William (Bill) Alfred
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In brief: Bill Tuplin must have been a delightful man who shared a love of steam locomotives with a fear that the automobile would kill the British countryside. But in spite of his engineering background his views on how the steam locomotive should have been constructed are frequently perverse and should be read with caution, sometimes with extreme caution. Ell's and Carling's comments on Tuplin's paper presented to the Institution of Locomotive Engineers need to be absorbed, before Tuplin's observations are cited as evidence. As the extract from North Western steam illustrates Tuplin was an excellent story teller, but is it fact or faction? His response to Cox's paper on the British Standard locomotives contains several gems from his caustic observations.
William Skeat's obituary in the Journal of the Stephenson Locomotive Society noted that Tuplin died on 7 March 1975 aged 72. William Alfred Tuplin was born in Birkenhead on 12 October 1902 and his childhood was spent in Huddersfield where at early age he learnt the varying characteristics of LNWR, LYR and GNR locomotives. He entered Manchester University in 1919 and graduated with honours in Mechanical Engineering in 1923. He joined David Brown & Sons of Huddersfield and specialized in the design of gears. He became Assistant Chief Engineer in 1937 and Chief in 1940 when he also became responsible for research & development. He was awarded an MSc for work on torsional vibration, and his DSc in 1939. In 1951 he was appointed Professor of Applied Mechanics at Sheffield University and retired in 1968, becoming Emeritus Professor. As an enthusiast he attempted to debunk what he considered to be perverse ideas and was a strong individualist who was prepared to defend his ideas even within the professional institutions. His vigorous and caustic writings masked a gentle, quietly-spoken, courteous man who was a sincere churchman.
KPJ: From a personal inspection of his works it is obvious that he was an environmentalist long before such ideas became fashionable, and considered that the motor-vehicle was killing the countryside. His love of the British rural scene permeates all his writings. He, like myself, was very conscious that travel by train combined the joy of experiencing the steam locomotive at work with a panoramic vista of the ever-changing countryside. The loss of steam traction has not removed this joy altogether, although travel by TGV across France brings an almost surreal dimension with the Alps visible beyond the series of nuclear power plants which are propelling the train at aircraft speed.. Even the HST on its mad dash from Bristol to Paddington now seems hectic after wandering through East Anglia: glimpses of Wales, the Cotswolds, the Chilterns and the Eurostar car sheds all visible within such a short time span. Tuplin is clearly a candidate for a more comprehensive Oxford Dictionary of National Biography, but at present is excluded in favour of trivial poets, such as Larkin. Furthermore, he is excluded from the absurd Oxford Companion to British railway history..
Although, he was a mechanical engineer of some standing he was not a locomotive engineer and is thus only represented within this section, rather than with the engineer authors, like Cox and Holcroft. His British steam since 1900 may be regarded as an alternate to similar compilations by Poultney and Nock. His observations can be perceptive (vide hammer-blow from the two-cylinder Pacifics, for instance), but the amount to be covered tends to make the text somewhat breathless compared with the more leisurely style adopted in his other works. By chance in 2012 KPJ came across Tuplin's very serious contribution to Andrew's theoretical paper on stresses in coupling rods (Andrews, H.I. Stresses in locomotive coupling and connecting rods. J. Instn Loco. Engrs., 1952, 42, 533-79. Disc. 586-90. (Paper 517)) where Tuplin's observations on resonant vibration are highly appropriate.
Rutherford contributes a considerable amount of space to Tuplin, and especially Tuplin's assertion that "the steam locomotive altered little in the century". (Backtrack, 2001, 15, 468). He also admits that "Tuplin's writings had a great influence in my thinking regarding steam locomotives." He is much harsher in his specific assessment below. Certainly, Rutherford's spikey style owes something to Tuplin's combatative stance (especially in his periodical articles - it was less marked in Tuplin's books) which tended to follow certain predictable patterns. It is not too difficult to imagine Tuplin's "Steam in the Highlands" or "Steam in North Norfolk" each of which would have scrutinized locomotive development in a broadly similar way, described in considerable detail, a trip viewed from the carriage or the footplate of a journey over the lines where it is difficult to know where fiction begins, and ended up with a 4-8-0 to Tuplin's design, presumably in these cases painted yellow. In this respect Tuplin shares something with Theroux in that it is sometimes difficult to establish where reality ends.
Anyone considering citing Tuplin in a serious study of locomotive development should read Carling's and Ell's responses to Tuplin's paper presented to the Institution of Locomotive Engineers.
Phil Atkins reacted to this web page by noting that he had once had Tuplin pointed out to him in the Reading Room at Boston Spa and by giving a full citation for an article by him entitled An ultimate steam locomotive The Engineer, 28 August 1964
Institution of Locomotive Engineers paper
Tuplin, W.A. (Paper No. 528).
Some questions about the steam locomotive. J. Instn Loco. Engrs., 1953, 43, 637-65. Disc.: 665-714: 1954, 44, 167-73. illus., 10 diagrs. 3 tables.
An outsider's (but a professional engineering outsider) view of locomotive development. The paper is interesting in that all of Tuplin's views aired in several books and many magazine articles were subjected to scrutiny by professional locomotive engineers (thus the response is especially interesting). Tuplin argued that the extra weight demanded for stronger boiler plates invalidated the "advantage" of adopting higher boiler pressures.
The following Tuplin criteria were subjected to Tuplinesque scrutiny by Carling:.
(a) The higher temperature of the water means higher temperatures
in all the main components and this can affect the copper firebox and copper
stays appreciably as that material begins to lose strength as the temperature
rises above about 300°F.
(b) The higher temperature and pressure of the water accelerates any chemical action of its impurities on the boiler.
(c) The thermal stresses in critical parts of the firebox wall may be increased by the effect of the greater thickness.
A key feature of Tuplin's paper, and one debunked by Ell was Table III best speed ranges on page 647 wherein the best speed range in terms of boiler/cylinder capacity and the best speed for valve performance were listed together with their overlap if any: there was alleged to be none for the GCR Director class, and only the range 50-59 for the King class: the latter was clearly perceived as a red flag by a bull by Ell!
Two cylinder designs were advocated as against the use of multiple cylinders: if multiple cylinders were adopted then he favoured the layout employed on the B16/2. Favoured narrow fireboxes and the absence of trailing axles. Cited Goss (this got him into a lot of trouble) to advocate the use of simple front ends as aginst multiple blastpipes and chimneys. He made a number of comments on the ergonomics of cabs and the operation of firehole doors.
