Diario de la navegacion empredida en 1781 / Desde el Rio Negro, para reconocer la Bahia de Todos los Santos, las Islas del Buen Suceso, y el desague del Rio Colorado

A pilot’s navigational diary records an 1781 expedition from the Río Negro to survey a coastal bay, nearby islands, and the Colorado River mouth. It combines a preliminary account of colonial preparations and command disputes with day-by-day log entries documenting navigation, anchoring, channel sounding, and placement of beacons. Observations detail tides, shoals, river width and depth, saline lagoons, vegetation, and the routes and settlements of local indigenous groups. Practical notes on ship condition, provisioning and repeated reconnaissances produce a pragmatic hydrographic and topographic report intended to guide future navigation and settlement.