"How, I do not know; but it was done when Colonel Livenza was here to-day, closeted with his Excellency. They were, as perhaps you know, senor, closely associated together." There was a furtive, half eager, half alarmed, and wholly cunning look on Rubio’s face, which sent the thought flashing upon me that he could say a good deal of Quesada’s private matters if he pleased. "I know much more than you think, Senor Rubio. These two were close friends, you say; did they part to-day on friendly terms?" "I was not here, senor," was the guarded reply. But I could read the facts without his help. Livenza had come to demand an explanation, and intended, no doubt, to wreak his revenge on the spot. There had been a quarrel, and probably some kind of tussle, in which this window had been broken. Livenza had for some reason abstained from shooting Quesada there and then; but he had been quick to see that if he left and went round to the back of the house, he could fire at his victim through the broken window, and kill him without anyone suspecting the act. I got some confirmation of this theory by questioning the servant, who had seen his master after Livenza had left the house, and had noticed that he was unusually excited and angry. There was the fact that no sound of a pistol shot had been heard; but the room had double doors and a heavy portiere curtain, and this might well account for such a thing. I was, at any rate, satisfied with my theory, and while I was with Rubio, Mayhew arrived with the official papers placing the police services at my disposal. I showed them to him, and they increased his apprehension. "I shall do all I can to help you, senor," he assured me, nervously. "You will find it safer," said I, significantly. "Have any of Senor Quesada’s papers been removed?" "None," he answered, with a slight start. "Well, then my friend Mr. Mayhew here, of the British Embassy, will remain and see that everything is sealed. And now tell me, do you suspect anyone of this murder?" "It is the work of the cursed Carlists, of course. His Excellency’s life was more than once attempted by them." "Put that idea out of your head. This was a private crime, and we have to bring it home to the murderer. Where is Senorita Castelar?" I put the question abruptly, and looked at him fixedly. He started very uneasily. "She could not do it." "I am perfectly aware of that, but I must know at once where she is. Understand, your future will depend upon your answering me frankly. You know quite well where she is, for you have been Senor Quesada’s instrument in all that business. When you arrested her at the station yesterday, where did you take her, and to what place did you remove her afterwards?" "She was taken to the prison of San Antonio, and afterwards removed by his Excellency’s orders—I don’t know where."