looking for me—egged on by Mrs. Cameron?"

"There is a reward of $10,000 offered for the arrest of the guilty party," was the unsatisfactory reply, "and the police officers are raking the city to find any one who was in the building last night."

"Did they arrest Jimmie McGraw?" asked Fremont, hoping that the bright little fellow had not been placed in prison.

"Jimmie ran away, just as he said he would, called a surgeon and left the building before he arrived. The police followed him to a room where members of the Wolf Patrol meet occasionally, but he was not there. The boys who were there, night messengers and the like, who had dropped in before going home, said that he had gone South. I met a boy named Frank Shaw, and he said the Black Bears were getting ready to do something for you, though he would not say what it was."

"Good old Frank!" exclaimed Fremont.

"The Black Bears are loyal," Nestor went on, "and so are the Wolves. We may hear from both patrols after we cross the Rio Grande."

"I wish some of them were going with us," said Fremont, with a sigh.

"If I am not mistaken," Nestor said, with a frown, "we'll have plenty of company on the way down. We may not see our traveling companions, but they will be close at hand."

"Do you mean that the police will trail us to Mexico?" asked Fremont.

"I don't know," was the reply. "I give it up. There are others beside the police to reckon with. Well, we'll see what Boy Scouts can do to protect a friend who is in trouble."

CHAPTER V.

THE WOLF IN THE BEAR'S BED.

The two boys traveled for three days and nights, the general direction being south. There were, however, numerous halts and turns in the journey to the Rio Grande. Three times Fremont was left alone at junction towns while Nestor took short trips on cross lines. Once the patrol leader was absent hours after the time set for his return, and the boy was anxious as well as mystified.

Fremont knew that his traveling companion was receiving telegrams in code all the way down, and knew, also, that his movements were in a measure directed by them. Still, one delay seemed to lead to another, as if new conditions were developing. The movements of the boys, too, were carefully guarded, so carefully, indeed, that it seemed to Fremont that Nestor was continually spying upon some one, as well as hiding from those who were spying upon him.

Time and again Fremont asked his friend to explain the mystifying situation, but never succeeded in gaining satisfactory information on the subject of the frequent halts and seemingly useless journeys back and forth. At various times during the journey he secured newspapers containing wild and improbable theories of the crime which had been committed in the Cameron building. Mr. Cameron's death, the dispatches said, was hourly expected, so the unfortunate boy received little encouragement from his reading of the New York news.

Early in the evening of the third day out the boys reached El Paso, on the Texas side of the Rio Grande. They found the city looking like a military encampment. Soldiers wearing the khaki uniforms of Uncle Sam were everywhere, martial music filled the air with its shrill fifings and deep drum-beats, and there was a gleam of polished steel wherever the boys walked.

It was a scene well calculated to stir the imagination and excite the patriotism of the Boy Scouts, and for a time the excitement of it all forced Fremont's troubles from his mind. The boys dined at a restaurant and then Fremont went to a comfortable room which had been engaged in a small hotel while Nestor went out into the city, "to spy out the resources of the land," as he declared.

Fremont, however, knew that his friend was very anxious over something. There appeared to be some new complication which the patrol leader was having a hard time puzzling out. It may well be imagined that his return was awaited with impatience. His face was very grave when at last he entered the room.

"I'm sorry I have no better report to make," Nestor said, throwing himself into a chair, "but the fact is that we've got to lose ourselves in the mountains across the river as soon as we can do so. We can get across to-night, of course, but must hustle after we get across. We can get provisions at San Jose."

"We've got to carry the provisions into the mountains on our backs?" asked Fremont.

"We surely have," was the reply, "and we've got to lay low while we are cooking and eating them. The Sierra del Fierro mountains, where we are going, are lined with insurrectos, and they are not in good humor just now."

"I'm game for anything, so long as we can get out of the beaten way," replied Fremont. "I've felt all the way down that we were being followed. Anyway," he continued, more cheerfully, "I shall enjoy the sight of a mountain campfire again. We don't have to take any matches with us. I can build a fire, Indian-fashion, with dry sticks and a cord. My Boy Scout experiences will be of service now, I take it."

"And you must fix up a little disguise to get over the river in," continued Nestor. "The New York police are in communication with the officers here, and the latter are out for the $10,000 reward. As you suspected, we have been shadowed from New York. More than once I threw the shadows off the track, but they landed again. There are most unusual conditions around us, and we must be very discreet. After we get across the Rio Grande the danger will decrease."

"It makes me feel happy again," Fremont said, after putting on a new, cheap suit and tinting his face, "this idea of meeting a different sort of danger. I can't stand this lurking peril—this obsession that some one may spring out upon me from some dark corner at any minute. Get me out by a mountain camp-fire, old fellow, and I'll be game for anything."

There was a short silence, and then the boy went on.

"I don't understand exactly why you are heading for Mexico, but one country is as good as another just now. The police over there are said to be in close touch with those here, and to be brutal in their handling of prisoners. However, let us make up our minds that we will have nothing to do with the police."

"We are going to Mexico for three reasons," Nestor said, in a moment. "I can't tell you all about the three now, but one is to get you out of the way until the real criminal is discovered. The other two will show in time, and are likely to bring out a great deal of excitement."

"I have been wondering all the way down here," Fremont said, "why you copied one of the papers in the Tolford estate packet. I know now. There is in that sheaf of papers a description of a lost Mexican mine—a very valuable mine which has been lost for any number of years. I remember of hearing Mr. Cameron discuss the matter with one of the heirs. The lost mine seems to be the most valuable item in the estate schedule," the boy went on. "At any rate, there has been a lot of quarreling over it. That paper contains the only description in existence, and all the heirs want it."

"So you think I'm going after the lost mine?" laughed Nestor.

"If you are not, why did you copy the description?"

"How do you know that I copied the description?"

"You copied something."

"Yes; I copied the description of the lost mine. I thought it might be of use to us, and it may prove of the greatest importance."

"Then you think the man who invaded the office and struck Mr. Cameron down is interested in the lost mine?" exclaimed Fremont. "You think he committed the crime to get the description? That he copied it, and left the original paper there to throw off suspicion? That the man we are in quest of will go directly to the lost mine? Is that why you are going to Mexico? Is that why you said, from the start, that the clue pointed across the Rio Grande?"

"Don't ask so many questions," laughed Nestor. "There