“I promised Mr. Frank I would do it until he and Mr. Henry return,” was her answer.

“Promised Frank?  Where has he gone?”

“Gone to find his brother.”

“And you knew what you are telling me when we were exchanging oxen this morning?”

“Yes, sir.”

“Why did you not tell me?”

“Mr. Frank said I must not before we arrived here.”

“Have you no idea of the fearful danger in which he has placed himself?”

“I know he has gone to find Henry, and that he said he should find him,” and the pretty girl betrayed her lack of confidence in the boy’s project by sitting down in the grass and bursting into tears.

“When did Corporal Frank start?” I asked.

“Last night.  He gave Sancho about a dozen pounds of hard bread, filled his canteen with water which Aunt Martha had filtered through sand, and asked me to attend to the odometer, and rode off in the darkness.  Don’t you really believe the boys will return, sir?”

“God grant they may,” I answered; “but it is very doubtful.”

Here was fresh trouble—­trouble the whole command shared, but which rested heaviest upon Captain Bayard and myself.  We were answerable to Colonel Burton for the manner in which we executed his trust.

“Ride down the valley,” said the captain to me after I had concluded my account of what Brenda had said, “and look for Lieutenant Hubbell’s camp.  It cannot be far from here.  Tell him to send me three days’ grain for forty animals.  While you are gone I will select a camp farther down stream, and within easy communication with him, park the train, and establish order.  We will remain here until we know what has become of the boys.”

I found the New Mexican cavalry camp three miles down the river, and obtained the desired forage.  When I returned our new camp was established, fires burning, and cooking well under way.

Captain Bayard informed me that the detachment of Mexican cavalry which had accompanied us thus far would leave at this point and not rejoin us.  “I have ordered Baldwin to grain his horses and be ready to start in search of our boys at daybreak,” continued the captain.  “You will accompany him.  We shall be in no danger, with Hubbell so near.  You can take thirty pounds of grain on your saddles, and you will find plenty of water on the Carizo where it breaks from the hills.”

“How many days are we to stay out?”

“You are to take five days’ rations.  If the boys are not found in that time I fear they will never be found.”

I went to bed early, and soon fell into a fitful slumber, which lasted until an hour before midnight.  I arose, dressed, and sat down by the smouldering camp-fire, a prey to unpleasant reflections.

Suddenly the sound of a cantering horse approaching from the north fell upon my ears.  What could it mean?  I listened intently.  The horse slowed down to a walk.  He entered the camp.  The voice of Private Tom Clary, who was posted as sentinel No. 1, challenged:  “Halt!—­who comes there?”