Discussion: H. Holcroft (665-8) opened the discussion and on page 666 (when well into his response) Holcroft noted that: "In the Paper much prominence was given to thermal efficiency per se. To the locomotive engineer, however, thermal efficiency was only one factor of many and it had to be considered with due regard to all the others which went towards the making of optimum power. It might well be that in the end some sacrifice of thermal efficiency could be beneficial in producing the most suitable motive power unit. Holcroft was highly critical of Tuplin's assertions concerning low boiler pressures: "such engines were amiable and reliable machines but most lethargic" Holcroft was also highly critical of Tuplin's observations on firing methods, on superheaters, and on lost motion in valve gear due to excesssive clearances (and cited his own measurements to show that was not the case).
S.O. Ell (671-4) produced both a sweeping
condemnation of the overall thrust of Tuplin's paper and of its reliance
upon Goss's Locomotive performance
upon which Tuplin based much his study. Ell stated that Goss was probably
the first to give a rational explanation of the action of the front end.
But there was insufficient dimensional difference in the boilers" and. his,.
results were based on simple draught values, which were unsupported by values
of other quantities now known to be necessary to a proper front end analysis.
Some of his conclusions cannot now be supported. For instance, on page 256
of his book, Goss states that draught varies as the steam rate. But it is
a matter of routine in all modern controlled tests to find that draught varies
as the square of the gas flow and the gas flow nearly as the steam rate.
As the rate of evaporation increases, the work of expelling the gases rises
more rapidly than the increase in energy in the steam which results from
its rise in pressure and temperature so that a point is reached when the
rate of combustion cannot further increase. Clearly, the connection between
the blast pipe-chimney proportions and evaporative capacity must contain
a term to represent the resistance to gas flow; how to state this in the
form of a leading boiler dimension for a first approximation in design raises
a problem. The smokebox diameter proposed by Goss is too crude for Britisb
conditions of wide and narrow fireboxes, parallel and taper boilers, and
restricted construction gauge. Nor is the grate area suitable; consider,
for instance, alternative boiler designs for a given engine with a given
front end design; let the two boilers have the same evaporative heating surfaces
but appreciably different grate areas-narrow and wide fireboxes if you like.
It will be found impracticable to arrange for the resistances to be inversely
proportional to the grate areas, although the total resistance of the boiler
with the larger grate area may be less than the other. It is therefore impossible
to obtain as high a rate of continuous evaporation per square foot of grate
area from the boiler with the larger grate as we shall with the smaller,
although its total evaporation may be a little higher. With a good front
end we may approach the grate limit of the boiler with the smaller grate
but we shall not get anywhere near the grate limit of the boiler with the
larger grate, which is therefore unreal. There is then no alternative but
to turn to the evaporative heating surface as the most reliable, though not
altogether satisfactory, term to connect the front end proportions with
evaporative capacity, a practice in which we are in step with the
Goss does not connect blast pipe and chimney dimensions at all, which is surprising since there are practical reasons why they should be connected and no scientific reasons why they should not be. Goss ties the chimney choke to the roof of the smoke box and the orifice top to the centre line of the smokebox. These are too restrictive for British practice. In his illustration of Goss's proportions, Fig. 8, Tuplin omits to define the proportions of the chimney above the choke. Are we to infer that he considers this has no other purpose than to lead the gas-steam mixture to the outside? Mr. Ell would like to show the Author how the action here and in the choke is studied in modern practice when developing front-end proportions. Churchward's proportions as between blast pipe and chimney, dating from the same period as Goss's work, have never been seriously upset and it is interesting to note that Young produced in America long after Churchward and Goss, proportions which are almost identical with those of Churchward.
Ell dealt at length with the question of the grate area being an unsuitable basis for estimating the maximum continuous evaporative capacity because of the implications it has on Tuplin's "best speed range for boiler and cylinder capacity," Table III. Results from testing some of the locomotives which are represented in this table and which can be said to be fitted with draughting arrangements of equal efficiency can be shown to support the speaker's contention that the grate area as a basis for maximum continuous evaporation of the boiler is unsuitable. Indeed, 'on re-reading the Paper Ell wondered why our modern champion of Goss did not use the diameter of the smokebox for this purpose.
Mr. Ell said he could not accept the Author's "best speed for boiler capacity" at all. [For this reason KPJ has decided not to incorporate the information in the sections on specific locomotive designs]. It appeared that the Author is really trying to show whether boiler and cylinders are properly matched, but the flaw in his criterion is in placing too much reliance on his specific effort concept; this, in the speaker's opinion, is somewhat arbitrary and has little value other than as a convenient basis for plotting that otherwise most useful diagram, Fig. 2. Let us ignore the values of specific effort when applying it to two locomotive classes in his list, the WR " King" and BR 7, of which we know a great deal. For both, maximum cylinder efficiency occurs between 16 per cent cut-off and a specific speed of 0.46 ane 221 per cent cut-off and a specific speed of 0.3. For the" King" the train speeds are 87 and 55.5 m.p.h., and the BR 7 65.5 and 42.6 m.p.h.
Whether the boilers and cylinders are properly matched depends on (a) whether the boilers can supply the steam and (b) whether the steam can be supplied at a reasonable efficiency. Recent test results show that the requirements from the" King" are 19,000 lb. of steam per hour at 87 m.p.h. and 25,000 lb. /hr. at 55.5 m.p.h., which the boiler is capable of doing at temperatures of 645°F. and 670°F. respectively. These correspond to 56.5 per cent and 74.4 per cent respectively of its maximum continuous capacity, the overall efficiency referred to the cylinders being 11.3 per cent and 10.1 per cent respectively. The requirements for the BR 7, which can be read from Bulletin 5, are 16,000 lb./hr. at 65.5 m.p.h. and 17,000 lb./hr. at 42.6 m.p.h. which the boiler can supply at temperatures of 619°F. and 627°F. respectively. These correspond to 50.6 per cent and 53.8 per cent respectively of its maximum continuous capacity, the overall efficiency referred to the cylinders being 12.1 per cent and 11.7 per cent respectively.
Mr. Ell would like to ask the Author how he reconciles these conclusions with the implications concerning the same locomotives in his column A of Table III [Tuplin's best speed ranges], but he would make it quite clear that actual test results of these classes show that the maximum cylinder thermal efficiencies remain at practically uniform levels over a relatively wide steam rate range at high speeds. The maxima have almost identical values, the corresponding steam rates being 18,000-22,000 for the BR class 7 and 21,300-23,000 for the" King."
D.R. Carling (694-8) presented a lengthy and extremely sharp response to Tuplin's views. Much is quoted verbatim as it is considered that many may have read Tuplin's books without the benefit of external criticism. Others, notably Holcroft at length upon this paper, but Carling was singularly qualified to question many of Tuplin;s assertions..
