railway Correspondence & Travel Society. Locomotives of the LNER. Part 2A. Tender engines—classes A1 to A10. 1978.
Ransome-Wallis, P. The Gresley class "A3" Pacifics. Trains ill., 1960, 13, 360-4: 430-5. 8 illus., 3 tables.
The later developments (i.e. post-1945) are thoroughly reviewed.
Reed, Brian. 150 years of British steam locomotives. pp. 100-1.
Continued from. Gresley's practice was progressive from the time he succeeded H. A. Ivatt on the GNR; but from the inception of his three-cylinder 2-8-0 coal engine in 1918 and the big-boiler 1000-c1ass three-cylinder Mogul of 1920 he moved definitely into new conceptions of size and power that culminated, in pre-Grouping days, in his first two A1-class Pacifics of 1922. In later years he was once asked why these two engines had been successful from the start whereas the GWR Great Bear of 1908 had been a failure. He replied: 'Because I was thinking about and scheming mine from 1914.' Yet his two Pacifies as built were back-breakers and only moderate performers for their size. Not until the GWR valve-motion and pressure principles had been incorporated did they become outstanding.
More as a publicity measure than as a considered move, the general managers of the GWR and LNER in 1925 arranged trials of a Castle 4-6-0 and a Gresley 180lb Pacific over the lines of both companies, between Paddington and Plymouth and between King's Cross and Doncaster. The 80-ton 4-6-0 had the better of the 92-ton Pacific on almost every count of haulage, speed and line performance with a 10-12 per cent economy in fuel and water. The Pacific had much the bigger boiler and the first of the modern combustion-chamber fireboxes, but its valve gear, valve proportions and setting prevented steam being used efficiently, and it was pre-eminently in this aspect that the GWR engine scored. Yet Gresley was hard to convince, and only in 1927 did Pacifies appear with revised valve motion. With the same 180psi boiler pressure, coal consumption on 400/450-ton Anglo-Scottish trains at 52mph averages came down from 52 to 38lb/mile, and at once gave possibilities of longer through runs and longer non-stop runs.
In 1928 Gresley adopted the second of the GWR principles, high pressure, by going to 220psi, for his valve gear could now deal with it. Any economy from this alteration could not be judged because at the same time 43 superheater elements were put on in place of 32; but the new engines were much more sprightly than the 180lb engines, and this new pressure, or a higher one, plus the revised valve gear, was adopted for all future main-line locomotives – 4-6-2, 2-8-2 and 2-6-2. The 220lb revised valve gear Pacifies could haul a 47 5/500-ton passenger train along the level at a mile-a-minute with full throttle and no more than 15 to 18 per cent cut-off, thus equalling for the first time the standards of performance common on the GWR from 1907-10.
The increased haulage power of the 220psi engines was necessary, for by 1930 the weight of many main-line trains had gone up from around 400 tons at Grouping to 500 tons, not because of more vehicles in the train but because of heavier stock (with greater lighting loads) which had to be hauled non-stop over the 268 miles from London to Newcastle in place of the 188 miles to York. The Edinburgh non-stops, which brought the eight-wheel non-bogie corridor tenders, were an easy proposition until 1932 for they were to a schedule of under 50mph.
Reed, Brian. LNER non-streamlined Pacifics. Loco Profile No. 1. undated.
5 tables. centre colour spread drawn by A. Wolstenholme shows A1 4472 Flying Scotsman as exhibited at British Empire Exhibition in 1924 and A3 2501 Colombo of final series. Acknowledges help from E.D. Trask, A.J. Somers, E.H. Fowkes and Peter Townend. At least in the part work original there is some very "current information" relating to the tour in the USA which may disturb today's reader..
Rimmer, Alan. Testing times at Derby: a 'Privileged' view of steam. Usk: Oakwood, 2004. 120pp. (RS14)
Found all Gresley Paqcifics to be smooth riding compared with Peppercorn A1 class. Mainly Chapter 10..
Robson, R.J. discussion on: Windle, E. Locomotive valves and valve gears.  J. Instn Loco. Engrs, 1933, 23, 474-5.
Introduced statistics relating to eight of the Gresley Pacifics which had been modified with long travel valves: these had each run over 500,000 miles and Royal Lancer had achieved 613,366 miles..
Schlegel, C.  discussion on Holcroft, H. Some points of common interest in rolling stock and permennent way. J. Instn Loco. Engrs., 1929, 19, 823-30. (Paper No. 244).
Schlegel, C.  discussion on Selby, F.W.  Compound locomotives. J. Instn Loco. Engrs., 1931, 21, 113-14. (Paper No. 257)
Mr. Selby quoted a mass of figures regarding the-performance of the compound locomotive. I should like to from my personal experience with the Gresley Pacific high-pressure simple engines that we have got down to 3.07 lbs. per draw-bar horse-power hour, which is a very good figure dealing with heavy trains and compares favourably with the rather doubtful figures of Mr. Selby, who has admitted so far as the coal consumption figures are concerned, they are calcuiated figures and not actual. . The coal consumption is the main point and not so much the water; the latter does not cost very much, but an engine heavy in coal consumption cannot be considered a success. In his comparisuns, I am sorry Selby has not taken the section of line between Edinburgh and York, rather than between King’s Cross and Leeds, as on the former we have worse gradients that those shown in the illustrations. The Pacifics are working sleeping car trains of over 500 tons through to York from Edinburgh and from Newcastle through to King’s Cross, and on the North Section have to go up one long gradient of I in 96 at an average speed of 35 m.p.h. My opinion is that if we have a perfectly reliable engine low in coal consumption without going in for the compound type, with the added advantage of less repair work, it would be a mistake to go in for compounding. To quote one case, we have a Pacific engine which worked 55 consecutive days covering 28,830 miles, an average of 524 miles per day without practically a key being put on the engine. From what I have seen of engines in France they ceem to me nothing but a mass of steam and certainly gave the impression that repairs must be pretty heavy. Perhaps Mr. Selby will say something about this. I should like to know whether it is the general practice to fit engines in France with steam chest pressure gauges in the cab.
Spencer, B. The development of L.N.E.R. locomotive design, 1923-1941.  J. Instn Loco. Engrs, 1947, 37, 222 et seq. (Paper No. 465)
Reply to question from Cox concerning the performance of copper firebox stays on high pressure boilers, the LNER had found that the stay heads in the fireboxes of the Pacific engines carrying a working pressure of 220 psi deteriorated more rapidly than those of the 180 lb. psi boiler and that the area subject to deterioration was extended, but there was no noticeable difference between the performance of the copper firebox stays on the 220 psi boilers and those on the 250 psi boilers. The firebox combustion chamber on the 250 lb. boilers was 12 in. longer than on the 220 lb. and 180 lb. boilers and would possibly have some bearing on the matter. The average mileages obtained with the 220 psi and 250 psi boilers on the Pacifics between boiler lifts was 70,000 to 80,000 miles.
Continuing with his response to questions raised by A.F. Cook and O.S. Nock on the over-running of the centre cylinder valve on engines fitted with Gresley gear Spencer noted that indicator diagrams had not been taken on the A4 class as the streamlined casing made it impracticable to find accommodation for an operator and direct reading instruments were not available, but diagrams had been taken on A3 class engines and a selection from engine No. 2751 were included on a folding diagram (Fig. 49). These showed that the area of the centre cylinder diagram is not affected to any material extent until speeds of 60 mph and over are reached at early cut-offs. Above this speed there is some difference in the power developed between the inside and outside cylinders, but the fact remains that engines fitted with this form of conjugated valve gear ran successfully and economically, in the pre-war period, some of the fastest trains in Britain.

