Having collected a volume of his fugitive verses, principally composed in prison, he published it with a dedication to the princesses, the duchess of Urbino and Leonora; but the latter lived not to receive this mournful proof of the fidelity of his gratitude, if not of his love. She died, after a long illness, in 1581, aged 43 years. Tasso enquired earnestly after her during her sickness, and offered to do any thing in the power of his muse to beguile that part of her suffering which song might soothe, while patiently bearing the rest, for which there was no relief but from Heaven. After her death he became mute on that theme, which most of his biographers would fain prove to have been the real though covert one of many an amorous effusion among his sonnets and lyrics. "Great griefs are silent." Among his wild imaginations, Tasso thought himself haunted in his prison by a sprite--something akin to our old English Robin-good-fellow--who (probably in the very person of his knavish attendant) played all manner of petty mischievous pranks to plague him. One extract from a letter on this subject will show how little command of his reason he had at this time. He says, "The little thief has stolen from me many crowns, I know not what number--for I do not, like misers, keep an account of them--but perhaps they may amount to twenty. He turns all my hooks topsy-turvy, opens my chests, and steals my keys, so that I can keep nothing. I am unhappy at all times, especially during the night, nor _do I know if my disease be frenzy, or what is its nature._" Far more frightful visitations he complains of during this dreadful interval, all which seem to prove a lamentable derangement of intellect, of which he was himself sometimes so conscious, that he rouses all his powers of reasoning to convince himself that he has not really lost his wits. To a friend he writes--"I cannot defend any thing from my enemies, nor from the devil, _except my will_, with which I will never consent to learn any thing from him or his followers, or have any _familiarity with him or with his magicians._ * * * * Amidst so many terrors and pains, there appeared to me in the air the image of the glorious Virgin, with her Son in her arms, encircled with clouds of many colours, so that I ought by no means to despair of her grace. _And though this might be an illusion, because I am frenetic_,--troubled with various phantasms, and full of infinite melancholy,--yet, by the grace of God, I can sometimes _cohibere assensum_ (withhold my assent), which, as Cicero says, being the act of a sound mind, I am inclined to believe it was a miracle of the Virgin."--This vision he celebrates in one of his most brilliant sonnets, and also in an elegant madrigal, ascribing to her grace the marvellous cure of his mental affliction.