The way lay across a low, forested ridge, and then adhered closely to the bamboo-covered banks of a small stream called locally Rio Cabeceros or Rio Vueltas, but which is really the headwaters of the Sipi River. At one time we waded in the knee-deep water a distance of over three miles, as it was easier than to force a way through the matted plant life on either side. I soon discovered that the porters did not possess the endurance of those we had previously employed on other expeditions, and I believe this was due to the fact that the use of coca leaves is unknown in this part of Colombia. Whenever our _peons_ had an abundance of coca to chew they seemed tireless in the performance of their work; those not given to the habit required large and frequent meals, ate _panela_ all day long as they marched, and were capable of covering a short distance only in the course of a day’s walk. We were compelled to halt early and chose the top of a knoll for a camping site. A steady downpour of rain had fallen the entire afternoon, which continued throughout the night, and this, coupled with the severe cold (the elevation being seven thousand two hundred feet) and the desirability of preparing hot food, caused us to long for the comforts of a huge camp-fire. Dry wood was out of the question, but the men cut down a tree, the green wood of which burned readily, and had soon started a fire adequate for working purposes. Their ponchos, which had become saturated with water, were of no service in keeping them warm, so they sat up the entire night, singing, telling stories, and drinking hot coffee in their endeavors to remain cheerful and keep warm. On the following day the vegetation was far more dense, and advantage was taken of numerous narrow fissures in the mountainside roofed over with logs and moss; through these tunnels we crawled on hands and knees, but that was easier than forcing a way through the tangled mass of plants growing above. When camp was made that night the base of a tree was selected for a fireplace. At first glance it seemed that the diameter of the vine-covered trunk must be at least ten feet, but this was a delusion. After the men had vigorously plied their machetes on the creepers, moss, and ferns, a stem not over two feet across was revealed; they cleared away the lower tangle, leaving a protecting umbrella-like canopy overhead that shielded the entire party from the rain while they cooked their food. We crossed three ridges in all, the elevation of each being slightly in excess of seven thousand feet, with depressions of from two thousand feet to three thousand feet between them. All are heavily forested, the growth above four thousand feet being subtropical in character, while that lower down is typical of the tropics and comparatively open.