Cryptogram from Frankenstein; or, the modern prometheus, chapter 24

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My life, as it passed thus, was indeed hateful to me, and it was during sleep alone that I could taste joy. O blessed sleep! Often, when most miserable, I sank to repose, and my dreams lulled me even to rapture. The spirits that guarded me had provided these moments, or rather hours, of happiness that I might retain strength to fulfil my pilgrimage. Deprived of this respite, I should have sunk under my hardships. During the day I was sustained and inspirited by the hope of night, for in sleep I saw my friends, my wife, and my beloved country; again I saw the benevolent countenance of my father, heard the silver tones of my Elizabeth's voice, and beheld Clerval enjoying health and youth. Often, when wearied by a toilsome march, I persuaded myself that I was dreaming until night should come and that I should then enjoy reality in the arms of my dearest friends. What agonising fondness did I feel for them! How did I cling to their dear forms, as sometimes they haunted even my waking hours, and persuade myself that they still lived! At such moments vengeance, that burned within me, died in my heart, and I pursued my path towards the destruction of the dæmon more as a task enjoined by heaven, as the mechanical impulse of some power of which I was unconscious, than as the ardent desire of my soul.