The governor, having full information concerning those parts through which he had to enter in order to discover the land and relieve the Spaniards, and being supplied with all things necessary for his journey, on the eighteenth of October of the same year ordered the embarkation of the people that were to follow him in the discovery, with the twenty-six horses and mares which had survived the sea voyage; and he ordered them to cross the river Ytabucu and subdue it, and take possession of it in the name of His Majesty, as newly discovered land. He left in the island of St. Catalina one hundred and forty persons, who were to embark and go by sea to the river La Plata, where the port of Buenos Ayres is situated; and he charged Pedro Estropiñan Cabeza de Vaca, whom he left there in the capacity of captain of the said people, that before leaving the island he should supply and furnish the vessel with provisions both for the people he was taking with him, as well as for those in Buenos Ayres; and before his departure he gave many presents to the natives of the island, in order that they might remain, and some of them readily offered their services to accompany the governor and his people, to show the road and be useful in other ways; and their assistance happened to be very handy.