Harold Holcroft

Marshall notes that he was born in Wolverhampton in 1882 and died in Tadworth Surrey on 15 February 1973. As one of Churchward's brilliant young men in the heyday of Great Western locomotive development, Holcroft participated in the design of several of Churchward's locomotives, notably the 43XX 2-6-0. When the Churchward development programme tailed off he, like many other Swindon men, sought employment with a railway still in need of original design work. He joined Maunsell as assistant and participated in the latter's contributions to the SECR and Southern Railway's motive power. Whilst still with the GWR, he invented and patented a conjugated valve gear for three-cylinder locomotives; another form of this type of valve gear was also invented by Gresley. Holcroft in his Locomotive Adventure and other works was a highly significant contributor to the literature on the development of steam locomotives in Britain. He was also editor of Railway Engineering Abstracts (some of these abstracts were used for the later material in Steam Locomotive Development). There is a collection of Holcroft's papers at the NRM including the manuscript for a second autobiography: Life with Locos..

He was presented with an illuminated address by the Institution of Locomotive Engineers for his service as Journal Editor (J. Instn Loco. Engrs, 1932, 22, 238-9) portrait

An extensive biography was obtained from the Internet. Access to this has led to a very interesting correspondence from John Jeff, Harold Holcroft's grandson, which shows that like many locomotive engineers he also loved road vehicles and their engines.

David Andrews The role of the Chief Engineer in Backtrack, 2012, 26, 218 returns to Holcroft's Outline of Great Western locomotive practice for an assessment of Churchward as viewed via modern engineering management techniques


Three-cylinder locomotives. J, Instn Loco. Engrs,  1918, 8, 355-68. Discussion.: 368-95; 476-91. Paper 65

Four-cylinder locomotives. J, Instn Loco. Engrs,  1920, 10, 115-32; 139-64. Discussion.: 132-8; 165-77; 186-206.  (Paper No.80).

Steam heating of trains. J. Instn Loco. Engrs, 354-80. Discussion: 381-405. (Paper No. 195)

Some points of common interest in rolling stock and permanent way. J, Instn Loco. Engrs,  1929, 19, 249-84. Discussion.: 285-311; 823-30. (Paper No. 244)

The history of the Institution of Locomotive Engineers — the first forty years. J, Instn Loco. Engrs,  1960, 50, 662-82. 2 illus., table

Smoke deflectors for locomotives. J. Instn Loco. Engrs, 1941, 31, 462-89. Discussion: 490-509. (Paper No. 430).
Pp. 473-84 (17 illus.j : Includes an abstract of a National Physical Laboratory report by F.C. Johansen on experiments with models of the U and V classes: mainly the latter. Both the paper and the discussion range far beyond the U and V classes and considerable attention is paid both to the successful smoke-lifting propensities of the streamlined A4 Pacifics and their precursors, as well as to the height of the chimney (possibly why the GWR did not require smoke deflectors) , to the louvres fitted to the Jones locomotives on the Highland Railway, and to the predominant direction of travel (it is argued that strong head winds caused the greatest problem and that is why the London & South Western Section caused greater problems than the Brighton mainline). Holcroft cites both D.K. Clark and Colburn for references to capuchons. Many experimental designs adopted on the SR mainly for the King Arthur class are illustrated.

Locomotive trials on the Southern Railway. Engineer, 1925, 140, 658-62. 4 diagrs., 6 tables.
Comparative Yorkshire/Welsh coal tests, coincidentally giving very full details of N15 working.

Conjugated valve gears for locomotives: their history and development. Engineer, 1946, 181, 145-7; 168-70; 192-3.21 diagrs.
Reviews development of derived valve gear on the LNER.

Condensing by compression a locomotive experiment. Engineer, 1946, 182, 202-3; 227-9; 248-9. 3 illus., 3 diagrs., table.

Southern railway locomotive A816: a great engineering venture. J. Stephenson Loco. Soc., 1958, 34, 70-87. 12 diagrs.

Discussion on McDermid, The locomotive blast-pipe and chimney. J. Instn Loco. Engrs. 1933, 23, 162. (page 210)
H. Holcroft (210-12) noted damper dimensions and returning to Bazin's comments noted that three-cylinder locomotives should steam better than those with two cylinders (these comments are particularly interesting in view of what was about to happen/was happening on the LMS, where there was a terrible muddle in the early Stanier days). Three-cylinder engines gave a more continuous exhaust, reduced back-pressure and lowered fuel consumption. The kick in the exhaust at long cut-offs was absent Exhaust receivers had been fitted to the Armstrong singles; Churchward had experimented with a semi-chamber, but the value disappeared once a certain speed was reached. He also made observations on the accurate alignment of chimneys..

The Railways of Germany, I939-1945. H.M. Stationery Office.  see Locomotive Mag., 1949, 55, 128
This document was missed until spotted during work on the Lomotive Magaziine. British Intelligence Objectives Sub-Committee report, by H. Holcroft, covers civil, mechanical and electrical engineering in-so-far as they relate to practices extant on German railways. Much interesting material on locomotives and rolling stock is included, amongst this are general arrangement drawings of the standard "K50" war locomotive, the Krauss stayless boiler for the "K52" class and the" A.E.G." and "Stug" systems of coal dust firing. The whole forms a well-condensed survey of German practice during the period concerned.

