A beginning was now made of the harsh oppression which was soon to cause the entire disappearance of the native race. A quarterly tribute was imposed on every Indian above the age of fourteen. Those who lived in the auriferous region of the Cibao were obliged to deliver as much gold dust as could be held in a small bell, others were to give twenty-five pounds of cotton. Many natives fled to the mountains to escape the onerous tax and new settlements were established by the Spaniards. The enemies of Columbus had in the meantime been sufficiently successful in Spain to cause one de Aguado to be sent out with the object of investigating conditions in the colony. His conduct from the very first was so arrogant that the admiral determined to return at once to justify himself before the court. On March 10, 1496, he embarked for Spain, leaving his brother Bartholomew as governor of the colony. Before his departure the news arrived of the discovery of several rich gold mines in the southern part of the island. They were found by a soldier named Miguel Diaz, who having fled to the wilderness to escape punishment for wounding a comrade, had established conjugal relations with an Indian woman near the present site of Santo Domingo City. Noticing that her consort was tiring of her, the lady tried to retain him by revealing the existence of gold deposits in the region; and Diaz promptly secured his pardon and promotion by reporting the find to Isabela. The romance had a sad ending, for the Indian, shocked at the cruel treatment accorded her countrymen by the Spaniards who came to the place, abandoned her husband and children and disappeared in the forest. On arriving in Spain, Columbus wrote his brother to found a town on the south coast at the mouth of the Ozama. Bartholomew Columbus immediately set out to select a site and on August 4, 1496, laid the first stone of the new city on the left bank of the Ozama, calling it Nueva Isabela, in honor of the queen. The name was afterwards changed to Santo Domingo in honor, so tradition has it, of the saint to whom the day of its foundation was dedicated. As the location of this city was much healthier than that of fever-ridden Isabela on the north coast, the settlers in an ever increasing stream removed to the new town which flourished as the other decayed, until after a few years Isabela was entirely abandoned. The only vestiges now remaining of it are a few ruined foundation walls and shapeless heaps of stone overgrown with rank tropical vegetation.