Major Laing, a Scotchman, who had already, in 1823, distinguished himself by exploring the source of the Rokel river of Sierra Leone (practically locating the source of the Niger and ascertaining its approximate altitude), determined in 1825 to strike out a new departure in the search for Timbuktu. He started from Tripoli, journeyed to Ghadames and the oasis of Twat, and thence rode across the desert to the Niger over a route which may some day be followed by a French trans-Saharan railway. He was attacked on the way by the detestable Tawareq, who left him for dead, bleeding from twenty-four wounds. Still, he recovered, and actually entered Timbuktu on the 18th of August, 1826. Being advised by the people to leave because of their dislike to the presence of a Christian, he started to return across the desert, but was killed at El Arwan, a few marches north of Timbuktu, at the instigation of the Fula king Ahmadu of Masina. French names were scarce in the roll of explorers after the journeys of Brüe and Campagnon at the beginning of the 18th century; though Le Vaillant, as a naturalist, made small but very interesting explorations in South Africa. But in the early part of the 19th century, after the recovery of their Senegalese possessions, Frenchmen resumed the exploration of the Dark Continent. Already, in 1804, Rubault, an official of the Senegal Company, had explored the desert country between the Senegal and the Gambia, and the upper waters of the Senegal. In 1818 Gaspard Mollien discovered the source of the Gambia, and explored Portuguese Guinea. In 1824 and 1825 De Beaufort visited the country of Kaarta to the north-east of the Senegal. Then came René Caillé, who reached Timbuktu and returned thence to Morocco in 1827, a journey discussed for its political importance in Chapter IX. In 1817 a British mission was sent to Ashanti, under the eventual leadership of Thomas Edward Bowdich. Bowdich, who made a treaty with the king of Ashanti, employed the opportunities of intercourse with Hausa, Mandingo, and Moorish merchants at the court of this monarch to collect a quantity of most valuable information as to the course of the Niger, the fate of Mungo Park, the geography, ethnology and languages of the heart of West Africa within the Niger bend. His book, published in 1820, is a valuable work in African anthropology and history.