Stephenson, H.J. Locomotive engine failures and their causes—some hints for their prevention. J. Instn Loco. Engrs, 1928, 18, 133-44. (Paper No. 223).
Includes a descripton of failures in the union link and combination lever, and attempts to eradicate them.
Townend, P.N. East Coast Pacifics at work. 1982.
Webber, A.F. The proportions of locomotive boilers. J. Instn Loco. Engrs, 1937, 27, 688-725. (Paper No. 378).
The A3 boiler is considered on a comparative basis.
Webster, H.C. Introduction to the locomotive. London, Sampson, Low, Marston, [1947]. vi, 56 p. l6diagrs.
Intended as an introductory work for children. It includes 16 fenestrated diagrams of an A3 class locomotive.
Wilkinson, W., illus. 4-6-2 three-cylinder Pacific locomotive. London, Virtue, [1935?]. folding plate, diagr.
Sectionalized diagram. Catalogued in Manchester Central Library under "London and North Eastern Railway."
Wilson, Andrew. Gresley Pacifics on the Midland: the Leeds Holbeck 'A3s'. Steam Days, 1995, (72) 462-9.
Brief period in early 1960s when performance on the Leeds to Carlisle and Glasgow services was transformed by the A3 class. Many photographs plus observations by Donald Palmer (a diesel traction inspector) and Bert Coles (a fireman). KPJ found that the A3s could out-perform the off-peak diesels and had one amazing run up to Ais Gill from Appleby on the afternoon train from Glasgow with the sweet music from the Kylchap exhaust.
Wilson, G.R.S. Report on the derailment which occurred on 1st September, 1955 at Westwood Junction near Peterborough in the Eastern Region, British Railways. Ministry of Transport & Civil Aviation : Railway accidents [monograph]. London, HMSO, 1956. 10 p. + 6 plates. (incl. 1 folding). 5 illus. diagr. (s. & f. els.), 2 plans.
This accident to the W1 locomotive indicated that the bogie stretcher bars and side frames on Gresley's Pacifics were weak.
Windle, E.
Some notes relating to cylinder performance. J. Instn. Loco. Engrs, 1931, 21, 178-97. (Paper No. 272).
This paper outlines the development of long lap valves on the LNER.
Windle, E. Discussion on Holcroft, H. Smoke deflectors for locomotives. J. Instn Loco. Engrs, 1941, 31, Pp. 490-9 (9 illus).
Pp. 490-9 (9 illus.) : the experimental modifications (see above) to Al and A3 smokebox and chimney arrangements are considered in detail.
Yeadon, Willie B. Yeadon's Register of L.N.E.R. locomotives. Vol.1 : Gresley's A1, A3 Classes.

Names

London & North Eastern Ry. Locomotive Mag., 1925, 31, 140
Ten names annnounced for Pacific names after famous racehorses: No. 4475 Flying Fox, Ormonde, Hermit, Minoru, Ladas, Bend 'Or, Persimmon, Robert le Diable, Donovan and Doncaster.

2553 Prince of Wales (formerly Manna) see paragraph Loco. Rly Carr. Wagon Rev., 1927, 33, 32.
Following Prince of Wales' visit to Doncaster Works.

2563 William Whitelaw
William Whitelaw alongside No. 2573 William Whitelaw at Dunfermline in 1929. With Earl of Elgin and Major Stemp.in R.D. Stephen Steam supreme page 115 upper

Illustrations
There are numerous collections of photographs: herein are listed only those books that contain something of real historical value.

Townend, P.N. The colour of steam. V. 4. The LNER Pacifics. Truro: Atlantic, 1985.
This includes colour photograph-based illustrations in post-1945 apple green and in early British Railways liveries: 2582 Sir Hugo at Grantham in summer 1946 (apple green)(C.C.B. Herbert); 60084 Trigo at Newcastle on 20 August 1948 (purple/dark blue) (H.N. James), and 60085 Knight of Thistle at Haymarket in late 1949 (light blue).  

Preserved 4472 Flying Scotsman
Hughes reminds the reader that the locomotive's sometimes adventurous period in preservation is now greater than its period in "service". Inspection of the bibliography in this publication immediately shows that the "preservation period" is inadequately covered in Steamindex. More about this famous locomotive can be found above. The miniature landscape book by McIntosh is excellent on the preservation adventures..

Atkins, Philip. Flying Scotsman: LNER classes A1/A3 Pacific No. 4472, 1923 onwards: am insight jnto maintaining, operating and restoring the legendary steam lcomotive, Sparkford: Haynes Publishing/National Railway Museum, 2016. 172 pp.
Once one has rid oneself of the preconception that the great locomotive is treated within the same bibliographical framework as a Ford Cortina then one can appreciate that it fits this much restored artefact extremely well and is a worthy complement to a personal memory of the BR blue locomotive syncopating its happy way towards Woodhead as viewed from Crowden (having cycled there from Saddleworth).
FLYING Scotsman. J. Stephenson Loco. Soc., 1963, 39, 154-5.
Chronology of No. 4472.
"FLYING" Scotsman saved. Rly Mag., 1963, 109. 78.
Purchase by Mr. Pegler.
Forsythe, H.G. Most famous of them all. Rly Wld, 1959, 20, 152-5. 5 illus.
No.4472 Flying Scotsman
Hughes, Geoffrey. Flying Scotsman: the people's engine. [York]: Friends of the National Railway Museum Enterprises, 2005. 64pp.
A reproduction of Cuneo's superb painting of the preserved locomotive crossing the Forth Bridge on the cover sets the standard for a beautifully written text which is accompanied by many interesting photographs, the majority of which show the locomotive in its preserved state. The author is indeed fortunate to have seen Gresley Pacifics in their prime when he watched them pass Hadley Wood in the 1930s and even has dim memories of seeing Flying Scotsman at the Wembley British Empire Exhibition.
McIntosh, David.
The Flying Scotsman. Hersham: Ian Allan, 2010. 127pp.
Landscape format (pocketbook size): covers the long and adventurous period in "preservation", but also notes its brief existences as Nos. 103, E103 and 60103 (Eric Oldham picture of No. 60103 backing onto afternoon train for Marylebone at Manchester London Road is especially evocative for KPJ as he saw the blue Flying Scotsman syncopating its way towards Woodhead at Crowden level crossing on this train in the 1950s).
MR. Pegier's Pacific. Rly Wld, 1964, 25, (284 January) Supplement. 8 p. 13 illus.
No. 4472 history.
Nicholson, Peter. Flying Scotsman: the world's most travelled steam locomotive. Shepperton: Ian Allan, 1999. 112pp.
Mainly its long career as a preserved locomotive initially in the ownership of Alan Pegler, and later Tony Marchington. Also includes its role in the early talking film (with soundrack) entitled The Flying Scotsman produced by British International Pictures, directed by Cattleton Knight. Includes the very staged "non-stop" run on 1 May 1968 from King's Cross to Edinburgh. Its trips to North America and Australia are also reported. Bill (Sir William) McAlpine engineered the return of the locomotive from California in early 1973, when Pegler became insolvent. For a long time the locomotive was associated with Steamtown at Carnforth. For a time the locomotive was associated with Pete Waterman's Waterman Railways.
Roden, Andrew. Flying Scotsman: an extraordinary story of the world's most famous train. London: Arum, 2007. 246pp. + 8 col. plates (33 illus., some col.). Bibliog.
The sub-title must damn it in many eyes as it is the story of the locomotive not the train. The first eighty pages cover its glorious early history, the remainder cover its its geriatric state when, like its human counterparts, it took to travel (to Australia and to North America) and then beame a problem. Pete Waterman's comments as recorded by Roden say much: "I must say that LNER locomotives don't do a lot for me. I'm a Great Western and LNWR enthusiast, and I wouldn't normally go out of my way to see the A3 working, but on that occasion I thought I'd pop up to Bury because of my contacts with Bill. The old girl was in a hell of a state mechanically, but the one thing I couldn't get over was the adulation – people were even buying lumps of coal off her!"
Sharpe, Brian. The Flying Scotsman: the legend lives on. Barnsley: Wharncliffe Transport, 2009. 192pp.
More media event than book, and might be suitable for turning into a website. Large number of colour illustrations. Originally published 2005. Includes interesting picture of No. 4472 with later type of tender at Marshmoor in January 1939 with snow on ground; also No. 60072 Sunstar at York in 1949 in dark blue livery. Includes both Australian and North American trips and the colourfyul characters who owned the locomotive.
Wheeler, Geoffrey. Fired by steam. London: John Murray, 1987.
Includes coloured plate, based on water colour side elevations of 4472 Flying Scotsman with corridor tender, but without banjo dome: artwork prepared for Sir William McAlpine.

A4 class: 1935

Introduced 1935: The A4 design was based on the earlier A3 class, but the boiler pressure was increased to 250 lb/in2 and the steam passages were redesigned to ensure maximum flow. Externally this class differed considerably, as it was streamlined for hauling the high speed Silver Jubilee train, which was introduced concurrently. During the press debut on September 27th 1935, a speed of 112½ mile/h was attained. Most of the contemporary descriptions refer to this high speed run, the streamlined train-set and the locomotive, but the last sometimes receives least attention. Later No. 4468 Mallard raised the speed ceiling to 126 mile/h, a world record for steam traction. The recent contribution from the late Dennis Carling on the record-breaking run by Mallard is especially interesting. Rutherford's NRM booklet about Mallard is also noteworthy.. For removal of valences see Thompson & his deeds.

