Several demonstrations occurred on the coasts of Cuba and Puerto Rico in preparation for the larger event. On May 13 the North Atlantic Squadron shelled San Juan de Puerto Rico. On May 30 Commodore Schley's squadron bombarded the forts guarding the mouth of Santiago Harbor. Neither attack had any material result. It was evident that well-ordered land operations were indispensable to achieve a decisive advantage. The next act in the war thrilled not alone the hearts of our countrymen but the world by its exceptional heroism. On the night of June 3 Lieutenant Hobson, aided by seven devoted volunteers, blocked the narrow outlet from Santiago Harbor by sinking the collier Merrimac in the channel, under a fierce fire from the shore batteries, escaping with their lives as by a miracle, but falling into the hands of the Spaniards. It is a most gratifying incident of the war that the bravery of this little band of heroes was cordially appreciated by the Spanish admiral, who sent a flag of truce to notify Admiral Sampson of their safety and to compliment them on their daring act. They were subsequently exchanged July 7. By June 7 the cutting of the last Cuban cable isolated the island. Thereafter the invasion was vigorously prosecuted. On June 10, under a heavy protecting fire, a landing of 600 marines from the Oregon, Marblehead, and Yankee was effected in Guantanamo Bay, where it had been determined to establish a naval station. This important and essential port was taken from the enemy, after severe fighting, by the marines, who were the first organized force of the United States to land in Cuba. The position so won was held despite desperate attempts to dislodge our forces. By June 16 additional forces were landed and strongly in-trenched. On June 22 the advance of the invading army under Major-General Shafter landed at Daiquiri, about 15 miles east of Santiago. This was accomplished under great difficulties, but with marvelous dispatch. On June 23 the movement against Santiago was begun. On the 24th the first serious engagement took place, in which the First and Tenth Cavalry and the First United States Volunteer Cavalry, General Young's brigade of General Wheeler's division, participated, losing heavily. By nightfall, however, ground within 5 miles of Santiago was won. The advantage was steadily increased. On July 1 a severe battle took place, our forces gaining the outworks of Santiago; on the 2d El Caney and San Juan were taken after a desperate charge, and the investment of the city was completed. The Navy cooperated by shelling the town and the coast forts.