Carling began by stating that there were some of Professor Tuplin's opinions with which one could agree, some with which one could not and a good many that lay somewhere in between, as was only to be expected. Professor Tuplin might rest assured, however, that quite a number of professional locomotive engineers did possess steam tables and some of them, including some of the greatest, had actually read, marked, learned and inwardly digested them!
If a boiler to carry a higher pressure were properly designed, its maintenance should not be very much higher than that of a similar, not identical, boiler carrying a lower pressure. Tuplin's points (a) and (c) could both be taken as advocating steel fireboxes for high pressure boilers and (b) as advocating the need for proper water treatment, but it was hard to understand why an increase of 26½oF. in boiler water temperature between 180 and 250 lb./sq. in. for example, was supposed to be almost catastrophic when the other side of the plate might well be 1,000° or more, hotter. Lowering the working pressure of an existing boiler to prolong its life, without incurring heavy expense, was an entirely different matter and was usually a consequence of corrosion. If such a practice must be adopted, the higher the original pressure the less pernicious the reduction would be in enfeebling the locomotive, but it would almost inevitably make the engine a less effective one.
Where would Professor Tuplin like them. to draw the line? Most recent designs of two-cylinder simples, both in Europe. and America, carrying pressures of 250 lb./sq. in., or over, did so because of limitation on the size of the cylinders. Should all locomotives have the largest cylinders that would pass the loading gauge and the boiler pressure be increased in proportion to the size of the engine? Was that not going a bit too far? Would Professor Tuplin say what he considered to be reasonable upper and lower pressure limits?
The "power output" of a boiler was a quantity rather like the number of calories in a pound of food, which might be there, but could not be extracted equally by everyone's digestion. The "thermal output" of the boiler had to be turned into power by engines of somewhat variable efficiency, variable between one and another and for each over its working range.
Tuplin was quite correct in his deduction about large grates but as he himself stated that large and wide were virtually synonymous, with what was he quarrelling? The report contained no pitfall for reasonably intelligent and well informed persons, unless they chose to dig it themselves. Many authorities had expresst!a a preference for the narrow firebox, as long as it would provide the necessary grate area.
Owing to the fact that the amount of first class locomotive coal available in Britain was decreasing year by year, and must be expected to go on decreasing, it seemed that locomotives with larger grates were advisable to be able to cope with the coal that might be available over their working lives. They ought to think of the kind of coal that might be supplied to the railways in 1974.
If Professor Tuplin would read Chapelon's treatise on the steam locomotive (KPJ's emphasis) he would find that this eminent and eminently practical locomotive engineer; whose designs had been singularly successful in meeting the requirements that they were intended to fulfil, had an even more analytical and theoretical approach to locomotive design than he had himself and had the advantage of a great deal of practical experience on which to base his theories. His conclusions differed a good deal from those of Professor Tuplin.
Fig. 2 was interesting (KPJ: related specific speed to specific effort to cut off and relative efficiency and led to Table III which quoted "best speed ranges" for a large number of locomotives), but it was built up on a very large number of assumptions and whilst these might individually be not far from the truth (and. in some cases the errors might tend to cancel one another), nevertheless, there were so many potential sources of error that the whole diagram could become sufficiently distorted to make very appreciable differences in the limiting values deduced from it. In a very broad sense, though, it showed a correct trend. The main errors could arise from several sources, but perhaps chiefly from the facts that the mean blast pipe pressure depended on the rate of steam flow and was almost independent of speed or cut-off, steam-chest pressure or temperature, that on all normal locomotives the inlet steam temperature rose appreciably as the rate of working increased and that, partly as a result of these two items, actual indicator cards would differ from the synthetic cards used in producing the diagram by varying amounts, some of which might be far from negligible.
Whilst Professor Tuplin's general argument based on this diagram was sound it could not be regarded as precise in actual values. P.W. Willans showed in his paper to the Institution of Civil Engineers in 1893, reporting the results of a classic set of steam engine trials, that there was a maximum ratio of expansion for steam economy for any reciprocating engine: the locomotive was just such an engine. Exactly what this minimum cut-off was in various circumstances would only be found by actual tests. It was quite true that a reasonable degree of part-regulator working made virtually no difference to the steam consumption and certainly was often mechanically kinder to both machine and crew. When less power was needed first the cut-off should be shortened as much as the particular engine would stand without too much knocking and vibration and then the regulator opening reduced. With most locomotives in reasonable condition not much would be lost, if anything, on the steam consumption and much might be gained in maintenance. In some cases, too the vibration due to excessively short cut-off working might spoil the firebed and thus increase fuel consumption indirectly. Most locomotives handled in this way would keep them inside the range of reasonable thermodynamic economy.
An increase of about 3 per cent in the amount of steam passing the blast pipe orifice would raise the blast pipe pressure from 4.3 to 4.6 lb. /sq. in. in gauge, not to 6.3 lb./sq. in. In any case was not the Author [Tuplin] here logically busy proving that one of his own basic assumptions was wrong? Either the back pressure was one tenth of the steam-chest pressure or it was not "Reductio ad absurdum!"
Professor Tuplin was quite right about the unreliability of cutoff figures and he would realise that it was not for nothing that curves in British Railways' locomotive test bulletins showed lines of constant steaming rate in full and lines of constant cut-off dotted.
There were good reasons for having as few cylinders on a locomotive as one reasonably could and other good reasons for having more. Sometimes one lot of reasons would plainly outweigh the other, but often it was a matter of personal opinion, which was likely to be based on personal experience, which often meant on tradition.
The remarkable thing about the Goss front end proportions was that neither the blast pipe cap diameter nor the chimney top diameter nor its height above the choke were even mentioned, whereas these were quite as important as anything he did mention. The work of Strahl, brought up-to-date by Meineke, was a far better guide in those respects, but actual trial and adjustment was the only way to get as near the best proportions as was practicable. The less ironmongery, especially moving ironmongery, there was in smoke boxes the better, so it was very important to know what benefits its use could bring and at what cost, for, in such matters, they could not get something for nothing. Chutes for smoke box char that did not lead to failures ought not to be beyond their ability to contrive, but they now seemed settled on the policy of spreading their char over the United Kingdom as a whole instead of over the loco shed yards and their neighbourhood.
Of all the mechanisms the Author might well have criticised, those often used for operating cylinder cocks and ashpan damper doors were not mentioned, though they were far more prone to failure than the example he did quote.
