“Suppose we catch sight of some one stealing up?” asked one of the cattlemen.

“Challenge him, and if he does not give a satisfactory response, fire.”

“What will be a satisfactory response?”

“The voice of Fred Whitney, and I may say of Duke Vesey, or the announcement that the individual is the bearer of a message for us.  In the latter case, of course, he will approach from the front.  When you shoot, too, boys, you mustn’t throw away any shots, for this isn’t going to be child’s play.”

“We understand that,” was the significant response of a couple of the stockmen.

It was now growing so late that Sterry placed himself near the rear door to watch for the expected signal from Vesey, feeling, as the minutes passed, a nervousness greater than at any time before.

Since no light burned in the house, the only means of determining the hour was by striking a match and holding it in front of a watch.  Hope became high when 10 o’clock was at hand.

Sterry half expected, in case everything promised well, that Vesey would manage to give something in the nature of a preliminary signal, but the closest scrutiny showed nothing of the kind.

Capt.  Asbury, who maintained his place near one of the front windows, close to the door, suddenly called: 

“Come here a moment, Sterry.”

The young man stepped hastily across the room.

“You have everything clear in your mind?” was the question which struck the young man as slightly inopportune.

“Yes; as clear as I can have; why do you ask?”

“I wanted to be certain, for your task is a delicate one; we will hold the door ajar a little while after you go, so that if anything happens, such as their recognizing you, you will be able to dash back.  You know it won’t do for you to be identified.”

“I understand,” replied Sterry, who felt that he ought to be at his post.

He hastily stepped back, and as he did so was surprised to find the door drawn open several inches.

“What does that mean?” he asked of the several gathered around in the darkness, whose faces he could not see.

“Why,” replied Hawkridge, “what does it mean, indeed?  I thought you passed out just now.”

“You see I did not.  Why do you make such a remark?”

“Some one went out,” was the amazing declaration.

CHAPTER XXX.

THE MISSING ONE.

Monteith Sterry was astounded by the declaration of Dick Hawkridge that some one had passed through the rear door while he was talking with Capt.  Asbury.

“Who was it?” demanded he.

“I told you we thought it was you,” replied his friend.

“But you know it wasn’t,” he replied, impatiently.

“Then I have no idea who it was.”

“Some one has taken advantage of the moment I spent with the captain—­I wonder if he had anything to do with it,” he added, growing unjustly suspicious in his resentment.