Allen, C.J. "The Coronation" and other famous L.N.E.R.trains.
Allen, C.J The Silver Jubilee Express, L.N.E.R.: Britain's first streamlined train and its world's record run. Rly Mag., 1935, 77, 352-62. 6 illus., 2 diagrs. (incl. s. el.), plan, table.
Concentrates attention on the record run.
Bulleid, O.V.S. The "Silver Jubilee" trains, London and North Eastern Railway. Bull. int. Rly Congr. Ass., 1935, 17, 1299-1325 + 2 folding plates. 17 illus., 7 diagrs., 2 plans, 3 tables.
The most detailed account.
"CORONATION" train on the London and North Eastern Railway. Engineering, 1937, 144, 40-2. 3 illus., diagr.. plan.
4-6-2 type streamline locomotive "Silver Link", L.N.E.R. Engineering, 1935, 140, 334-5. diagr. (s. & f. els.)
L.N.E.R. Shunting locomotives in unusual livery. Rly Mag., 1936, 78, 235. illus.
A Doncaster Works shunter was painted in various shades of aluminium paint to determine the shade for Silver Link.
L. and N.E.R. — "The Silver Jubilee" train. Engineer, 1935,160, 318-20. illus., diagr. (s. & f. els.), 2 tables.
NEW "Coronation" trains: L. & N.E. Railway. Loco. Rly Carr. Wagon Rev., 1937, 43, 203-8. 6 illus., diagr. (s. el.)
NEW streamlined locomotive and train, L.N.E.R. Rly Gaz., 1935, 63. 450-8; 460-1.15 illus., 3 diagrs. (incl. s. el.), plan, 2 tables.
A4 and the Silver Jubilee train.
The SILVER Jubilee streamlined train, L.N.E.R. inaugural ceremonies— world record on trial run—beginning of public service. Rly Gaz., 1935, 63, 544-8. 3 illus., map, table.
The "SILVER JUBILEE" train of the L.N.E.R. record trial run. Loco. Rly Carr. Wagon Rev., 1935, 41, 304-8. + plate 2 illus., table, diagr. (s. & f. els.),
Includes a technical description of the A4 design.
TEST runs of "Coronation" trains. Engineer, 1937, 164, 39-41. 4 illus., 4 tables, diagr. (s. & f. els.)

Testing and performance
C.J. Allen stated that every trip in one of the A4-hauled, streamlined trains was a special occasion and this is reflected in the many references to general performance, in terms of reliability, coal consumption etc. Further, no other class of British steam locomotive has been deliberately driven at high speed for record making purposes on so many occasiosn or at such high speeds.

Record breaking journeys.

27 September 1935 : Silver Jubilee press trip :
This run which produced a maximum speed of 112½ mile/h, is described in many of the references noted in the opening section.

Allen, C.J. 113 m.p.h. on the Silver Jubilee : a new London & North Eastern Railway record. Rly Mag., 1936, 79, 245-6. diagr., table.
Dow, George. British steam horses. London: Phoenix, 1950.
pp 110 et seq paint a vivid picture of the experimental high speed runs and the inaugural press run of the Silver Jubilee on which Dow travelled.
A new British rail speed record. Loco. Mag..., 136, 42, 280.
Achieved 113 mile/h at Essendine with No. 2512 Silver Fox
Taylor, Arthur. A personal account of 'The Silver Jubilee' trial run in Hughes, Geoffrey. A Gresley anthology. Didcot: Wild Swan/Gresley Society, 1994. page 76
Driver Taylor was on the footplate when Silver Link attained 112 mile/h, and he was informed of this when Gresley came through the corridor tender onto the footplate. He claimed to be unaware that he was travelling so fast and considered that this was due to the stronger bogie springs than on his egular engine 4476 Royal Lancer.

27 August 1936:113 mile/h on a regular journey on the up Silver Jubilee service.

ANOTHER British speed record. Rly Gaz., 1936, 65, 381. diagr.

L.N.E.R. "Silver Jubilee" train. Locomotive Mag., 1936, 42, 217
This train completed 100,000 miles on 2 July when it passed Hitchin on its northbound journey. Of this mileage 18,283 has been at the rate of over 80 miles per hour, and no time whatever has been booked against any of the locomotives employed.

30 June 1937 : 109½ mile/h—Coronation press trip.
See also references to the Coronation train in the opening section.
Allen, C.J. The new L.M.S. and L.N.E. speed records : trial runs of the Coronation
Scot and Coronation. Rly Mag., 1937, 81, 110-16 +. 2 illus., 2 diagrs.. 6 tables.

3 July 1938 :126 mile/h:
the world record for steam (see also Harris  retrospective section) with Mallard and contribution by eye-witness Le Clair.
L.N.E.R. Train's 125 M.P.H. A British Record. The Times, 1938; Monday, 4 July, page. 14 (Issue 48037).
Driver, fireman and locomtive inspector all named
Allen, C.J. Two miles a minute: the new L.N.E.R. record of 125 m.p.h. Rly Mag., 1938, 83, 79-81. illus., diagr., table.
Bannister, Eric. Trained by Sir Nigel Gresley. 1984.
Present on the high speed run
A NEW L.N.E.R. speed record. Rly Gaz., 1938, 69, 78.9. diagr., table.
Carling, Dennis. Mallard's record: I was there.
Steam Wld, 2008 (253) 52-4.
Editor claimed this posthumous contribution as an "exclusive". On 3 July 1938 Carling was a Test Inspector at Darlington and was in the dynamometer car when No. 4468 Mallard achieved 125 mile/h. Gresley was not on the train, but was represented by D.R. Edge. Norman Newsome was also present to monitor the braking performance: see also Carling's contribution as Chapter 8 in Peter Townend's LNER Pacifics remembered
Remnant, P.T.W. Forty years on. Rly Mag., 1978, 124, 322-5
Remnant was assistant to A.G. Brackenbury of Westinghouse Brake & Signal Co. and was involved in improving the action of the vacuum brake on the LNER high speed trains. This recounts tests behind No. 2510 Quicksilver hauling 16 articulated coaches braking from high speeds: these were followed by the famous run behind Mallard on 3 July 1938

7 September 1948: Non-stop journey of 408½ miles:
Flood damage between Edinburgh and Berwick necessitated that the "non-stop" "Flying Scotsman" be diverted via Galashiels and Tweedsmouth. Normally stops were required, on the diversion, for banking assistance and water, but on one occasion Driver Swan decided to scorn these and make a genuine non-stop journey. This showed that the locomotives were very economical in fuel and water consumption. Others followed and this has led to more controversy and extra-information in 21st century

[Allen, C.J.] Quicksilver, pseud. The "Flying Scotsman": a new British record. Trains ill., 1949, 2, 6-7.
Craig,  J.M. The driver's story: Charlie Peachey in Hughes, Geoffrey. A Gresley anthology. Didcot: Wild Swan/Gresley Society, 1994. pp. 71-6.
Joined the GNR in 1895 and was a driver for 33 years until retirement in 1942. Began with suburban trains at King's Cross. Describes how he coped with route learning. Drove the non-stop Flying Scotsman and states how the crew were served with lunch in the dining car, and had a night out in Edinburgh  as they had earned two and a half days pay. Anecdote about how Will Fyffe talked himself into being taken onto the footplate. Another describes how the crew missed the nothbound train to take them "on the cushions" to Edinburgh and had to travel on a Newcastle train and then had the good fortune to catch a return Whitley Bay to Edinburgh excursion at Newcastle. Worked on both Coronation and Silver Jubilee, and on the latter achieved 104 mile/h at one point. Only one stink bomb was set off by his activities. Described a trip on 2001 Cock o' the North with Gresley on the footplate: immense power but huge coal consumption. Recounts how King Olaf of Norway travelled on the footplate. His house in North Finchley was called Fairway after the locomotive.
McKillop, N. Enginemen elite. 1958.
Farr, Keith:  Legend of the Non-Stop - Part two. Backtrack, 17, 306-13.
Part 1 began on page 275. The service was restored on 31 May 1948 with a timing of 7h 50 min. The line between Edinburgh and Berwick was breached on 12 August. The northbound service took 16 hours on that day, which put it in the Virgin class. Initially the southbound route was via Beattock, Carlisle and Leeds, but we were the first south-bound "non-stop" over the Waverley route to Carlisle and some of the progress was very slow.. The St Boswells to Tweedsmouth route was reopened on 23 August, but Lucker troughs were now 92 miles from Edinburgh, but on 24 August Bill Stevenson with 60029 Woodcock managed to lift the train to Falahill without a banker and start the non-stop run to King's Cross of 408.6 miles - a world record, repeated subsequently in both directions on each of eight occasions. See letter by A.J. Mullay (p. 474) which adds another long way round non-stop, additional info by Farr.

112 mile/h on Stephenson Locomotive Society special on 23 May 1959
See also Transacord recording Triumph of an A4 Pacific

Norman Harvey. A Post-war speed record. Locomotive Causerie No. 209. Rly Wld, 1955, 20, 422-30.
Saturdaay 23 May 1959 No. 60007 Sir Nigel Gresley attained 112 mile/h at Essendine on Stephenson Locomotive Society Golden Jubilee special with Driver Bill Hoole in command, Down run to Newcastle also described.