An inward opening firedoor, as suggested, was excellent as long as the hinges worked properly: It could be made hollow to admit a small amount of top air if required. It might be better from the combustion angle to admit a small amount of top air just over the fire at the front and sides of the firebox rather than at the back only, but any gain in fuel economy could well be nullified by added maintenance of the boiler and possible loss of availability.
As Professor Tuplin had referred to the age of the steam locomotive Mr. Carling thought it a suitable occasion to quote the late Lawford Fry's dictum to his class of students at the former Locomotive Research Institute in the United States:-" A thing is not necessarily good because it is new, or bad because it is old. It has been customary to make wheels circular for over 4,000 years and that is still the best shape to make them."
W.O. Skeat (679-81 written communication)
challenged Tuplin's statement: "raising the working pressure
does not increase the power of the boiler, but rather the reverse," made
one ask whether power station engineers, who were given to. using much higher
pressures (1,000 to 1,500 psi or more) than locomotive engineers, really
knew what they were doing. Surely the answer was to be found by scanning
the specific volume figures in steam tables, which gave a clue to the much
greater internal energy per pound of steam when high pressures were adopted.
Tuplin seemed to favour reducing boiler pressure to save boiler weight, but
would like to see a high superheat, to compensate for the lower total heat
of steam which would otherwise result from the adoption of the lower pressure.
A point to remember here was that:-
Total heat of superheated steam =Sensible heat+latent heat + superheat.
The extra heat units represented by the superheat portion of this energy equation were given by the difference between the actual and the saturation temperatures multiplied by the specific heat of superheated steam, which was not unity, but was around 0.48. In other words a big degree of superheat suffered a considerable come-down when regarded from the energy, instead of the temperature viewpoint.
The view was commonly held that there was no point in superheating steam to such a temperature that it was still superheated when exhausted. Tuplin appeared to subscribe to this view. Yet on this important matter there was by no means an identical outlook amongst experts. Thus Inchley's Theory of Heat Engines; ed H.W. Baker states: "It is to be expected that when a sufficient degree of superheat is employed to prevent cylinder condensation, the gain due to still further superheating will be small." But no less an authority than Ralph P. Johnson, Chief Engineer, Baldwin Locomotive Works wrote:- "The presence of any superheat in the exhaust is frequently regarded as an evidence of too much initial superheat. This is incorrect, as the real measure of cylinder performance is the amount of heat converted into work in relation to the total heat supplied to the cylinder. For any initial pressure, there is less heat passing out of the cylinder, or per unit of time, with increased initial temperature. For example, with 225 psi initial pressure and 500°F initial temperature, 16,300 BTU are exhausted per ihp/hour. When the initial steam has a total temperature of 700°F., only 14,800 BTU are exhausted per hour, in spite ot the higher exhaust temperature. There is also a decreasing amount of heat in the exhaust steam with increasing initial pressures for any given initial steam temperature. For example, with 700°F. initial temperature, the heat in the exhaust steam will be reduced from 14,800 BTU at 225 psi initial pressure to 12,300 BTU at 350 psi initial pressure. Unfortunately, Johnson did not give fuller details to show how these figures were derived. The Author's comments in them (assuming them to be correct) would be of interest, in view of the importance evidently attached to the point by Johnson, in contrast to the contention in Inchley that any gain due to superheating beyond the temperature necessary to prevent cylinder condensation would be small. It should be noted that Skeat's surgical treatment of Tuplin's paper did not hinder his subsequent generous obituary..
Diamond, E.L. Development of locomotive power at
speed. Proc. Instn Mech
Engrs., 1947, 156, 404-16. Disc.: 417-43.
W.A. Tuplin noted that Fig. 6 was of particular interest to himself. From this it would be seen that while the steam pressure varied from 140 to 280 psi the rate of steam consumption varied very little indeed. Actually it varied proportionately even less than that diagram suggested, because the origin was not on the diagram at all, but ten units below. The variation of steam consumption with steam pressure was therefore very low indeed, so that there was not much gain in efficiency by raising the pressure. The diagram was based on a constant steam temperature of 600 deg. F., so that the coal rate was proportional to the steam rate.
Since the efficiency was not appreciably improved by raising the pressure, he had wondered why there had been a tendency to raise it. True the cylinders could be reduced in size, but that seemed to him to be a very small advantage to set against the greater weight of the boiler, which meant that, unless the higher pressure produced higher efficiency (which was not proved) the power/weight ratio of the locomotive went down as the pressure went up. Possibly locomotive engineers had been influenced by Churchward's practice, a feature of which was a rather high pressure, and that had been assumed to be a vital factor; he personally thought that was not the case.
Another consideration which might have influenced locomotive engineers was the fact that in power station practice, over the last twenty-five years, boiler pressures had gone up from 250 to something like 1,000 psi with very substantial gains in efficiency. That argument, however, was quite fallacious, because the efficiency which was obtained depended almost entirely on expansion ratio, and in a power station it was possible to attain almost any expansion ratio desired by putting in sufficient stages. The locomotive, on the other hand, did not expand down to 1 psi, or even down to atmospheric pressure, but down to a certain fraction of its boiler pressure. It was not possible appreciably to alter the expansion ratio by altering the pressure, so that the efficiency was not, theoretically, improved appreciably when the pressure was raised.
One could usually get a coal consumption of about 3 lb. per drawbar h.p.-hr., and the scatter round that figure seemed to be almost independent of pressure. The designer might present the results in such a way as to conceal unfortunate aspects of the work. Table 1 was a comparison of what happened at 206 psiand 294 psi. In it the higher steam pressure gave the lower steam consumption throughout the range. At 206 psi, the steam consumption decreased as the cut-off was advanced (the expansion ratio was increased)-in accordance with theory. At approximately constant cut-offs, however, the lower pressure gave higher efficiency for a given expansion ratio.
This was well known to some people*. A change of pressure from 180 to 220 psi on the LNER Pacifics did not, on test, produce any reduction in coal consumption. It might be said that enough had been heard about coal economy lately; that the real criterion of ability to develop power at speed was the ratio of mean effective pressure to steam chest pressure, and that high pressure should improve it. He himself did not think so. The steam had fleeting opportunities of getting into the cylinder through a very narrow opening, and its capacity to get in depended on its quickness "off the mark". He suggested that that would be associated with its energy per unit weight. At a constant temperature of 600 deg. F., the energy in a pound of steam was slightly less at 10 psi than at 300 psi so that high-pressure steam did not move any faster, and was not quicker at getting in. He thought the velocity of propagation of a wave through steam, proportional to the square root of the absolute temperature and independent of pressure, might be a criterion. It was possible to get the steam to move faster by raising the superheat, but the advantage was small less than 5 per cent if the temperature were raised from 650 deg. F. to 750 deg. F.
