After going about two thousand three hundred miles up this serpentine river, we discovered the entrance to the lake. Many had been the conjectures and counsels of would-be advisers when we started. Some said that there was no entrance to the lake from the river; others, that there was not sufficient depth of water for the steamer to pass through. On our port bow rose frowning rocks of forbidding aspect. Drawing nearer, we noticed, with mingled feelings of curiosity and wonder, that the face of these rocks was rudely carved by unmistakably Indian art. There were portrayed a rising sun, tigers' feet, birds' feet, etc. Why were they thus carved? Are those rocks the everlasting recorders of some old history--some deed of Indian daring in days of old? What these hieroglyphics signify we may never know; the workman is gone, and his stone hammer is buried with him. To twentieth century civilization his carving tells nothing. No Indians inhabit the shores of the lake now, perhaps because of this "writing on the wall."

With the leadsman in his place we slowly and cautiously entered the unexplored lake, and thus for the first time in the world's history its waters were ploughed by a steamer's keel.

Soon after our arrival the different guards were told off for the silent watches. Night shut in upon the lake, and all nature slept. The only lights on shore were those of the fire-flies as they danced through the myrtle boughs. The stars in the heavens twinkled above us. Now and again an alligator thrust his huge, ugly nose out of the water and yawned, thus disturbing for the moment its placid surface, which the pale moon illuminated with an ethereal light; otherwise stillness reigned, or, rather, a calm mysterious peace which was deep and profound. Somehow, the feeling crept upon us that we had become detached from the world, though yet we lived. Afterwards, when the tigers [Footnote: Jaguars are invariably called tigers in South America.] on shore had scented our presence, sleep was often broken by angry roars coming from the beach, near which we lay at anchor; but before dawn our noisy visitors always departed, leaving only their footprints. Early next morning, while the green moon was still shining (the color of this heavenly orb perplexed us, it was a pure bottle green), each one arose to his work. This was no pleasure excursion, and duties, many and arduous, lay before the explorers. The hunter sallied forth with his gun, and returned laden with pheasant and mountain hen, and over his shoulder a fine duck, which, unfortunately, however, had already begun to smell--the heat was so intense. In his wanderings he had come upon a huge tapir, half eaten by a tiger, and saw footprints of that lord of the forest in all directions.