Journal Instiution Locomotive Engineers
Volume 37 (1947)

Steamindex home page  Updated 2009-11-04

Key file

The IMechE virtual library is accessible (full papers, all diagrams, photographs, extensive tables, etc).at www.imeche.org.uk.

Journal No. 195

Walter, A.J.R. (Paper No. 463)
A brief history of the application of base-exchange water softeners to railways. 5-34. Disc.: 34-57.
Third Ordinary General Meeting held at the Institution of Mechanical Engineers, London, on Thursday 21 November 1946, at 5.30 p.m., Mr. F. Seymour Whalley, President of the Institution, occupying the chair.
The following precis is taken from Loco. Rly Carr. Wagon Rev., 1947, 53, 63-4: The Author began by pointing out that water is probably the most important raw material used an a railway, bath in essentiality and quantity, and before proceeding to the actual history of base-exchange softeners gave a condensed description af other forms of treatment.
Perhaps the earliest form of water treatment was the use of boiler compounds, which meant the treatment of feed water inside the boiler.
Lime soda softeners have been of great use. Today they produce better water and many refinements have led to plants being simpler to control, nevertheless they are not easy ta operate and full results are only obtained from them when they are controlled by chemists and/or engineers. This type af control is economically impossible an a 1,000 mile stretch of main line, with 30 or mare individual pumping stations, and 30 or more individual lime soda plants.
To ascertain the correct doses af each of the reagents used a chemical analysis of the raw water must be made, and where constant supplies of chemicals are not easily obtainable, an analysis of each of these must also be made. Nor is it sufficient ta take one raw water analysis. Many water supplies are drawn from surface sources such as rivers or ponds. The volume of water in these supplies varies with the seasons and with the rainfall. Sudden storms can change the mineral content of such waters completely in a few minutes. If this occurs and too little chemical is added to the water, the hardness is incompletely reduced, and if too much chemical is added, an objectional amount of the excess of chemical is left in the treated water.
Typical analysis of treated waters used for locomotive boiler feed on the LNER. gave final treated hardnesses varying from a minimum of 21 parts per million, as CaCO₈ to. 40 parts per million. These are excellent results and not generally achieved on other railways, especially overseas where the raw waters are generally worse and mare difficult to soften. Excellent though these results are, they fall short of the ideal results which were expressed by Sir William Stanier in his Presidential Address to the Institution in 1936, when he said "it has been proved that unless zero hardness is provided most of the advantage of water softening is lost."
Remaining hardness in water treated by lime soda softenmg plants has a greater importance than is immediately apparent. Some have been known to say that they like some hardness left in the water because the scale caused on the tubes thereby prevents corrosion. Mr. Turner exposed the flaw in this argument in his paper on "Corrosion of Boiler Tubes," read before the Institution when he stated that suoh coatings must be flaw-less (whioh is impossible), otherwise the corrosivity of the feed is concentrated where such covering is incomplete and mentioned the general rule, that to prevent corrosion, the water must be made so that it deposits no scale, and that the prevention of corrosion and the prevention of boiler scale formation are inseparable in practice. Nevertheless, from a boilermaker's point of view the amount of scale produced by such softened waters is so little as to make his repairs much. lighter than when crude water was used.
The Author's experience has been that reduction in boiler repairs, though important, is perhaps. one of the minor advantages of correct water treatment. Far more important is the abolition of washouts and the extra availability thereby obtained. As is also, from an operational point of view, the ability to run engines from one month's end ta another without a washout or a shed stoppage due to water conditions.
The Author then dealt with the matter of corrosion and summarised his observations by stating that corrosion in locomotive boilers can be controlled provided certain conditions are observed
1. There must be no lime or magnesia present in the boiler feed water, i.e.zero softening.
2. Provided that sufficient alkalinity is present to ensure that a hydrogen film is maintained, corrasion will not accur. With a base exchange softened water there is generally a high alkalinity present.
3. With highly saline waters, i.e. where the sodium chloride figure in the analysis is higher than the alkalinity, steel corrosion will occur unless tannin dosing is adopted.
4. Where copper fireboxes are concerned, together with copper tubes, and alkaline softened water is being used, it is necessary to use tannin to prevent copper corrasion. Particulars were given of the results of treating feed water an railways throughout the world. These are of great interest but considerations space render it impossible to .refer to more than two cases. A report showing the extraordinary results of installing" Permutit" base-exchange plant on the Chilean Nitrate Railways will be found in "The Locomotive" Vol. XXXVIII, Page 67. From this it will be seen that among other items a 30% fuel reduction on the heavy sections of the line was achieved and the general operation of the railway was so improved that the number of locomotives required to cover the service was reduced by no less than 25 % .
On the Southern Pacific Railway (U.S.A.) prior to treatment tubes were run for 90,000 miles and were then changed. After treatment tubes tubes ran for 350,000 miles. Previous to treatment firebox renewals per 100 engines were 14.1 %, after treatment 1 %. Washing out was previously done once every five days but was eliminated and water was changed every 30 days or Vide" The Locomotive" Vol. XLIV, Page 57..