General performance on the high speed trains.

CORONATION reliability. Rly Mag., 1939, 85, 152.
Lubrication of the Silver Jubilee.  Loco. Rly Carr. Wagon Rev., 1937, 43, 336
Silver Jubilee train of the LNER had been running for over two years, during which period it had run over 260,000 miles. This express covered 2,680 miles a week at an average speed between King's Cross and Darlington of 71.65 m.p.h., and between King's Cross and Newcastle of 67.08 m.p.h., the maximum speed being limited to 90 m.p.h. During the whole period there have been only two cases of hot axleboxes on the engines working the train. The axle boxes of the engines working these expresses are lubricated by Wakefield Silver Jubilee engine oil, and Wakefield mechanical lubricators supply oil to the axleboxes, valves and cylinders.
The SILVER Jubilee, L.N.E.R. Rly Gaz., 1936, 65, 539.
First year of service surveyed.
The SILVER Jubilee in service. Rly Gaz., 1935, 63, 606-7. table.
A Darlington to King's Cross run.
The SILVER Jubilee, L.N.E.R.: some details of current locomotive performance on this high-speed service. Rly Gaz., 1936, 64, 1130-2. diagr., table.
SILVER Jubilee success. Rly Mag., 1938, 82, 62-3.
Includes coal consumption statistics: 37.6 lb/mile. Also notes on patronage..
The SILVER Jubilee's birthday. Rly Mag., 1936, 79, 374.
STREAMLINE reliability. Rly Gaz., 1939, 70, 927.
Notes on the continuous use of No. 4497 Golden Plover on the Coronation train for eight weeks.
STREAMLINE success. Rly Gaz., 1937, 67. 1007.
Mechanical and financial success of the "Silver Jubilee" service.
TWO years results with the Silver Jubilee. Rly Gaz., 1937, 67, 1036.
1948: Inter-regional trials:
Although several failures of bearings occurred, the A4 class returned the lowest fuel and water consumption figures of any locomotive tested in 1948.

Allen, C.J.. The locomotive exchanges, 1870-1948. [1950].

Retrospective and critical :
Gresley's papers and his comments in discussion are especially noteworthy. E. Windle's and B. Spencer's notes on the development of the streamlining are also highly significant.

Allen, C.J. British Pacific locomotives. 1962.
Allen, C.J. The Gresley Pacifics of the LN.E.R. 1950.
Certain diagrams (e.g. cab layouts) and illustrations from this work are not repeated in the later British Pacific locomotives (above).
Allen, C.J. World record-holder for speed with steam. Rly Wld, 25: Mallard: a "Railway World" and the Museum of British Transport Supplement. viii pp. (centre pages of April Issue)
An appreciation of the class published to mark Mallard's installation at the Museum of Transport, Clapham. Includes other LNER Pacific records and dynamometer and detailed log of 3 July 1938 record run driven by J. Duddington and fired by T.H. Bray. Illustrations include:.
No. 60022 near end of service (photograph Eric Oldham)
No. 4468 with dynamometer car and part of Coronation set on test run (painting by V.K. Welch)

