One morning, before the dawn of what felt like a mid-May day, the expedition headed back along the trail mounted on mules, the best and surest-footed animals for mountain work. In order to prevent any unwelcome followers, the professor allowed it to be supposed that they were going back for a further exploration of the sacred city of Machu Pichu. When at last they were clear of the valley, with no one in sight, he called a halt, and carefully consulted his map at a point where the trail led in and out among slopes and hillocks of wind-driven sand.
"Here is where we turn off," he said finally.
Jud suddenly produced two large, supple ox-hides which he had carried rolled up back of his saddle.
"So long as we're goin' treasure-huntin'," he remarked "an' Scar Dawson is still above ground, I calculate to tangle our trail before we start."
Under his direction, the whole party rode on for a mile farther, and then doubled back and turned off at right angles from the trail, Jud spreading rawhides for each mule to step on. Their progress was slow, but at the end of half a mile they were out of sight of the original trail and had left no tracks behind except hollows in the sand, which the wind through the day would cover and level.
For the next three days Professor Ditson guided them by the map among a tangle of wild mountains and through cañons so deep that they were dark at midday. At night their camp-fire showed at times like a beacon on the top of unvisited peaks, and again like a lantern in the depths of a well, as they camped at the bottom of some gorge. Here and there they came upon traces of an old trail half-effaced by the centuries which had passed since it had been used in the far-away days when the Incas and their followers would journey once a year to the sacred lake with their annual offerings. Even although Professor Ditson had been to Eldorado before, yet he found it necessary continually to refer to the map, so concealed and winding was the way.
On the third day they reached a wide plateau which ranged just above the tropical jungles of the eastern lowlands. At first they crossed bare, burned slopes of rock, with here and there patches of scanty vegetation; but as they came to the lower levels they found themselves in a forest of vast cacti which seemed to stretch away for an immeasurable distance. Some of the larger specimens towered like immense candelabras sixty and seventy feet high, and there were clumps of prickly-pears as big as barrels and covered with long, dark-red fruit which tasted like pomegranates. Underfoot were trailing varieties which hugged the earth and through which the mules had to pick their way warily because of the fierce spines with which they were covered. Some of the club-cacti were covered with downy, round, red fruit fully two inches in diameter, luscious, sweet and tasting much like huge strawberries. Jud, who firmly believed that eating was one of the most important duties and pleasures of life, nearly foundered before they reached the pampas beyond the thorny forest. There they had another adventure in South American foods. As they were crossing a stretch of level plain, suddenly a grotesque long-legged bird started up from the tangled grass and, with long bare neck stretched out horizontally and outspread wings, charged the little troop, hissing like a goose as he came.