Contributions to discussions

Fry, Lawford Some constructional details of a high-pressure locomotive. J. Instn Loco. Engrs, 1928, 18, 334

Marsh, G.C.  Recent developments in vacuum brake equipment. J. Instn Loco. Engrs., 1952, 42, 140-2 (Paper No. 510)
H. Holcroft (140-2.) drew attention to the statement “Churchward courageously introduced many new features such as engine driven vacuum pumps.” If the Author meant by that the ordinary direct-driven pump actuated by the crosshead that statement was incorrect, because the GWR had those pumps in use for seventy years or more on all engines, passenger, freight and shunting.
What Churchward did, which meant a big change in GWR policy, was to abolish the old sliding type of brake cylinder which moved on its anchored rod in favour of the fixed trunnion type. The original GWR cylinder was of some depth to obtain a large chamber capacity on one side and so avoid infringement of the Westinghouse brake patents which covered the use of a separate reservoir in conjunction with the brake cylinder. T.G. Clayton, on the Midland Railway, very ingeniously surmounted the difficulty in 1879 by the combined cylinder in which the reservoir surrounded the brake cylinder itself and was hung on trunnions, and that had been the type which Churchward adopted about 1903.
The Author later commented on the crosshead pump and said that these were gradually being taken off. In view of the very large number which had been in use on the GWR for a long period that was somewhat surprising, and it went to show that the pump was quite successful with a 25 in. vacuum, but with 21 in. or lower was less satisfactory, because a great deal of air had to enter through the relief valve to keep the vacuum down to 21 in. so leading to overheating the pump. Mr. Holcroft thought that that had much to do with the trouble, because he could not remember that when he had been on the GWR there had ever been any complaint.
The Southern Railway adopted crosshead pumps in conjunction with a 21 in. vacuum in 1925, to economise in steam consumed by the small ejector, but owing to various troubles- experienced they were eventually taken off some 10 years later.
With regard to the sliding ring type of cylinder shown in Fig. 6, when first introduced in 1881 the rubber band set up considerable friction, no less than 9 per cent. of the load on the piston being taken up in friction. The subsequent incorporation of graphite in the outer layer of the rubber reduced that to 3-4 per cent. It would be interesting to know whether that practice was still in use. Moreover, with the type of packing shown in Fig. 5 a special tool and a special technique had to be used to fasten the steel band which secured the rubber ring; otherwise the rubber puckered in places and caused leakage. It was necessary to have a very even pressure all the way round the steel band, and while the GWR had a tool for clipping the band, a good deal of experience and skill on the part of the operator were necessary in using it. In Fig. 7 the packing ring was clamped down by ’a retaining ring, and from the point of view of ease in assembling the cylinder that bas a great improvement, for with ordinary care anybody could insert the packing and its retaining ring and screw the bolts down.
On the question of freight trains, in this country there was still only a comparatively small amount of freight stock fitted with the vacuum brake. The difficulty with power brakes on freight stock, especially as far as this country was concerned, was not so much one of fitting as of maintenance and inspection. Goods wagons were out of the shops for nine or ten years, and their brake equipment was seldom subject to regular inopection. When one of these rover wagons got included in a vacuum-fitted train it might have a porous hose-pipe or a leaking neck-ring on the piston rod which would lead to brake failure in service. To avoid such failures it was necessary to install stationary brake testing facilities so that empty wagons could be tested in rakes before being loaded in goods stations and any defective wagon found set aside for repair.
More attention should be paid to the design of wagon equipment. The main train pipe should be butt welded to avoid joints and present a smooth interior and so made that it could be put into position as a unit, while the flexible hoses and rod packing should be of a nature which would enable them to stand up to long service without perishing. The use of synthetic materials might be investigated to this end.
With regard to the graduable type of steam brakc valve, referred to in the paragraph headed “ Locomotive Brakes,” when this first came out some were fitted on the Southern Railway, and there had been continual trouble with the breaking of the springs used in the hand control. It was apparently due to corrosion fatigue, and was definitely a weak point. Possibly some better spring material had now been found which overcame that trouble.
The automatic ejector system with the high vacuum reservoir maintaining the ordinary 21 in. on the train appeared to be very good on paper, but hk would like to know what happened when the steam pressure fell, as,-it did occasionally with bad coal, for instance, and the ejector could not maintain the high vacuum.
Direct admission valves were, of course, largely used nowadays, but, the Author had not said anything about the guard’s van valve and how it reacted to the admission valve. If there was automatic action of the guard’s brake setter one might get an accidental full brake application on the train instead of a service application. It would be interesting to know whether there had been any modifications and improvements in the van valves.
At one time a good deal of attention had been paid to the question of high speed brakes, where a brake power of something like 120 per cent. was applied on the train and gradually eased off as speed decreased, but that seemed to have receded today. Probably, traffic conditions being what they were, it was not possible to attain the high speeds which at one time were common or were anticipated.

H.V. Rawlings. Brake efficiency. J. Instn Loco. Engrs, 1920, 10, 554.

T. Robson. Counter pressure method of testing locomotives. J. Instn Loco. Engrs, 1943, 33, Paper 441 pp. 203-

Sanders, T.H. The evolution of railway suspension. J. Instn Loco. Engrs, 1935, 25, Paper 334 p. 212

Sanford, D.W. Development of the piston valve to improve steam distribution.. J. Instn Loco. Engrs, 1931, 21, Paper 273 p. 228
Holcraft underlined Churchward's advocacy for long travel piston valves in 1903 and shows how Maunsell followed this up.

