Queen Morgana steals the sheath of Excalibur.

So Queen Morgana went into the chamber where the King lay and he did not waken at her coming. Then Queen Morgana was filled full of hatred and a great desire for revenge, wherefore she said to herself, “I will take Excalibur and his shield and will carry them away with me to Avalon, and my brother shall never see them again.” So she went very softly to where King Arthur lay, and she looked upon him as he slept and perceived that he had Excalibur beside him and that he held the handle of the sword in his hand while he slept. Then Queen Morgana said, “Alas, for this, for if I try to take Excalibur away from him, haply he will awake and he will slay me for my treason.” Then she looked and perceived where the sheath of Excalibur lay at the foot of the couch. So she took the sheath of Excalibur very softly and she wrapped it up in her mantle and she went out thence, and King Arthur did not awaken at her going.

So Queen Morgana came out from the King’s chamber and she said to those in attendance, “Do not waken the King, for he sleepeth very soundly.” Therewith she mounted her horse and went her way from that place.

Now, after a considerable while, King Arthur awoke and he looked for the sheath of Excalibur, but he perceived that it was gone, wherefore he said immediately, “Who hath been here?” They in attendance made answer, “Queen Morgana le Fay had been here and she came in and saw you and went her way without waking you.” Then King Arthur’s heart misgave him, and he said, “I fear me that she hath dealt treacherously with me from the beginning to the end of these adventures.”

Whereupon he arose and summoned all his knights and esquires and mounted his horse for pursuit of Queen Morgana, although he was still passing sick and faint from his sore wounds and loss of blood.

Now, as the King was about ready to depart, Vivien came to him where he was, and she said, “Lord, take me with thee, for if thou dost not do so thou wilt never recover Excalibur his sheath, nor wilt thou ever overtake Queen Morgana le Fay.” And King Arthur said, “Come with me, damsel, in God’s name.” So Vivien went with him in pursuit of Queen Morgana.

Now, by and by, as she fled, Queen Morgana le Fay looked behind her and therewith she perceived that Vivien was with the party of King Arthur, wherefore her heart failed her and she said, “I fear me that I am now altogether ruined, for I have aided that damsel to acquire such knowledge of magic that I shall have no spells to save myself from her counter-spell. But at any rate it shall be that King Arthur shall never have the sheath of Excalibur again for to help him in his hour of need.”

Queen Morgana throweth the sheath of Excalibur into the lake.

Now at that time they were passing beside the margin of a lake of considerable size. So Queen Morgana le Fay took the sheath of Excalibur in both her hands and swung it by its belt above her head and she threw it a great distance out into the water.

Then, lo! a very singular miracle occurred, for there suddenly appeared a woman’s arm out of the water and it was clad in white. And it was adorned with many bracelets. And the hand of the arm catched the sheath of Excalibur and drew it underneath the water and no one ever beheld that sheath again.