bart. Sir Arthur Percival Heywood

“ Owing to the increasing number of experiments, and to other calls upon my time, assistance eventually became necessary, and, though I am still conceited enough to keep the more delicate manipulations in my own hands, so far as I can find time to execute them, it has gradually come about that I have seven or eight artisans in the little workshops. Practical acquaintance with every detail both in survey, design, and construction of narrow-gauge railways has given me something of a pull over the professional engineer. ”

“ It must be understood that I do not here attempt to enter upon the comparative merits of narrow gauge railways generally, but merely to give particulars of what has come within my own experience. To facilitate a comprehension of the conditions under which I have worked, it will be well to explain that I make no pretension to be considered a professional engineer, and that I speak rather as a self-taught mechanic and surveyor. ”

“ As a case in point, and doubtless there are plenty of others, a quarry owner of my acquaintance is at the present time conveying some 80,000 tons of stone annually by means of traction-engines from his works to the railway along 21⁄2 miles of highway. The road authorities, levying £400 a year for extraordinary traffic, are utterly incapable of coping with the destructive action of the heavy loads, and the roads are in a state of disintegration that baffles description. ”

“ Material of any kind can be as effectively delivered on ship-board by narrow gauge railway wagons as by horses and carts, if not better. In reckoning up the cost of transhipment from small wagons on to a railway system—no great matter with proper appliances—it must not be lost sight of that, even if a branch of standard gauge were constructed to many establishments, the large wagons cannot, as a rule, be got up to the point where the material lies, and a preliminary transference in barrows or carts is necessary. ”

“ Now it is clear that, unless there is a prospect of large increase in the traffic, it would be absurd to employ for a maximum of 10,000 tons a railway equal to 60,000 tons, and so the question arises:—What is the smallest and therefore the cheapest railway capable of being practically and advantageously worked? ”

“ The speed on small lines is not generally a matter of much moment, owing to their usually moderate length. A locomotive that is sufficiently powerful to start a given load, will without difficulty get it along at from 8 to 10 miles an hour. It has occurred to me that a very fair approximation to the reasonable running speed of which any gauge is capable is to be found in estimating that the speed of passenger trains is equal to as many miles per hour as the gauge is inches wide, and, for goods trains, to half that amount. ”

“ A wheel rests upon a rail on one point, or possibly on a transverse line of which the length is equal to the width of the rail. With a small insistent weight the molecules of the wheel and rail interlock without injury, and adhesion, on the principle of an infinitesimal rack and pinion, is the result. As the weight is increased on the fine bearing area, the molecules become disturbed, and fail to offer so firm a fulcrum. Ultimately they become displaced, and move as rollers between the two surfaces, materially reducing the adhesion. ”

“ In concluding these comparisons, in which it may be thought that the railway is shown in a less attractive light than might have been expected from an enthusiast, I may explain that I am no advocate of ill considered schemes, planned without proper knowledge, cheaply constructed, and carelessly worked. ”

“ It is not advisable to attempt to spring a 14 lb. rail round a sharper curve than five chains, or an 18 lb. rail beyond ten chains radius.
The result of attempting too much springing is that the rails, under the traffic and changes of temperature, work outwards at the joints and make “dog legs” more or less serious. Where the ballast is of a loose dry nature very little, if anything, can be done with springing. I have enlarged upon this subject of rail-laying because it is of prime importance to a good road, and a matter that, on narrow-gauge lines, does not receive the attention it requires. ”

“ The fact that narrow gauge locomotives are usually required to surmount much steeper gradients than are generally to be found on standard railways, makes adhesion a question of the first importance. It is very generally supposed that the co-efficient of adhesion between a wheel and a rail is a constant fraction of the insistent weight, varying slightly with the molecular structure of the metals in contact. ”

“ For short distances, where the emptying bears a greater proportional relation to the running time, or where the load must be got rid of in a particularly short space of time, tip-wagons may answer. For such purposes as my experience has had to deal with, they are a drawback, which, as I have previously pointed out, is increased by their inadaptability to the carriage of bulky goods. One of my strong contentions is that, on a small line, to avoid expense in rolling stock, every vehicle should be available for every purpose. ”