Shields, T.H. The evolution of locomotive valve gears. J. Instn Loco. Engrs., 1943, 33, 368 (Paper No. 443)
H. Holcroft (448) said that a feature of all radial valve gears, and also of valve gears with a fixed quadrant link, was that they gave constant lead; i.e. the amount of opening at the beginning of the stroke remained constant, but the angle at which the valve opened, of course, advanced with the notching up. In the case of a shifting link eccentric gear such as the Stephenson or Allan straight link motion, however, not only did the angle of advance increase with the notching up but so too did the amount by which the valve was opened, i.e. they gave variable lead. That was a most valuable asset of the Stephenson gear, in that the valve was well open for early cut-offs at the beginning of the stroke; and an engine with a Stephenson gear, if it was well designed, would give a larger mean effective pressure and horse-power for the same size of cylinder than other forms of gear operating reciprocating valves. By reduction of lead in full gear it gave greater accelerating power from rest.
All valve gears which derived their motion from cranks or eccentrics or from crossheads connected to .cranks produced an approximation to harmonic motion, but it differed from the simple harmonic m that there were some minor harmonics compounded with it.
A simple harmonic motion could only be produced from cranks by gears having infinitely long rods, and in practical application the restricted length of rods and their angularities gave rise to minor harmonics of which those of any consequence were small in amplitude but of double the frequency of the main harmonic and at a phase. of 90° to it, and these octaves had the effect of introducing variations in the movement of the valve which might be beneficial or otherwise. The length of connecting rod was another factor entering into the case. The merit of a gear of any type depended on its mechanical layout and proportions. There had always been a great deal of controversy about which gear was the best from all points of view, but apart from mechanical considerations there was little to choose between the numerous designs described by the Author, because they all generated more or less the same type of harmonic motion, notwithstanding wide differences in the mechanism employed.
It was largely a question of the-survival of the fittest from the mechanical aspect, simplicity, cheapness of construction, adaptability and freedom from undue wear deciding the issue.

Topham, W.L. The running man's ideal locomotive. J. Instn Loco. Engrs., 1946, 36,  49-54.
A very long written contribution which summarises Holcroft's design philosophy


7859 25 November 1909 Improvements in or relating to valve gears for engines worked by fluid pressure. [derived gear for three-cylinder locomotives].


The Armstrongs of the Great Western. London: Railway World, 1953.
Originally listed as a Locomotive Publishing Co. publication. On pp. 28 and 29 John Gray is cited as "George" Gray. Appendix III A brief history of continuous brakes in Great Britain.
Brief subject-index of Addresses and papers read before the Institution and published in the Proceedings, 1911-1953. London: Institution of Locomotive Engineers. [1954]. 28pp.
Arranged under 60 headings which should be useful for anyone wishing to prepare a history of the steam locomotives. Acknowledges assistance of A.W. Manser on electric traction.
Locomotive adventure: fifty years with steam. London, Ian Allan, [1962]. 216 p. + front. + 34 plates (incl. 2 folding). 66 illus., 27 diagrs., (incl. 6 s. & f. els.), 4 tables, 2 plans.
Harry Holcroft's Locomotive Adventure is highly significant as it introduced a new type of railway literature in that it provided railway enthusiasts virtually for the first time an insider's view of how railways operated. In consequence, it probably allowed several others to commit details of their working lives to pen and paper. There had been earlier efforts of this ilk, but most had made their observations from a much lowlier position, such as the footplate, or engine shed. In the case of Holcroft he enabled the casual observer to enter into how railway engineers reached their decisions and how they reacted to failures, such as the derailment of the Maunsell 2-6-4T locomotives due to a mixture of poor track and probably over-optimistic locomotive design.
Locomotive adventure. v. 2. Running experiences. London, Ian Allan, 1965.  316 p. + front. + 16 plates. 37 illus., 36 diagrs., 104 tables.
Based on the author's notes made whilst observing SR locomotives from the footplate> Contents:

Author's Preface ... 7
The N Class ... 9
The K Tanks and the U Class ... 56
The El and DI Classes ... 79
Experiences with Wainwright Engines ... 140
Locomotives of the Constituent Companies ... 157
A Dissertation on Coal ... 171
Chapter VII Oil Fuel Firing
Derby (M.R.) System for Conversion from Coal to Oil Firing ... 180
Adoption on S.E. & C.R. 181
Adoption on Western Section 187
The 'King Arthurs' ... 196
A Pilgrimage ... 231
The General Strike ... 1926 243
The 'Nelsons' ... 248
'The Wrecker' ... 265
The EI/R and Z Classes ... 270
The 'Schools' Class ... 274
CHAPTER XV The Rail Bus ... 287
Buses as Feeders to Electrified Sections of Line
Construction of Steam Rail Bus by Sentinel-Cammell
Entry into Public Service on Dyke Branch
Inspection of Chassis at Makers' Works, Shrewsbury
Proposed Extension of Bus Services to Aldershot area
Run on Bus-Birmingham to Brighton via L.M.S.R. main line to Willesden Jet.
Run on Michelin Rail Bus, Bletchley to Oxford and back
Runs on Steam Cars in road traffic
Speed and Acceleration Tests, Brighton to Southwater and back
Test of Finished Bus in Steam at Makers' Works, Birmingham Transfer of Bus to Dunton Green-Westerham Branch
Trial Running on Dyke Branch and Shoreham-Horsham line
Withdrawal from Traffic
CHAPTER XVI In Germany, ... 1936 303
Institution of Locomotive Engineers Visit to German Railway Installations
Itinerary of Tour and Places visited ..
Observations on Attainment of High Speed
Run on Diesel-hydraulic Locomotive
Run on Main-line Electric Locomotive "
Run on Stream-lined Steam Locomotive No. 05.002
Special High Speed Trip at 100 m.p.h. Berlin to Hamburg and back
Index ... 313

Outline of Great Western Locomotive Practice, 1837-1947. London: Locomotive Publishing Co., 1957. 168pp.

Discussion on Whitcombe, H.A. The history of the steam tram. 327-79. Disc: 380-400. (Paper No. 369) J. Instn Loco. Engrs, 1927, 37,  384-
It has always seemed curious to me that when so much has been written about the steam railway locomotive so little attention has been paid by historians to the steam tramway locomotive. The subject has been generally neglected, and as one who looks back on the steam tram locomotive with affection, I am very glad that Dr. Whitcombe has come forward and given us such a very interesting description of this almost forgotten phase of locomotive engineering. It seems to me that much ingratitude has been shown towards a faithful and efficient, but now defunct, public servant, and that some belated acknowledgment is due to it. .

