Las Casas relates that when he was making a journey within his diocese, he met one of his missionaries named Francisco Hernandez, who had been for some years living in Yucatan, and had become acquainted with the language. Thinking that this ecclesiastic would be useful for the work of converting the Indians to the faith, he made him his vicar and sent him into the interior to preach amongst the natives. After a lapse of several months he received a letter from the vicar stating that he had been told by one of the principal caciques, that it was known that, anciently, there had arrived in Yucatan twenty strangers. They were dressed in long robes, had sandals upon their feet, and taught religion. It was also mentioned that these men wore long beards,[109] and that they had a leader who was named Cucul-can (Quetzalcoatl). Las Casas concludes by observing that “Certainly the land and kingdom of Yucatan gives us to understand most especial things, and of the greatest antiquity with regard to the grand, admirable and exquisite styles of ancient edifices, and writings of certain characters which are in no other place. Finally, these are secrets which God only knows. (Finalmente, secretos son estos que sólo Dios los sabe).”[110] But the most explicit statements with regard to Quetzalcoatl were those which were given by the chief-priests of the temples raised to his memory at Cholula.[111] They affirmed the tradition of the arrival of strangers of a white race and foreign origin coming by sea in vessels from the east. These strangers were said to have taught the Indians to build monasteries, and maintain seminaries for religious instruction. According to Clavigero, they taught certain natives the methods of arranging the divisions of time and the use of the calendar. The priests also showed the Spaniards some ornaments which they said had been worn by the chief of these strangers. The positive declarations about white people having landed upon the shores of the Mexican Gulf have been carefully investigated. It has been usually considered that they were the result of a myth, or that they were based upon vague traditions relating to events which, if they had any foundation, must have happened at a period exceedingly remote and possibly referred to early migrations from Asia. But it has to be remembered that the facts reported by the caciques and priests invariably related to a period when their tribes were established in Yucatan or Mexico; and the arrival of the strangers was always said to have taken place on the eastern seaboard of those lands. As the Toltecs according to the Indian records were not established there before the sixth century the event, if it occurred, must have happened after that date.