Correspondence on New Zealand and Ceylon
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120 DISCUSSION ON NEWZEALAND RAILWAYS. minutes of Mr. Longridge. was satisfied the results he had given were substantially correct, and would be borne out by experience in such a country as was referred to. Mr. Barlow. Mr. W. H. BARLOW,President, said it appearedto him impos- sible to inculcate any general laws for the laying out of railways suchas those described inthe Papers. There weredominant Circumstances which must control them. It was so even in England. On a part of the railway with which he was most inti- mately concerned, the Midland, there was an incline of 1 in 37 which had been made for many years and had a large traffic over it, and on other parts there were gradientsof 1 in 120. The com- pany had been spending large sums of money in improving the gradients on 1 in 120, while they had not felt it necessary to improve the gradient of 1 in 37. That showed that the circum- stances of the traffic might regulate such matters as well as the circumstances attending theconstruction. Correspondence. Mr. Abt. Mr. R. ABT wouldcompare theconditions of theline from Wellington to Woodville with those of two similar lines, one of whichwas worked by an ordinary tank locomotive, while the other was a rackrailway. The first of these, theUetliberg railway, was fully described in the foreign abstracts.' The secondwas the Rorschach-Heiden railway. Rorschach was a main station of the 'United Swiss railways, on the shores of the Lake of Constance, 1,320 feet above the sea. Heiden, 2,600 feet above the sea,was a well-knownpleasure resort. The railway between the two hadto facilitate the journeyof visitors to Heiden, and at the same t.ime to serve a good many quarries situate near the middle of its length, at the Wienachten station. It had been opensince 1875. Thetrains were made up on the quay at Rorschach, and first ran for abont 1 mile over the track of the United Swiss railways. This part was nearly level, and had only a few curves, of large radius. The incline was 3 miles 188 yards long. The steepest gradient. was 1 in 11 ; the curves were gene- rally of 600 feet radius. The gauge was 4 feet S& inches, as the goods wagons of the other Swiss and French railways hadto pass over the line as faras the quarries at Wienachten. The rails were 3$ inches high, and weighed 40 1bR. per yard. The wooden cross- sleeperswere spaced 24 feet apart. On thecentre line of the railway was a rack, exactly like that on the Rigi. Vide Minutes of Proceedings Inst. C.E., vol. xl., p. 275, and vol. xlix., p. 307. Downloaded by [ University of Sussex] on [18/09/16]. Copyright © ICE Publishing, all rights reserved. Proceedings.] CORRESPONDENCECEYLONON RAILWAYS. 121 The railway wasworked by three rack-wheel locomotives, built Mr. Abt. at the late engine works at Aarau. At first the level part of the line, from the quay at Rorschach to the foot of the incline, was worked by adhesion-locomotives of a special type. But as the line had a very small traffic, and this arrangement greatly increased the expense, in 1878 the rack-locomotives were modified, so that, by the help of the adhesion of one pair of wheels, they could run on the ordinary rails, without a rack, to the quay. The principal dimensions of these locomotives were as under :- Diameter of cylinder, 11 -8 inches ; stroke, 20 inches ; boiler pressure, 150 lbs. ; grate surface, 10%square feet ; heating surface of fire-box, 62 square feet ; ditto of tubes, 475 square feet; total, 538 square feet : weight empty, 12%tons ; with fuel and water, 16i tons; wheel base, 10 feet; diameter of travelling wheels, 32+ inches; of the rack-wheel, 41 inches. There were sevencarriages for summer traffic, weighing 214 lbs. for each seat ; and twofor winter traffic, heated by steam, weighing 482 lbs. per seat; giving 414 places in all. All the carriages had brakes for the rack-wheel. The railway possessed only eight goods wagons of its own, weighing each about4 tons, and carrying about 79 tons. The cost of the railway, including materials, was;E90,000, or %25,664per mile; which sum, considering that the difficulties of construction were moderate,seemed extraordinarily high. The normal capacity of the engines, very seldom utilised, was to draw a train of 39 tons (exclusive of the engine) at a mean speed of 5 to 6 miles an hour in ascending, and 6 to 7: miles in descending. The expenditure of coal was 53 lbs. per train-mile. The whole working expense per train-mile was 4s. 2d., of which 28. was for running expenses. A comparison of the performances on these two lines with that on the Featherston incline gave the following :- Load Drawn on Railway. llnclineof l in Is.)Averege Weight LoT&~~~~ motive Weight. 