Bacon's prose, beyond the region of essays and of science, may best be studied in his "Reign of Henry VII," the fruit of a few months' labour, after his banishment to the country, in 1621. He had no access to manuscripts of the period, except in copies made for him in the great collection of Sir Robert Cotton, now in the British Museum. The printed books concerning the reign, those of Polydore Virgil, Holinshed (translating Polydore), Stowe, and Speed, led Bacon into some mistakes about facts. But the book is lucid and sagacious; the character of the king is clearly depicted, without favour or deliberate fault-finding. The study of Perkin Warbeck is full of subtle interest. "Himself with long and continued counterfeiting and with often telling a lie was turned, by habit, almost into the thing he seemed to be, and from a liar to a believer." Ford makes Henry VII express the same opinion in his tragedy of "Perkin Warbeck". Bacon treats the strange career of Perkin in terms of the Stage, speaks of the prompter with his prompt-book, and, in the last Act, says, "therefore now, like the end of a play, a great number came upon the stage at once". The nature of the statecraft of Henry VII, not very apprehensive or forecasting of future events, afar off, "but an entertainer of Fortune by the day," is admirably analysed. "I have not flattered the king," says Bacon in his dedication to Charles, Prince of Wales, "but took him to life as well as I could, sitting so far off, and having no better light." Henry's attempt to secure the canonization of Henry VI is amusingly described. Cardinals were set to examine that poor prince's career, "but it died under the reference. The general opinion was that Pope Julius was too dear, and that the king would not come to his rates." But Bacon holds that the Pope did not wish to cheapen saintliness, and chose to "keep a distance between innocents and Saints". The virtues of Henry VI had not the necessary quality of being heroic.