If a boiler pressed to 300 psi were fitted to an engine designed for 200 psi the performance, as regards acceleration and speed, would improve, provided it did not slip, and the coal consumption might be reduced-the tractive effort had increased; it was possible to work at a lower cut-off, and therefore the efficiency was higher. But that result could be obtained without increasing the boiler pressure, simply by enlarging the cylinders and valves suitably. He considered a cylinder 20 by 26 inches, with 10-inch valve, 1½ inch lap, and ¼ inch lead. At 24 per cent cut-off and 420 r.p.m., for steam to get into the cylinder and fill it to the steam-chest pressure would involve a mean velocity through the port of 1,650 ft. per sec., approaching the speed of propagation of a wave through steam. The steam would not do it. There was no need to bother to take indicator diagrams to find whether the top of the diagram was flat; it could not be flat. Incidentally, the speed with which the steam had to get out of the cylinder was only 300 ft. per sec., which tended to disprove the legend that it was easier to get steam into a cylinder than to get it out. To obtain a high ratio of mean effective pressure to steam chest pressure it was necessary to have a high ratio of area of port opening to cylinder volume. Secondly, to save coal it was necessary to have a high expansion ratio and no leakage. Thirdly, to save water it was necessary to have a high superheat and no leakage. Fourthly, to secure a high power/weight ratio one needed the lowest practicable boiler pressure and no leakage. High pressures tended to promote leakage.
* WINDLE, E, . 1931 J1. Inst.Loco.E., vol. 21, p. 178, "Some Notes Relating to Cylinder Performance''.
Response to Cox paper on Standard locomotives: Cox,
E.S. British standard locomotives.
J. Instn Loco. Engrs, 1951,
41, 287-335. Disc.: 336-403 (Paper No. 502). Copies of
the full paper are available from the IMechE's electronic archive.
Dr. W. A. Tuplin (A) said that the proposed standard locomotives in general were much larger than the locomotives that had been used in the past for similar duties. This appeared to indicate the acceptance of the low war-time qualities of coal and maintenance as a permanent feature of locomotive operation. It confirmed the general opinion as to what might be expected from nationalisation and planning.
Looking at one class of locomotive and thinking about what could be observed in daily practice, it was difficult to feel very pleased over the use of an 86 ton 2-6-4 tank engine for work that had been done regularly in the past by a 40 ton 0-4-2T. The argument that the big engine could do much heavier work when necessary was completely defeated by the fact that in actual practice, generally speaking, it never did.
If the excessive power that the big engines ought to have were used to regain lost time by fast running, that might justify it, but there was no instruction to engine drivers to this effect, and it rarely happened.
It had recently been stated officially that the use of Class 7 Pacifics on the Eastern Region would enable the running time from London to Norwich to be reduced by ten minutes. That was something, but it was not addedhoweverthat even so the time was still perceptibly longer than that allowed to the Holden 4-4-0s [sic] used with comparable loads about forty years ago.
It was stated on page 310 that the majority of locomotive work under British conditions is undertaken at moderate output . . . As a frequent passenger on British Railways, let him say feelingly, Youre telling us. It was also stated (page 298) that the 4-6-0 with its 17 ton axleload should take the place of many 4-4-0 types. It certainly should be able to do the haulage work of many 4-4-0 types, but it would be equally fair to say that what was previously done by a 50 ton 4-4-0 would now have to be done by a 69 ton 4-6-0.
He asked whether, if the new standard engines had to be sold in competition, the present designs would have been offered. As a taxpayer he felt a slight uneasiness at the multiplicity of Pacifics in the new standard designs, and he asked as a specific question, On what British route limited to 19 ton axle-loading is there traffic at present, or expected in future, that could not be handled by a 4-6-0 maintained in reasonably good condition ? To that he would add a further question : Is it realised by designers how pathetically impotent even a Pacific may be if maintenance is not good ?
He was also constrained to remark that in this country at present there were some 300 Pacifics, and that, he suggested, was far more than was necessary to do all the work that reasonably demanded Pacific-sized locomotives.
One reason given for the use of oversize locomotives was that thermal efficiency is sought by large grate areas promoting low rates of combustion. In actual practice, it had became a ,practice on some routes to load up these large grates with tapering fires so that about a third of the area contributed 90 per cent. of the combustion. In these circumstances, one wondered whether the high thermal efficiency from the large grates was actually achieved. It might not be known yet at the higher levels of the Railway Executive that there was now a practice with certain firemen to put enough coal in the firebox whilst the train stands at a station to feed the engine for the next hour. Presumably he asked the driver to keep an eye on the water and then dozed gently until the next stop !
It was stated on page 289 that thermal efficiency was sought by high degree superheat, but neither theory nor practice encouraged this hope. On the other hand, a large superheater might be advantageous simply because it automatically gave a larger flue gas area. In other words a large superheater may help, even if high superheat does not.
He noticed that the self-cleaning smokebox was included as a standard feature. This device was brought from America where a high proportion of the mileage was in thinly populated country and where most of the coaches did not rely on open windows for ventilation. In this country conditions were different, and here he would suggest that the self-cleaning smokebox was a little anti-social in its grit-spreading activities. Would it not be possible, with an extended smokebox, for the char to be discharged downwards into a hopper that could be emptied easily into a pit between the rails ?
The construction of the reversing gear was, of course, admirable. One wondered why it was not done a hundred years ago. The cut-off indicator seemed elaborate and ponderous. The gears used to turn the indicator were big enough to drive a reasonxbly-sized motor car, and perhaps something lighter might be devised.
It would seem that the universal joints at the ends of the cardan shaft would not be necessary if the screw and the outgoing shaft from the cab were placed with their axes in the same line. That could be done, and universal joints would then be unnecessary.
Locomotives were not completely rigid but only a very slight degree of flexibility in the couplings would suffice if the shafts were in line.
It was stated that the blower valve handle was easily accessible to the driver and the fireman, but he must disagree with that: it was not easily accessible to the fireman just when he wanted it most; that was to say, when flame came out of the fire-hole. Two handles for the blower would seem to be as justifiable as duplication of the whistle handle.
He was surprised at the guarded reference to the shape of the chimney on the Class 7 Pacific. It was as near to pure Honvich as could be expected !
On a point of detail, he regretted that the opportunity was not taken to start a rational numbering system. The needs of a numbering system were three: firstly, to cause the number to indicate the class of locomotive; secondly, to use the minimum number of symbols; and thirdly, to avoid any need to renumber any of the existing locomotives. On the introduction of a number of standard classes, it would seem to be a simple solution to give a letter for the class, followed by a number for the individual engine, starting from 1 and going upwards. On that basis-provided one did not exceed 999 locomotives in any one class-no number need have more than four symbols.