Obituary. 58-9.
James Clayton; William Sydney Edwards and John Harold Ellison

Journal No. 196

Rudgard, H. (Paper No. 464)
Organisation and carrying-out of examinations and repairs of locomotives at running sheds in relationship to locomotive performance and availability. 64-123. Disc.: 124-59.
Fifth Ordinary General Meeting held at Institution of Mechanical Engineers, London, on Wednesday 15 January 1947, at 5.30 p.m., Mr. F. Seymour Whalley, President of the Institution, occupying the chair.
Included material one might not expect to have found: the self-weighing tenders introduced by LMS, self-cleaning smokeboxes, rocking grates and self-emptying ashpans (all with diagrams). Illustrations of pit with electric lighting and portable fluorescent lighting. Routine maintence included a standard examination. Cooling down was followed by cold water washing out. The problems of firebox cleaning and that of cleaning tubes and superheaters are considered at length. The system for handling locomotive casualties was examined. The incidence of hot bearings had been lessende by using "W" oil (85% high quality mineral and 15% rape). Data were presented for former LNWR 0-8-0 classes.

Stated that the manufacture of trimmings was very important. Kelbus portable weighing machines were employed to ensure that locomotives were correctly balanced. Apprentice training for fitters and boilersmiths, stores, and stock cards were also considered. Includes a rerproduction of what amounted to the LMS service manual which included when and how to assess Joy valve gear and routine mainentance of rotary bunkers and coal pushers.. Discussion by J.F.S. MacDonald (124-5) covered Indian experience; with the supply of stores and the lubrication of axleboxes where grease was advocated. G.A. Musgrave (125-6) noted the need for the provision of tools and good working conditions; W. Cyril Williams (126-7) noted the need to achieve maximum availability and advocated roller bearings; H. Holcroft (127-9)noted the inflexibility of reinforced concrete for engine shed construction; the transfer of old machine tools from the workshops to running depots as occurred on the SR; drop pits were useful for handling hot boxes and for spring changing, compressed air was better than steam for cleaning tubes as steam lances were difficult to maintain and the armoured hose was awkward to move, he applauded the self weighing tenders, the GWR employed its wheel lathes at ground level: it was simpler to turn the tyres whilst they were still on the locomotive; uneven wear of flanges on pony truck wheels (usually left-hand experience more); L.P. Parker (129-30) considered targets for stores, locomotive availability and piecework; W.N. Pellow (130) commented on cold water washing out, and the problems of handling the effluent and questionned the environmental impact of self-cleaning smokeboxes; A.W.J. Dymond (130-1) commented upon locomotive availability, periodical examinations and the statistical basis for some of the procedures;  M.A. Crane (131-2) commented upon availability and the influence of coal quality upon this.

Sir William Stanier (written communication, 132-3) noted that the organisation of the LMS motive power department differed somewhat from the organisation of the other railways, but the size of the undertaking justified to some extent the arrangements. The success of any organisation depends very much on the goodwill of those who have to administer it. On the LMS they were happy inasmuch as there was the closest collaboration between the motive power department and the chief mechanical engineer's department. But he suggested that the last paragraph on the first page of the Paper would be more correct if it were expressed somewhat as follows

It is the responsibility of the chief mechanical engineer to supply engines of the correct type to meet the requirements of the chief operating manager, and of the chief operating manager to allocate those engines so that the correct type of engine will be used to do the work required, and it is the superintendent of motive power's duty to see that these engines are maintained in good mechanical condition to work the trains, manned by well-trained and responsible enginemen at the time they are required.

When the Author refers to the method of washing out of boilers, he indicates that a pressure and quantity regulating valve is introduced between the hydrant pipe, etc., but he has not told us of the original difficulties experienced when it was found that the water pressure varied between wide limits at different sheds, and that the first essential was to ensure that the amount of water for cooling down the boiler was kept constant to ensure that a steady falling temperature was maintained. To do this it was found necessary to introduce a reducing valve between the hydrant and the control valve, so that the amount of water delivered for each position of the control valve was maintaind at a reasonably constant quantity. This is important when the cooling down of boilers working at high pressure is required.

As the late chief mechanical engineer of the LMS I would like to support wholeheartedly the excellent organisation under the "X" scheme and the standard mileage and periodical examinitions carried out by the motive power department, as I am sure It is largely due to that carefully planned organisation that the availability of the LMS engines is so good.

Under "hot bearings" the Author refers to. the importance of keeping dirt away from the journal. In my experience, provided sufficient oil is available, dirt does not in itself give a hot box but it does cut the journal and wear it away, and it is most desirable to provide means for keeping all dirt away from running surfaces, if possible.

