So energetically did Meiggs pursue his self-appointed task that in six years he had carried the line 88½ miles into the Andes, and had gained an altitude of 12,215½ feet. All the men that he could possibly procure were pressed into service; at one time the railway gave employment to 8000 labourers. The amount of blasting necessary to prepare the road-bed for this single line of standard track was enormous, something like 500,000 pounds of explosives being used every month. The strain inseparable from such an enterprise told its tale at last upon the bold engineer, whose iron constitution could not withstand the anxieties and worries of the Verrugas fever, and the exposure to a rarefied atmosphere, without receiving an indelible mark. The first signs of a complete breakdown appeared as the railway was approaching Chicla, and when this point was gained in 1877 he succumbed. The removal of the guiding spirit brought the whole undertaking to a stop. Meiggs had completed two-thirds of the undertaking, and had broken the back of the difficulties. For fourteen years not another foot of line was graded. At last the Peruvian Corporation of London, which had taken over the railway, settled a contract for its completion with William Thorndike, who also hailed from Philadelphia. The new engineer carried the line a further 3,450 feet above the sea, following the surveys of Meiggs, and then became confronted with his greatest obstacle--the piercing of the summit crest. Thorndike had to hew his way through the bosom of a pinnacle for over 3,855 feet at an altitude at which such work never had been attempted before. The trying character of the situation was augmented by the rarity of the atmosphere, and the fact that he had to force his way through the region of the terrible mountain sickness, with a low prevailing temperature such as is encountered in the region of eternal snow and ice. Such conditions retarded the boring of the Galera tunnel, as it is called, more than the stern resistance of the rock. The workmen invariably fell victims to the sickness, though the undertaking was not accompanied with the heavy mortality that characterised the building of the Verrugas bridge far below. Mountain drilling, blasting, excavating, and the removal of the heavy spoil proved exacting and fatiguing, and a man could work only for a few hours at a stretch. By skilful organisation and careful husbanding of his forces, however, the engineer succeeded in forcing the metal track through the mountain at record speed.