It may be difficult for the majority of members of the Institution, which has just celebrated its Silver Jubilee, to realise that less than 20 years before it was founded tramcars hauled by steam locomotives abounded in the cities and towns of this Country in the industrial areas. They were as usual a sight in the streets as the electric trams of to-day, and when properly maintained were quieter running. There was none of the droning of gears, whining of brushes, squealing of trolley and hum of overhead wires which so often distinguishes the electric tram in motion. The steam trams reigned in the industrial areas, but the more" genteel" communities of residential towns and cities in Victorian England would tolerate nothing less dignified than the sedately moving cars on the horse tramways, and much unmerited prejudice was shown towards steam trams. , What was it that caused the sudden landslide that swept away within a period of some five years horse trams and steam trams alike? The Author of the Paper attributes it to Press stunts in favour of electrification, and no doubt there is a certain amount of truth in that, but I think there was a more positive and compelling cause in the background. The idea was dawning just at that time that the municipal authorities should own all the public services within their boundaries. I think I am right in saying that the Tramways Act of 1870 gave the authorities in whose area the tramways ran the option of purchasing them after a period of 21 years operation, and it happened that the end of this period coincided with the awakening municipal consciousness. The introduction of lighting of the streets by electric arc lamps and the supply of current for lighting of business premises, so displacing the gas companies' lighting, was an opening which the more militant municipalities seized to the full. At first their power stations had slow speed steam engines, belt or rope driving small high speed generators feeding to the low voltage system needed for arc lighting. The plant stood idle during the day, until large storage batteries were added. Immensely rapid progress ensued, and in a very few years the old power plants were displaced by new ones in which high speed enclosed steam engines with forced lubrication were directly coupled to the generators. Improved distribution by means of the D.C. three-wire system gave voltages of 440 and 220, and so they were in a position to generate current both for power and lighting. It so happened that the option of taking over the tramways occurred to the authorities just at a time when they wanted to secure a large power load for the generating station during the daytime to improve the power factor and so bring the cost of current per unit to a low enough figure to attract new customers. The authorities therefore exercised their option in purchasing the tramways, and at the same time, of, course, they attained their object in running them under their own control. They took over the lines in their area, which were the most profitable sections, leaving any connections between the areas outside their boundaries in a more or less derelict state. These lines then fell into the hands of large power companies, who erected generating stations and linked the various tramways together by means of new extensions. or through running powers.

I think that this was really the main cause in sweeping away steam, horse and other tramways, although, of course, there was also a certain amount of pressure from the Press, which at that period began to regard anything of American origin as being in the van of progress.

My own recollections of steam trams begin with that great network of tramways mentioned by the Author, which extended from Birmingham in the east to Wolverhampton in the west, and from Walsall in the north to Stourbridge in the south, embracing the whole of the Black Country of South Staffordshire. Dudley was the meeting place of no less than four systems, and I remember, as a very small boy, looking down on the streets of that town from the castle walls and there getting my first glirppse, of the Dudley and Stourbridge Co.'s steam trams passing below. The engines were painted a pleasing shade of green with green and white cars, and were very attractive vehicles in contrast with the usual dull brown favoured by trams, and from that moment my interest in tramways was second only to enthusiasm for the railways. The next group of steam tramwavs with which I came in contact was in North Staffordshire, embracing Stoke-on-Trent, Hanley, and other towns in the Potteries; I am surprised that the Author has not mentioned that system, as it was a very extensive one.

My interest in horse trams was only a mild one, but of all the systems I saw, none impressed me more by their efficiency and smartness, both in their double-deck cars and their horses, than those which ran in the town of Northampton. This tramway was unusual in being of the 3ft. 6in. gauge in contrast to the 4ft. 8½in. gauge favoured by horse trams. There were other forms of power tramways than steam, but these were usually on small and isolated lines, except at Edinburgh, where there was a very extensive system of cable tramways. Such trams also ran between Birmingham and Handsworth, and one of the Birmingham lines had electric trams with storage batteries. These ran about 50 miles or so before the whole battery was taken off the car and replaced by a fully charged one.

The most unique collection of tramways was at Blackpool about the year 1895. Along the front was an electric tramway on the conduit system, probably the first of its kind. It ran very well in the ordinary way, but in stormy weather sand used to blow across the track and fill the conduit up to the slot, so bringing the service to a standstill. In the north of Blackpool there was one of the first overhead electric trolley lines. It began as a tramway through the streets, but became a light railway as it continued its way over the countryside to Fleetwood. The cars were single-deck vehicles, and, what is more, had electric heating, being very much in advance of their time.

Another system, between Blackpool and Lytham St. Anne's, was run by gas trams. An ordinary four-wheeled doubledeck car had a horizontal gas engine concealed below one of thc seats, the fly-wheel being located behind the panels below the windows. The driver would open a hinged panel, and with the assistance of the conductor pull round the spokes of the wheel to start the engine going, when the car literally " pulsed" with life. Transmission was by means of gears and a clutch. Compressed coal gas was stored under the car in a holder, which was recharged at one terminus.

There was one interesting feature about the rails on the Dudley and Wolverhampton Steam Tramway which I would like to. mention, and that was that they had the slot in the middle instead of at the side. This seemed to have some advantages, for the loading of the rails was symmetrical and wear was distributed across the whole width of rail-head, so that there was no unworn lip to stand up and become a danger to other road users. The wheels had the flanges in the centre. Colonel Kitson Clark has mentioned the heavy resistance set up between the flanges and grooves due to dirt, and I believe that the total resistance of tramway vehicles was as great at 22lbs. per ton.

