Narrative of Travels and Discoveries in Northern and Central Africa, in the Years 1822, 1823, and 1824, by Major Denham, Captain Clapperton, and the Late Doctor Oudney. Extending Across the Great Desert to the Tenth Degree of Northern Latitute, and from Kouka in Bornou, to Sackatoo, the Capital of the Fellatah Empire. With an Appendix, Published by Authority of the Right Honourable Earl Bathurst, on of His Majesty's Principal Secretaries of State, and Dedicated by Permission to His Lordship, by Major Dixon Denham, of His Majesty's 17th Regiment of Foot, and Captain Hugh Clapperton, of the Royal Navy, the Survivors of the Expedition