Continued Conflicts with the Dutch.--The Dutch, too, from time to time showed themselves in Manila. In 1646 a squadron attacked Zamboanga, and then came north to Luzon. The Spanish naval strength was quite unprepared; but two galleons, lately arrived from Acapulco, were fitted with heavy guns, Dominican friars took their places among the gunners, and, under the protection of the Virgin of the Rosary, successfully encountered the enemy. A year later a fleet of twelve vessels entered Manila Bay, and nearly succeeded in taking Cavite. Failing in this, they landed in Bataan province, and for some time held the coast of Manila Bay in the vicinity of Abucay. The narrative of Franciscan missions in 1649, above cited, gives town after town in southern Luzon, where church and convent had been burned by the Moros or the Dutch. The Abandonment of Zamboanga and the Moluccas.--The threat of the Dutch made the maintenance of the presidio of Zamboanga very burdensome. In 1656 the administration of the Moluccas was united with that of Mindanao, and the governor of the former, Don Francisco de Esteybar, was transferred from Ternate to Zamboanga and made lieutenant-governor and captain-general of all the provinces of the south. Six years later, the Moluccas, so long coveted by the Spaniards, and so slowly won by them, together with Zamboanga, were wholly abandoned, and to the Spice Islands the Spaniards were never to return. This sudden retirement from their southern possessions was not, however, occasioned by the incessant restlessness of the Moros nor by the plottings of the Dutch. It was due to a threat of danger from the north. Koxinga the Chinese Adventurer.--In 1644, China was conquered by the Manchus. Pekin capitulated at once and the Ming dynasty was overthrown, but it was only by many years of fighting that the Manchus overcame the Chinese of the central and southern provinces. These were years of turbulence, revolt, and piracy. More than one Chinese adventurer rose to a romantic position during this disturbed time. One of these adventurers, named It Coan, had been a poor fisherman of Chio. He had lived in Macao, where he had been converted to Christianity, and had been a cargador, or cargo-bearer, in Manila. He afterwards went to Japan, and engaged in trade. From these humble and laborious beginnings, like many another of his persistent countrymen, he gained great wealth, which on the conquest of the Manchus he devoted to piracy. His son was the notorious Kue-Sing, or Koxinga, who for years resisted the armies of the Manchus, and maintained an independent power over the coasts of Fukien and Chekiang. About 1660 the forces of the Manchus became too formidable for him to longer resist them upon the mainland, and Koxinga determined upon the capture of Formosa and the transference of his kingdom to that island.