"Oh! what a glorious reverie you have dissipated!" exclaimed Wagner. "Fulfill but one tenth part of that delightful dream----" "I will fulfill it all!" interrupted the stranger: then, producing a small vial from the bosom of his doublet, he said, "Drink!" The old man seized the bottle, and speedily drained it to the dregs. He immediately fell back upon the seat, in a state of complete lethargy. But it lasted not for many minutes; and when he awoke again, he experienced new and extraordinary sensations. His limbs were vigorous, his form was upright as an arrow; his eyes, for many years dim and failing, seemed gifted with the sight of an eagle, his head was warm with a natural covering; not a wrinkle remained upon his brow nor on his cheeks; and, as he smiled with mingled wonderment and delight, the parting lips revealed a set of brilliant teeth. And it seemed, too, as if by one magic touch the long fading tree of his intellect had suddenly burst into full foliage, and every cell of his brain was instantaneously stored with an amount of knowledge, the accumulation of which stunned him for an instant, and in the next appeared as familiar to him as if he had never been without it. "Oh! great and powerful being, whomsoever thou art," exclaimed Wagner, in the full, melodious voice of a young man of twenty-one, "how can I manifest to thee my deep, my boundless gratitude for this boon which thou hast conferred upon me!" "By thinking no more of thy lost grand-child Agnes, but by preparing to follow me whither I shall now lead thee," replied the stranger. "Command me: I am ready to obey in all things," cried Wagner. "But one word ere we set forth--who art thou, wondrous man?" "Henceforth I have no secrets from thee, Wagner," was the answer, while the stranger's eyes gleamed with unearthly luster; then, bending forward, he whispered a few words in the other's ear. Wagner started with a cold and fearful shudder as if at some appalling announcement; but he uttered not a word of reply--for his master beckoned him imperiously away from the humble cottage. CHAPTER I. THE DEATH-BED--THE OATH--THE LAST INJUNCTIONS. Our tale commences in the middle of the month of November, 1520, and at the hour of midnight. In a magnificently furnished chamber, belonging to one of the largest mansions of Florence, a nobleman lay at the point of death. The light of the lamp suspended to the ceiling played upon the ghastly countenance of the dying man, the stern expression of whose features was not even mitigated by the fears and uncertainties attendant on the hour of dissolution. He was about forty-eight years of age, and had evidently been wondrously handsome in his youth: for though the frightful pallor of death was already upon his cheeks, and the fire of his large black eyes was dimmed with the ravages of a long-endured disease, still the faultless outlines of the aquiline profile remained unimpaired.