“ I go so far as to think that, without getting rid of a depending fire-box, no really satisfactory tank engine can be constructed for a small gauge railway unless idle wheels are introduced, a proceeding that cannot too strongly be deprecated. ”

“ The diminution of the power of the locomotive on gradients is also a matter for consideration, the importance of which will be clear when it is stated that if an engine will haul, as it should, in addition to itself, ten times its own weight on the level, it will haul, speaking roughly, only four times its weight up 1 in 50, twice its weight up 1 in 25, and once its weight up 1 in 12. More work can be done if adhesion does not fail, but the above is an approximate working average. ”

“ By its adoption the use of existing rolling-stock is secured, transhipment is avoided, and the line can be subsequently and without difficulty transformed, if necessary, into a railway of standard construction—advantages for which much may be sacrificed. But as it would be almost invariably essential to build a light railway of sufficient strength to carry the 15 tons gross weight of a standard coal wagon, the permanent way would be of a somewhat costly character, and, in the case of severe gradients, considerable difficulty would arise in providing suitable locomotive power. ”

“ No train shall cross the road at a greater speed than five miles an hour, nor shall any train impede the traffic along the road further than is necessary for the crossing thereof, which shall in no case exceed three minutes.
(c) Every train crossing the road shall be in charge of a competent engine-driver and brakesman, and shall consist of not more than twenty-five vehicles, exclusive of the engine. ”

“ It would be well that our railway engineers should inform themselves more fully on the subject, as otherwise their valuable assistance, which would insure that narrow-gauge railways were constructed in a solid and reliable manner, will be thrust on one side by the requirements of the times, and the work will be wholly in the hands of the many manufacturers of narrow-gauge plant, whose designs, being chiefly of what is known as the portable class, are, for the most part, ill adapted for permanent locomotive traffic. ”

“ This attitude is probably due to ignorance of what can be done on the narrowest gauges, for, in spite of the fact that many hundreds of miles of lines of less than 2 ft. gauge are at work abroad, our professional advisers persist in regarding such railways as mere toys. Yet a line of 15 in. gauge has been at work in this country for twenty years, on which thousands of passengers have been carried without a single accident, as many as 120 in one train, over gradients as steep as 1 in 20, the goods traffic being worked in all weathers up a long gradient of 1 in 11 without difficulty. ”

“ The shops are lit by gas, and the 15 in. gauge line runs throughout. The construction, both in wood and iron, is done as far as possible to template, and every endeavour is made to turn out the very best work, which is perhaps the more easily attained in that there are no profits to be considered. At the same time it should be explained that the shops and machinery are, throughout, though good and sufficient for their purpose, in no way models of excellence. ”

“ Tire friction is practically nil, except on curves and in strong side winds. Journal friction I find, in the case of my small rolling stock, to be covered by an allowance of 10 lbs. per ton. Owing to the numerous curves another 10 lbs. per ton must be added to cover tire friction. A tractive power of 20 lbs. per ton proves quite sufficient to keep the train in motion on the level. It is not, however, enough to start the train on a curve, nor to overcome the inertia due to journal friction when, as on an incline, there is no slack between the wagons, and the whole train must be started at once. ”

“ It is probable that a traffic of 5,000 tons annually over a mile of line is the smallest amount that would repay the construction of a narrow gauge railway, for the estimate has been based upon the narrowest line which can profitably be employed. ”

“ There are probably many localities in which a diminutive railway like that at Eaton, ample in its capacity for estate requirements and extremely flexible in threading existing buildings, would well repay construction. The unobtrusiveness of so small a line and rolling stock, the relief to the roads, and the convenience of constant connection with the nearest railway, are points which are deserving of consideration where the conditions make such an installation possible. ”

“ By adopting the flat wagon as a standard, it is possible to adapt each one to any class of work, without the necessity of keeping a large variety for various purposes. A narrow gauge is said not to lend itself advantageously to the carrying of bulky material, but by loading a train of wagons without break from end to end, I clear hay off land, to which it happens that carts cannot have access, with great despatch. There is, therefore, no valid objection on this score. The cost of these wagons is from 80s. to 85s. per cwt. ”