Atkins, Philip. Locos from scratch. Rly Mag., 1989, 135, 516-17.
Locomotives built within a limited time scale: The design and construction of the A4 Pacifics was completed within six months at Doncaster Works: chronolgy: boiler ordered 11 March, major steel castings 22 March; cylinder drawings approved 17 April; patterns completed mid-May; cat 6-7 June; main frames laid 26 June; locomotive steamed 7 September...
Atkins, Philip. Odious comparisons. Steam Wld, 2015, (335), 8-14
Annual mileage: 280 miles per day during 1950-8
Aylard, John, Knox, Tommy and Percival, David. What's on the 'Lizzie'? Knebworth: Lineside Twentyfive, 2010. 24pp.
Performance of the non-stop Elizabethan from its introduction in 1953 until its cessation in 1961 (includes Saturday and Sunday associated workings when train was not non-stop)
Bond, Roland C. A lifetime with locomotives. pp. 119-20
Gresley asked Bond to travel on an A4 from London to Newcastle and back: Bond was very impressed by the continuous high speed, but noted severe rolling on the down journeey near Grantham and on the up near Hitchin so Bond suggested using the Swindon bogie
Bond, R.C. Organisation and control of locomotive repairs on British Railways. J. Instn Loco. Engrs, 1953, 43, 175-265. (Paper No. 520).
Annual mileage figures for the class are quoted.
Bannister, Eric.  'Green Arrow'  — the versatile 'V2'. Rly Wld, 1981, 44, 576
Re Meacher's comments regarding the vee-shaped front cab windows of the 'V2s'. Writer was present in Doncaster Works drawing office when the cab used for the 'A4s' was designed by E. Windle and T. Street (the Chief Draughtsman). Its shape had nothing to do with streamlining. The 'A3s' were fitted with hinged screens in front of the driver's window which were altered by me to drop into a slot so that the screen was at a 45° angle. The reason for these screens was that if an engine's tender overfilled when picking up from the water troughs, the water broke the front cab window. I was present on the footplate when it happened on one occasion, having been sent out to investigate by the Doncaster Chief Draughtsman. The vee-front to the cab of the 'A4s' was the result of my report and cured the problem; the design was perpetuated on the 'V2s' for the same reason.
Brown, W. Rhind. The magic of a name. North British Railway Study Gp J., 2010, 110, 34-5.
Author wonders if the name Silver Link (A4 No. 2509) from Sir Walter Scott.'s Lay of the Last Minstrel was a memorial to Gresley's wife.
Bulleid, O.V.S. Locomotives I have known. Proc. Instn mech. Engrs, 1945, 152, 341-52 + 6 plates. 18 illus., 12 diagrs., 11 tables.
Commented on the development of the design noting the improved boiler and the streamlining.
Bulleid, O.V.S. discussion on Spencer, B. The development of L.N.E.R. locomotive design, 1923-1941.  J. Instn Loco. Engrs, 1947, 37, 211-12. (Paper No. 465)
There was one small point with regard to streamlining which might be of interest. Not only were the models tested in the wind tunnel, but Sir Nigel, who knew Bugatti, followed his work in France with close interest, made it his business to travel on the Bugatti rail-cars between Deauville and Paris, and was much impressed by the efficiency with which the wedge form of the front of the engine passed through the atmosphere with the minimum of disturbance. It was really that which led to the type of front end adopted on the "Pacifics."
Cameron, K.R.M. Chapter 10 in Peter Townend. LNER Pacifics remembered.
Steamed well provided ashpan shelves kept clean; dfid not like firedoor. On Scottish Region Glasgow to Aberdeen services Aberdeen and Perth crews took to them but Balornock crews prefered BR Caprotti class 5s at first.
Cameron, K.R.M. via Rogers, H.C.B. Thompson & Peppercorn. 1979. p. 52 and 150
Whilst Assistant DPMS at King's Cross Cameron found that they were either brilliant or awful: they were like racehorses in that they demanded attention to get the best results. Although an LMS man he could see little difference between the Duchess class and the A4 class..
Clay, J.F. How great are those A4s? J. Stephenson Loco. Soc., 1960, 36, 114-18. illus.
Objective review of performance.
Clay, John F. Locomotive working with the Streamliners. in  Hughes, Geoffrey. A Gresley anthology. Didcot: Wild Swan/Gresley Society, 1994. pp. 11-18.
Timekeeping, especially by the Silver Jubilee was excellent. The Coronation was a more difficult task: the train was heavier and the demand for electricity was higher. On some southbound journeys the locomotives ran out of fuel. Author wonders why Kylchap double chimney locomotives were not allocated to this service. The down West Riding Limited was more difficult to schedule.
Cook, A.F. Raising steam on the LMS: the evolution of LMS locomotive boilers. Huntingdon: RCTS, 1999. 233pp.
Table 50 (page 217) quotes the cost of classified boiler repairs on a comparitive basis in pence per mile in 1954: 2.7 pence/mile for a Duchess as against 0.8 for an A4 and 0.6 for a Merchant Navy..
Cook, K.J. The steam locomotive: a machine of precision. J. Instn Loco. Engrs., 1955, 45, 418.
Fitting of Churchward type big ends to Gresley Pacifics
Coster, P.J. Chapter 16 in Peter Townend. LNER Pacifics remembered.
Lineside observations of Post-war non-stop workings from London to Edinburgh
Ellis, C.H. Some classic locomotives. 1949.
A delightfully off-beat account of the Silver Jubilee press run is given on page 119: "One night in 1935 I was on one of the platforms of King's Cross, having just got out of the Silver Jubilee streamlined train after its breathless press run. It was an excited crowd on that platform; we had been travelling faster than ever before in a steam train, during that afternoon; humming along at well over a hundred miles an hour for many miles at, a stretch had become almost a familiar sensation. Passengers and spectators were surging round Gresley's Silver Link, which to unused eyes looked faintly like a small airship under the dim station roof, and her designer, looking very large and benevolent, was up on the footplate with the enginemen while cameramen let off flashlights in their faces."
Evans, M.  Pacific steam : the British Pacific locomotive. 1961.
Farr, K.S. 'A4' golden jubilee.. Rly Mag., 1985, 131, 397-9.
Mentions the 102 mile/h attained by No. 60007 Sir Nigel Gresley at Little Bytham in July 1963.
Farr, K.S. 'Mallard' memories. Rly Mag., 1988, 134, 462-3.
A somewhat jaundiced view of the A4 speed records. Notes that Edward Thompson was on the footplate on 27 August 1936 when 2512 Silver Fox hauling the Silver Jubilee attempted a fast run down from Stoke Summit and damaged its middle big end. The writer takes a somewhat jaundiced view of the LNER high speed runs and questions whether the Civil Engineer was kept fully informed.
Gresley, H.N. Development of high-speed running on railways. Greenock, Greenock Philosophical Society, 1937. 24 p. table. (Papers of the Greenock Philosophical Society—Watt Anniversary Lecture).
A review of world development is followed by a description of the A4 class. The topic of streamlining is accentuated.
Gresley, H.N. [Presidential address]. Proc. Instn mech. Engrs, 1936, 133, 251-65.3 tables.
A description of the high-speed trains, including the development of streamlining, plus results of the Silver Jubilee in service.
Gresley, H.N. Discussion on McDermid, W.F. Brakes for streamlined railway vehicles. J. Instn Loco. Engrs, 1935, 25, 309-68. (Paper No. 337).
Streamlined implies fast rather than a physical type of vehicle.
Harris, Michael. No. 4468, Mallard: fastest of them all. Rly Wld, 1986, 47, 646-50.
Short account of the record breaking run, including the reaction by Inspector Sam Jenkins to the detection of the odour from the stink bomb to indicate that a bearing was overheating and to inform Driver Duddington to slow down, plus an account of the further life of the locomotive until withdrawn for preservation. Harris had the assistance of John Bellwood in writing this feature and Bellwood argued that the Kylchap chimney gave the locomotive considerable edge both in terms of power and Peter Townend argued that locomotives so-fitted were easier to maintain as the greater draught kept the tubes cleaner.
Harrison, J.F. The gathering of the new crop. (Presidential Address)  J. Instn Loco. Engrs., 336-56. + plate. 16 illus. 4 diagrs.
Includes an appreciation of the Gresley Pacifics.
Holyhead, G.C. The "big green yins". Rly Wld, 1963, 24, 218-19. illus.
The class ended its service on light, high-speed trains between Glasgow and Aberdeen. The enginemen's impressions of this design are recorded in this article, hence the Glaswegian expression "big green yins".
Joyce, Michael. The badger's back. in Hughes, Geoffrey. A Gresley anthology. Didcot: Wild Swan/Gresley Society, 1994. pp. 83-5.
Account of an unofficial footplate ride, via the corridor tender, on 60028 with Driver Charlie Price when the ride was "as rough as a badger's back".
Joyce, Michael.  'The Silver Jubilee' — a day to remember in  Hughes, Geoffrey. A Gresley anthology. Didcot: Wild Swan/Gresley Society, 1994. pp. 19-20.
Account of journey by 15 years old office boy on up Silver Jubilee from Darlington in 1936.
LeClair, L.J. discussion on: Newsome, N. The development of L.N.E.R. carriage and wagon design, 1923-1941. J. Instn Loco. Engrs, 1948, 38, page 473
Observations on the 126 mile/h test run.
Livesay, E.H.
London to Edinburgh on the footplate. Loco. Rly Carr. Wagon Rev., 1938, 44, 337-8.
Written as a companion article to the same author's "Vancouver to Calgary on the footplate" (Loco. Rly Carr. Wagon Rev., 1938, 44, 244-8).
Livesay, E.H.
Scottish locomotive experiences. No. 7 — L.N.E.R. Edinburgh-Newcastle trains, "A4" engines. Engineer, 1939, 168, 438-40. 2 illus., 2 diagrs.
Lowther, David. The anonymous years in Hughes, Geoffrey. A Gresley anthology. Didcot: Wild Swan/Gresley Society, 1994. pp. 21-4.
Not really relevant as relates to the coaching stock for the streamlined trains post-WW2: rumours of reintroduction of the Silver Jubilee were unfounded. The stock was used, but the restaurant cars were wihdrawn when cooking by electricity was abandoned. The Fife Coast Express was the sole train to exploit the stock. The FO 5.37 Manchester Exchange to Newcastle in August 1962 was one of the final workings. The illus. of 60047 Donovan hauling the Silver Jubilee triplutet restaurant car was cropped such that the relevant cars were lost.
McKillop, N. The Gresley touch. Trains Ann., 1956, 5-10. 2 illus.
McKillop drove Mallard north from Newcastle for an exhibition in Dundee. He describes this high speed journey during which the Flamman speed recorder indicated 107 mile/h at one point.
McNair, A.H. discussion on Peacock, D.W. Railway wind tunnel work. J. Instn Loco. Engrs., 1951, 41, 634: (Paper No. 506)
In connection with smoke deflection the Author remarked that the L.N.E. type of front end which was used on the A4 class engines was found to be less satisfactory than the L.M.S. type, but he understood that Sir Nigel Gresley, when he designed the front end, did not have streamlining entirely in mind, but had also smoke deflection. A considerable amount of work put into this particular point resulted ultimately in the wedge shaped front end being extended comparatively far back on the boiler barrel. At the same time the chimney casing was kept completely proud of the ultimate top of the casing which allowed a wedge of air, when the wind was at an angle to the train, to be driven in between the point of exhaust and the top of the casing behind the chimney.
Mayes, Frank. Did 'Number 9' ever reach 120 miles an hour? Steam Wld, 1990 (34) 7-11.
On an up working of the non-stop Capitals Limited hauled by 60009 Union of South Africa the locomotive had a faulty water pick-up scoop and a halt had to be made for water at Babworth. Driver Alf Smith attempted to make up the lost time by running very rapidly doen the bank from Stoke Summit and estimated that they reached 120 mile/h: the pen had been lifted off the flaman recorder by Inspector John Cunningham who was travelling on the locomotive on this day.
