business that belongs to an hidalgo like Don Luis?"

"It is queer that--"

"Silence!" hissed Gato. "Do not meddle with the secrets of Don
Luis Montez, or you will be sorry for it."

Gato's explanation about the mule-train had quieted the fears
of the bandits as to the approach of troops. In some mountainous
parts of Mexico the government's troops are nearly always on the
trail of bandits and the petty warfare is a brisk one.

"Go to sleep, my friends. There will be nothing to do until day
comes."

"Then, good Gato, take us somewhere off this road," pleaded one
of the men. "It is too public here to be to our liking."

"You may go to a quieter place," nodded Gato. "You know where--the
place I showed you this afternoon. As for me, after the mule-train
has left the mine, I must go there. I will join you before daybreak."

"We'll go now, then," muttered one of the men, rising.

They were coming up the road in the direction of the young engineers.
There was no time to retreat. Tom glanced swiftly around. Then
he made a sign to Harry. Both young engineers flattened themselves
out behind a pile of stones at the roadside. Their biding-place
was far from being a safe one. But four drowsy bandits plodded
by without espying the eavesdroppers. As for Nicolas, he had