He started from the Gambia, and after many adventures, in which he was captured by the Moors, arrived at the banks of the Niger, which he traced along its middle course, but failed to reach as far as Timbuctoo.
He made a second attempt in 1805, hoping by sailing down the Niger to prove its identity with the river known at its mouth as the Congo; but he was forced to return, and died at Boussa, without having determined the remaining course of the Niger.
Attention was thus drawn to the existence of the mysterious city of Timbuctoo, of which Mungo Park had brought back curious rumours on his return from his first journey.

This was visited in 1811 by a British seaman named Adams, who had been wrecked on the Moorish coast, and taken as a slave by the Moors across to Timbuctoo.

He was ultimately ransomed by the British consul at Mogador, and his account revived interest in West African exploration.

Attempts were made to penetrate the secret of the Niger, both from Senegambia and from the Congo, but both were failures, and a fresh method was adopted, possibly owing to Adams' experience in the attempt to reach the Niger by the caravan routes across the Sahara.

In 1822 Major Denham and Lieutenant Clapperton left Murzouk, the capital of Fezzan, and made their way to Lake Chad and thence to Bornu.
Clapperton, later on, again visited the Niger from Benin.