In spite of weakness Dixie straightened up. Her lips parted and she reached involuntarily toward the pocket that held her Secret Service Commission. But the impulse was checked, for the orders she had received months before flashed through her throbbing brain:
"Work into the trust of the Germans. Tell no one.
"W.J. Flynn."
"Why do you accuse me?" she asked.
"Miss Mason, what else could one do? We arrive in time to see the explosion, the workers running out, and——"
Dixie leaned forward.
"The workers, are they safe?" she asked eagerly.
"Most of them. Some are injured. I am glad you at least warned them."
"Thank you. Now would you mind releasing my hand?"
Grant looked at her in wonder. Would he ever fathom this mystery girl? Could it be possible that he had made a mistake? But in contraversion to this thought came the memory of her constant association with the Germans most active in promoting the interests of their government; her frequent appearances with Von Lertz and Madam Stephan. And what possible motive could have brought her to this scene and placed her in such a situation?
"Miss Mason, I can say nothing except that a watchman told me of having seen a girl running toward the power house a moment before the explosion came. I must put you under arrest. The evidence is absolute and I can do nothing else."