“That explains a lot to you!” Mrs. Clephane exclaimed.

“The explanation isn’t necessary, except to complete the chain of events,” he replied.  “We know the later and essential facts as to the letter.  There is just one earlier circumstance that isn’t clear to me; and while, as I say, it’s immaterial yet I’m curious.  How did the Spencer gang know that I had taken the letter from the cab?”

“Oh!” Mrs. Clephane cried.  “I fancy I can explain.  You know I saw you at the cab.  Well, when they released me, I concluded I’d give them something to think about, and I remarked that Mr. Harleston, of the United States Diplomatic Service, had stopped at the cab, looked inside, and then started the horse out Massachusetts Avenue.  I thought I had told you.”

“You didn’t tell me, but it’s very plain now.  Madeline Spencer inferred the rest and instructed them how to act.  And they came very close to turning the trick.”

“You mean to getting the letter?” she cried.

He nodded.  “I had gone to bed, when something told me to take precautions; I carried the letter across the corridor and gave it to a friend to keep for me until morning.  A short time after, the three men called.”

“Good Heavens!” she breathed.  “What if they had gotten the letter.”

“Unless they knew the key-word, they wouldn’t have been any better off than are we—­I mean than is the United States.”

“I’m France, am I?” she smiled.

“For only this once—­and not for long, I trust,” he replied.

“Amen!” she exclaimed, “Also for ever more.  I’ll be so relieved to be out of it and back to my normal ways that I gladly promise never to try it again.  I’m committed to seeing this affair through and to aiding the French Embassy in whatever way I can, both because I must keep faith with Madame Durrand, and because my inexperience and credulity lost it the letter.  That done, and I’m for—­you, Mr. Harleston!” she laughed.

“And I’m for you always—­no matter whom you’re for, nor what you may do or have done,” he replied.

For just an instant she gave him her eyes; then the colour flamed up and she turned hastily away.

“Sit down, sir,” she commanded—­most adorably he thought; “I had almost forgotten that I have something to tell you.”

“You’ve been telling me a great deal,” he confided.

She shrugged her answer over her shoulder, and peremptorily motioned him to a chair.

“Madame Durrand has been located,” she began.  “The Embassy telephoned me that she is in Passavant Hospital, getting along splendidly; and that she duly wired them of her accident and of my having the letter, with an identifying description of me.  The wire was never received.”

“It was blocked by a present,” he remarked.  “The wire never left the hospital.”

“So the Marquis d’Hausonville said.  He also assured me that the letter was of no immediate importance, and that steps were being taken to have it repeated.”