Mayes, F.
Firing the A4 Pacifics. Rly Wld, 1964, 25, 3-6+ 4. illus., table.
Experiences in the King's Cross "top link".
Miller, N.G. Coasting at 25% cut-off. J. Stephenson Loco. Soc., 1956, 32, 138-9.
Reason for not coasting at the more usual 15%.
Mullay, A.J. Non-stop! : London to Scotland steam. Gloucester : Sutton, 1989. 120 pp.
Mullay, A.J. Streamlined steam: Britain's 1930s luxury expresses. Newton Abbot : David & Charles, 1994. 128 pp.
Neve, Eric. The 'Coronation' of the LNER. Rly Wld, 1987, 48, 390-3
Mentions original concept of Aberdeen in nine hours, but settled on Edinburgh, originally with a York stop.Includes logs of runs with York stop behind No. 4491 Commonwealth of Australia:
Neve, Eric. The last LNER luxury expresses – the 'West Riding Limited' and the 'East Anglian'. Rly Wld, 1987, 48, 614-17.
Includes logs of runs: the West Riding Limited was aimed at giving the Yorkshire businessman from Leeds and Bradford time for a full afternoon in London and enough time in the office before a rapid transit to London: the LNER obviously hoped to lunch and dine its customers en route.
Neve, Eric. Memories of the Gresley Streamliners in  Hughes, Geoffrey. A Gresley anthology. Didcot: Wild Swan/Gresley Society, 1994. pp. 1-9.
Captures the excitement of seeing the 2509 Silver Link departing King's Cross on the 7.10 am to Cambridge on 14 September 1935, and on several other mundane journeys before  the arrival of the return trial run with the Silver Jubilee train on 27 September when Gresley exclaimed "112 mile/h" to waiting press men. Describes the performance of all the streamlined trains, such as the rare engine failures where non-streamlined Pacifics and Atlantics attempted to maintain the exacting schedules.
Neve, Eric. The 'Silver Jubilee' of the LNER: Britain's first streamlined train. Rly Wld, 1985, 46, 468-71.
Captures some of initial excitement of 112 mile/h running and reliability of high speed service
Railway Correspondence & Travel Society. Locomotives of the LNER. Part 2A. Tender engines—classes A1 to A10. 1978.
Riemsdijk, J.T. van. The LMS, T.F. Coleman and locomotives. Backtrack, 11, 106-7 (letter)
See also Michael Rutherford's 'Provocations' in Volume 10 page 560 et seq, Only part of this letter is reproduced herein.
A look at the reports of the 1948 locomotive exchanges reminded me that the coal consumption of City of Bradford was held down by ignoring the passing times laid down and running gently uphill while racing down — which predictably brought the greatest benefit on the switchback road between Salisbury and Exeter. In the tabulated information relating to the classes I found area of the double blast nozzle to be 30.96sq in, whereas the A4 had 39.27. This was made the more extraordinary by the fact that the four beats of the LMS locomotive each exhausted two cylinder ends, while the six of the A4 each exhausted rather less (one cylinder end of slightly greater capacity). No wonder that the boiler steamed, but this surely disposes of the often-repeated assertion that a 'Duchess' could have equalled Mallard's speed record if it had had Stoke bank to race upon. ...The A4 has 7.9% clearance and actually, in theory, better valve events, though these might not be maintained at high mileages.
Rimmer, Alan. Testing times at Derby: a 'Privileged' view of steam. Usk: Oakwood, 2004. 120pp. (RS14)
Found all Gresley Paqcifics to be smooth riding compared with Peppercorn A1 class. Mainly Chapter 10..
Rutherford, Michael. Mallard: the record breaker. Newburn House (Friends of the NRM), 1988.
Ottley 18148: although only 48 page pamphlet brings together much hidden elsewhere: excellent illustrations.
Scott, Ron. and Reed, Brian. Gresley A4s. Loco Profile 19..
Notable for its colour centre spread (the work of David Warner) which depicts No. 2509 Silver Link in its as built condition and No. 4468 Mallard in its National Railway Museum condition. The text is notable for its incorporation of a great deal in a few words. Acknowledged assistance from Peter N. Townend, Arthur Wolstenholme, Eric Trask and Kenneth H. Leech.
Shorland-Ball, Rob. 'Mallard' in Neil Cossons Making of the modern world. pp. 170-1.
Deputy Head, NRM. Main colour picture shows cab and locomotive is shown in small black & photograph. Text includes extract from BBC interview with Driver Duddington in April 1944.
Spencer, B. Discussion on: Holcroft, H. Smoke deflectors for locomotives. J. Instn Loco. Engrs, 1941, 31, p.503-4.
Spencer depicted a diagram of a tentative form of streamlining in which the chimney cowling was projected horizontally back to meet the top of the boiler casing. The locomotives were actually built with a sloping "tail" to the chimney.
Spencer, B. The development of L.N.E.R. locomotive design, 1923-1941.  J. Instn Loco. Engrs, 1947, 37, 222 et seq. (Paper No. 465)
Reply to question from Cox concerning the performance of copper firebox stays on high pressure boilers, the LNER had found that the stay heads in the fireboxes of the Pacific engines carrying a working pressure of 220 psi deteriorated more rapidly than those of the 180 lb. psi boiler and that the area subject to deterioration was extended, but there was no noticeable difference between the performance of the copper firebox stays on the 220 psi boilers and those on the 250 psi boilers. The firebox combustion chamber on the 250 lb. boilers was 12 in. longer than on the 220 lb. and 180 lb. boilers and would possibly have some bearing on the matter. The average mileages obtained with the 220 psi and 250 psi boilers on the Pacifics between boiler lifts was 70,000 to 80,000 miles.
Stokes, Ken. Both sides of the footplate. Truro: Bradford Barton, [1985?]. Chap. 10.
This Midland-trained footplate man found the ultimate steam motive power on the East Coast Mainline where the Pacifics rode perfectly, the water pick-up gear operated to perfection (and water troughs were clearly marked) and where full regulator and short cut-off working was the norm. He even found that the sheet which connected the cab to the tender was significant: in the absence of one the exhaust entered the cab and made driving difficult. On his final trip 107 mile/h was attained at the usual location descending from Stoke Summit towards the Fens.
Topham, W.L. The running man's ideal locomotive. J. Instn Loco. Engrs., 1946, 36, 3-29. Disc.: 29-91. (Paper No. 456)
Admired the cabside windscreens fitted to the A4 class
Topping, Brian. The record breakers... Steam Wld, 2008 (253) 44-50.
Anniversary of No. 4468 Mallard's record breaking run of 3 July 1938: includes a reproduction of the graph which recorded the speed and the gradient. A detailed account which notes that Gresley was not present on the train. Also makes reference to the LMS speed record involving No. 6220 Coronation and its alleged speed of 114 mile/h based on the speedometer on the locomotive as against 112.5 mile/h via several stop-watches. Riddles was on the footplate of Coronation which approached Crewe platform at an excessive speed. Topping notes that Edge represented Gresley on the Mallard run which was nominally in connection with testing a Westinghouse quick release vacuum brake mechanism. Norman Newsome (incorrectly quoted as Newson) and Reg Stubley's observations on Gresley are noted in the introduction. Topping also notes that other than the footplate crew (Driver Joe Duddington and fireman Tommy Bray) Inspector  (Sam) Jenkins was also present: the well known photograph of the trio on arrival at Peterborough is reproduced.
Townend, P.N. East Coast Pacifics at work. 1982.
Train, J.C.L. discussion on Cox, E.S. Balancing of locomotive reciprocating parts. J. Instn Loco. Engrs., 1943, 33, 221-2. (Paper No. 432)
Commented at length on his concern about the effect of high speed trains, but had accepted Gresley's reassurances. He considered that the steam locomotive was at a disadvantage compared with other forms of motive power due to their reciprocating parts
Trask E.D. The smokebox of streamlined engines. Rly Gaz., 1940, 72, 220-2. 2 illus., 2 diagrs.
Reprinted from the London & North Eastern Railway Magazine, 1939.
Turner, T. Henry discussion on Wise, S. and E S Burdon. The dual roles of design and surface treatment in combating fatigue failures. J. Instn Loco. Engrs., 1964, 54. 187-9. (Paper No. 655)
It has long been known that the front axle of the tender of a steam locomotive suffered excessively from corrosion fatigue because of the fireman’s slaking of his coal with water that dripped on to the axle. Thirty years ago he had to investigate the corrosion fatigue fractures of the driving wheels of the Pacifics that became the fastest steam locomotives in the world. Flexing of the wheel rim between the spokes was made apparent when at the request of Sir Nigel Gresley, Professor Coker carried out some tests with his novel photo-elastic apparatus, using plastic models of the driving wheels. Knifing to gauge produced a dead sharp right angle inner corner of the tyre that was in tension between the spokes and water could penetrate between tyre and wheel. The chip-crack-freeness of the inner machined surface of the tyre was obviously desirable, where the tyre touched the wheel and was stressed in tension, by shrinking and by bending in service.
Turner, T. Henry discussion on Robson, A.E. Railcar development on British Railways. J. Instn Loco. Engrs., 1962, 52, 113-14. (Paper No. 632)
Stated that the front end of the railcar should have a slope backwards at the top. "It should be recalled that when two steam locomotives passed one another at high speed there was nothing like the usual shock to the passengers or to the driver when the engines were Gresley streamlined “Pacifics”. If higher speed running was to be operated blunt-ended trains would not be good. The Gresley design was derived from Sir Nigel’s noting the chisel-shaped ends of the early French Renault railcars. Instead of hitting the passing train an alarming bump the air, displaced by the train, was deflected upwards. The newer Midland Pullman had a handsome if somewhat less effective slope back".
Webber, A.F. The proportions of locomotive boilers. J. Instn Loco. Engrs, 1937, 27, 688-726. (Paper 378).
An analysis of A4 on a comparative basis.
Webster, H.C. Early days with the class "A4" Pacifics: the personal experiences of an LN.E.R. locomotive man in the late 1930's. Trains Ann., 1963, 5-12+. 8 illus.
The author notes some of the difficulties experienced in maintaining the exacting high speed schedules, especially that of the Coronation, and in the maintenance of locomotives equipped with streamlined casings. One anecdote concerns one of the Commonwealth High Commissioners invited onto the cab following the unveiling of a plaque on the cabside failing to open the regulator then yanking it open too far which led to violent slipping: the High Commissioner remained calm and quickly closed the regulator. Notes the hot air trap caused by the rubber sheeting placed between cab and tender..
Wheeler, Geoffrey. Fired by steam. London: John Murray, 1987.
Includes coloured plate, based on water colour side elevations of No. 4468 Mallard as it ran on ran on record-breaking day: that is without plaques.
Wilson, G.R.S. Report on the derailment which occurred on 1st September, 1955 at Westwood Junction near Peterborough in the Eastern Region, British Railways. Ministry of Transport & Civil Aviation: Railway accidents [monograph]. London, H.M.S.O., 1956. 10 p. + 6 plates (incl. 1 folding). 5 illus., diagr. (s. & f. els), 2 plans.
This accident (to the W1 locomotive) revealed inherent weakness in the design of the bogie side frames and stretcher bars on Gresley's larger locomotives.
Windle, E. Discussion on Holcroft, H. Smoke deflectors for locomotives. J. Instn Loco. Engrs, 1941, 31, Pp. 490-9 (9 illus).
Windle described the smokedeflection and stream lining experiments which led to the A4 Bugatti-type front-end.
Yeadon, Willie B. Yeadon's register of L.N.E.R. locomotives. Vol.2: Gresley A4 and W1 Classes. Irwell Press, 1990.

