Reise in die Aequinoctial-Gegenden des neuen Continents. Band 4.

An ambitious river expedition sets out at dawn to trace the hidden link between the mighty Orinoco and the Amazon via the Cassiquiare, a natural canal that splits the Rio Negro. The crew wrestles with thick, humid air and relentless mosquitoes as they navigate black waters, granite cataracts, and a maze of islands, while an indigenous guide promises clear skies and bright stars once they leave the river’s shadow. Their goal is precise: record the exact points where the Cassiquiare joins the Rio Negro and where the Orinoco forks, using astronomical observations that demand a cloudless horizon.

Along the journey the travelers marvel at striking geological formations—narrow quartz‑filled veins intersecting darker mineral channels, and ancient granite walls riddled with drusy crystals that hint at the region’s youthful age. The narrative blends meticulous scientific curiosity with vivid descriptions of jungle heat, mist‑laden mornings, and the relentless flow of massive South American rivers, inviting listeners to experience the awe and challenge of early exploration.