H. 6.--With the Druids Diodorus associates two other religiously influential classes amongst the Britons, the Bards [[Greek: bardos]] and the Seers [[Greek: manteis]]. The former present the familiar features of the cosmopolitan minstrel. They sing to harps [[Greek: organôn tais lurais homoiôn]], both fame and disfame. The latter seem to have corresponded with the witch-doctors of the Kaffir tribes, deriving auguries from the dying struggles of their victims (frequently human), just as the Basuto medicine-men tortured oxen to death to prognosticate the issue of the war between Great Britain and the Boers in South Africa. Strabo, in the next generation, also mentions together these three classes, Bards, Seers [[Greek: Ouateis] = Vates] and Druids. The latter study natural science and ethics [[Greek: pros tê phusiologia kai tên êthikên philosophian askousin]]. They teach the immortality of the soul, and believe the Universe to be eternal, "yet, at the last, fire and water shall prevail." H. 7.--Pomponius Mela, who wrote shortly before the Claudian conquest of Britain, says that the Druids profess to know the shape and size of the world, the movements of the stars, and the will of the Gods. They teach many secrets in caves and woods, but only to the nobles of the land. Of this esoteric instruction one doctrine alone has been permitted to leak out to the common people--that of the immortality of the soul--and this only because that doctrine was calculated to make them the braver in battle. In accordance with it, food and the like was buried with the dead, for the use of the soul. Even a man's debts were supposed to pass with him to the shades.