Despite the questionable features of the locomotives here and there in principle and detail, the design staff were to be congratulated on achieving such results from four main offices between which there must previously have been rivalry rather than single-purposeco-operation.
Those who had a sentimental attachment to the steam locomotive might indeed be glad that any further development was contemplated at all, particularly in view of the rather striking British Railways poster entitled Trains of our Times. It depicted a multiple unit electric train in somewhat sickly green, a red and white main line train hauled by two diesel electrics, and in the background a woebegone Class 5 4-6-0 priming dismally.
An ultimate steam locomotive. Engineer, 1964,
(28 August), 330-4.
In this he compared his proposed 4-cylinder simple 4-8-0 operating at 200 psi with the Chapelon 4-8-0s and the BR Britannias. This received an invited response from A. Chapelon in The Engineer for 30 July, 6 August and 13 August 1966.
Comparing locomotive performances. Rly Gaz., 1942, 77, 219;
A matrix to assist comparative studies.
Double chimneys. Rly Wld, 1964, 25, 161-3.
Argues that only effective at high power in relation to loading gauge height, high speed and at high combustion rates.
Dimensions of locomotives. Loco. Rly Carr. Wagon Rev., 1951, 57, 179-80.
The author concluded that, with the exception of gas passages, dimensions are not critical in steam locomotive design.
Locomotive work evaluated. Rly Mag., 1952, 98, 348-9.
Motive power of the future - the case for steam. Trains Ann., 1952, 94-6.
No more wizards? J. Stephenson Loco. Soc., 1965, 41, 164-5.
Significant figures. Rly Mag., 1958, 98, 12-14. diagr.
Tuplin could see little point in C.J. Allen's method of train recording and has tended to criticise it and even parody it. C.J. Allen replied to this article in his usual series (Rly Mag., 1952, 98, 186-91) which resulted in Tuplin's "Locomotive work evaluated" (above)
Sketches for an expanded "Claughton". Rly Wld, 1963, 24, 414-16.
A 4-8-0 based on the Claughton four-cylinder layout, but with larger boiler, smaller coupled wheels and longer stroke cylinders.
Some railway speed records. Rly Mag., 1954, 100, 353-5.
An examination of some British records.
Was there any progress in steam locomotive design? Rly Wld, 1963, 24, 109-10.
Author's answer: there was not any. Rutherford has returned to this recently.
British steam since 1900. Newton Abbot
(Devon), David & Charles, 1969. 200pp. plates. illus., diagrs., tables.
This is a well organized book: there is a wealth of tabulated material and the illustrations are apt rather than decorative. The bibliography is in reality a list of references cited, but it is also well arranged. The book is completed with an excellent index. It followed Jones, and is therefore absent from it.
Great Central steam. London: Allen & Unwin, 1967. 234pp. + plates.
Great Northern steam..London: Ian Allan, 1971. 208pp. + 32 plates.
Great Western Saints and Sinners. London: Allen & Unwin, 1971.
Preface: In view of the constant reshuffling of laudatory information about the Great Western Railway in books published in the last quarter-century , the reader may think that there is something very odd about mentioning 'sinners' at this stage. It is in fact merely the consequence of recording observations made without privilege and consequently without obligation. In this subject one did not need to go to the bottom of a well to find truth; it sufficed to go on to overbridges, on to station platforms, and into trains and to use one's eyes, ears and nose. One might also go into sheds and works where a steel tape-measure could find figures that would astonish compilers of lists of officially-quoted dimensions of Great Western locomotives.
Great Western Steam.. London, Allen & Unwin, 1958. xiv, 193 p. + front. + 16 plates. 35 illus., 12 diagrs. (incl. 6s. els.), 6 tables.
This book contains a critical assessment of locomotive development. plus notes on footplate journeys. The illustrations are accompanied by detailed captions. 45671 (John Powell) reviewed this in Trains Illustrated, 1958, 11, 479 and includes the implication that Tuplin's observations "are all too often a series of splashes into other pitfalls than the one they already know they are in" and "The serious student of Swindon locomotive practive will learn little from this book." Full review below. .Long extract under Churchward
Great Western steam. London, Allen & Unwin, 2nd ed. 1965. xiv, 194 p. + 16 plates. 35 illus., 26 diagrs., (incl. 14 s. els.), 6 tables.
This edition contains an extra paragraph and more diagrams.
Midland steam. Newton Abbot: David & Charles, 1973. 260pp.
Ottley 12368: this book is remarkable, and should be known, for the eccentricity of some of its index entries: notably Jiggery-pokery [actually refers to ploys developed at Bromsgrove to maximize work for the banking engines]; Ramshackle [Baldwin locomotives], Uncertainty [statistical, but why not state so], Walking round engines in motion [three references, presumably to eccentrics in motion] and Wizardry
North Eastern steam. London: Allen & Unwin. 1970.
Ottley 12436: Rutherford, Michael. A Brief Survey of the Irish 4-4-0. Part 1: Genesis or how the Irish designed a "Crewe" 4-4-0 and exported it back to England. Backtrack, 2006, 20, 360 critices Tuplin's interpretation of the early departure of McDonnell from the NER and on page 364 notes that "What is alarming about Tuplin's book is that it was published in 1970 and in his Preface aknowledges the archivist of the Historical Records of the ex-NER, then at York... but does not seem to have looked at any relevant material".
North Western steam. London, Allen & Unwin, 1963. 251 p. + front. + 16 plates. 37 illus., 21 diagrs., 4 tables. 2 plans.
Ottley 6393b see also extract. Reviewed by J.T. in Rly Wld 1964, 25, 118..
The steam locomotive: its form and function. Bath: Adams & Dart, 1974. 158pp.
Ottley 10470: this shares much in common with British steam since 1900, but extending into a study of the steam locomotive as such (there is a chapter on the boiler and another on the chassis and the mechanisms thereon and another on routine maintenance). The book also provides a thin study back to the origins of the steam locomotive and across the Atlantic and into Continental Europe. Hidden within its text there are Tuplin observations on blow-backs and on the Gresley-Yarrow high pressure compound locomotive; the Paget locomotive and Bulleid's Leader class. His observations (pp. 78-9) on coal and its combustion demonstrate the author's scientific pedigree. The following extract from page 47 shows some of the book's strengths..
