Estuban said: "De Socotra must be arrested before he gets on the train."
Greg thought anxiously of Amy. "That won't do you any good," he said quickly. "You couldn't prove in advance that he intended to impersonate another."
"I could prove the murder."
"Not without Señorita de Socotra. And she won't testify against him."
"Then must he go free?" cried Estuban stormily.
"No. Let us get the little black book from him and he is helpless. You could carry that to the President yourself."
"How do you purpose getting hold of it?"
"I don't know yet. I have four hours before train time. I'll find a way. At least I know now that it is on his person."
"Go ahead and see what you can do. But if you fail I must hold myself free to act. I will be on the train on which he travels to Washington."
"But he must know you," said Greg.