“ The additional resistance due to friction of the moving parts of the mechanism cannot be calculated as a constant. If the engine is developing but a small portion of its power, the amount will be small; when loaded to its full capacity there will be a large increase of internal resistance, varying, however, in proportion to the accuracy with which it is put together, and the stiffness of the framing.
Such experiments as I have made show clearly that, when exerting approximately its full power, the total frictional resistance of the engine does not exceed 100 lbs. ”

“ Assuming its correctness, which appears beyond doubt, what is the explanation of increased proportionate adhesion with a decreased weight on the driven axles? The reduced diameter of wheel in the smaller engines might seem to offer a solution of the problem. Experience, however, goes to prove that, if there is any difference, a larger wheel has, with equal insistent weights, a better grip of the rail than a small one. ”

“ The engine-driver shall give three short whistles when he requires the brake-van brakes to be put down, and one short whistle when they are to be released. When he requires facing points to be set for the main line he shall give two, and for a branch or siding three medium whistles. A whistle continued for several minutes is a call for assistance, and workmen within hearing should at once proceed to the spot.
62. A red light is a signal to stop; a green light, to proceed cautiously; and a white light, to go a-head. In shunting, a green light, if waved up and down, is a signal to move a-head ”

“ Another somewhat curious point in connection with adhesion is the slip of the driving wheels, which is naturally in the direction of causing a greater number of revolutions of the wheels than would be due to the length of rail travelled over. Occasionally, however, I have, in experimenting, noticed that fewer revolutions are made than would suffice to travel the distance as measured on a centre line between the rails. ”

“ The cost of loading being the same for railway wagons as for carts is not considered. With a minimum traffic of 5,000 tons per annum over an average distance of 21⁄2 miles—equal to 12,500 ton-miles—the cost of transport is almost precisely 1s. per ton per mile; which is materially less than the cost of the cart haulage. The same rolling-stock and staff could readily deal with 40 tons per working day of eight hours—equal, at five days per week, to upwards of 10,000 tons a year. ”

“ In addition to a number of wagons, some of which are fitted with brakes, there are on my line seven bogie passenger cars and a bogie van; also a variety of miscellaneous stock, such as workmen’s car, screw and roller rail-benders, dynamometer car, and various small trolleys. The dynamometer car is constructed to indicate the tractive effort of the engine, the speed, and the distance travelled. The roller rail bender is worked by three men, two of whom work the winch which draws the rail through the rollers, while the third adjusts the pressure to produce the required curvature. ”

“ The permanent way should be made a thoroughly sound job, as it will then cost but little for repairs. Particulars of what is recommended will be found in Sections III. and IV. I am no advocate of portable railways, which may be well enough for hand trains, or even for horse traction, but a locomotive requires a solid and clean road if it is to work to advantage.
It is often possible to carry a narrow gauge railway by the roadside or, as at Eaton, over pasture lands without the necessity of fencing the line in. ”

“ If laid with pitch pine sleepers a reduction of about £100 per mile would be effected, the cost of renewal being correspondingly increased.
The engine would be capable of hauling a gross load, exclusive of its own weight, of 12 tons up a gradient of 1 in 50, which may be taken as a fair ruling gradient for a surface line. This would be equal to an average paying load of about 8 tons; so that, supposing the engine to make one trip per hour, about 60 tons would be moved per day; although, with a double set of wagons and men, 100 tons would easily be handled. ”

“ The wheels of such little locomotives, since speed is no object, should be kept as small as possible, and the stroke should be of the greatest length. The nearer the stroke can be extended to half the diameter of the wheel, the more successful will the engine prove on steep inclines. Good sand-boxes, front and back, of ample capacity are essential, but it is not advisable to fit any steam sanding apparatus, for, owing to the low position of the motion, a good deal of the sand will rebound into the joints and bearings, as I found by experiment. ”