It can be said at once that no single type of variable blast-pipe ever gained anything like universal acceptance. The MacAllan blast-pipe cap was mounted on a rod that extended across the smoke-box close to the top of the blast-pipe, but clear of the steam that came from it. When it was judged advantageous to use a smaller blast orifice, the rod was rotated (by a crank linked to a lever in the cab) to turn the cap through a right angle and to place it firmly on the fixed blast nozzle. The device was an official mechanised version of the engine-man's unofficial restrictor. It had to be clearly understood that movement of the cap whilst steam was coming from the blast pipe was highly dangerous because during transition the cap might direct steam into the tubes and then flames would be forced into the cab even past the edges of a closed' fire-door.
W.A. Tuplin. Farewell to steam: riding the footplate of a Pennsylvania
4-4-4-4. Rly Wld, 1955,
Englewood to Fort Wayne in 1949 on T1 locomotive hauling 1000 ton passenger train at an average speed of 70 mile/h.
Tuplin's professional literature
Torsional vibration. London: Pitman & Sons, 1966. xii. 193pp.
Involute gear geometry. London, Chatto & Windus: 1962. pp. 188.
The Hull job
Most of what follows is self-explanatory: for a time the LNWR worked trains through to Hull and back with its own locomotives. It was a long run and one assumes that Tuplin's description is partly fictional, especially the loss of the firing shovel on the return leg climbing towards Standedge. Nevertheless, it is obvious that Tuplin must have got to know the Manchester to Huddersfield line very well in his student days and this (and KPJ's own fondness for the Hull service over the Pennines) that this section has been selected.
My nephew Jim (said the old man) had always been crazy about engines. Even though as a child he had lived alongside the North Western main line he went on thinking that locomotives were the best things in life and no career but that of a locomotive engineer ever had any appeal for him. As soon as it could be arranged he became a 'Crewe apprentice' and at the time of this story he had spent time in several departments of Crewe works and on engines as fireman, sometimes officially, sometimes not.
Through all this he continued to hold that the London & North Western Railway was the finest institution in the world, and even when he was sent to work as a fitter in Edge Hill shed he still believed it. The filthiest job in a filthy smokebox he did as a bit of homage to the whole race of North Western engines. He tried his hand at every shed-job so that he could expect to know the engines inside out and I believe he did.
He described his interests to anyone who would listen to him, he told them what he'd done and what he intended to do. There was never a more enthusiastic Crewe apprentice nor one who impressed his supervisors more favourably. I rather think he enlarged too much on his firing experience and the running foreman may have got an exaggerated idea of what Jim could do on the footplate. Otherwise Jim would hardly have been picked to go as fireman on the Hull job on a day when the regular driver was off sick and the regular fireman took his place. The 1914 war had been on for a year and at most sheds things were not quite what they had been, but even so, the Hull job was along one for a lad. .
To Jim it was a gift from the gods. He got a call-boy to tell his landlady he would not be in for tea and to pick up some food from a corner shop and he joined Alf (I never knew his other name) on 1081 John Keats, the regular engine for the Hull job. She was one of the few 'Prince of Wales' superheater 4-6-0s running at the time and she was kept in tip-top condition and as clean as when she first came out of Crewe Works.
Of course the 'crack' engine at Edge Hill then was the 'Claughton' that worked the eleven o'clock London and that day it was 668 Rupert Guiness. I expect that the shed-staff and enginemen were a bit hazy about some of the North Western engine-names such as John Keats but they could guess who Rupert Guiness might be. But even if you couldn't read, you were bound to notice the shine on 668 and 1081 as they left together, for Lime Street, to work the two eleven o'clock trains. They were not short of cleaners at Edge Hill, even though there was a war on, and there .was man-power enough to give the top-link engines a polish to be remembered. Jim had often watched them go and later in the day would occasionally work out where they were and imagine them speeding south or east. To be the fireman on one of these jobs made this the day of all days for Jim and everything he could see was just about right.
It was a bright calm day and according to Jim the birds were singing. As it was November, he may not have been absolutely right on that point, but you get the general idea. As they slid down the bank to Lime Street through the tunnels and under the bridges, the sun sent slanting rays over the top of the deep rock cutting and though it did not shine squarely on the engines, Jim felt that it would have done so if it could and would then have justified him in likening them to knights in silver-edged armour. He mentioned this to Alf who looked a bit puzzled and didn't brighten up much even when Jim recited a bit of the Ode to a Grecian Urn. If he did connect the poem with the engine (as Jim had done) he was perhaps made thoughtful by doubts about 'Its loveliness increaseth'. They had 250 miles to do before they got back and things can happen in that distance. And anyhow a fireman who suddenly gets his driver's job for a day has pretty lively thoughts of his own. What a run he is going to make of it, if he is on top of the job, or what a weight of responsibility if he is not.
Alf had looked after the fire at the shed as Welsh coal is tricky at the start of the day and with 1 in 93 for a mile and a half out of Lime Street it is as well to have everything just right. After the engines had separated at the home signal 1081 backed down into No.4 and Jim coupled her up to her train. The 'Claughton', with a longer train, stood under the bridge off the end of No. 7. As they waited for 'time' Jim was breaking coal, watering the dust and wondering how black he was going to get. Alf turned the blower on to liven the fire enough to get the full 175 lb. pressure by eleven o'clock. He then pottered round a bit with the long oil-feeder, putting spots of oil where he thought that they might do a bit of good just as most drivers do even when they are sure their oil-trimmings are all right. They had 'nine on', about 250 tons, and did not really envy the men on the 'Claughton' with about 420. Jim had been itching to get away and as soon as they did, he picked up the shovel, but Alf stopped him and told him not to put any coal on until they were passing the shed. So Jim was free to look outside a bit and what he saw was not bad. Although the London had got off the mark before them, their lighter train gave them an advantage. Besides that, the London stopped at Edge Hill and had time for conditional stops at stations further on, whereas the Hull was booked to make Manchester in forty minutes with a two-minute stop at Earlestown. When you add the fact that a passed fireman is always in a bit of hurry you can see why 1081 went right by the 'Claughton' as though she had been on a goods train.....
They had not much to worry about as they had a banking engine to help them up to Miles Platting, but Alf went at it as if they were on their own and they pounded through Victoria Station in fine style. As they did, Jim, looking ahead, had quite a shock. There's a road bridge with very deep plate-girders at the far end of Victoria, and Platting bank rises up behind it and passes out of sight as if into the sky. Jim had never seen a 1 in 59 before and could hardly believe they were going up there. But they did and they came to Millgate Box, which reminded Jim that it was again up to him.