1-- exclusiveEngine. of I of Locomotive. Tons. l Tons. Tons. Wellington and Woodville . 1 64 36'0 1.8 Uetliberg . 26 23.5 1.1 Rorschach and Heiden . 1 58 15.5 3.7 The speed on the Uetliberg railway (9: miles per hour) was about twice as great as on the other two lines. The work done, Downloaded by [ University of Sussex] on [18/09/16]. Copyright © ICE Publishing, all rights reserved. 122 CORRESPONDENCE ON NEW ZEALAND RAILWAYS. minutesof Mr. Sbt. considering that it was a simple adhesion system, was large; on the other hand, the safety was certainly less than with the Fellor rack systems. The first cost and the working cost must, however, be less with the simple system. The working cost for such small local lines was not really comparable with that on mainlines, because it depended on so manydifferent circumstances. There was a decided difference between the results of the two special systems, the Fell and the rack railway. On an incline of 1 in 15, the rack locomotive, weighing 16.5 tons, drew almost as much as the Fell locomotive, weighing 36 tons. Mr. Abt would undertake, from actual experiment, to build a locomotive of about 16 tons, which on an incline of 1 in 15 should draw, besides itself, a load of 70 to 1’75 tons, or 4$ times its own weight, at a speed of 5 miles per hour. The permanentway for rack railways consisted, besides the rack, of exactly the same pieces as for an ordinary railway. The rack and its fastenings cost at present 218. per lineal yard,or, with laying, 228. 6d. to 22s. 9d. Probably it would cost slightly more than the central rails and theirfastenings of the Fell system. The safety, however, with the rack systom was higher than with the other, especially in bad weather and with much snow. The rack engines of the LL mixed system,” which were built byMr. Abt at the Aarau works, possessed equally with the Fell engines the power of moving, both on the rack by the rack-wheels, and on ordinary lines by adhesion ; but the speed in the latter case was only a littlehigher than on the rack.Since this problem had been satisfactorily solved by rack engines on the mixed system, and several engines had proved thoroughly satisfactory in working, he believed thatin most cases, wherethe introduction of a steep incline was needed, its working by rack railway would be muchmore advantageous thanby the Fell system.The rack itself, after ten years’ service, showed not the slightest wear; the expense of lubrication (2 -468. per mile of track per annum) was not worthmentioning. Again, the expense of lubricatingthe specialrack-gear was small, sayone-third the average cost for ordinary working parts. The heaviest expense was that of main- tainingthe gear itself. Thelargo rack-wheel cost about 3240, and would run 30,000 miles before it needed changing. The inter- mediate wheels cost together 3280, and would run 50,000 miles. M~.Alford. Mr. R. F. ALFORDhad been engaged in designing the Fell engines, under Mr. Widmark, at theAvonside Engine Company, and, through the courtesy of the consulting engineers for New Zealand and the manufacturers- he was ableto submit the following information :- Downloaded by [ University of Sussex] on [18/09/16]. Copyright © ICE Publishing, all rights reserved. Proceedings.] CORRESPONDENCE ON CEYLON RAILWAYS. 123 In the first place, a slight error had crept into the Paper as to the Mr. Alford. stroke of the inside or Fell cylinders. They were not 12 inches in diameter ancl 15 inches stroke, but 12 inches in diameter and 14 inches stroke. This altered the tractive force from 96 lbs. to 89 6 lbs. per lb. of effective steam in the cylinders. The weight of the engine hadbeen also stated slightly high; the weight empty being 27%tons at Bristol ; there had been a slight alteration in the cab, but this could not add more than 2 or 3 cwt., which gave a total weight of 302 tons and 343 tons iu running order, with the tanks and coal-boxes empty and full respectively, and a calculated weight of 25 tons 8 cwt., 26 tons 6 cwt., and 27 tons 3 cwt., on tho coupled wheels, with the tanks empty, half full, and full, respec- tively. The calculated adhesive working pressure due to the four Fell wheels was 26 tons 6 cwt., or 13 tons 3 cwt. on each side of the rail,giving 6 tons 114 cwt. perwheel; but more or less pressure could be put on if thought desirable, and at a trial of one of the engines at Bristol the Fell wheels drew the engine back- wards with full steam on both engines ; the tanks and coal-boxes were filled, so asto give the highest possible adhesion tothe coupled wheels of the ordinary engine.