At the height of the 19th century’s Industrial Revolution, trains became essential for manufacturing and trade. A major obstacle to connecting Southern Europe with Northern Europe was the Alps of Switzerland. The businessmen and industrialists of the age saw the advantage of trade between Italy and Germany and so plans were laid to build the St. Gotthard Tunnel, the second passageway through the Alpine mountains to be built at that time. After fierce negotiations and attacks from skeptics who believed it could never be done, the project was put into the hand of Louis Favre, an engineer from Genoa.
    The St. Gotthard Tunnel committee allotted Favre eight years to complete the project which began in 1872. Favre decided to use what was called the Belgian method of tunneling. This involved the building of a pilot tunnel along the crown, digging trenches down along the sides to provide support for the walls, drilling holes into the floor of the pilot tunnel, filling them with dynamite, blasting out the rock and soil, then removing the debris in carts and small trains. Then a portal is installed to hold the next section in place while the workers continue on building the next section of pilot tunnel. The walls are later lined with bricks and scaffolding is built to support the ceiling.
    Since St. Gotthard was only the second mountain tunnel to ever be constructed, choosing a quality rock drill proved to be a challenge, mainly because there was no history of engineering such drills and many different models had to be tried before the best one was chosen. Favre settled on the Ferroux machine and set to work. The Ferroux was a hydraulic-air compressor machine in which spinning turbine forced water through pipes to build up enough air pressure to force the drill bit to rotate at about 3 or four revolutions per minute. The process was slow and workers were lucky if they could complete 5 feet of tunnel extension per day. Laborers worked eight hour shifts all day and all night and the tunnel was dug from both the north and south ends at the same time, then the two ends would eventually connect in the middle.
     As they dug the tunnel further, a number of complications arose. The first was the incredible heat. Temperatures under the Alps sometimes reached above 40 degrees celsius which was a condition not suitable for heavy manual labor. Ventilation presented another problem; air ducts were built along the way as pilot tunnels were continuously made but the farther in the workers drilled, the less effective the ventilation system was. Noxious underground gases and exhalations from men and animals quickly made the tunnel a difficult place for breathing. The hydraulic pressure used to circulate the air also proved to be too weak to effectively ventilate the deeper reaches. Engineers later had to re-design the air-pump mechanisms to ensure they did not suffocate all the workers. Water drainage was another major problem. Water seeping downward from the upper layers of rock and soil created a constant rain. The builders also burst underground water reservoirs which gushed water into the tunnel. It was common for laborers to be working ankle deep, knee deep, or even waist deep in floodwaters most of the time during their drilling. Then partway through to completion, Favre ran out of money. After scrambling to raise more funds he eventually died of a heart attack at the age of 55. During the construction of St Gotthard Tunnel, about 25 men died each month. The number of injuries was uncountable and so was the number of animals who died from exhaustion.
    Towards the completion of the tunnel, the workers built a passageway through a section of decayed feldspar and gypsum. This caused heavy water leakage and huge amounts of moisture began to condense on the mortared lining of the walls and ceiling. The result was a degeneration of the bricks into a heavy clay-like substance that put too much weight on the wooden support beams holding them up. A section of the tunnel collapsed. At first this seemed like the end of the project but the engineers succeeded in building a stronger support arch for the ceiling and making a concave inverted floor beneath the tracks and support beams to absorb some of the pressure coming from above.
    Finally, several months after it was scheduled to finish, the two ends of the tunnel met in the middle. Two railroad tracks were built and the St. Gotthard Tunnel was opened, successfully connecting Italy and Germany via Switzerland.
Sandstrom, Gosta. Tunnels. Holt Rhinehart and Winston, New York, 1963.