"This is sure enough tough luck," was Billie's comment as he helped the horse to his feet and examined the wound. "It will lay him up for a week." He took the horse by the bridle and led him slowly back toward the Custom House, where he reported to an officer and hunted up Adrian. "What had we better do now?" he asked. "I'd like to find a place to tend to my horse." "The fighting seems about over," was Adrian's reply, "and I reckon the horse will be given attention by some one." "Oh, I don't want to make any trouble, Ad! If nobody objects, suppose we go hunt a stable." They were about to leave when a sergeant stopped them. "You're to follow me to the Captain," he said. "Here," to a marine who stood by, "take charge of these horses and see that the lame one is cared for." "I wonder if they will take our horses away from us?" muttered Adrian as they followed the sergeant. "Give it up. I wonder what he wants of us?" It did not take them long to find out. "Are you the boys that brought the messages from Lieutenant Blunt?" asked Captain Rush. "Yes, sir." "Will you undertake another mission?" "With pleasure," replied Adrian. "Same here, sir," from Billie, "but my horse has been wounded." "That's bad. However, I guess we can find another." "Sure, sir. I can borrow Don's." "Who is Don?" "He's the other one of us, sir. He is still out with Lieutenant Blunt." "Well," said the Captain, "either two of you will do. What I want is to find out to just what point the Mexican army is falling back. Do you think you can find out?" "Sure." "Very well. My compliments to Lieutenant Blunt and give him this order. He will pass two of you through the lines. The other can remain with him. Sergeant, their horses." Five minutes later, both astride Adrian's horse and leading the other, they appeared at the outpost and delivered the order. "Which two shall it be?" laughed the lieutenant as he looked the boys over. "I guess it will have to be Adrian and Don," replied Billie ruefully. "I've had glory enough for one day. The insult to the flag has been avenged and the Stars and Stripes are floating over Vera Cruz." "I think it's only fair that Don, as you call him, should share in the adventure," said the lieutenant, "and the sooner you go the better. It is almost sundown now." Then as Donald and Adrian started on their mission: "Success to you and report here when you return." "Is there any place near here where I can care for my horse?" asked Billie as soon as the others had passed out of sight. "Why, yes. There are stables in almost any of these houses. Here, try this one," and the lieutenant indicated the one before which they were standing. Billie knocked on the big door, but there was no reply. "Knock louder," laughed the lieutenant. "Use your boot." Billie used his foot and with such vigor that the gate flew open. When no one appeared to answer his summons, he stuck his head inside the patio and called lustily.