On 16 September 1864, Burton and Speke were scheduled to debate the source of the Nile at a meeting of the British Association for the Advancement of Science. On the day before the debate, Burton and Speke sat near each other in the lecture hall. According to Burton's wife, Speke stood up, said "I can't stand this any longer," and abruptly left the hall. That afternoon Speke went hunting on the nearby estate of a relative. He was discovered lying near a stone wall, felled by a fatal gunshot wound from his hunting shotgun. Burton learned of Speke's death the following day while waiting for their debate to begin. A jury ruled Speke's death an accident. An obituary surmised that Speke, while climbing over the wall, had carelessly pulled the gun after himself with the muzzle pointing at his chest and shot himself. Alexander Maitland, Speke's only biographer, concurs.