As the light came, Donald, peering through a crack in the stable, had seen a man climbing up the side of the house toward the roof. Without a moment's hesitation he fired and the man dropped, shot through the right hand. But the shot was Donald's undoing. The flash of his gun was detected and half a dozen men rushed his hiding place and took him prisoner. He was at once taken before the captain of the band and questioned as to the number of defenders and as to the whereabouts of Gen. Blanco. To all the questions Donald gave an evasive answer. "If you will tell me where Gen. Blanco is," said the captain, "I will give you your freedom." "That's easy," was Donald's reply. "He is with Gen. Carranza." "I don't believe it." "Well, I can't help that, nor does what you believe make any difference. It is the truth and what you may believe has nothing whatever to do with it." The captain scowled. "Who is it then, that is defending the house?" "Americans. You had better let us go, or it will be the worse for you. We had a safe conduct from Gen. Huerta, but we were betrayed." "If I had my way," said the captain, "I'd shoot every American in the whole of Mexico." "I don't see why," from Donald. "We have nothing against you." "Take him away," ordered the captain, "and see that he does not escape. Now let us capture the others." There was a rush for the house as Donald was led back to the stable. Billie and Mr. Black heard them coming. "Go to the roof," commanded Mr. Black, speaking to the two females, "and keep yourselves and the little girl out of sight. We will hold them back here as long as we can and then we will also come to the roof." The command had hardly been obeyed than the Mexicans began to crowd up the stairs. They were met with shot after shot, but at last all the weapons were empty. "Run for the roof," said Mr. Black as he arose to his feet and with his heavy boot kicked a head which was just coming up the stairs. Billie obeyed and a minute later the fugitives had gathered upon the last place of safety left. "If we only had some ammunition," moaned Billie. "Can't we do something?" Then, as in answer to his own query, he picked up a twelve-pound cannon ball that lay on the roof and, raising it above his head with both hands, hurled it through the opening upon those below. This unexpected attack caused the besiegers to draw back, but only for a moment. Then they came on again. In his desperation, Mr. Black, with almost superhuman strength, picked up the cannon itself, just as Billie had picked up the ball, and hurled it down the stairs. Half a dozen men fell beneath its weight, while the others, frightened at such an exhibition of strength, fell back in dismay. A shout from the captain urged them forward, but ere they could gather their courage for another rush there came the sound of a volley in the patio below and a minute later Adrian rushed up the stairs, followed by Captain Lopez and a squad of his soldiers.