The influence of the supernatural appears in the very beginning of the “Morte d’Arthur,” and throughout we trace its controlling effect upon the incidents of the story.  It is by the help of Merlin’s magic that King Uther Pendragon slays the Duke of Cornwall, and assuming the likeness of his rival, obtains possession of his wife Igraine, “a faire ladye, and a passing wyse,” from which union Arthur is born.  On the death of Uther, when the chief nobles and knights are summoned to London by the Archbishop of Canterbury to choose a new king, it is Merlin’s art which discovers to them a sword imbedded in a great rock in the churchyard of St. Paul’s bearing the inscription:  “Whoso pulleth this sword out of this stone and anvil, is rightwise king born of all England”; and it is by the same supernatural aid that the stripling Arthur, whose birth is unknown, fulfils the task which all had essayed in vain.  By the friendly influence of Merlin, Arthur receives his famous sword Excalibur from the hands of the Lady of the Lake, with the scabbard whose wearer can lose no blood; he defeats with great slaughter the hosts of the eleven kings who dispute his throne; and obtains in marriage the celebrated Guenever, who brings him in dowry the Table Round.  But Merlin, who could do so much for others, had the power only to foresee, and not to avert, his own impending fate.  Enamoured of a fickle damsel, who soon tires of his love, the great enchanter discloses his secrets to her, and with a sad farewell and final advice to Arthur, he suffers himself to be imprisoned forever in the rock which his own magic had wrought, by the spell which he had intrusted to his treacherous mistress.  The friendly arts of Merlin are succeeded by the machinations of the malicious fairy Morgana, and the watchful care of the the Lady of the Lake.  To excite the childlike wonder of his readers, the romancer turns knights to stone, or makes them invisible; he introduces enchanted castles, vessels that steer themselves, and the miraculous properties of the Saint Greal, Arthur and Tristram fight with dragons and giants.  The loves of Tristram and Isoud arise from the drinking of an amorous potion.  The chastity of knight and damsel is determined by the magic horn, whose liquor the innocent drink, but the guilty spill; and by the enchanted garland, which blooms on the brow of the chaste, but withers on that of the faithless.  Inventions such as these were regarded as facts, or at least as possible occurrences, by the readers of romantic fiction.  Men believed what they were told, and to doubt, to inquire were intellectual efforts which they knew not how to make, and which all the influences of their life opposed their making.  There were no fictions in the romances more improbable than the accounts of foreign parts brought back by travellers.  Sir John of Mandeville was not doubted when he wrote that he had met with a race of men who had only one eye, and that in the middle of the forehead,