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The New Zealand Railways Magazine, Volume 2, Issue 5 (September 1, 1927)


I Was much interested in the statement in your London Letter that the locomotive “Gladstone” was to be preserved in the South Kensington Museum.

When a pupil of Mr. Stroudley, I was engaged both in the design and trials of the “Devonshire,” the experimental engine of this class-the “Gladstone” following some three years later on slightly enlarged lines.

The history of the development of the type is interesting.

From a free-hand drawing by Professor: Scott.)

From a free-hand drawing by Professor: Scott.)

On William Stroudley coming from the Highland to the Brighton and South Coast Railway he found the locomotive stock at a low ebb. His first work was to rebuild six six-wheeled double framed Craven engines, 17 in. by 24 in. cylinders, 6 ft. 6 in. driving wheels (four coupled behind), with larger boilers and roomy cabs.

These engines for many years did the bulk of the main line express work.

Then came the “Grosvenor” (a single engine), some smaller single engines, and goods and tank engines from his own designs.

A demand then arose for an express goods engine to run the “Grand Vitesse” and Continental fruit traffic, and the “Lyons” class locomotives were built. These were six wheeled single frame engines, with four cylinders 17 in. by 24 in., 5 ft. 6 in. driving wheels (four coupled in front), and about 1,000 square feet of heating surface, with 18 ft. grate area. The weight of these engines loaded was about 33 tons each.

They proved so satisfactory that they soon found their way into the heavy fast passenger and excursion traffic and the express traffic on the Portsmouth direct line, a very hilly road.

Mr. Stroudley then determined to build a new class of express engine of this type, and drawings were got out from which the “Devonshire,”“Cornwall,” “Beaconsfield” and others were built.

In these engines the driving wheels were 6 ft.7 1/2 in. in diameter (four coupled in front), the trailing wheels 4 ft. 6 in., the cylinders 17 1/4 in. by 26 in., the heating surface was about 1,200 square feet, and the grate area about 22 square feet.

The weight of each engine was 35 tons in running trim.

That this comparatively small weight was, in fact, the “motive” of the design, I had the good fortune to have expounded to me by the Chief himself.

Pupils were occasionally invited to dine at Preston Park. One night when I was the only guest sitting in the billiard room after dinner, I, greatly daring, asked Mr. Stroudley why he adopted a design of engine, which most people-at that time-thought to be extremely risky, instead of the more conventional arrangement with leading bogic.

His answer was:-

Locomotives now-a-days are built far too heavy for the power they develop; they are simply fitter's engines-they should be fitter's engines, driver's engines, and above all, engineer's engines. Gooch built broad gauge (7 ft.) express engines in 1851, weighing only 35 tons, and indicating 1,000 h. p. and they are still running the fastest trains in the world. We should at least be able to obtain 25 i. h. p. per ton of engine, but to do this we must utilise the major portion of the weight of the engine for adhesion. We cannot affect the weight of the bogie and must have leading weight. The centre of gravity must, therefore, be kept well forward and the engine will run the steadier page 5 for it. So the leading wheels must be coupled to the drivers. My engines are, in fact, four wheeled four coupled machines, with a pair of trailing wheels added to ensure steadiness; further, the high pitched boiler necessitated by this arrangement of wheels conduces to steadiness. With a high centre of gravity the engine will roll on its springs; with a low centre of gravity it will box and tend to destroy itself and the track.

How correct Mr. Stroudley's argument was has been shown by the remarkable performance of this class of locomotive. It has never been excelled.

The length of this letter precludes my dealing with the many features which helped to bring about a smallness of fuel consumption unapproached to-day, and a freedom from repairs which permitted engines to remain on the road from three to five years without visiting the workshops. I may add, however, that we still have in use here the perforated damper and lubrication of wheel flanges imported directly from Brighton.