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total distance was 3,428 miles, as against 2,429 miles by the shortest possible route across the Alps by the Mont Cenis Railway. What Captain Tyler stated, in the interesting Report which was published last year as a parliamentary paper, with reference to the Brindisi route, was true, viz., that under ordinary circumstances, land conveyance by railway was at least twice as speedy as conveyance for the same distance by water ; and on the completion of the Mont Cenis Railway instead of there being as at present fifteen days between London and Alexan dria via Southampton, or eight days one hour which was the contract time for the mails via Marseilles, the time of transit would only be six days seven hours, so that the journey would, under an arrangement with the Italian government, be shortened by forty-two hours. This was an important consideration with regard to the postal service. The weight of the outward Eastern mails via Southampton was in 1865 upwards of 700 tons, and by measurement 1500 tons; and in 1866 they were still heavier. It was, therefore, of great importance, to England in particular, that a system of railway across the Alps which would give the utmost possible facilities should be carried out. He had no doubt in his own mind, speaking as a person connected with railways for many years, that in the course of the next few months the 1,504 miles, which constituted the distance between London and Brin disi by the Mont Cenis summit line, would be accomplished at an aver age rate of 20 miles per hour. He had prepared the following table, giving the different carriage roadway passes which now existed across the Alps; and he had included one or two that were not actually carriage roadway passes— Alpine Roadway Passes. Name. Width. Summit above Sea Level. Distance via London to Brindisi. Break in Railway. Semmering . . . Feet. Feet. 2893 Miles. Miles. Brenner .... 25 4650 1769 73 Stelvio 16 to 18 9272 Splugen .... 15 to 18 6940 Bernadino . . . 15 7115 Lukmanier . . . 6500 St. Gothard . . . 18 6808 1483 146 Simplon .... 15 to 30 6636 1471 114 New Route . . 1435 114 Great St. Bernard . 8200 Little St. Bernard . 6780 Mont Cenis . . . 18 to 30 6658 1504 48 Ditto, Tunnel . . Mont Genevre . . 4118 1498 42 5850 Col di Tenda . . 5890 1833 118 Corniche Road . . 30 2200 1796 127 as, for instance, the Luckmanier Pass, as, although there was no actual roadway across the mountains by that pass, yet it possessed great facilities for the construction of a railway; and no doubt a line on Mr. Fell’s system could be made along that pass. England was more particularly interested in the passes on the western side of the Alps, because it was by means of one or more of them that the nearest com munication by railway with Brindisi was to be obtained. It would bo seen that, by the Mont Cenis summit line, Brindisi was 1,504 English miles from London, as calculated by Captain Tyler in his Report. When the tunnel, which although it had already been nine years in construction was, on the 15th October last, only half perforated, was completed, a saving of only 6 miles would be obtained at an enormous cost. There was no doubt the cost of the Mont Cenis tunnel would exceed the estimate of Captain Tyler. Sir Cusack Roney believed it would be two-thirds more, and all that cost would be incurred for a saving of 6 miles. In addition to that it would be seen that, though the summit line -was at an elevation of 6,658 feet, there was a gain of only 2,500 feet by the tunnel line, in consequence of there being a con tinuous rising gradient in the tunnel from each entrance to exactly the centre. The nearest route between London and Brindisi would be by the Simplon line ; the exact distance by that route being 1,471 miles. With a short line, which would cut off an angle in the railway com munication between Paris and Lausanne, there would be a saving of 36 miles, thus eventually reducing the distance between London and Brindisi to 1,435 miles. The only railway now actually existing across the Alps was the Semmering. Its summit was at an elevation of 2,893 feet. An interesting Paper on that railway was presented to the Institution some years ago, and he need not refer to it further. A line of railway through the Brenner pass was in course of construction, and would be opened about August next. Mr. Conybeare said, as Engineer to several lines traversing the mountain districts of North and South Wales he had had a good deal to do, during the la^t ten years, with the laying out and working of lines of exceptionally steep gradients. On these railways, the longest continuous length of steep gradient occurred on the Brecon and Mer thyr, in descending from its summit level (situated on the mountain range known as the Brecon Beacons) to the valley of the Usk. The descent was 900 feet in 6 62 miles, giving an average gradient of 1 in 38'8 and the curves varied from 25 to 40 chains radius. This portion of the line was laid out in 