On April 30, Dewey’s lookouts caught sight of Luzon, the main Philippine island. That night, under cover of darkness and with the lights aboard the U.S. warships extinguished, the squadron slipped by the defensive guns of Corregidor Island and into Manila Bay.
After dawn, the Americans located the Spanish fleet, a group of out-of-date warships anchored off the Cavite naval station. The U.S. fleet, in comparison, was well-armed and well-staffed, largely due to the efforts of the energetic assistant secretary of the Navy, Theodore Roosevelt (1858-1919), who had also selected Dewey for the command of the Asiatic squadron.
At around 5:40 a.m., Dewey turned to the captain of his flagship, the Olympia, and said, “You may fire when ready, Gridley.” Two hours later, the Spanish fleet was decimated, and Dewey ordered a pause in the fighting. He met with his captains and ordered the crews a second breakfast. The surviving Spanish vessels, trapped in the little harbor at Cavite, refused to surrender, and late that morning fighting resumed. Early that afternoon, a signal was sent from the gunboat USS Petrel to Dewey’s flagship announcing that the enemy has surrendered.
Spanish losses were estimated at more than 370 troops, while American casualties were fewer than 10.