Some time in the year 1452 the King, who was then in Lisbon, charged him with the book which constitutes his chief title to fame, owing to the importance of its subject, and the historical fidelity and literary skill that distinguish its presentment, namely, the _Chronica de Guiné_, or, as it might be called, the _Life and Work of Prince Henry the Navigator_. From the subscript we find it was written in the Royal Library, and finished there on February 18th, 1453. Azurara sent it to the King, five days afterwards, with a letter which has fortunately been preserved, since it shows how friendly and even familiar were the relations subsisting between them, and how these were maintained by a regular correspondence. It appears that Affonso had urged Azurara to obtain all the information possible about the life and work of D. Henrique, and, this done, to write as best he could, "alleging a dictum of Tully, that it sufficeth not for a man to do a good thing but rather to do it well". Then the letter proceeds, addressing the King: "For it seemed to you that it would be wrong if some example of such a saintly and virtuous life were not to remain, not only for the sake of the Princes who after your time should possess these realms, but also for all others of the world who might become acquainted with his history, by reason of which his countrymen might have cause to know his sepulchre, and perpetuate Divine Sacrifices for the increase of his glory, and foreigners might keep his name before their eyes, to the great praise of his memory."[23] [Footnote 23: This letter defines the scope of the book, which was not meant to be a general history of the Portuguese expeditions and discoveries. It is printed in Santarem's edition of the _Chronica de Guiné_, and precedes his Introduction.] The following is a summary of the contents of the _Chronicle_:-- Azurara begins (Chapter I) by some reflections on well-doing and gratitude, the conclusion to which he illustrates by quotations, and then goes on to tell the origin of his work, which lay in the King's desire that the great and very notable deeds of D. Henrique should be remembered, and that there should be an authorised memorial of him, even as there was in Spain of the Cid, and in Portugal itself of the Holy Constable, Nun' Alvarez Pereira.[24] The Chronicler justifies his task by summing up the profits that had accrued from the Prince's efforts--firstly, the salvation of the souls of the captives taken by the Portuguese in their expeditions; secondly, the benefit which their services brought to their captors; and thirdly, the honour acquired by the fatherland in the conquest of such distant territories and numerous enemies. [Footnote 24: This charming old chronicle of the life of the noblest and most sympathetic figure in Portuguese annals was written anonymously, and first printed in 1526.]