"Why, sir, how does it happen that, right on top of such extra-fine
ore we run upon blank rock at the very next blasting."

"That sometimes happens in _El Sombrero_," Don Luis replied, smoothly,

"How often has it happened?" asked Tom, looking up from the table
and glancing keenly at Don Luis.

Dr. Tisco, though he appeared to be almost asleep, stirred uneasily.

"How often has it happened?" repeated Don Luis. "Oh, perhaps
a dozen times in a few months, taking all the tunnels together."

"How long have these streaks of blank rock been?" insisted Tom
Reade, while Harry wondered at what his chum was driving.

"How long?" echoed Montez, with a shrug of his shoulders. "Oh,
how should I know? Personally I am not interested in such things."

"But have you gone as much as a whole week drilling and blasting
through blank rock?" Tom pressed.

"A week? No; not for two days. Of that I am certain. But why
do you ask all this, Senor Tomaso?"

"In order that I may better understand the nature of the mine,"
Reade responded. "I want to know what the chances are, as based
on the record of the mine to date. Of course, Don Luis, you know
what it means, often, when pay ore fails to come out of a streak,