Names and embellishments:
The original names were those of sea, marsh or moorland birds, e.g. Seagull, Wild Swan, etc. Later, some of these singularfy appropriate names were either no longer pursued or removed in favour of Commonwealth country, railway director or other "personality" names.

A boy's ambition fulfilled: Sir R. Wedgwood's name on an engine. The Times, 4 March 1939. page 9
No. 4469 named Sir Ralph Wedgwood at Marylebone Station on day of his retirement
C.P.R. bell for L.N.E.R. loco. Loco. Rly Carr. Wagon Rev., 1938, 44, 115. illus.
As fitted to No. 4489 Dominion of Canada.
LOCOMOTIVE naming ceremonies at King's Cross. Rly Gaz., 1937, 67, 44.
Dominion of Canada, Empire of India and Union of South Africa.
L.N.E.R. directors honour Sir Nigel Gresley. Loco. Rly Carr. Wagon Rev., 1937, 43, 400. illus.
Naming cermeony of No. 4498 Sir Nigel Gresley with key of who was present.
L.N.E.R. No. 4496 "Dwight D. Eisenhower".  Loco. Rly Carr. Wagon Rev., 1945, 51, 165.
Just the caption: no further information (but A4 in prewar garter blue livery, but without valences)
L.N.E.R. Pacific named "Commonwealth of Australia". Rly Gaz., 1937, 66, 1218.
L.N.E.R. Pacific named "Sir Nigel Gresley" Rly Gaz., 1937, 67, 944; 991-2. 4 illus.
L.N.E.R. Pacific named "Sir Ralph Wedgwood". Rly Gaz., 1939, 70, 440. illus. p. 424.
London & North Eastern Railway. Locomotive Mag., 1936, 42, 10.
No. 2512 Silver Fox fitted with stainless steel fox emblem and other stainless steel decorations
NAMING of streamlined locomotive "Dominon of Canada" at King's Cross Station. Rly Gaz., 1937, 66, 1184. 2 illus. p.1174.
"SIR Nigel Gresley", 4-6-2. Rly Gaz., 1937, 67, 965.
Editorial comment on the naming of No. 4498.

Illustrations
There are numerous collections of photographs: herein are listed only those books that contain something of historical value.

Townend, P.N. The colour of steam. V. 4. The LNER Pacifics. Truro: Atlantic, 1985.
This includes colour photograph based illustrations in both pre-1939 and post-1945 garter blue: 22 Mallard is shown departing Waterloo with the Great Western dynamometer car and Southern Railway stock during the 1948 locomotive exchanges (C.C.B. Herbert); 8 Dwight D. Eisenhower on parcels train at Sandy on 26 August 1948 (H.N. James); 4498 Sir Nigel Gresley at Darlington in August 1938. Also 2509 Silver Link in original silver livery on up Flying Scotsman at Grantham in June 1937.

1922 : The Raven Pacifics (LNER class A2)
These were, by general agreement (see Allen or Smeddle), unsuccessful locomotives. The series constructed in 1924 were equipped with Cartazzi trailing trucks. City names were added at the same time. Finally in 1929, one locomotive was rebuilt with a Gresley Pacific boiler and standard cab.

1924: Cartazzi trailing truck.

NEW Pacific type locomotives, London & North Eastern Ry. (North Division). Loco. Rly Carr. Wagon Rev., 1924, 30, 112. illus.

1929 : Gresley Pacific boiler fitted to No. 2404.

NEW boiler for "Pacific" locomotive, L. & N.E.R. Loco. Rly Carr. Wagon Rev., 1929, 35, 400-1. illus., 2 diagrs. (s. & f. els.), table.
RE-BOILERED 4-6-2 express locomotive, L.N.E.R. Rly Mag., 1930, 66, 94. illus.

Retrospective and critical.

Allen, C.J. British Pacific locomotives. 1962.
See Chapter 2.
Baxter, F.L. Balancing of three-cylinder locomotives. Engineer, 1935, 160, 84-6. 5 diagrs., 8 tables.
The A2 class is considered on a comparative basis.
Cook, A.F. The Raven Pacifics of the North Eastern. Trains ill., 1950, 3, 202-6. 5 illus.
Nock, O.S. The Great Northern Railway. 1958. Chapter 14
Includes results of the tests made between the Al and A2 classes in 1923. At that time there was very little difference in the performance of the two types. 
Railway Correspondence & Travel Society. Locomotives of the LNER. Part 2A. Tender engines—classes A1 to A10. 1978.
Pp. 136-42.
Smeddle, R.A. The North Eastern Railway and recent railway developments. J.Instn
Loco. Engrs
, 1959/60, 605-21. (Presidential Address).

Part of the address criticises the A2 design.
Weight, R.A.H. A short-lived Pacific class. Rly Mag., 1949, 95, 195-6. illus.
Yeadon, Willie B. Yeadon's register of L.N.E.R. locomotives. Vol.3: Raven, Thompson and Peppercorn Pacifics. Irwell Press, 1991.
Young, JA. The Raven Pacifics. Rly Obsr, 1936,8, 245.

4-6-4

W1: 1930: Hush-Hush
This experimental locomotive incorporated a Yarrow high pressure water-tube boiler coupled with a four-cylinder compound engine. The trailing truck arrangement has caused doubt as to the correct Whyte notation for this design and it is sometimes quoted as 4-6-2-2. There is a wealth of published information which is not in character with the soubriquet, "Hush Hush" locomotive. Gresley's "High pressure locomotives" (retrospective section) is the major study of the design. The RCTS History is also extremely thorough. The patents associated with this locomotive are listed on the Gresley page, together with some information about Yarrow..

EXPERIMENTAL high-pressure compound locomotive, L.N.E.R.. Rly Engr, 1930, 51, 54-7. 3 illus., 2 diagrs. (incl. s.el.)
4-6-4 high-pressure watertube boiler locomotive, L.N.E.R. Rly Mag.. 1930, 66, 89-91 + plate f.p. 89. illus.
HIGH-PRESSURE compound "Baltic" type locomotive, L.N.E.R.. Loco. Rly Carr. Wagon Rev., 1930, 36, 1-3. 2 illus., diagr. (s. & f. els.)
HIGH-PRESSURE compound locomotive, London & North Eastern Railway. J. Instn Loco. Engrs, 1930, 20, 134-6. illus.
HIGH-PRESSURE 4-6-2-2-type locomotive on the London and North Eastern Railway. Engineering, 1929, 128, 842; 850. 3 illus., 2 diagrs., (s. & f. els.)

Diagram
London & North Eastern Railway.Diagram of compound locomotive No. 10000. Loco. Rly Carr. Wagon Rev., 1933, 39, 291.
Isometric projection drawing of locomotive and tender by H. Clark showing interior of locomotive: sold by the LNER for one shilling. Also reproduced in F.A.S. Brown Nigel Gresley as folding plate..

Components of the design considered in detail. (see also Yarrow in the retrospective section).

BUILT-UP locomotive crank axle. Engineer, 1930, 149, 160. illus., diagr.
Metcalfe, Richard. Davies & Metcalfe Ltd: railway engineers to the world. 1999
See Chapter 18 which covers the Class HP injectors
The NEW Gresham feed water heater for locomotives. Rly Engr, 1931, 52, 92. diagr.
VALVE gear of L. & N.E. Ry. high-pressure locomotive. Loco. Rly Carr. Wagon Rev., 1931, 37, 113-15. 2 diagrs.
Modified Walschaerts-Gresley gear.

Testing

TESTS on boiler of L.N.E.R. engine No. 10000. Engineering, 1934, 158, 19 1-3. 7 diagrs.

W1: 1937:
The locomotive was rebuilt with a normal Stephenson boiler, three simple expansion cylinders and A4-type streamlining. It emerged from Doncaster Works in November 1937, but Jones (in published form) fails to note any contemporary references.

