Changollo was headquarters for the construction-gangs working on the line. About half a dozen Englishmen and Scotchmen were in charge of the work, and they showed us every possible courtesy and attention during our brief stay there. I regret constantly that it is not possible to give detailed credit to all the people, South Americans and foreigners alike, who treated us with such unfailing courtesy throughout our years of travel in the southern continent, and to whose assistance we are so heavily indebted for the success that attended our efforts; but to do so would fill the pages of a volume several times the size of this one without leaving space for my narrative. All of the railroad men boarded with an Englishman named Cole and his wife. The Coles were a middle-aged couple who had spent the greater part of their lives together travelling around the world. Among other places, they had lived in India and in Africa. They had a score of parrots, cockatoos, and dogs that accompanied them in all their wanderings; caring for this miniature menagerie must have been a troublesome job while moving from place to place, but they took the place of children and were looked after just as tenderly. Cole claimed that he was the only man on earth who had been bitten by a black mamba--a species of giant cobra--and lived to tell the tale. He was following a path through the silent jungle one day at dusk when a black form lunged down upon him from some branches that overhung the trail; at the same time he felt a dull, throbbing pain in his left arm, and realized what had occurred. His first impulse was to flee in terror; however, better judgment prevailed and he opened and sucked the wound and applied a tourniquet above it. Then he hurried home and drank large quantities of ammonia and also applied some to his arm. He stated that he was very ill for several weeks but that persistent use of the ammonia overcame the effects of the poison and he gradually recovered.