He was finding firing to be not quite so pleasant as it used to be and there were some pretty heavy lumps in this Welsh coal, but there was the fire, dazzling white, and there was the blast pulling away at it and keeping it as hungry as ever. So he plugged about twelve in and after half a minute, to his delight, she started to blow off. So on with the injector and have a look outside for a bit. There's not much of what you could call scenery on Platting bank but if you are looking for points of interest you notice where the gradient changes from 1 in 59 to 1 in 49 just past a signal-box called Newtown but you can't see anything that looks new. Dismal, dirty and steep, that's Platting bank. Towards the top you bend left under a bridge carrying goods lines and there's a Before it banner-signal with a notice saying that you may pass it at' danger' as it is only repeating Collyhurst home signal which is not yet in sight because of the curve and the bridge. If you do see the banner-signal at danger you ease the regulator and whistle loud and long to remind Collyhurst that you are on your way. If you get stopped at Collyhurst home with a big train the chances are that you will not get away again without help. But that doesn't take long as there are always a few shunting engines close by and they are used to coming to the rescue round here. There was no trouble that day with 1081 and a banker). In fact .Jim thought that they were going a bit fast for the right-hand bend off the Oldham line at Miles Platting Station. Ahead was a length of straight with plenty of bobbled-topped L. & Y. signals. Behind was the train on the sharp curve and behind the train was the banker just dropping off. Jim took one look at the view mills, chimneys, gasworks and smoke and thought he might just as well put a bit more on the fire. He was not so fresh as he had been at Edge Hill but he slung in another round, one in each corner, two down each long side and one on each short side and came back to his seat to find her tearing on to Clayton Bridge with another rise then in front of her. A roll or two over the junction at Droylsden, where Alf gave her another notch, and Jim thought she would take another round of coal.
After that they were passing Ashton Moss and Jim noticed a big Great Central goods engine. Looks bigger than any of our goods engines, he thoughtt and in a different style too. He was a North Western man but he could see that there were perhaps one or two reasonable engines on other railways.
After she had bounced over a couple of junctions Jim saw nothing interesting ahead and gave her another round. Back on his seat he found them winding through a grimy cutting under a succession of road bridges. Out in the open they were faced with signals, crossings and cotton mills and Alf made a quick run in to Stalybridge. Short sharp runs on this job, thought Jim; you could almost call it a milk-round. The steam was down at 165 and so Alf had a look at the fire. 'Put plenty at the front when we get away,' he said. After five minutes, off they went up the Micklehurst loop, Jim plugging them in and finishing with an extra four shovelfuls at the front.
They were getting into the hills now and Jim was not sure that he liked the look of things although 1081 was not doing too badly. After a mile or so he supposed she could do with a bit more (she seemed that type of engine) and so he gave her another round taking it rather steadily, no point in rushing, he thought, in fact when you came down to it, he was not sure that he was able to rush. Some of these lumps were pretty heavy and it was a kind of Welsh that doesn't break easily. When you hit it with the coal- hammer it spits back at you. So he spent a bit of time breaking the big pieces and then heard Alf open her up a bit more; they were evidently coming onto steeper grades. So he gave her another eight with two more for luck at the front end, checked that the water level was well up the glass, and had another look outside. still pretty bright sun, but rather grim scenery and no hint of birds. They were winding up sharper grades now and the old girl would soon be wanting a bit more. 'Little and often' thought Jim and made a round of six instead of eight. After a minute or two he was thinking of having another go when Alf had a look at the fire and then said 'She'll do now to Huddersfield'.
As they went, pounding hard into a tunnel, Alf shut off the injector and sat, Leave the feed off till after we've picked up at Diggle'.So she slogged up to Diggle with the water dropping in the glass. Alf eased her just the least bit on the crossover and as they went into the long tunnel, he came down, dropped the scoop and filled the tender from the trough. Then he notched her well up and eased the regulator to do the three miles of level at about forty-five. There's not much joy in tunnels but at least the fireman can rest in this one.
There's a warning bell near the far end because there is a sharpish curve as you come out and then you have about eight miles down-hill to Huddersfield. You can run all the way quite fast without steam but Alf did not shut off altogether till they had gone nearly a mile past Marsden. The line runs down one side of the Colne Valley and on the other, as Jim noticed, was a main road with tram-cars well out into the country. Grimmish country he thought, with unfertile-looking fields separated by low black stone walls. till the valley ahead were mill-chimneys as far as he could see. They were running without steam faster and faster although the line had plenty of curves. Alf's hand was on the brake and once or twice he almost applied it but then changed his mind and let her roll. And she did! On an S-bend through Slaithwaite Jim was not a bit happy. Round the corner at Linthwaite the big superelevation was about right for their speed, but when they crashed and bounced over a crossing at Longwood Goods with another S-bend in the next mile, Jim was relieved to hear Alf putting the brake on a bit just to make sure it's still working perhaps but even so Jim thought they were still doing sixty as they dived into Springwood Tunnel with Alf now braking hard. Down through Huddersfield Tunnel it's 1 in 96 right into the station at the tunnel-mouth and so you need your brakes. It's not a wet tunnel but Alf dropped sand just the same. They came out well under control and Alf made a nice stop in the right place.
GREAT WESTERN STEAM. By Dr. W. A. Tuplin.
George Allen and Unwin. 25s.
Dr. Tuplin's new book, following closely on the heels of H. Holcroft's authoritative work on the same subject, must inevitably stand judgment alongside it, and will be found wanting. Mr. Holcroft recounted history as seen from the "inside", a factual study, interlaced with personal experience and accounts of schemes, experiments and trials and the reasons behind them. In this book, after an opening on the aesthetic merits of double-framed engines as seen through a boy's eyes, G.W.R. locomotive practice is dealt with in a curiously vague manner. Too much of it is laced with "apparently" and "it seemed that. . ." and persistently Dr. Tuplin the would-be C.M.E. intrudes to show what he would have done in Churchward's shoes. How easy, forty years after, to do sobut how easy even now to fall! These views, to professional locomotive engineers, are all too often a series of splashes into other pitfalls than the one they already know they are in, and are the butt of scorn, as Dr. Tuplin found some years ago when he set out to bait the Institution of Locomotive Engineers. All his usual hobby-horsesthree cylinders, single-axle drive, low boiler pressure, valve proportions, etc., are brought out of the stable and given another good canter. The last third of the book is devoted to accounts of footplate work and of specific footplate trips. Some clearly spring from personal observations, though they are in very general terms, while others could more properly be described as semi-technical and slanted story-telling which might well grace the pages of the more enlightened boys' magazines. This section is an unbalanced collection. and seems to ..t out to prove that the undoubted G.W.R. esprit de corps among footplate staff arises from doing a job under the worst conditions. The serious student of Swindon locomotive practice will learn little from this book that is not available elsewhere in better form. "45671"