I believed now I comprehended how it had occurred, all except the mysterious unlocking of the door at the foot of the stairs, and this fellow in our uniform that haunted the ell.  To make certain I retained the key, I took it out, and fitted it into the lock.  Still there might be a duplicate, and as for the soldier, I was hardly half convinced of his reality.  Billie had acted quickly, under the inspiration of discovery, and all the circumstances had conspired to make her escape from the house easy.  Miles had withdrawn his men on my orders, and we were all grouped together in the front hall.  She had simply slipped down these back stairs, used a duplicate key, passed through the kitchen unobserved, and out into the garden.  Where then?  To the stable, without doubt, and, mounted, into Chambers’ lines, taking her news to the highest officer she could reach.  We would hear from it presently,—­strange if not even already some of those troops were wheeling to invest the house.  I called back up the stairs,

“Conroy, send Major Hardy down here.”

The Confederate appeared almost instantly, his eyes anxiously surveying the room.

“Have you found my girl?”

“No, but I have satisfied myself as to where she is.  Without doubt she came down those stairs, and out this door, while we were in the front hall.  A battle-line is a rough place for a woman, and I am going to turn you out now to see if you cannot find and protect her.  One of you men take down that bar.”

The major stared at me, and then extended his hand.

“You—­you don’t suppose I sent her?”

“Oh, no, you have been most honorable.  There is no reason why I should hold you here; the others have gone, and you may be of assistance to Miss Willifred.  It is bound to be lively enough for us in here presently without prisoners to look after.”

“But you have not accepted my hand, Lieutenant Galesworth.  I wish to feel that we part friends.”

“We certainly do,” I returned heartily, grasping his fingers.  “And—­and I may never see your daughter again.  There is scarcely a possibility that I ever shall.  Tell her that I respect her loyalty to the South.”

He stood looking directly into my eyes, grasping both my hands.

“You mean to remain here, defending the house?”

“While there is a man left alive.”

“It is a pity—­in my judgment; not war, but a useless sacrifice.”

“Yet a soldier’s duty, Major—­obedience to orders.”

He bowed, choking in the throat, as he lifted his hat.  With one glance at the silent soldier holding open the door he passed out.  Then he turned, hat still in hand, and glanced back.

“You may feel assured I will deliver your message, sir,—­good-bye.”

* * * * *

The broad hallway ran from the front of the house to the kitchen ell, and I could see its entire length.  Several men were clustered at the other end, peering out through the narrow panes of glass either side the front door, and one came running toward me.  It was the Irish sergeant.