I should like again to refer to the very happy relations that exist between the chief mechanical engineer's staff and the motive power superintendent's staff on the LMS and to re-assert the importance of correct personaliti,es to ensure the satisfactory working of any scheme.
Meeting at Derby on 23 January 1947
E.S. Cox (135-6) noted the importance of the inter-relationship between the CME's department and the running department and for the exchange of information. R.C. Bond (136-7) considered that X-ray examinations should be made. D.W. Sanford (137) considered that once the fire is thrown out locomotives should be moved as little as possible and noted that self-cleaning smokeboxes are detrimental to steaming. M.A. Henstock queried the value of periodic examinations and that there was a need to balance workshop versus motive power depot maintenance. G.F. Horne (138-9) stated that the X scheme reduced the number of repair cards received from drivers, he also considered that there was a need for larger tenders and the means for moving coal forward (Rudgard firmly rejected the need for larger tenders); R.E. Marks (139-40) advocated hard grease lubrication for use at low speeds; E.R. Brown (140) approved of the self-cleaning smokebox and rocking fire grate. Rudgard gave further data on engines stopped at sheds for 24 hours in response to an enquiry from R.C. Bond: this is tabulated

Rudgard's response (page 144) to E.R. Brown on electric lighting on steam locomotives showed the true reactionary nature of Rudgard: "It was very delightful and a great luxury" and having commented on the pilfering of the light bulbs closed with a firm "not a practical proposition"
Meeting at Newcastle-on-Tyne on 29 January 1947
R.A. Smeddle (144-5) was dubious about the LMS practice of stopping locomotives irrespective of the traffic department's requirements. I.V. Longley (145-6) was highly critical of pooling locomotives and argued that locomotives should be diagrammed so that they can return to their depots for intensive servicing (Rudgard responded that LMS locomotives were not pooled).