Steam tramway locomotives were fired with coke. A good deal of the water was recovered by condensation, and tanks were filled at terminal points by means of a hose pipe and ground hydrant. After completing its number of trips, the tram would stop at a depot, where the engine was detached and replaced by another which had been refueled. In the yard of the depot the coke bunkers were refilled, water taken, ashes and clinker removed, oiling attended to, so that the engine was able to take up another turn of duty. There were also sheds for housing the cars at the depot.

The double-deck cars were rather top-heavy, especially on the 3ft. 6in. gauge, and it was not an uncommon occurrence for them to be blown over in stormy weather at exposed places. Unlike elcctric trams, they had no heavy motors and gear to lower the centre of gravity.

Holcroft, Harold

Joining Maunsell at the SECR. and staying with him to retirement was Harry Holcroft. He cuts an interesting figure amongst the team for he was an ideas man in 'What was by reputation a "play safe" design team. His enthusiasm for steam locomotives was evident throughout - he lived them. He was also well connected with engineers e.g. his family were friends of Armstrong, C.M.E. of the Great Western Railway.

He passed over public school "finishing" in order to take a premium apprenticeship at the Stafford Road GWR. works in Wolverhampton (managed by his uncle E.E. Lucy). He was placed in the assembly shop, with the millwrights and in the drawing office to get an all round feel for railway life. Soon he was generating ideas - his first patent was at the age of 18 (a vacuum brake auto disabler for shunter/goods engines). Ideas such as this drew him to the attention of Churchward and, after his apprenticeship, he was transferred to Swindon.

His self confidence and belief in his ideas was impressive and he clearly gave off an enthusiasm, and impressed the very people he needed to impress as an aspiring technical assistant, Churchward, Gresley and Maunsell of course and more - a veritable who's who of steam designers. He was used as a first technical assistant in the drawing office where he hatched his first plan for a 3-cylinder valve gear. Although Churchward had no 3-cylinder designs planned he recognised the value of Holcroft's work.

Holcroft was used to "beautify" Churchward's somewhat functional looking engines. He was also involved in development work on "The Great Bear" Pacific which eventually led to a research trip to the USA. He was impressed there by the development of the Mogul 2-6-0 wheel arrangement, and on his return he conveyed his enthusiasm to Churchward.

He was also involved in building works, running shed alterations /expansion; obviously an ideas man for all occasions. When Churchward declared himself content with his range of engines, things went a little flat at Swindon and so Holcroft responded to an advertisement in "The Engineer" posted by the SECR. He was hired.

Holcroft clearly enjoyed the freedom of Ashford which he did not have at Swindon. He was to modernise Ashford works and set about developing the power generating facilities. The coming war in 1914 put a block on these developments and, although he signed up to enlist, he fell ill. He spent part of the time while he was ill developing the 3 cylinder valve operation idea. Maunsell was impressed with this but not, it would seem, as much as Gresley who had read Holcroft's lectures on the subject.

Holcroft was invited to King's Cross and clearly enjoyed the experience but when Gresley tried to get him to move to the G.N.R. Holcroft didn't go behind Maunsell's back but invited Gresley to approach Maunsell himself. This was all part of Holcroft's hard work and fair play ethic which comes across strongly with a public school type of feel to it. He could have taken what was even then without the benefit of hindsight a dream move to work for Gresley but chose to do things "correctly".

Maunsell hit the roof with Gresley and the result was that Holcroft stayed at Ashford and, moreover, was given the go ahead to develop a 3 cylinder Mogul without any interference from Clayton, the Assistant Chief Mechanical Engineer, who was the restraining influence within the team. So the K1 and N1 were created.

It is Holcroft's relationship with Clayton which gives the best clues as to the way Maunsell's team worked especially after the Grouping. Clayton had a strong influence with Maunsell who valued him highly and Clayton (a Midland man) always stayed away from the controversial and untested, and warmed to people like Chief Draughtsman Jock Finlayson who was pushing for traditional Urie ways (which were reliable and proven). This was anathema to Holcroft who wanted to develop the locomotive and was always pushing his ideas with confidence as the way forward. Sometimes he got his way and sometimes he didn't which is probably about how things should be.

Holcroft was a locomotive man through and through but it wasn't the exclusive love of his life. He married and he was also extremely passionate about photography. This was probably enhanced by his next move. October 1923 saw him transferred to Waterloo with the Chief Mechanical Engineer and his staff, and he gained the title "Technical Advisor to the C.M.E.". This meant testing, evaluation and trials. He travelled extensively on the footplate and loved it. Most modern day enthusiasts would doubtless be jealous of this mans experience. He travelled on the footplate of every type of locomotive the Southern had and, very often, every one in the class on every bit of track.

By his own words, Holcroft was never happier than when on field trials in the company of engine men. He was responsible for things as diverse as locomotive numbering, the L1 rebuilds, 4 cylinder development (meeting Caprotti on more than one occasion to develop his theories), the use of 135 degrees 4 cylinder settings, naming of the N15X Class (L.B.S.C. Baltic tank rebuilds) and the rebuilding of E1Rs using N Class pony trucks as a trailing axle! The list actually goes on and on. Some ideas eventually saw the light of day like the W, N1 and U1 developments and others didn't e.g. a proposed 2-6-2 N Class adaptation and a double "Schools" drive adaptation to a Garret formation (!!!).

Holcroft was happiest pushing back the frontiers and one wonders if he may have prospered better with Gresley at the Great Northern Railway, after all Bulleid did well there. But then, hindsight tends to be an exact science. Holcroft had his say and Maunsell recognised his value and gave him his chances e.g. the steam heat companies trial, which was probably Holcroft's favourite task. This was a system to achieve full condensation of exhaust steam so boiler filling was minimal and heat was retained. Holcroft was able to contribute much to the system himself although he was supposed only to be evaluating it (typical of the man). On this subject I commend "Southern Experimental Steam" by Kevin Robertson. The photographs of N Class A816 are particularly intriguing.

