"A certain doc.u.ment?" I said, looking intently at the speaker.

"Exactly, colonel."

"Which Swartz has?"

"Precisely, colonel."

"And which he stole from the papers of Colonel Darke on the night of Mohun's combat with Darke, in the house near Carlisle?"

Mr. Nighthawk looked keenly at me, in turn.

"Ah! you know that!" he said, quickly.

"I saw him steal it, through the window, while the woman's back was turned."

"I am deeply indebted to you, colonel," said Mr. Nighthawk, gravely, "for informing me of this fact, which, I a.s.sure you, is important.

Swartz swore to me that he had the paper, and had procured it in that manner, but I doubted seriously whether he was not deceiving me. He is a _very_ consummate rascal, knows the value of that doc.u.ment, and my appointment with him to-night is with an eye to its purchase from him."

"Do you think he will come?"

"I think so. He would sell his soul for gold."

"And that woman? he seems to be her friend."

"He would sell _her_ for _silver_!"

After uttering which _bon mot_, Mr. Nighthawk smiled.

This man puzzled me beyond expression. His stealthy movements were strange enough--it was singular to meet him in this lonely house--but more singular still was the business which had brought him. What was that paper? Why did Nighthawk wish to secure it? I gave up the inquiry in despair.

"Well," I said, "I will not remain longer; I might scare off your friend, and to eaves-drop is out of the question, even if you were willing that I should be present."

"In fact, colonel, I shall probably discuss some very private matters with my friend Swartz, so that--"

"You prefer I should go."

Mr. Nighthawk smiled; he was too polite to say "yes."

"You are not afraid to meet your friend in this lonely place?" I said, rising.

"Not at all, colonel."

"You are armed?"

Mr. Nighthawk opened his coat, and showed me a brace of revolvers.

"I have these; but they are unnecessary, colonel."

"Unnecessary?"

"I have an understanding with Swartz, and he with me."

"What is that?"

"That we shall not employ the carnal weapon; only destroy each other by superior generalship."

"You speak in enigmas, Nighthawk!"

"And yet, my meaning is very simple. If I can have Swartz arrested and hung, or he me, it is all fair. But we have agreed not to fight."

"So, if you caught him to-night, you could have him hung as a spy?"

"Yes, colonel; but nothing would induce me to betray him."

"Ah!"

"I have given him my parol, that he shall have safe conduct!"

I laughed, bade Nighthawk good-bye, and left him smiling as I had found him. In ten minutes I was again on the Brock road, riding on through the darkness, between the impenetrable thickets.

XXVI.

STUART SINGS.

My reflections were by no means gay. The scenes at the lonely house had not been cheerful and mirth-inspiring.

That grinning corpse, with the crust of bread in the bony fingers; that stain of blood on the floor; the grave of Achmed; lastly, the appointment of the mysterious Nighthawk with the Federal spy; all were fantastic and lugubrious.

Who was Nighthawk, and what was his connection with Mohun? Who was Mohun, and what had been his previous history? Who was this youth of unbounded wealth, as Nighthawk had intimated, in whose life personages supposed to be dead, but still alive, had figured?

"Decidedly, Mohun and Nighthawk are two enigmas!" I muttered, "and I give the affair up."

With which words I spurred on, and soon debouched on the Orange plank road, leading toward Mine Run.

As I entered it, I heard hoof-strokes on the resounding boards, and a company of hors.e.m.e.n cantered toward me through the darkness. As they came, I heard a gay voice singing the lines:--

"I wake up in the morning, I wake up in the morning, I wake up in the morning, Before the break o' day!"

There was no mistaking that gay sound. It was Stuart, riding at the head of his staff and couriers.

In a moment he had come up, and promptly halted me.

"Ah! that's you, Surry!" he exclaimed with a laugh, "wandering about here in the Wilderness! What news?"