“Pardon me, Don Luis,” murmured Dr. Tisco, “but to me they do not look like such fools.  They will suspect; they will even know.”

“It matters little what they suspect, if they hold their tongues,” replied the mine owner.

“You will have to appeal to their love of money, then,” suggested the secretary.  “You will have to pay them extremely well.  Even then they may balk and refuse.”

“Refuse?” repeated Don Luis opening his eyes wide.  “Carlos, you do not seem to understand how hopeless it would be for them to refuse.  I am master here.  None knows better than you that I hold life and death in my hand in these mountains.  Do not all men hereabouts obey my orders?  Will el gobernador ask any awkward questions if two Gringos should stroll through these mountains and never be heard from again?  Who can escape the net that I am able to spread in these mountains?  The Gringos refuse me—­betray me?  Are they such fools as to refuse me when they find that I hold their lives in the palm of my hand?”

“They may even refuse your bait with death as the alternative,” persisted the secretary.  “Don Luis, you know that there are such foolish men among the Gringos.”

“Then let them refuse me,” proposed Don Luis, jestingly, though his white teeth shone in a savage smile.  “If they are difficult to manage—­these two young Gringos—­then they will quickly disappear, and other Gringos shall come until I find those that will serve me and be grateful for their rewards.”

“I wish you good fortune with your great schemes, Don Luis,” sighed young Dr. Tisco.

“Carlos, you have not eaten for hours.  You are so famished that the whole world is colored blue before your eyes.  Come, it is close to the hour for the meal.  You shall meet and talk with my Gringos.  You will then be able to judge whether I shall be able to tame them.”

CHAPTER II

THE WOLF WHO SHOWED HIS TEETH

A rare host at table was Don Luis Montez.  He possessed the manner, even if not the soul, of a great nobleman.

His daughter, Francesca, reputed to be a beauty, did not appear at table.  So far the young engineers had not met her.  They would be presented, however, within a day or two, after the Mexican custom, for Tom Reade and Harry Hazelton were to be guests in the white palace during their residence in this part of Mexico.

Dr. Tisco, too, tried to be most entertaining, and succeeded.

“You are the surgeon at the mine?” Harry ventured.

“A medico?” suggested Dr. Tisco, with a bow of humility.  “Ah, no, senor, I have not that honor.  I am a doctor of philosophy, not of medicine.”

“Then you may be a scientific expert,” Harry hazarded.  “You are the expert here at the mine?”

“Not so,” broke in Don Luis, gently.  “It is true that Carlos has some knowledge of chemistry, but he is not a mining expert.  He is my secretary, my man of affairs.”