Journal No. 197

Spencer, B. (Paper No. 465).
The development of L.N.E.R. locomotive design, 1923-1941. 164-210. Disc. 210-43, 524-41. + 6 folding plates. 36 illus., 15 diagrs. (incl. 10 s. els.), 5 tables.
The Annual General Meeting and Ordinary Genera1 Mecting held at the Institution of Mechanical Engineers, London, on Wednesday 19 March 1947, at 5.30 p.ni:, Mr. F. Seymour Whalley, President occupying the chair. This paper was very widely abstracted: see brief account in Loco. Rly Carr. Wagon Rev., 1947, 53, 64..
Spencer began his paper with an examination of Gresley's conjugated valve gear: this included a folding diagram showing its application to a V2 class locomotive and a historical sketch of its development from its initial applcation to GNR O2 class 2-8-0 No. 461. Spencer made reference to both Holcroft's and Gresley's Patents for conjugated valve gears for three-cylinder locomotives. Figure 3 shows the Gresley form as an axiometric diagram. There also illustrations of the gear.
The paper is especially noteworthy in showing the how Gresley's design developed and includes many unfulfilled projects. It notes for instance that the sole Beyer Garratt was originally conceived on the basis of the GCR Robinson 2-cylinder 2-8-0 and that the design was modified to incorporate the O2 type chassis.
on pp. 206-7 Spencer summarised the fundamental desirability of three-cylinder drive: "the more nearly the variable crank effort of a reciprocating engine can be made to approach uniformity the greater will be the advantage derived for traction from a given adhesive weight. In this connection the superiority of the three-cylinder is apparent when the crank efforts of two, three and four-cylinder engines of equal cylinder volume are compared. Assuming an 8 to 1 ratio of connecting rod to crank and 75 per cent. cut-off, the greatest fluctuation with the three-cylinder engine is 10% from the mean, whereas with the two and four-cylinder engines it is 25%. and 16%. respectively. It is evident that if the tractive effort curve of the three-cylinder engine is lifted so that its maximum peak corresponds with that of the two-cylinder engine, an increase in mean tractive effort will be obtained with no greater tendency to slip. As maximum hauling power is one of the primary requirements of a locomotive, the fact that a three-cylinder engine is capable of exerting a considerably higher mean tractive effort than that of a two-cylinder engine with the same adhesive weight is of the greatest importance. A further advantage of the more uniform turning moment is the reduced shock and consequent reduced wear on the axleboxes and hornblocks.
Conjugated valve gear was fitted on all LNER three-cylinder piston valve engines built to Gres1ey's design. Whilst it can be urged that three independent sets of gear ensure a more accurate valv.e setting for the inside cylinder, the conjugated gear has the merit of simplicity and is not without advantages if due consideration is given to its inherent limitations.
The elimination of the third set of valve gear does not eliminate the work required to operate the third valve and it is essential that the outside gears should be of sufficiently rigid construction and provided with adequate bearing surfaces for the additional duty they have to perform. Furthermore, it is of the utmost importance that the fit of all pins should be to close limits. With the conjugated gear the effect of clearance on each of the six pin joints is cumulative and any clearance in the fixed fulcrum of the "2 to 1" lever and the floating fulcrum of  the "equal" lever is multiplied by three and by two respectively at the centre valve. Unit clearance at each of these eight points would consequently be multiplied by eleven at the centre valve. The cumulative effect of unit clearance at the seven, pin joints of each outside Wa1schaert valve gear is only approximately 3½ units, but the total amount of any such lost motion in the two outside gears will also be transmitted by the conjugated gear to the centre valve. It will be clear, therefore, that on both the primary and the conjugated valve gears, bearings of ample proportions manufactured to close tolerances are essential to successful performance; the most vital points being the fulcrums of the "2 to 1" and "equal" levers. In an endeavour to minimise the effect of wear, roller bearings were given an extensive trial but were not found satisfactory on those portions of the valve gear which had small angular movement.
In preparing the design for the original Pacific valve gear Gresley therefore decided to fit valves with 1% in. lap and to restrict the full gear cut-off to 65 per cent., with a maximum travel of 49/16 in., in order to minimise the possibility of overtravel on the valve of the centre cylinder. In actual practice the short lap valve gear made it necessary to run the ‘‘ Pacifics ” at comparatively late cut-offs and tbwards the end of 1924 consideration was given to the fitting of long lap gear to permit earlier cut-off working. The scheme was not proceeded with as it was not felt that the extensive alterations to the outside valve gear then proposed could be justifiec‘ in view of the successful performance of these engines on heavy main line duties. Early in 1925, however, the centre valve was given an additional 1/16 in. lap to counteract the effect of overtravel on the centre cylinder output at high speeds.
Following the exchange tests of April-May 1925, Gresley began to experiment with long lap valves on the Pacifics. The valve gear of engine No. 4477 Gay Crusader was modified and trials were carried out with valves having 1.5/8 in. lap. The results were most satisfactory in spite of the fact that only the minimum amount of alteration had been made to the existing valve gear. The success of this experiment led to the fitting of the completely redesigned outside valve gear originally proposed in 1924. The outside valves were given a lap of 1 5/8 in. with line and line exhaust and 1/8 in. lead, but the centre valve had an additional 1/16 in. lap in accordance with the practice instituted in 1925. Full gear cut-off continued to be restricted to 65 per cent., but the maximum valve travel was increased from 4.9/16 in. to 5.3/4 in. The first engine to be fitted with the new valve gear in 1927 was No.. 2 555 Centenary and in comparative trials with Pacifics having the original short lap gear the average coal consumption with trains of approximately 500 tons between Doncaster and King’s Cross was reduced from 50 to 38 lb. per train mile.
Gresley instigated a consiferable amount of work on poppet valves as developed by Lentz in both the oscillating and rotary cam forms, Comparitive trials were conducted between York and Newcastle in November/December 1929 using D49 class locomotives fitted with both forms of Lentz gear and a piston valve locomotive activated by Walschaers gear (Table 1). Later the first P2 2-8-2 No. 2001 Cock o' the North was fitted with rotary cam Lentz gear poppet valves, but this was unsuccessful.
Table 2 shows the comparative trials conducted on Pacifics Nos. 4473 and 2544 fitted with 180 and 220 psi boilers (and in the case of the latter smaller diameter cylinders). Table 3 showed the theoretical saving in horsepower achieved by streamlining...
He ended his paper by refering to the very promiing results which had been obtained from fitting the B3 class with Caprotti valve gear. Early experiments had shown a saving of 16% of coal when Nos. 6166 and 6168 had been modified in 1929. WW2 had interupted a further experiment with a modified form of Caprotti gear. The paper includes a wealth of detail: for instance on page 191 it is noted how its was a gift of a North American whistle from Captain Howey of the Romney, Hythe & Dymchurch Railway which led to the distinctive sound of the whistles fitted to the P2 and A4 classes.
Illustrative material: Figures: p. 164 Sir Nigel Gresley alongside No. 4498 Sir Nigel Gresley; 1 O2 class No. 461 (first three-cylinder design) 2 (folding plate fp. 164) conjugated valve gear for V2 class (elevation and plan); 3 Gresley valve gear; 4 No. 461 cylinders; 5 No. 461 valve gear; 6 K3 No. 1000; 7 O2 No. 477; 8 Gresley valve gear in front of cylnders; 9 A1 No. 4470; 10 P1 2-8-2 No. 2393; 11 U1 2-8-8-2 Garratt; 12 J38; 13 J39; 14 D49 with piston valves; 15 Gresley valve gear as arranged for behind cylinders; 16 D49 with oscillating cam valve gear; 17 D49 with rotary cam valve gear; 18 (folding plate facing page 176 shows layout of proposed six-cylinder geared locomotive based on modified D49 locomotive); 19 A3 class No. 2500; 20 steam collector (exterior); 21 steam collector (interior); 22 B17 4-6-0; 23 streamlined B17; 24 W1 in high pressure four-cylinder compound form, and 25 as rebuilt with A4 type front end; 26 V1 2-6-2T; 27 (p. 187) proposed 2-6-4T for suburban services with condensing gear; 28 (p. 188) proposed 2-6-4T for Great Eastern section; 29 (p. 189) proposed 2-8-2T for mineral working; 30 P2 No. 2001 Cock o' the North in original condition with poppet valves; 31 cylinder casting for No. 2001; 32 P2 No. 2002 Earl Marischal fitted with piston valves; ;33 smoke deflectors fitted to No. 2002; No. 2002 fitted with Bugatti A4-type front end; 35/36 (folding plates fp. 192) by-pass valves (including modified form) fitted to No. 2004 (text notes that carbonisation of the butterfly valves was a problem which was intended to reduce the strength of the exhaust and reduce fire lfting when starting); 37 A4 front end (front view); 38 A4 No. 2509 side view;  39 proposed 4-8-2; 40 establishing centre of gravity of A3 Pacific via a tilt test; 41 proposed articulated 2-6-4-4; V2 No. 4771; 43 proposed large 4-6-0 with taper boiler; 44 K4; 45 proposed 2-6-0 of 1924 (K3 boiler, but with smaller (5ft 2in coupled wheels); 46 V4 No. 3401; 47 proposed 2-6-4T with wide firebox; 48 Caprotti valve gear fitted B3; facing p. 532: valve gear for V4 class locomotives,

