He could scarcely see the face even of the priest who conducted them, but from the sounds he gathered that all their party were being guided in a similar fashion.

Once or twice also he heard the voice of a Settlement man speaking in accents of fear or complaint, but such demonstrations were followed quickly by the sound of a heavy blow, dealt, no doubt, by the priest or soldier in charge of that individual.

Evidently it was expected that all should be silent.
Presently Leonard became aware that they had left the open space across which they were walking, for the air grew close and their footsteps rang hollow on the rocky floor.
"I believe that we are in a tunnel," whispered Francisco.
"Silence, dog," hissed a priest in his ear.

"Silence, this place is holy." They did not understand the meaning of the words at the moment, but the tone in which they were spoken made their purport sufficiently clear.
Leonard took the hint, and at the same time clutched his rifle more tightly.

He began to be afraid for their safety.