Legends of Charlemagne by Thomas Bulfinch

In the long flight which Rogero took on the back of the Hippogriff he was carried over land and sea, unknowing whither. As soon as he had gained some control over the animal he made him alight on the nearest land. When he came near enough to earth Rogero leapt lightly from his back, and tied the animal to a myrtle-tree. Near the spot flowed the pure waters of a fountain, surrounded by cedars and palm-trees. Rogero laid aside his shield, and, removing his helmet, breathed with delight the fresh air, and cooled his lips with the waters of the fountain. For we cannot wonder that he was excessively fatigued, considering the ride he had taken. He was preparing to taste the sweets of repose when he perceived that the Hippogriff, which he had tied by the bridle to a myrtle-tree, frightened at something, was making violent efforts to disengage himself. His struggle shook the myrtle-tree so that many of its beautiful leaves were torn off, and strewed the ground.

A sound like that which issues from burning wood seemed to come from the myrtle-tree, at first faint and indistinct, but growing stronger by degrees, and at length was audible as a voice which spoke in this manner: "O knight, if the tenderness of your heart corresponds to the beauty of your person, relieve me, I pray you, from this tormenting animal. I suffer enough inwardly without having outward evils added to my lot."