Discussion: Bulleid (211-12) commented on (1) balancing and how there had been a dispute between himself and the Doncaster Drawing Office over the calculating that of the original Pacifics, but that Dalby had verified Bulleid's calculations. Bulleid considered that over-runing of the inside cylinder was due to inadequate stiffness of the support for the fulcrum. He described K3 No. 1003 as "a very nice engine", and the first to demonstrate the advantage of high average speed on the level and uphill.  Bulleid partly spoiled the case for three-cylinder locomotives by stating that for goods engines the running men "given an equal tractive effort, had a weakness for a two-cylinder engine" as on adverse gradients with heavy loads that the "unequal turning" would enable a train to be started. [KPJ this appears to contradict the Glenfarg tests, but probably reflects his own observations on the demand for J39s on the LNER and the Q1 on the Southern].
Bulleid described testing P2 No. 2001 Cock o' the North on the test plant at Vitry. It is interesting that he always refered to the locomotive as "she" as in she compared favourably with the French engines in coal consumption per rail-h.p., and, better still, per d.b.h.p. When tested on the open road between Orleans and Tours "she" developed a very high horse-power of the order of 2,800, and was again shown to be an efficient engine from the point of view of coal consumed per d.b.h.p. In service, however, it was an extravagant engine as it was not properly used: instead of working trains well within its capacity over long runs, it was employed on a service such as Edinburgh to Dundee on trains much under its capacity; it stood for a long time at Dundee, went to Aberdeen and hung about there, and did a very poor mileage per day, with the result that it showed a heavy coal consumption, most of the coal being burnt through misuse rather than in working trains.
The P1 class engine was interesting, and he had always regarded her as the best-looking engine Gresley ever built. She worked trains of 100 loaded wagons from Peterborough to Ferme Park, and the real reason for her withdrawal from that class of work was that the train occupied three block sections and it was necessary to divide it at Ferme Park on a running main line before it could be disposed of.
Bulleid recorded the Bugatti connection for Gresley's streamlining: 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."
Spencer responded (page 222) on the performance of  No. 2001 Cock o' the North as originally built with poppet valve gear. There is no doubt that, had this engine been given loads commensurate with its tractive effort, the coal consumption per drawbar horsepower hour would not have been excessive. The P2 class engines were designed to maintain high average speeds with heavy loads and, before being sent to Scotland, engine No. 2001 demonstrated its ability for the fast uphill working on a test run with 650 tons behind the tender, between King's Cross and Grantham, when Stoke summit was passed at 56½ m.p.h. and an average of 59.3 m.p.h. was maintained up the 11 56½ miles from Essendine to that point.

E.S. Cox (212-14) remarked that if it was possible to do so without disrespect to the memory of a great locomotive engineer he would like to say that he had always thought that Sir Nigel Gresley's policy of applying the three-cylinder design to almost every type of locomotive was a little inconsistent. Where the power required was greater than could conveniently be provided by two cylinders, the three-cylinder arrangement was, of course, logical and suitable; but for medium and low powers it was very difficult to see what advantage could be expected from it. Mr. Bulleid had referred to the question of the turning moment, which had always been put forward as the principal advantage of the three-cylinder system, but which in practice and by common observation did not give any great advantage. So far as acceleration was concerned, he himself had never seen any test results to show that three cylinders could offer anything more than two, and so long as a percentage of reciprocating weights were balanced the three-cylinder engine was certainly not without a hammer-blow effect. On the L.M.S. they had a very modern design of medium-size three-cylinder 2-6-4 tank engine, and also a larger number of two-cylinder engines of exactly corresponding design. When those three-cylinder engines first came out their work was carefully examined, but under no heading was any advantage whatever found from the three-cylinder system of propulsion in an engine of that size, and all further construction had been with two cylinders.

Mr. Bulleid had referred to the balancing of the L.N.E.R. engines. They were balanced on rather an unusual principle. It was customary in balancing a three-cylinder engine to distribute the reciprocating values of the outside cylinders amongst the six coupled wheels, and the reciprocating values of the inside cylinder likewise amongst the six coupled wheels; but on the L.N.E.R. engines, whereas the normal practice was followed for the outside cylinders, it was the practice to balance the whole of the reciprocating values for the inside cylinder on the driving wheel only. That had the effect that, considering the driving axle by itself, the proportion of balance coming from the inside cylinder, being the total for that cylinder, rather outmatched the third of the outside-cylinder balance which was also assembled in the same wheels, so that there was the peculiar effect that during the rotation of the wheels the hammer-blow effect of the driving axle was working in an opposite direction to that of the leaders .and trailers. That was, in his opinion, one of the reasons for the peculiar clanking noises which had always been a feature of L.N.E.R. three-cylinder engines when moving about the track. He would like to ask the Author whether any ill effects had ever been found from that method of balancing, in the way ofe wear of crank-pins or bushes.