Allen, C.J. The rebuilt No. 10000, L.N.E.R. Rly Mag., 1938, 82, 36-40. 3 illus., diagr (s. & f. els.).
Includes performance of locomotive on up Flying Scotsman from Darlington to King's Cross, with very fast running between Huntingdon and Stevenage.
Rebuilt engine No. 10,000, L.N.E.R. Locomotive Mag., 1937, 43, 372-3. illustration, diagram (side  & front elevation)
Entry missing from Steam locomotive development (had to wait until 2015)

Retrospective and critical

Allen, C.J. British Pacific locomotives. 1962.
Pp. 37-41 contain a review of the design.
Allen, C.J. Lone locomotives. Trains Ann., 1956. 67-79; 82-4. 25 illus.
An account of several designs which were not duplicated including the W1.
Brown, F.A.S. Nigel Gresley : locomotive engineer. 1961.
Folding diagram at end of book giving cut-away drawing of 10000 in original (water-tube) condition prepared: draing prepared by LNER
Brown, William. Hush-Hush: the story of LNER 10000. Southampton: Kestrel Railway Books, 2010. 122pp
Based on a file which came from Darlington Works and which is stored in the NRM; extremely well illustrated, but there are gaps in coverage, notably on the Yarrow side, although the photographs taken at Yarrow's are extremely good. Photograph on Forth Bridge p. 51; during Perth test at Dunfremline Lower on 23 February 1930 p. 50; at Cambridge on 24 May 1930 (pp. 54 and 55; on Flying Scotsman on pp 58 et seq including with Gresley on artrival at King's Coss on 31 July 1930 p. 59 and returning north on 1 August 1930 at Greenwood on p. 61 and passing York on page 62; at Wavertree (L&MR Centenary) pp. 63-4; at Norwich on 2 May 1931 (pp. 71-2) including with No. 4472 Flying Scotsman; at Hull Dairycoates and at Ripon with counter pressure locomotive (p. 79).
Carling, D.R. in Peter Towned. LNER Pacifics remembered. Chapter 8.
Observed rebuilt locomotive on fast freight in 1937 between King's Cross and Peterborough and considered it had edge over V2
Ellison, J.H. Experimental locomotives. 2. L.N.E.R. high pressure 4-cylinder compound locomotive, No.10,000. Rly Obsr, 1941,13, 177-8. illus.
Gresley, H.N. High pressure locomotives. Proc. Instn mech. Engrs, 1931, 120, 101-35.
Sectionalized diagrams are included.
Gresley, H.N. Discussion at: International Railway Congress Association, 11th Session, Madrid, 1930. 2nd Session. Question 5. Locomotives of new types. Bull. int. Rly Congr. Ass., 1931, 13,103-4.
Comment on water-tube boilers.
Le Fleming, H.M. Gresley's "Hush Hush" experiment: a study of the L.N.E.R.water tube boiler 4-6-4 No. 10000. Trains ill., 1955, 8, 49-52. 3 illus., table.
Jones called this a thorough survey, but this was prior to the RCTS account.
Matthewson-Dick, T. Address by the President. How they run. J. Instn Loco. Engrs, 1967, 57, 155-96.
He had been responsible for the Sentinel railcar Phenomena and this had prepared him for work with No. 10000 in its original form when he was a Technical Inspector at Gateshead to instruct footplate crews. There were problems with the cracking of the inner skin of the boiler wall which drew in cold air. Frequent adjustments had to be made to the cut-off due to leakage of steam from the high pressure to low pressure cylinders via cracks in the high pressure valve liners. The diaphragms valve for tapping the 450 psi to convert it to 250 psi for the auxiliaries was extremely temperamental. The low point was reached when No. 10000 failed at Plessey North of Newcastle when hauling the Flying Scotsman from Edinburgh and had to replaced by a K3 class running tender first to bring the train into Newcastle..
Pargiter, G.M. discussion on Selby, F.W. Compound locomotives. J. Instn Loco. Engrs, 1930, 20, 317-19 (Paper No. 257)
Implied criticism of LNER No. 10000: it has been fitted with almost every device which exists with the exception of wings and a propeller,
Railway Correspondence & Travel Society
Locomotives of the L.N.E.R.. Part 6C. Tender engines – classes Q1 to Y10
. 1984.
An extremely thorough account of the original locomotive and its modifications implemented at Darlington, and it is tempting to consider that K. Hoole was responsible for this information. High power outputs were recorded in the final tests.
Ransome-Wallis, P. Unconventional forms of motive power [in:] Ransome-Wallis, P. editor. The concise encyclopaedia of world railway locomotives. 1959.
Pp.461-77 (Chap. 9) : Includes the original W1 design.
Tufnell, Robert Prototype locomotives. Newton Abbot: David & Charles, 1985. 112pp.
Chapter 5: The first No 10000 in view of mention of K. Hoole in comment on RCTS (above) it is noteworthy that Tufnell acknowledges Hoole in his chapter.
"...in view of the close connection between Darlington and naval boiler practice as used in ships built on the North East coast, the idea of using the Yarrow water tube type of boiler was formulated. It was obviously not appreciated that a water tube boiler when mounted on a rigid base such as a power station or a ship's engine room, with proper facilities for expansion, is very different to the mountings on a lively chassis such as a locomotive"

Tuplin, W.A. The steam locomotive. 1974. Chapter 6. Unconventional steam locomotives.
In other spheres of operation of steam power, increasing use was made, after the start of the twentieth century, of the water-tube boiler and this seemed to be an obvious alternative to the Stephenson boiler in locomotives. For one thing, it had none of the stays that were continually breaking in Stephenson boilers. So water-tube boilers were repeatedly tried in locomotives but could not survive against their inherent disadvantages that: (1) loss of heat through the walls of the furnace was excessive unless they were made so thick that little room was left for the fire-grate; (2) it was impracticable to keep the tubes reasonably free from scale deposited by such waters as could be supplied to locomotives in ordinary service. An advantage of the water-tube boiler is that it may be made to work at much higher steam pressures than are practicable in the conventional locomotive boiler and it therefore offered the possibility of using compound expansion in circumstances that could permit it to show some useful advantage over single-expansion. This was never realised in regular practice....
The origin of the design seems to have been the idea that by using a boiler pressure of 450 lb. per sq. in. compounding could be applied with perceptible advantage in economy of coal, but there seems to have been no recognition of the fact that that result can be achieved only by working at a much higher expansion ratio than is practicable in the conventional locomotive. For the cylinders of No. 10000 offered not the slightest chance of this at any power output commensurate to the size of the locomotive.
The pressure of 450 lb per sq. in. was far beyond the practicable limit for the conventional locomotive boiler and that is why the water-tube boiler was used. Its design was accomplished in conjunction with the Scottish marine-boiler manufacturers Yarrow & Co. It had the feature that the outer casing was a double wall and that the air fed to the ashpan reached it by passing between the walls and was thus pre-heated by heat that would otherwise have been wasted. The fire-box was provided with firebrick walls that were found to be inadequate and were thickened to the extent that the grate-area was reduced to about 36 sq. ft, some 14 per cent. less than that of the standard Gresley Pacific, so that unless compounding and high boiler-pressure between them should produce some unaccountably great advantage, this large locomotive would be less powerful than those in common use on the LNER main-line trains.
Wilson, G.R.S. Report on the derailment which occurred on 1st September, 1955 at Westwood Junction near Peterborough in the Eastern Region, British Railways. Ministry of Transport & Civil Aviation: Railway accidents [monograph]. London, H.M.S.O., 1956. 10 p. + 6 plates (incl. 1 folding). 5 illus., diagr. (s. & f. els), 2 plans.
This accident (to the W1 locomotive) revealed inherent weakness in the design of the leading bogie side frames and stretcher bar.
Yarrow, H.E. Discussion on: Macleod, J. The steam turbine locomotive. Trans. Instn Engrs. & Shipbldrs. Scotl. 1929/30, 73, 49-79. Disc. : 79-108 + 2 folding plates. 14 illus., 6 diagrs., 2 tables, plan.
A feature of the discussion was the clash between Yarrow and Macleod over the latter's infringement of Yarrow's and Gresley's patent rights for water-tube boilers.
Yeadon, Willie B. Yeadon's register of L.N.E.R. locomotives. Vol.2: Gresley A4 and W1 Classes. Irwell Press, 1990.

Illustrations
W1 No. 10000 in original condition on Queen of Scots Pullman at Eryholme. Harry Dumas. Steam Wld., 1990 (34) 49.
Arman, Brian. L&NER 'W1' No. 10000. Rly Arch., 2009 (24) 54-6.
Three contact prints acquired at a railwayana auction of No. 10000 as running probably in 1938 at King's Cross shed (two views, one on turntable) and hauling a down express probably on Holloway bank.

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