"Morro's flag is down!" came the shout. It was true. A gunner on the noble _Oregon_ had taken careful aim and cut the flagstaff in two. The falling of the Spanish emblem was greeted with a wild cheer. At once the Spaniards tried to put another flag up, but it was some time ere they succeeded, and then it was a tiny affair, hardly visible excepting with a glass. "We'll try for that battery yonder!" exclaimed Caleb, during the height of the bombardment. "I think those fellows have been firing this way ever since they started." He had scarcely spoken when bang! something hit the armor plate directly under their gun, hurling the gunner, Walter, and several others back by the shock. "They've struck us, but the shot didn't pierce our armor," remarked Caleb, calmly, as he got up. "All right, you villains, here's the compliment returned!" And he made his preparations with care. The shot following was the best they had yet placed. It struck into a battery on the west shore of the harbor entrance, ploughed up the foundation of a six-pound gun, and sent the piece flying high into the air. "My, but that was immense!" cried Walter, while Si and the others cheered wildly. "Give them another!" And they did give the battery another, and then a dozen more, until at last the place was silenced, showing that what was left of the gunners had fled. At half-past seven came the order to cease firing, but it was fully twenty minutes later before the last of the warships' guns were discharged. By this time not only the batteries but also old Morro were filled with gaping holes. It is more than likely that if the fleet had sought to enter the harbor at this time it could have done so with comparative ease. The work at the gun had been very hot, and as soon as they were able to do so, Walter and Si scurried to the upper deck to get a bit of fresh air. "It fairly stews the fat out of a fellow," grumbled Si, running the perspiration from his forehead with his forefinger. "I'll bet I'm ten pounds lighter than before this blockade began." "Never mind; it's one of the fortunes of war--" began Walter, when of a sudden a strange whir and a singing sound filled the air. It was a shell, fired from Morro Castle, just as the _Brooklyn_ was turning away. "Look out!" yelled Si, and dropped down, but the words were still on his lips when the shell exploded, sending the fragments flying in all directions. Both boys were struck, and with a groan Walter fell senseless to the deck. CHAPTER XXVIII "THE ENEMY IS ESCAPING!" "Is he dead, surgeon?" "Oh, doctor, he'll live--say he'll live!" Caleb and Si had followed the senseless form of Walter to the sick bay of the warship, the Yankee youth with the blood streaming from a deep cut in his left cheek. Both were in distress for fear their comrade was seriously injured.