The victories of the Dutch fleets in India, Brazil and Peru and their conquest of some of the West Indian Islands, as also England's expansion of her dominions and the growth of her naval power were cause for grave anxiety. Measures of defense and protection became the subject of interminable discussions in the official circles of Madrid and Havana. The governors sent over by the court were urged to multiply their effort to fortify Cuba and insure safety from attacks by covetous enemies. D. Francisco Gelder, Field-marshal and Knight of Calatravas, succeeded Villalba and was inaugurated on the twenty-eighth of March, 1653. One of his first official acts was to sever communication with Santiago and Bayamo, for these two towns were at that time ravaged by the same epidemic from which Havana had suffered. His preventative measure set an example which was soon after followed by the authorities of Trinidad, Sancti Spiritus, Puerto Principe, Baracoa and Remedios, and the spreading of the epidemic being checked, the island soon returned to normal conditions. Like other governors before him, Gelder showed a deplorable leniency towards those elements of the population that carried on contraband traffic with negroes. But he displayed great energy in the persecution of pirates. During his administration Captain Rojas de Figuerosa captured the island of Tortuga, which had been a formidable base of corsair operations. The news of this exploit caused great rejoicing in Havana and was celebrated by a Te Deum under the direction of Bishop Torre. Gelder also devised a plan to protect Havana from invasion by land. He proposed to open a canal from the extreme interior bay running north and extending to the sea, which would have surrounded the town by water and make it practically safe. But the suggestion did not seem to meet with approval. Before any other plans could be drafted, he died of apoplexy, on the twenty-third of June, 1654, and in the interval between his death and the arrival of his successor from Spain, the government was administered by the Regidor D. Ambrosio de Soto and D. Pedro Garcia Montanes, commandant of Morro.