"It _is_ a fine mine, isn't it, Senor Tomaso?" demanded Don Luis, enthusiastically.

"From all indications it ought to be," Reade answered. "Yet it's a new formation of rock to me--this sandwich formation as I might call it, with the alternate layers of rich ore and blank stuff."

"I have been drawing up a report on the mine," murmured Montez, opening a drawer in his desk. "This report describes the operations and the profits so far. Glance through it with me."

The report had been written in English, by either Dr. Tisco or his employer.

Tom and Harry listened carefully to the reading.

"But why do you put so much enthusiasm into the report, Don Luis, when the mine is not for sale and is not to be run as a stock company property?"

"Of course, _El Sombrero_ is my sole property, and of course I shall keep it so," smiled the Mexican. "But I like, even in a report to myself, for my own use, to have the report set forth all the truths concerning the mine."

"That is reasonable," Tom agreed.

"Now, Senor Tomaso, as you have seen, this report is couched in my own English. I would be glad if you would write this out for me, putting it into better English."

"It would seem like presumption in me to think that I could put it into better English," Reade protested.

"Nevertheless, to please me, will you put this report into your own English?" requested Don Luis.

"With all the pleasure in the world," Tom a.s.sented.

"Here are writing materials, then."

"But I see that you have a typewriting machine over in the corner,"

suggested the young chief engineer. "I can write the report much better and more rapidly on the machine."

"Ah!" breathed the Mexican, looking highly pleased. "If you will but do that! We will go outside so as not to disturb you."

The report, being a long one and containing several tables of figures, Reade was occupied nearly three hours. During this time Don Luis conducted Harry over the estate, pointing out many things of interest. At last Tom, with a slight backache from bending so long over the machine, leaned back and carefully read what he had written.

"Do you wish anything, _caballero_?" inquired Nicolas, appearing as though from hiding.

"You might be good enough to tell Don Luis that I have finished, and that I await his pleasure."

Nicolas disappeared. Five minutes later Montez, his secretary and Hazelton came in. Tom read through his typewritten draft of the report.

"Excellent! gr-r-r-rand! glorious!" breathed Don Luis. "Ah, you are a master of English, Senor Tomaso. Myself, I understand Spanish better. And now one stroke of the pen for each of you,"

added the _hidalgo_, crossing the room to his desk. "As my new engineers you shall both sign this report, and I shall have much pleasure from reading this, many times, when I am an old man."

Don Luis dipped a pen in ink, then held it up. Harry was about to take the pen when Tom Reade drawled:

"It wouldn't be quite right for us to sign this report, Don Luis."

"Why not?" queried the Mexican, wheeling like a flash.

"Just for the simple reason," Reade answered, "that to sign the report would be to state all the facts contained in the report as being of our personal observation. We haven't seen enough of the mine, as yet, for it to be right for us to sign the report.

An engineer's signature to a report is his statement--ON HONOR--that he personally knows such report to be true. So I am very certain you will understand that it would be a breach of honor for us to sign this doc.u.ment."

"Ah! He is clever--and now the real trouble must begin!" Dr.

Tisco told himself. "These engineers are not easily duped, but in Don Luis's hands they will destroy themselves!"

CHAPTER VI

WATCHING THE MIDNIGHT LIGHTS

Don Luis Montez laid down the pen. Outwardly he was as amiable as ever; certainly he was all smiles.

"A thousand pardons, _caballeros_!" he murmured. "Of course, you are quite right. It had not occurred to me in that light before.

True, the report was intended only for my own pleasure in later years, but that does not alter the nice point of honor."

Tom Reade was deceived by Don Luis's manner. He did not suspect that, at this very instant, the Mexican was consumed with demoniacal rage.

"I shall not be patient another time," muttered Don Luis, between his teeth and under his breath. Yet aloud he said:

"We have had too much of business to-day. We are tiring ourselves.

Until dinner time let us go outside and be gentlemen. Business for to-morrow or next week. And my dear daughter. Brute! I have been forgetting her."

Senorita Francesca, a darkly beautiful girl of eighteen, shy and retiring from the convent schooling that had ended but lately, soon came downstairs at her father's summons. Dr. Tis...o...b..wed low before the charming girl. Tom and Harry were presented, and tried to make themselves agreeable to the young Mexican girl.

Senorita Francesca's shyness, however, made this somewhat difficult, so the young engineers felt inwardly grateful when Dr. Tisco strolled down the porch with her.

Dinner proved to be a somewhat formal affair. Yet, as soon as the meal was finished Senorita Francesca was escorted from the dining room by her father and returned to her room.

"What did you think of the young lady, Tom?" Harry asked his chum when he could do so privately.

"A fine-looking girl," Reade answered briefly. "But I fear she would be highly offended if she knew that, all through dinner, my every thought was on the mine and the problems that we shall find there."

"I want to talk with you about that mine, and about some impressions that I have formed here," murmured Hazelton.

"Then another time, my dear fellow, for here comes Don Luis, and I see Dr. Tisco returning from the garden."

That forestalled conversation for the time being. When the young engineers, still relentlessly attended by Nicolas, sought their own rooms Hazelton was so drowsy that he undressed hurriedly and dropped into bed.

Later in the night Harry sat up suddenly in the dark. Some one was moving in the parlor that separated the two bedrooms. An instant after awakening Harry slipped off the bed, then stole toward the next room.

In the darkness he made out a moving figure. Like a panther Harry sprang, landing on the all but invisible figure.

"Now, I've got you!" Hazelton hissed, wrapping his arms around the prowler.

"And small credit to you," drawled Tom's dry voice. "Hist!"

"What's up?" demanded Hazelton, dropping his voice to a whisper.

"You and I are."