In the armed conflict which followed, the most striking and effective operations were on the sea. In anticipation of the war, Commodore Dewey, in command of the Asiatic station, had been instructed as early as February to keep his squadron at Hongkong, coaled, and ready, in event of a declaration of hostilities, to begin offensive operations in the Philippine Islands. The battleship _Oregon_, then off the coast of Washington, was ordered to make the long voyage around the Horn, which has now become famous in the annals of the sea. At the outbreak of the war, Rear Admiral Sampson, in charge of the main squadron at Key West, was instructed to blockade important stretches of the coast of Cuba and to keep watch for the arrival of the Spanish fleet, under Admiral Cervera, which was then on the high seas, presumably bound for Cuba. The first naval blow was struck by Admiral Dewey, who had left Chinese waters on receiving news of the declaration of war and had reached Manila Bay on the evening of April 30. Early the following morning he opened fire on the inferior Spanish fleet under the guns of Cavite and Manila, and within a few hours he had destroyed the enemy's ships, killed nearly four hundred men, and silenced the shore batteries without sustaining the loss of a single man or suffering any injuries to his own ships worthy of mention. News of this extraordinary exploit reached the United States by way of Hongkong on May 6, and the hero of the day was, by popular acclaim, placed among the immortals of our naval history. While celebrating the victory off Manila, the government was anxiously awaiting the arrival of the Spanish fleet in American waters which were being carefully patrolled. In spite of the precautions of Admiral Sampson, Cervera was able to slip into the harbor of Santiago on May 19, where he was immediately blockaded by the American naval forces. An attempt was made to stop up the mouth of the harbor by sending Lieutenant Richmond P. Hobson to sink a collier at the narrow entrance, but this spectacular move, carried out under a galling fire, failed to accomplish the purpose of the projectors, and Hobson and his men fell into the hands of the Spaniards.