Five and a quarter miles in length, which occupied five years to bore through the range
RAILWAY BUILDING IN THE TYROL
On the northern side of the tunnel similar arrangements were laid down. In this instance, however, the electricity, obtained by harnessing two small waterfalls, had to operate wonderful electric drills which were used at this end for boring into the rock—on the southern side hydraulic and pneumatic drills were employed. The working face in the tunnel was illuminated brilliantly by electric light, so that the drillers laboured under conditions vastly dissimilar to those which prevailed when the first Alpine tunnel was driven. As the top of the tunnel was cut out the roof was shored up with heavy timbering, and hard on the tracks of the excavators came the stonemasons, cutting, trimming, and setting the masonry lining into position. The work was so planned that the actual progress per day should be thirteen lineal feet, and although at times the calculations were somewhat upset by something unforeseen being encountered, yet, taken on the whole, the average was well maintained. Commenced in June 1902, the mountain chain was pierced and ready for the double line of rails by November 1905, so that the work had been carried out very smartly indeed.
ONE OF THE HUGE LOOPS ON THE TAUERN RAILWAY
Showing heavy character of earth cutting and masonry work.
Emerging from the tunnel, the line once more becomes a single track, and issues into the Wurzner Save valley, the descent continuing until Assling, the terminus of the Karawanken railway, is reached, this point being 151 feet below the southern mouth of the tunnel. Here a connection is formed with the next link in the chain, this being the “Wochenier” section, which runs to the shores of the Adriatic at Trieste.
But before the latter terminal is gained another mountain mass has to be penetrated—the Julian Alps. It is a meandering line in very truth, for the configuration of the country prevented more than short pieces of straight track being sandwiched here and there between sweeping curves, elaborate winds, stiff ascents and descents—in fact, the longest piece of straight line is only of 6,600 feet in the first 55 miles. In running from Assling to the seaboard 28 tunnels are threaded, exclusive of the Wochenier, which is 4 miles long, 15 bridges and 30 viaducts are crossed, while the cuttings and embankments are innumerable. The railway traverses some of the most romantic and wildest scenery in the whole Alpine chain, especially as it approaches the southernmost clump of these mountains.
On this section the engineers accomplished an unparalleled engineering feat. The narrow Isonzo gorge had to be crossed, and it was effected by throwing a single span from one bank to the other, a matter of 733 feet. This is the longest single-arch masonry bridge in the world, and the rail-level is 120 feet above the level of the water. As the coast is approached the windings of the line become more tortuous, while the bridging, owing to the numerous rivers, is terrific. When at last Opcina tunnel is penetrated, the Adriatic is seen spread out in a vast panorama 1000 feet below.
To descend the mountain slopes with an easy grade for a distance of ten miles was a stiff problem. In order to do so the engineers had to carry the track in the form of elaborate saw-like loops. Heavy gradients could not be avoided, and this part of the line is one of the steepest and most trying to the locomotives.