When Maunsell retired, Holcroft and Lynes stayed on as Bulleid's technical assistants (locomotives and carriages respectively), but all the others left including Pearson, Clayton and Finlayson. Holcroft got on well with Bulleid but most of his time was taken up with the Railway's response to the war effort. He retired from the Southern in 1946 and then, for the next ten years, he worked for the Institute [sic] of Civil Engineers on railway periodicals. Holcroft died in 1973 at the age of 91 (85 incorrectly stated by Jessop)  having done as much as an one in the last generation of great steam innovators. Recognised by his contemporaries and valued by Maunsell, his boss of 25 years standing, he made a dynamic contribution to the C.M.E.'s team on the Southern.

Peter Jessop

Documents and memorabilia passed to the NRM by his grandson:

Letter 3rd January 1919, on Great Northern Railway headed paper, signed by HN Gresley,
arranging a meeting at King’s Cross on 9 January 1919 to discuss HH’s 3-cylinder valve gear.

HH’s Original Patent of 1909, no.7859, for “Improvements in or relating to valve gears for engines worked by fluid pressure”, plus Original 1909 ‘Provisional Specification’ of Patent 7859.
The model 3-cylinder 4-4-0 tender locomotive built by HH in 1917 to demonstrate his valve gear, and shown to Gresley at King’s Cross in January 1919, has been restored by, and is in the possession of, the Great Western Railway Museum at Didcot.

Three letters 1st, 4th, 16th April 1914, on SE & CR headed paper and all signed by REL Maunsell,
re. offer to HH of a position as Draughtsman in Locomotive Drawing Office, Ashford.

Letter 18th June 1920, on GWR headed paper, signed by Churchward,
re. Secretaryship of Institution of Mechanical Engineers.

Letter 17th February 1925, on SR headed paper, signed by Maunsell, re. salary increase to £400 p.a.
and four more ‘salary increase’ letters signed by Maunsell, dated 21/12/1928, 1/7/1931, 30/12/1933, 3/1/1936.

General Strike, May 1926 SR Directors’ Certificate, for loyalty to the Company, and for undertaking Special Duties during the General Strike.

Letter from Maunsell authorising additional £9 payment for special services during Strike.

Letter 23rd December 1926, handwritten by Maunsell on SR headed paper,
acknowledging his satisfaction with HH’s work, and appointing him “Assistant to the CME”.
Also draft reply from HH.

Letter 2nd February 1939, signed by OV Bullied, on SR headed paper,
re. appointment to Technical Assistant (Locomotives), and salary increase from £560 to £650pa.

Letter 6th August 1943 from Secretary of Railway Research Service (affiliated to War Office),
thanking HH for “sending important data on Italian State Railways in the nick of time”, and for which they had “been searching everywhere for several months. This information is already on loan to the War Office, and….photostats will be in Washington and North Africa...”

Letter 25th April 1945 from Bullied, acknowledging HH’s wish to retire.

Letter 9th January 1956, from KJ Cook, President of The Institution of Locomotive Engineers,
regretting HH’s decision to retire from the Council, and acknowledging “the enormous amount of work you have done for the Institution since its foundation.”

Large Scrap-Book of Institution of Locomotive Engineers Summer Meeting in Germany, 1936. Souvenir photographs and pictures, with narrative of the trip by HH.
Enamelled lapel badge, inscribed “Institution of Locomotive Engineers, 1936, GERMANY” and bearing the Union Flag crossed with the Swastika Flag.

Enamelled lapel badge of The Institution of Locomotive Engineers “Fifty Years”.

Two enamelled lapel badges of The Newcomen Society.

HH’s small brass & enamelled lapel badge “Railway Service S.R.” No. 506

Rule Book 11/11/1914 of the Association of Railway Locomotive Engineers of GB & I.

GWR Swindon Examination Certificate (on card) to HH in 1912, for passing in “Rules and Regulations affecting the safe working of Railways and the appliances used in connection therewith”

Unpublished Manuscript of HH’s book Life with Locos (63,000 words, no illustrations):
NRM now holds publishing rights to this MS.

Letter 22nd July 1953 from WA Stanier, thanking HH for sending his “ most interesting book The Armstrongs of the Great Western”, and reminiscing about his father and Dean.

Correspondence (22 letters) from OV Bullied, between Dec. 1952 and Feb 1970.

John Jeff

John Jeff has corresponded with KPJ by e-mail concerning his life spent with his grandfather, Harold Holcroft, and the placement of Holcroft's documents, etc at the NRM and at the Great Western Society's Museum at Didcot.

In response to KPJ's observation that HH's contribution to the literature had a great sense of personality, John Jeff wrote;" He really was the gentlest and most modest of gentlemen. I was fortunate enough to share his home for 19 years, after my parents and I returned from India in 1945. I remember, as a boy of about 9 in 1947 (I think), the table in the bay window in his sitting-room was turned into a draughtsman’s desk as he produced drawings for a scaled-down “Schools” loco for the Romney, Hythe & Dymchurch Railway, at their request, but not taken up by them in the end (lack of funds, I believe). He discouraged me from taking any interest in a career in railways, with the ‘end of steam’ in sight, but was always ready to help or advise on anything to do with my motorcycles!

He had a couple of really old motorcycle engines, and a Stanley Steamcar engine, in his workshop. The Steamcar engine went to the Science Museum before he died, and I passed on the motorcyle engines to an enthusiast some years after HH’s death; the older of the two engines (together with tank, carb, cables, magneto) turned out to be home-made in 1903 (I found his 1904 Driving Licence in a small compartment in the petrol tank), probably by HH himself, and is now a magnificent completely restored working motorcycle, registered with the VMCC as “The Holcroft”, and the oldest working motorcycle in the Sammy Miller Museum at New Milton, Hampshire. Sammy Miller was my hero, and it was a great thrill to be shown round his museum by the Great Man himself when the bike had been restored.