In reply Spencer (page 222) noted that whilst the two-cylinder engine may be cheaper in first cost and more accessible for maintenance, the three-cylinder engine has advantages which were considered desirable even in the smaller types. The more uniform smokebox draught action of the three-cylinder engine was found to react favourably on coal consumption and the lighter running gear could be more easily handled by the shed staff. He then turned to the unusual method of balancing adopted by Gresley. The practice of confining the whole of the inside cylinder reciprocating balance to the driving wheels has not resulted in any noticeable ill effects in connection with the wear of crank pins or bushes. With the distribution of reciprocating balance adopted on the Gresley "Pacifics" the axle hammer blow on the driving wheels is in the opposite direction to that of the leading and trailing wheels, and, as a consequence, the resultant whole engine hammer blow is greatly reduced. The hammer blows of the individual axles, however, are considerable and from the point of view of the bridge designer the division of the reciprocating balance equally between the coupled wheels would be preferable as far as the loading of cross girders and rail bearers is concerned.

Cox stated that rhe results quoted for piston valves v. poppet valves were very interesting. The LNER, of course, had very much greater experience than any other railway in this country with the poppet v. normal types of valve gear. He noticed that so far as dynamometer car tests were concerned, and comparing strictly like with like and modern engines with modern engines, the results obtained were much the same as were obtained on the L.M.S., namely, that under test conditions there seemed very little to choose between them in coal consumption. It was a pity that tests were not continued to obtain coal consumptions over a shopping period, so as to obtain data as to the steam-tightness of the pqppet valve; because he thought that it was there, rather than in any special efficiency when new, that the great advantage of the poppet valve might be expected to arise. He would like to know whether there was any information which the Author could give about relative maintence costs. In reply Spencer noted that comparative maintenance costs for the piston valve and poppet valve gear types of D49 class engines were not available, but LNER experience certainly shows that the poppet valve engines were the cheaper to maintain. There were D49 class engines then in service with the original cams and valves.

In reply to Cox's contribution concerning the NER (C7 class) three-cylinder "Atlantic" engines Nos. 727 and 2171 which had been re-built in 1931 and fitted with an articulated connection between the' engine and tender and had been fitted with a booster and new boiler of increased capacity to meet the additional demand placed by the booster Spencer recorded that the modifications were intended to increase the weight of trains hauled, particularly over the section between Edinburgh and Berwick, which includes the long gradient of 1 in 95 at Cockburnspath. The load hauled was limited by the ability to start on this gradient if a train was brought to a stand by a signal. In practice it was found that, with the heavier loads, there was a considerable drop in the speed of the trains up this gradient and as the booster could not be engaged until the speed had fallen to at least 27 m.p.h., it was too late then to make effective use of the booster and time was consequently lost which could not be regained. The riding of the converted engines was not good, due, no doubt, to the large amount of unsprung weight on the articulated bogie. When the boosters were removed and the engines ran in the articulated condition, the general opinion of the enginemen was that the riding was greatly improved, and was  superior to that of the original 4-4-2 type. But some difficulty was experienced under the existing shop repair system in having to lift and remove the tender from the engine, and it was also necessary to provide a carrying bogie to enable the tender to be moved about the works.

In reply (page 222) to the Cox contribution 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.

Bradley, W. (Paper No. 466)
What a running shed man looks for in a locomotive. 244-54. Disc.: 254-60.
Second Ordinary General Meeting of the Birmingham Centre held at the Midland Hotel, Derby, on Wednesday, 7 November 1945, at 7.30 pm.: chair taken by Mr. J. Rankin. "From the foregoing [a list of the many demands for versatlity, e.g. freight during week, passenger at weekends] it will be seen that apart from the special types of engines there is a big demand for a versatile engine of the mixed traffic type, of which we have an excellent example in the L.M.S. class 5 engine."

Journal No. 198

Greenwood, T., Fett, R.H., Hancock, C.W. and Gudgin, D.E. (Paper No. 467)
A general survey of the German locomotive industry during the War years, 1939-1945. 278-322. Disc.: 323-35; 541-7..
Section 1: Greenwood, T. The German industry's change to War production, the development of the "Kriegslokomotiv" and the training of apprentices.
Section 2:  Fett, R.H, Locomotive development and design. pp. 288-316.
Includes notes on the several exotic locomotives, notably the steam locomotive fitted with V-type engines (removed to United States) and a turbine locomotive.
Section 3. Hancock, C.W. The production of the "Kriegslokomotiv". pp. 316-20.
Section 4. Gudgin, D.E. Short cuts to production. pp. 320-2
Eighth Ordinary General Meeting held at Institution of Mechanical Engineers, London, on Wednesday, 14 May, 1947, at 5.30 p.m., F. Seymour Whalley, President occupying the Chair.
The President said that the Paper to be read that evening was based on the observations of an investigating team of eight members, drawn from the works of locomotive manufacturers, who had visited Germany, pooled their information, and arranged for the Paper to be presented in four sections, written respectively by Messrs. T. Greenwood, K.H. Fett; C.W. Hancock, and D.E. Gudgin. Mr. Fett  had been obliged at short notice to visit the U.S.A., was unable to be present, and his section of the Paper would be read by Hancock, the leader of the team.
Discussion by Sir William Stanier (323) who had been "interested that they also reverted to the round-top firebox; he thought they might have done much better if they had retained the Belpaire firebox when they got over the difficulty with transverse stays."..."Welding of coupling and connecting rods might have been all right during the war, but he would hesitate to use them unless they were heat-treated afterwards."

