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were in parts of the distance accumulations of hardened snow, so great that the surface on which the sledges ran was many feet above the surface of the road. The changes in the condition of the snow were very rapid, and a few hours would sometimes suffice to render the pass impracticable for days, and travellers were occasionally stopped half way on the Pass, and had no means of proceeding or returning. He supposed that few railways were exposed to the effects of snow to so serious an extent, and under such peculiar circumstances. There were railways, both in Europe and in America, subject to heavy falls and long continuance of snow, and then the road was cleared by the use of the snow-plough—often a heavy and tedious operation. He was aware that, to a certain extent on the Mont Cenis line, covered ways were proposed, which he supposed were more particularly intended as a protection from avalanches; but he hoped that Mr. Brunlees would in form the meeting, what he anticipated would be the effect of heavy snow-drifts, and large accumulations of the snow upon Mont Cenis, in the working of the railway under consideration, how he proposed to meet the difficulties of the case, and what special provisions he pro posed to adopt to keep the snow clear from the middle rail, so as to give the necessary adhesion to the horizontal wheels. Mr. Brunlees wished in the first place to remove any misapprehen sion that might have arisen. To Mr. Fell, as inventor or perfector of the central rail system, would belong the merit of any success which might be achieved by the Mont Cenis Railway. His own share in the undertaking had been simply to see that the system was properly carried out, and the line efficiently made, and that there was due pro vision against the accumulation of snow, either by drifting or the falling of avalanches. It was true that there was on certain parts of the route great liability to avalanches ; but they had been guarded against as far as possible by the construction of covered ways of masonry. For other portions of the line, comprising the snowy range, where drifts of great depth occurred, timber and iron covered ways were provided ; and on the intermediate section, between these covered ways and the avalanche galleries, such observations were now being made as would, it was believed, enable him in the course of next summer to provide screens that would in various places free the line from drifts. From the point where the timber-covered ways com menced on one slope of the mountain, to the termination of the covered ways on the other side, in all about 10 miles, the snow lay for about five months in the year. With respect to the mode of working the level crossings with the middle rail, the first plan he thought of was that of canting the middle rail over on its side, and bringing it down to the level of the two ordi nary rails. To that there were, however, many objections. Air. Barnes had suggested a method of supporting the central rail at the level crossings on upright bars, hinged at their base and at their con nection with the under side of the rail, and which could by a motion similar to that of a parallel ruler, be letdown to the same level as the ordinary rails, which were crossed in the usual manner. He believed that this was the best way of dealing with the crossings. The effect of severe frost was provided against by everything being left free and open so that the ice could not accumulate. The snow plough he proposed to place on the Mont Cenis Railway was of a form suggested by Mr. Alexander, who had had great experience in dealing with snow in Canada. Various descriptions of ploughs had been adopted by different railway companies, but he believed this would prove the best. The under-part of the plough was fixed, and would clear the snow from the level of the ordinary rails to about the level of the central rail. Then as it was not allowed to turn the snow on to the turnpike road, which ran parallel to the railway, piovision had to be made for shifting the upper part of the plough from the left to the right, or vice versa, so as always to throw the snow off on to the side of the railway next the precipice. This was effected by means of a rack-movement at the back of the plough, which enabled the machine to be directed to the right or the left as occasion required. He thought that by this or a similar plan any ordinary snow-fall might be got rid of. The annexed Table which he had prepared, of the available power derived from the various engines hitherto found most effective in working inclines, showed the superiority of the central rail system. Air. Pole would offer a few remarks on one or two points that had incidentally been mentioned in the Paper or in the discussion. Cap tain Tyler’s Paper might equally well have been entitled “ On the Passage of the Alps by Railways;” and this of itself would form an interesting subject for the Institution. He was surprised to find it so little known in England, that there was already a railway nearly finished across the main chain of the Alps, and, what would probably be thought still more surprising, without any long tunnel or any such very steep gradients as had been referred to in the Paper. This was across the Tyrolese Pass of the Brenner, between Afunich and Verona. He had occasion to cross this Pass in 1865, and was amazed to find this railway in progress, of which he had never before heard. Being thus unprepared, he had no means of getting detailed information about it, but he followed its line along the whole length, and would state what he knew. The railway had already been finished up to Innsbruck on the north side, and to Botzcn on the south side, the distance between these places in a straight line being about 80 miles by the carriage road, and involving the pass of the Brenner at nearly 5,000 feet above the sea. At Innsbruck the line lef. the main valley of the Inn, and turned abruptly southward, ascending the small tributary of the Sill, till it arrived at the summit of the Pass, which it crossed alongside the car riage road, without any tunnel through the ridge. From thence it descended the stream of the Eisach, a tributary of the Adige, down to Botzen, where it entered the main valley, and joined the railway already made by Trent to Verona, and communicating there with the railway system of Northern Italy. The rise from Innsbruck to the summit was about 2,850 feet, and the road was 28 miles long ; but as the railway made several detours round lateral valleys to gain length, the average gradient would probably be only about 1 in 70 or 1 in 80. The fall from the summit to Botzen was about 3,500 feet, but there was nearly twice the length to do it in. Of course there were some places where the nature of the ground required steeper gradients ; but he was informed the steepest did not exceed about 1 in 40, which was quite practicable for locomotives of ordinary construction. There were several short tunnels through spurs, and a good deal ofheavy rock work, but he did not observe any extraordinary difficulty in the line. It was tar advanced when he passed it; and he was informed the works had been vigorously continued since, and that the line was to be opened