After HH died in 1973, a representative of the GW Society at Didcot (a Mr Little) visited us and was encouraged to remove any papers of Grandfather's that the Society might like to have. Although HH was meticulous in keeping a detailed record of everything he donated to Libraries, Museums, etc.(I've still got his handwritten lists), I'm afraid Mother and I weren't so meticulous, so there could possibly have been the drawings for the RH&D amongst the papers that the GWS took - there certainly were some rolled-up drawings that went that day.

His Certificate of Apprenticeship and a Testimonial, both, I think, signed by Churchward, are/were framed and hang/hung for diners to enjoy in one of the preserved Saloon Cars at Didcot.

Incidentally, HH was such a 'GW man' that his Wolseley 12/6 car, which he kept from 1932 until it went to a car collection in 1965 or 1966, had the Reg. No. GW 8137 (any 'loco' significance in the 8137?), and no doubt still exists somewhere.

I enjoyed and much appreciated Peter Jessop's biography of my late grandfather, Harold Holcroft. Just one minor alteration, please, in the final paragraph - he died aged 91, not 85. Delighted to say that the illuminated address which is mentioned, presented to him by the I.L.E.in 1931, and signed by 13 Past Presidents, still exists, and hangs proudly in my hallway.

I have just returned from York, where I handed over to the NRM the final 'bundle' of his papers, memorabilia, and unpublished manuscript of his second autobiography "Life with Locos". Amongst those documents was the original Patent 8759 of 25 Nov 1909 (3-cyl valve gear), and the letter of 3 Jan 1919 from Gresley inviting HH to meet him at Kings Cross. Incidentally, the model locomotive that HH made to demonstrate his valve gear and which he took to that meeting is in the possession of, and has been restored by, the GWS Museum at Didcot.

Among the papers were numerous copies of articles relating to the conjugated valve gear, and I was particularly delighted to be shown the contents of two boxes of his notes, notebooks and drawings already in the Archives at the NRM.

In a belated bid to go paperless Kevin has been going through a mountain of photocopies, print-outs and grey documents in his loft and sometimes finds things of interest and drops them into steamindex. The following was received from J.A. Jeff, Holcroft's grandson and is of interest.