1856, the plans were deposited in 1858, and the line was opened for traffic on April 19, 1863, but it had been worked over with heavy engines for twelve months previously. The rails weighed 70 lbs. to the yard. The total length of the Brecon and Merthyr at present completed was 89 miles, and a considerable portion of it was on these exceptionally steep gradients. The ascent from Merthyr to the level of Dowlais was 5} miles at 1 in 49, and in the 20 miles between Dowlais and Brecon there were 6£ miles steeper than 1 in 39, and 1 mile 70 chains of 1 in 40, making 8»- miles out of the 20 miles, of 1 in 40 or steeper. As Captain Tyler had oberved, the opinion of Engineers regarding the economical limit of steepness of gradients had undergone a great revolution of late years. In closing the last discussion that took place on this subject, Mr. Bidder expressed the opinion that the working ex penses alone of a gradient of 1 in 40 with an up-hill load would be from 3d. to 4d. per ton per mile, and even with a down-hill load, would absorb the whole receipts, leaving nothing whatever for interest on the cost of the rolling stock. This opinion was quoted at public meetings held in 1859, to prove that the Brecon and Merthyr, and the Merthyr and Abegavenny (another line in the district with similar gradients, to which he was the joint Engineer), could not be remuneratively worked. The portion of the line on which the steepest gradients were situated had been used for traffic since the spring of 1862. The particulars of the cost of working, furnished by Mr. Henshaw, the traffic-manager and locomotive superintendent, showed an unusually favourable result, both as regarded adhesion and economy of working. Tank engines were used, having six wheels coupled, of 4 feet 6 inches diameter, with a wheel base of 12 feet; the cylinders were 17 inches in diameter, with a length of stroke of 24 inches. The saddle tank contained 1,100 gallons of water. The weight of the engine in working order was 38 tons. The engines and break vans were furnished with large sand boxes, the supply of which was carefully attended to. The weight of the break van was 8 tons. All the passenger carriages were supplied with Fay’s continuous break. The working pressure, 100 lbs. on the square inch, was maintained throughout the ascent. These engines took a regular load of ten loaded wagons and two break vans, weighing altogether 136 tons gross, at the regulated speed of 8 miles an hour, up this gradient of 6 miles 50 chains oi 1 in 38. The engine “ Cymbeline” was built by Messrs. Sharp, Stewart, and Co., specially for this line, after a careful consideration of the facts of the case, and of the experience gained in previous working. During the month of December, 1866, this engine ran between Brecon and Dowlais, a distance of 20 miles, out of which there were more than 81 miles with gradients varying from 1 in 38 to 1 in 40, with the fol lowing results :— Working of the Engine “ Cymbeline,” December, 1866. Miles run 1,897 Coal . 703 cwt. 41'5 lbs. per mile. Oil 45 pints •023 pt. „ Tallow . . 44 lbs. •023 lb. „ The cost per 100 miles, including wages, was £1 8s. 3Jd., or about 3fd. per train mile, with a net load of 85 tons. He attributed the high rate of effective adhesion of these engines, and their economy of working, to two causes—first, that they were specially and carefully designed for the particular work they had to do ; and, secondly, that there was only 1 curve sharper than 25 chains radius on the ascent. According to his experience, Captain Tyler adopted too low a figure in taking the effective adhesion that might be relied on in ordinary working at only th of the insistent weight. On the other hand, he was altogether incredulous as regarded the alleged instances of a maximum of T77, or a little over |th being exceeded, even under the most favourable circumstances. It was well known from the ex periments of Morin and Rennie, that the coefficient of friction of wrought iron on wrought iron, where no unguents were interposed was •177, or, in other words, that it would require a horizontal force of a little over |th of the insistent weight to make a mass of wrought iron slide on a plane surface of the same material, and it appeared to be a necessary corollary that, when the resistance of the load exceeded *177 of the weight on the driving wheels, the latter must slip on the rails. He was aware of the American instances adduced of the alleged utili sation in draught of as much as [th and even §ths of the insistent weight; but, on looking carefully into these instances, the data would not be found to warrant such a conclusion. It would ue seen that in all the instances (where really precise data had been given), in which so exceptional a result was claimed, the motor had been a bogie engine; and Mr. Zerah Colburn, in speaking of instances where the effective adhesion was stated to have been as high as Jths, remarked that this was the nominal weight on the driving-wheel, and that it must be