others of his party, Stacy this time well up toward the front of the line. For reasons of his own he did not care to drag behind. If there was to be any shooting he wanted to be as far away from it as possible.

The trip was made at a fast gallop and without incident, the party reaching the hollow without having drawn a shot from the enemy.

"It is my opinion," declared the professor, "that, whoever our enemy may be, he has discovered that he has made a mistake."

Tad shook his head.

"I don't think we would be safe in taking that for granted. He did not see us, but he will be on hand before long. I'm going back there before he does see us. If he starts any more shooting you all lie low."

"Where are you going?" demanded the professor.

"On a scouting trip."

"I cannot consent to any such foolhardy business," answered Professor
Zepplin sternly.

"It is not foolhardy. We've got to clear up this mystery. Don't you see, we shan't dare go any farther—-we simply cannot go into the mountains knowing there is some one there waiting to riddle us the first time he gets a clear sight at us?"

"But what do you propose to do?"

"I don't know, beyond finding out what is up."

"Yes, let him go," urged Stacy. "He's looking for trouble. I'm the only one who has had any experience thus far. It's time some one else made a mark of himself."

"I was thinking of taking you with me," laughed Tad.

"No, you don't! Not if I see you coming," objected Stacy.

"Yes, take him along," urged Ned.

"No, I think I'll take you, the Professor being willing," answered Tad nodding at Rector.

Ned stopped smiling, gazing at Tad to see whether the latter were in earnest. Tad was.

"All right, I'm willing, Tad."

"How about it, Professor?"

"Provided you do not go into the mountains I will agree to your plan.
But I cannot consent to your taking further desperate chances."

"I hope you will not hold me to that, Professor."

"To what?" demanded Professor Zepplin shortly.

"To not going beyond the edge of the mountains."

"Plainly, what is it you are planning to do, Tad?"

"I want to find out who it is that is shooting at us and why. That is all, sir."

"You don't suppose it possibly could be the Germans attacking us, do you?" questioned Walter apprehensively.

The professor shook his head.

"If you will stop to think you will see how necessary it is for some one to do something," urged Tad Butler.

"Yes; don't let me do it all," urged Stacy. "I think I have done my share already. It is high time some one else got a move on. First thing we know we shan't know anything. We'll be dead ones, and—-"

"Very good. Go on. There will be no peace here unless you have your way. See to it that you are back here in an hour. If not we shall go after you. Do you understand?"

"Yes, sir, I will try to get back on time. If something should occur to keep us longer than that please don't worry. You know we might not be able to get away. If we get into trouble I will signal by firing three shots into the air. Are you ready, Ned?"

"Yes. Do we take our arms?"

"Better leave the rifles here. We don't want to be bothered with them.
We'll take our revolvers. That will be sufficient."

"Now, Tad, be prudent," begged the professor. "I know you have a level head or I should not permit you to get out of my sight under the circumstances."

"We will be prudent, sir. Come on, Ned; we mustn't waste a moment now.
If we are seen to leave the camp we'll fail."

For answer Ned swung himself into his saddle, after first having taken the rifle from the saddle boot and fastened it to one of the packs.

"Don't pitch the tent yet. We must be in marching order," directed Butler, after leaping into his saddle. "And don't worry about us, for we'll be all right."

Nodding to Ned Tad started off at a fast gallop. But despite Tad's cheerfulness he realized that he had taken upon himself a serious piece of work, one that might be the death of both. Still, he was nothing daunted. He was determined to go to the bottom of the mystery, whatever the cost might be to himself.

Tad knew also that he could depend upon Ned Rector, for Ned was brave and resourceful, a boy who would keep his head in an emergency.

They made the trip to the mountains without incident. There Tad pulled up for a conference.

"Now tell me what your plan is?" said Ned.

"First we will ride on a little further along the base here. I see a place where I think we can hide our ponies. I don't want to go back to the point where we first started to make camp. That is the place where our enemy will be looking for us first. But when he gets there we'll be somewhere in the vicinity."

Ned wheeled his pony without further comment and followed Tad at a slow trot along the base of the foothills. The boys were engaged on a more desperate mission than they knew.

CHAPTER III

IN A BAD MAN'S POWER

Having secreted their ponies in a dense growth of scrub oak, Tad laid out his plan as follows:

"You, Ned, will go straight in from here until you've got about a quarter of a mile directly inland. When you have done so turn due west. I don't think you can lose your way for you can see out every little while and thus get your bearings."

"Where are you going?"

"Back to the point where we first decided to make camp. I shall have easier going than you will, but I shall be in more risk."

"What's the rest?" asked Ned with a short laugh.

"It is my idea to close in on the right fork of the stream there in the foothills. I'll come up from the west and you from the east. In that way we shall close in, you see, covering roughly the greater part of the territory."

"Then you think we shall find our man there?"

"I am sure he will get there eventually, provided he has not seen our movements out there. He will go to the stream and from there he will quickly locate our camp. Understand?"

"As far as it goes, yes. But what are we going to do if we find him?"

"Watch him. Find out what he is up to, then from that on be guided by circumstances. But whatever you do, Ned, don't use your revolver unless it be to save your own life."

"No, I'm not aching to shoot any one. Do you know, Tad, I'm thinking you and I are biting off a bigger mouthful than we will know how to chew?"

"We will manage it somehow."

"What do you think this fellow is trying to do?"

"It looked very much as if he were trying to kill us," smiled Tad.

"It did. But what for?"

"I have an idea the professor was right when he said the fellow mistook us for some other party."

"And he's likely to do it again, if that's the case."

"He may have already discovered his mistake, Ned. You observe he hasn't fired a shot since?"

Rector nodded thoughtfully.

"Well, we must be on the move. We don't want to be caught out here