Dear Kevin,
BINGO! Towards the end of the unpublished "Life with Locos" (which HH wrote in his 90th year!), I have found the story of the RH&DR loco he designed - but it wasn't a "Schools". Even though I have passed the publishing rights of the book to the NRM, I'm sure they won't mind if I quote from it:
"Early in 1946 the Directors of the 15in. gauge Romney, Hythe & Dymchurch Railway, anticipating heavier traffic in the near future, needed a more powerful locomotive than those in use. They were looking for an experienced designer who had the time available, and the enthusiasm to carry out, the preparation of working drawings. Holder, the Manager of the RH&DR, approached me to see if I would be sufficiently interested in carrying out the design. He explained that his Company would not be able to afford either to engage a salaried engineer or to pay a fee to a consulting engineer commensurate with the work involved. It would have to be taken on voluntarily, the reward being the kudos attached to the production of a new locomotive. The task appealed to me very much, because it enabled me not only to keep my hand in with locomotive design, but also to develop new and somewhat radical ideas latent and awaiting an opening. On 26 March 1946 holder met me at Ashford Station and took me to his house in Littlestone for a preliminary discussion; then to the Works at New Romney, where I saw locomotives and rolling stock and obtained some basic data, such as tyre profiles, loading gauge, minimum curvature and maximum wheel loads, etc. Then we went over to meet Capt. Howey, the Chairman, and have lunch at his house.
In the discussion which followed, it seemed that they wanted a mixed traffic engine of greater power than their present locomotives, in order to deal with heavy excursion trains chartered by holiday camps, to do away with double-heading of such trains. Also they wanted to develop their transport of beach shingle from the Dungeness area by conveying it over temporary tracks to reach out for supplies beyond points to which no wheeled road vehicle could penetrate. The scheme was to convey truck loads of shingle to staging at New Romney, so that their loads could be shot into waiting lorries. It would provide some revenue in winter months when there was little or no passenger traffic. Having heard all the requirements, I suggested that a 2-8-2 type would suit the circumstances best. My host asked for two outside cylinders only and for the design to be as simple and as straightforward as possible. Capt Howey then ran me over to catch the 4.15pm non-stop ex Folkestone Central. He was a former racing driver, and took the tricky Marsh roads at 80mph in his Lagonda. The combination of man with machine was so perfect that I felt no qualms.
To save time I made a start on the design, but it was not until 23 May that a letter of approval camewith the official instruction to proceed with the drawings. The delay, it seems, was due to Goddard, a Director, wanting a 4-8-2 type instead of 2-8-2. By 10 June it was pssible to submit an outline diagram showing what the locomotive would look like, and this was followed by a visit to New Romney on 15th. Howey & Holder were at Ashford to meet me; they had also come to see Goddard pass through on the footplate of the Golden Arrow boat train. Howey dropped us in Hythe and went on to collect Goddard at Dover. Meanwhile Holder took me by train to New Romney; it seemed such a Lilliputian affair, and yet the locomotives were as perfect as those of full size and almost as costly to build, the difference being due to the smaller quantity of metal required. The engine on this occasion was a replica in miniature of a Gresley Pacific, but had only two cylinders instead of three. The driver was Crittall, head of the well-known firm of metal window-frame manufacturers. When seated in the one-a-side compartment it seemed to be reminiscent of 'Alice in Wonderland'. However, the coach rode well; the track was far superior to that of the Lynton & Barnstaple Railway. At New Romney, Howey & Goddard joined us and we had some further discussion on the 2-8-2, and at the shops with Fitter Leslie. The upshot of this was that they wished to have a model made to give them a better perspective than that conveyed by the plane view of an outline drawing. Accordingly, I was instructed to visit Hambling, the Model Maker, and arrange for a model to be constructed in accordance with the line diagram. This model was duly submitted to the Directors; later it was to be seen in the Museum at New Romney Station.
On 26 July 1946 I was requested to visit the offices of the Victor Engineering Works at Rainham, Essea, to discuss the prospect of having the locomotive built there. From this visit it was evident that the boiler would have to be made by a specialist firm of boilermakers, and it would be necessary to obtain steel castings, ball and roller bearings and certain fitments from specialist firms. Otherwise the Works had the plant and staff to do the job; however, nothing came of it. My production of the details drawings continued through 1946 and into 1947, being completed by March. On 27th of that month I was asked to visit the works in Hove, where the job of overhauling some of the existing RH&DR locomotives was carried out after the run-down condition under which they were handed back by the Military after completing 'Pluto', the petrol pipeline from across the country and extending from Dungeness to the French coast. In the works was the last one to be done, 'Samson', nearing a finish. My visit was to discuss the practicability of the firm building the 2-8-2 design, and their principals whom I met expressed their willingness to go ahead with it. Accordingly on 9 April 1947 I called in at Hove with a complete set of working drawings, and went through them in detail with the management, who after they had looked further into costs would submit their price for construction of the new locomotive. It was about this time that the firm sent in their account for the general repairs of the existing locomotives in their shops. The account came as a shock to the Board of the RH&DR, and I was asked by them to act as an arbiter on their behalf, but I refused saying that it was not in my line of business and that what they needed was a cost accountant. What the directors had not realised was the steep and rapid rise in price of materials and wages in the post-war period. Had they decided to go ahead with the 2-8-2 at once, much time and cost would have been saved. As it was, there was some shilly-shallying in the early stages and until I had full assurance that my design would be accepted in toto, it was no use embarking on the production of finished drawings. As things turned out, it was evident that they could not find the money for a new locomotive after meeting the bill for repairs.
A year later Capt Howey asked if I would design a 4-8-4 multi-cylinder engine for him. It seemed illogical to incur the greater expense of the building of a larger and multi-cylinder locomotive if they could not afford the simple 2-8-2. However, I outlined something for him though never expecting that the locomotive visualised would ever be built, unless some 'fairy godfather' put down the hard cash. He invited me to lunch to discuss the design, but my visit made me realise that it would be a waste of time and effort to do any more, and I declined to proceed any further. The Captain drove me to Sandling Junction for a train, but made no further reference to the object of my visit. He seemed quite oblivious of the vast amount of work put into the creation of a complete set of working drawings for the 2-8-2; just as many as for a full-size locomotive. At no time did I receive any formal thanks from the RH&DR. Steam locomotive enthusiasts are prone to day-dreaming, and are to be forgiven for lapses of Obligations for services rendered.
The Institution of Locomotive Engineers elected me to serve a term as Vice-President for the Session 1946-47. As the President had to make some visits Overseas during that period I was called upon to deputise for him severaltimes. Meetings were held in the hall of the 'Mechanicals', so I conducted them while occupying the famous Stephenson Chair." A few pages further is a pleasant little anecdote:
"Under Nationalisation, the Association of Railway Locomotive Engineers (ARLE) became redundant, and its functions were taken over by the Headquarters at Marylebone (sometimes referred to as 'The Kremlin'). My admission to the ARLE came when Clayton's retirement caused a vacancy in the Southern Railway's representation, to which I was nominated. At the next Meeting of the Association I was at hand and was in due course called in for the formal ceremony of induction. It fell to Gresley's lot to perform this, and by the paternal way in which he drew me forward for presentation to the Meeting my feelings were that he was glad to do so. Was he too remembering the historic occasion of our first meeting at his Kings Cross office, when we planned the three-cylinder set-up and its valve gear that was applied to his locomotive construction for the rest of his days? After the affairs of the Association had been wound up it was found that there was a good balance remaining. What was to be done with it? A majority was in favour of a week-end at Gleneagles, so on the evening of Friday 24 June 1949 members assembled at Euston, where a special train of sleeping cars and a 'diner' was drawn up to take them. Gleneagles was reached at breakfast time, and after this many of the members went to play golf (referred to by the men in the 'shops' as "b ..... marbles played with walking sticks" !!). The farewell dinner party ended up with speeches of a valedictory character. I sat beside Bullied; he had his brother-in-law HG Ivatt on the other side."
Another little story recalls a 'red-letter' day for him on 15 June 1956 (he was by then 74): "The Council of the Institution of Locomotive Engineers were holding their customary luncheon, with the retiring President for the past Session, KJ Cook, as their guest. Having attended Council Meetings over 37 years I thought it was my turn to retire and give place to a younger man, and so tendered my resignation. It was propsed that on this special occasion my name should be coupled with that of the ex-President as joint guests, with his concurrence, and it was agreed to. When the time came for drinking my health I received a standing ovation by the company, which included six Past-Presidents, Stanier, Bullied, Williams, Allcock, Collingwood and Cook, besides Vice-Presidents and ordinary Members of Council. It was quite overwhelming to be honoured by such an assembly of the 'top brass' from the locomotive profession. " There is, of course, lots more. When the RH&DR "failed" him, he turned to the model engineers, and explains in the book the design of a 1/16th size 'Super-Schools', an advancement of the V Class. He sums up the two pages of detail by saying "The performance of the engine on the track under load was all that one could wish for. It steamed very freely." The detail, sadly, means nothing to me, but no doubt one day someone else will enjoy reading the 'technicalities

Updated 14-07-2020

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