Hancock, J.S. (Paper No. 468).
Water softening for locomotive boilers. 336-41. Disc.: 341-51.
Meeting of th,e Indian and Eastern Centre held in Bombay on 19 April 1945, Mr. C.W. Twynam being in the chair.
Although presented in Bombay, the paper reflected LMS policy. "The LMS started serious water softening in 1931 when plants were ordered for 28 watering sations on the two main lines between London and Carlisle." Five firms shared the contract for lime-soda ash process plants. Problems with corrosion of steel boiler tubes and with priming led to the decision to fit continuous blowdown to all locomotives, and to extend softening to the bulk of water supplies. Copper corrosion was found in some shunting locomotives and tannin was added to prevent this. (Mileages) between boiler wash outs were increased from weekly to fortnightly, but had decreased from 2800 to 1500 miles when softening was introduced.

Journal No. 199

Moon, A.N. (Paper No. 469)
Welded carriage underframes on the L.M.S. Railway.  358-71. Disc.: 371-92.
Sixth Ordinary General Meeting held at Institution of Mechanical Engineers, London, on Wednesday 19 February 1947 at 5.30 p.m., Mr. Julian S. Tritton, President-nominate, occupying the chair. The Chairman apologised for the absence, due to illness, of the President.
Presented by G. Foster. Folding diagrams of: underframes for 48 foot bogie carriage (MR); 60 foot carriage (LMS); 57 foot composite vestibule coach; new lightweight coach; 3-car diesel unit; Wirral electric stock; and welded 57 foot corridor third brake. Cites paper by P.L. Henderson (J. Instn civ. Engrs., 1935-6, 3, 231 and Dearden and O'Neill Trans Inst. Welding, 1940, 3.  Discussion is interesting for contributions by Stanier (page 374) who related that Fairburn had suggested to him that if they could save a ton in weight of a vehicle it would be possible to save £10 a year on [electric] current, W.S. Graff-Baker (371-4) who took an almost energy accounting approach to railway vehicle construction and opting for carefully designed steel castings rather than fabricating individual components, L. Lynes (who described G.H. Pearson's contribution made at Swindon, and T. Henry Turner who described Gresley's contribution. Unfortunately, the author was prevented by illness from presenting the Paper and died before some of the meetings took place.

Fawcett, Brian (Paper No. 470)
The Westinghouse automatic empty and load brake with straight air control: its installation, operation and maintenance. 395-432. Disc.: 432-54.
First Ordinary General Meeting held at Institution of Mechanical Engineers, London, on Wednesday, 10  September 1947, at 5.30: p.m., Mr. Julian S. Tritton, President of the Institution, occupying the chair.
W.O. Skeat (438-9) noted that on the NER the reservoir had been located below the rear buffer bar on the tender without causing any problems. At Stratford on the GER the reservoir in effect formed an extension of the dragbox and was a massive casting. Mud doors were provided for cleaning the main reservoir.

Journal No. 200

Tritton, Julian S. Presidential address: "the challenge to steam". 462-98.
Fourth Ordinary General Meeting hcld at the Institution of Mechanical Engineers, London, on Wednesday, 17  December, 1947, at 5.30 p.m., Mr. Julian S. lritton, President occupying the chair.
Mainly diesel and traditional gas turbine, but also some observations (inclung diagrams) of coal-fuelled gas turbine (abrasion by fuel was a major problem). Table quotes operating costs for steam, diesel electric, oil and coal turbines. The following advantages were claimed for diesel traction:

1. Diesel-electric traction makes possible a dual purpose locomotive over a wider range of passenger and freight working.

2. Electrical braking on the locomotive is possible.

3. Elimination of service halts for water, coaling, cleaning fire, etc.

4. Elimination of ash disposal.

5. No smoke, resulting in cleaner train operation.

6. No sparks and, therefore, reduced fire hazard.

7. No reciprocating parts and, therefore no hammer blow, resulting in higher permissible axleload.

8. An even torque reduces wheel slipping to a minimum.

9. Diesel-electric locomotives of the double-bogie type offer a shorter rigid wheelbase.

10. Diesel-electric locomotives have a better power-weight ratio than steam locomotives. This ensures a higher proportion of pay load for a given train load.

11. For a comparable power-weight ratio diesel-electric locomotives give better acceleration making better timing schedules possible.

