The instances above mentioned may be taken as mere specimens of the physical difficulties attending a work of this kind. There are often others arising from the unusual circumstances under which the workmen are placed, and others again from accidental causes alone. M. Favre experienced some of these, as, for example, when one year a fire destroyed the greater part of the village of Airolo; another year there was a strike on the part of the workmen. The high temperature in the workings was, especially towards the end, a source of great trouble. The cause of the heat is no doubt the same as that which is held to support the theory of the earth’s central heat. Numberless observations have established the fact that the temperature of the earth’s crust increases as we go deeper. The increase appears not to be uniform in different places—at least there is much discrepancy in the estimates that have been made. But as a sufficient approximation to a general statement, it may be taken as proved that for every seventy feet or so that you go below the surface of the ground, there is an increase of the temperature of the strata equal to 1° Fahrenheit. Now, the workmen in the two sections of the tunnel had, at last, to carry on their labour in a temperature of more than 100° Fahrenheit. This, perhaps, might have been one cause of some unprecedented kinds of malady that appeared amongst the tunnel labourers. M. Favre himself was not destined to witness the completion of his great undertaking, for, on July 19th, 1879, as he was returning from an inspection of the tunnel, he fell into the arms of his companions, struck down by a fatal attack of apoplexy. On February 29th, 1880, the last fuse required to blast down the rock separating the two tunnels was fired by one of the few workmen who had been engaged in the operations during the whole period from their commencement. It was found that the two tunnels met exactly and coincided in direction.
Fig. 187c.—The Bridges over the Maïenreuss near Wasen.
The construction of such a line of railway as the St. Gothard tries the skill of the engineer, and taxes all the resources of his art. The problems presented by the nature of the route, and the requirements of the iron road, have in this case been successfully solved by bold expedients—by new and ingenious devices. The reader will readily understand that the ordinary cart road may wander about, so to speak, of its own will; it is not confined to the limited gradient of the line; or obliged to make its turns and curves of at least a certain radius. Now, there are portions of the valley where the general slope is too steep for the railway to follow, and where it was necessary to form it in zig-zags, so that certain sections of the gorge or valley may be several times traversed by the line returning upon itself. Fig. [187d] is a view showing an incident of this kind, and one of the most interesting spots on the route. The dark line on the spectator’s right is the track of the railway; the white trace, which in the lower part of the view is seen on the other side of the Reuss, is the ordinary road. If this last be followed up the valley, it will be seen to cross first the Reuss, and then a tributary stream (the Maïenreuss) descending through a gorge on the right, after which it zig-zags up a hill to the village of Wasen (the church of which village is seen crowning the eminence in the centre of our view), and then it continues its course up the valley, passing through a small village, and disappearing over the shoulder of a hill on the right bank of the river. Let us now carefully follow the railway from where the train at the bottom of the picture is seen ascending the gradient. The line presently passes under a bridge, and then enters the tunnel, near to the entrance of which a small building will be noticed. The course of the tunnel is shown by the curve marked in dots, for this tunnel makes a round within the rock, and the railway emerges to day again at a point lower down in the course of the valley than at the entrance to the tunnel, but at a higher level. It is seen in the figure appearing from behind the rocks in the right-hand lower corner, passing under a short tunnel and continuing along the mountain side. The curved tunnel resembles in direction part of the turn of a corkscrew; it is one of a series of helicoidal tunnels of which there are several examples on the line. The entrance to this tunnel is 2,539 feet, the exit 2,654 feet, above the sea level. It is known as Pfaffensprung (Monk’s Leap) Tunnel. The line again enters a short tunnel, and immediately crosses the deep gorge of the Maïenreuss, to plunge again into another tunnel at the base of this hill on which Wasen stands. Higher up it crosses the Reuss and enters the helicoidal tunnel of Wattingen (dotted line). On emerging from this, the line re-crosses the Reuss, and may now be traced down the valley, but higher up on the mountain side, coming in the reverse direction, and after passing Wasen on the other side, re-crossing the Maïenreuss gorge by a second bridge. Then turning back again through another helicoidal tunnel (Leggistein) the line crosses the Maïenreuss for the third time, and continues its course up the valley. Fig. [187c] gives us a near view of Wasen, and a glimpse up the gorge of the Maïenreuss from its junction with the Reuss. The bridge with the large single arch is that which carries the ordinary road, and higher up we see the three iron bridges that carry the railway backwards and forwards in its doublings. We can well imagine the perplexity of anyone ascending the valley in the train for the first time, and ignorant of the peculiarities of this extraordinary railway. In crossing the first, or lowest bridge, over the Maïenreuss, he would catch a glimpse of the church of Wasen, perched on its hill, high above him, and on his right. After being carried through more tunnels, and over more bridges, he would some minutes afterwards be disposed to think that his eyes were deceiving him, for there, still on his right, he would see the same church, but now on about the same level as the train. Again, after more tunnels and bridges, the church would once more appear, transferred to the left of the line, and sunk very far down. These several apparitions of the same building in different positions, after the train has seemed to have been pursuing its onward course the while,—which course would not be judged by any impressions the traveller would usually receive to be other than rectilinear,—are indeed a regular bewilderment to the inexperienced traveller. He is then obliged finally to resign himself passively to be carried he knows not whither or how, for his sense of direction is completely at fault;—the train comes out of tunnels which seem turned the wrong way; the river, which he expected to find on the left hand, he sees on the right; and the Reuss appears to have reversed the direction of its flow.
Fig. 187d.—Windings of the Line near Wasen.
It is understood that the St. Gothard line has been a great commercial success, for the number of passengers entering and leaving Italy by that route has been enormous, and still shows a large annual increase. Indeed, the prosperity of the line has been so great that the project has been revived of carrying another railway over the Alps to connect Italy and Switzerland by way of the Simplon. If this scheme should be carried out, the mountains will be pierced by a tunnel of a length double that of the St. Gothard.
Fig. 188.