Among the manuscripts which seem to have belonged to Ixtlilxochitl was the one known in our day under the designation given to it by Brasseur de Bourbourg, _Codex Chimalpopoca_,[883] in honor of Faustino Chimalpopoca, a learned professor of Aztec, who assisted Brasseur in translating it. The anonymous author had set to himself the task of converting into the written native tongue a rendering of the ancient hieroglyphics, constituting, as Brasseur says, a complete and regular history of Mexico and Colhuacan. He describes it in his _Lettres à M. le duc de Valmy_ (_lettre seconde_)—the first part (in Mexican) being a history of the Chichimecas; the second (in Spanish), by another hand, elucidating the antiquities—as the most rare and most precious of all the manuscripts which escaped destruction, elucidating what was obscure in Gomara and Torquemada. Brasseur based upon this MS. his account of the Toltec period in his _Nations Civilisées du Mexique_ (i. p. lxxviii), treating as an historical document what in later years, amid his vagaries, he assumed to be but the record of geological changes.[884] A similar use was made by him of another MS., sometimes called a Memorial de Colhuacan, and which he named the _Codex Gondra_ after the director of the Museo Nacional in Mexico.[885] Brasseur says, in the _Annales de Philosophie Chrétienne_, that the _Chimalpopoca MS._ is dated in 1558, but in his _Hist. Nat. Civ._, i. p. lxxix, he says that it was written in 1563 and 1579, by a writer of Quauhtitlan, and not by Ixtlilxochitl, as was thought by Pichardo, who with Gama possessed copies later owned by Aubin. The copy used by Brasseur was, as he says, made from the MS. in the Boturini collection,[886] where it was called _Historia de los Reynos de Colhuacan y México_,[887] and it is supposed to be the original, now preserved in the Museo Nacional de México. It is not all legible, and that institution has published only the better preserved and earlier parts of it, though Aubin’s copies are said to contain the full text. This edition, which is called _Anales de Cuauhtitlan_, is accompanied by two Spanish versions, the early one made for Brasseur, and a new one executed by Mendoza and Solis, and it is begun in the _Anales del Museo Nacional_ for 1879 (vol. i.).[888] The next after Ixtlilxochitl to become conspicuous as a collector, was Sigüenza y Gongora (b. 1645), and it was while he was the chief keeper of such records[889] that the Italian traveller Giovanni Francesco Gemelli Carreri examined them, and made some record of them.[890] A more important student inspected the collection, which was later gathered in the College of San Pedro and San Pablo, and this was Clavigero,[891] who manifested a particular interest in the picture-writing of the Mexicans,[892] and has given us a useful account of the antecedent historians.[893] [Illustration: CLAVIGERO. After a lithograph in Cumplido’s Mexican edition of Prescott’s _Mexico_, vol. iii.]