12. Shed periodical examinations of diesel-electric locomotives are not required so frequently as those of steam locomotives, nor do they take so long.

13. In the case of a diesel-electric locomotive, power is available almost immediately whereas the steam locomotive requires 4 to 6 hours for steaming up.

14. The diesel-electric locomotive can readily be arranged for multiple unit control.

The paper is also interesting for giving details of American proposals for coal-burning gas turbine locomotives developed by the American Locomotive Company and by Baldwin using Allis-Chalmers and Elliott gas turbines, respectively.T. Henry Turner (p. 497) gave the vote of thanks, and noted that the switch from steam to diesel traction in the USA was "awe-inspiring".

Lawrence, F.R.M. (Paper No. 471)
Recent German locomotive practice. 498-513. Disc. 513-23. 11 illus., 7 diagrs.
Second Ordinary General Meeting of Midlands Centre held at the Midland Hotel on Wednesday 24 April 1947 the Chair being taken by E. S. Cox.
The purpose was to present without criticism some aspects of locomotive practke on the Deutsches Reichsbahn which were largely unknown to British locomotive engimers because of the barriers imposed by WW2. The Author hopes that such comment and criticism as may be due will be brought out in the subsequent discussion.
The information was derived from the locomotive workshops at Stendal (Russian Zone) and Stahlwerke (near Brunswick), and from the Author's own footplate experiencrs on the Berlin L. of C.
Reichsbahn locomotives referred to in this Paper were:
01 class 4-6-2 express passenger.
41 class 2-8-2 mixed traffic
42 class 2-10-0 2-cylinder austerity freight.
43 class 2-10-0 2-cylinder freight (large boiler).
44 class 2-10-0 3-cylinder freight (large boiler).
50 class 2-10-0 2-cylinder freight small boiler
52 class 2-10-0 a-cylinder austerity freight.
No attempt was made to describe these engines in detail. Their design may be assumed to conform to British practice in most particulars other than those noted, such as feed water heaters fitted to the smokebox, the lubrication system for the motion and the use of the Krauss-Helmholtz truck.
Discussion: L. Abbott (516) commented on the lack of lead plugs in the fireboxes of German engines. Lead plugs were fitted for many reasons, e.g. (i) to prevent the boiler blowing up, in cases of doubtful maintenance of boiler fireboxes. (ii) To save the firebox becoming overheated, should the boiler become short of water, due to defective gauge frames and/or injectors. On the LMS it was the practice to change lead plugs every 7-9 weeks, and a thorough examination of the firebox and water speces, etc., was carried out at more frequent periods. In addition, the firebox, etc., was examined by a boiler inspector every six months. Lead plug failures were very rare and it was invariably found that when this did occur the primary cause had been due to shortage of water in the boiler. It would appear that if no lead plugs were fitted to the fireboxes of German engines, then the method of maintaining the water in the boiler and its correct registering was evidently very eifficient,
He was interested in the boiler and noted the tubes were welded into the tubeplates which would suggest that tube trouble was almost eliminated in Germany. If there were dirty boilers, the locomotives would be out of service a long time to have the tubes removed, dirt removed, and fitting and welding new tubes ino position. In his opinion this would be a costly practice as compared with the English method whereby tubes were rolled and beaded, and if they required changing, this operation could be quickly and efficiently carried out.
He referred to the tunnel in the tender for holding the fire irons and iasked how firemen could slide the fire irons from the firehole door into the tunnel without burning their hands.
The Reply (521-2) noted that not all German engines came out of the shops without lead plugs, but that many of the 52 class did not have lead plugs fitted. ‘They were, however, now in process of being fitted. Regarding tube welding, he agreed that every shed required skilled welders, but against that he pointed out that any form of tube leak could be stopped up with a run of weld without removing the tube. The actual removal of tubes did not often take place in running sheds; welding could go on until the engine was ready for shopping again.
With reference to fireirons, the tube underneath the tender was put directly in line with the firehole door, and once the fireman had pulled his irons out of the fire sufficiently for the handle to go inside the open end of the tender tube, all he had to do was to give a sharp pull and the irons shot back. It was not intended that the hot part should be touched by him. Asbestos gloves were always issued to all firemen before WW2.
R.G. Jarvis (519-20) said the Germans normally used the bar frame, and one of the main features of this type was that it lay along the cdntre line of the axleboxes. The normal German practice was for these frames to be made from slab, slotted out. Regarding horn stays, an almost ideal stay could be provided on bar frames as there was plenty of bearing area available for the stay to be attached to the frame itself and not to any separate axlebox guide which could itself become loose.
He referred to the tail rod bush on German built engines of older design. He believed that the normal method of dealing with wear of the bush was to turn it round three times during its life. In connection with the fabrication of motion parts, in Turkey during the war there was a good deal of difficulty in replacing connecting rods and sometimes the big end became damaged and was scrap. The Railway Administration could not afford to scrap the whole connecting rod, and, therefore, had to resort to the practice of cutting the end off the existing connecting rod and butt welding on a new big end. Apparently this repair was quite satisfactory its a war-time measure, and no trouble had been experienced