 This trip, which lasted four months and covered of wild and largely uninhabited country, had an aim of establishing the existence of the Casiquiare canal (a communication between the water systems of the rivers Orinoco and Amazon).Although, unbeknownst to Humboldt, this existence had been established decades before, his expedition had the important results of determining the exact position of the bifurcation, and documenting the life of several native tribes such as the Maipures and their extinct rivals the Atures (several words of the latter tribe were transferred to Humboldt by one parrot).Around 19 March 1800, Humboldt and Bonpland discovered dangerous electric eels, whose shock could kill a man.