They had turned the sharp corner, and advanced a few feet beyond when the man with the lantern stopped suddenly, and held it up to permit the light to stream full on the exposed wall to the right.  Another of these odd slits in the rock was visible here, and the girl was able to perceive more clearly its nature—­beyond question it was an artificial opening, leading into a space on the farther side of the wall.  Cateras pushed past her, his body interfering with her view, and bent down, fumbling along the rock surface.

“Hold the light closer,” he demanded.  “Aye, that’s it.  ’Tis some trick to find the thing——­ Ah! now I have it.”

It seemed like a bit of wood, so resembling the colour of the rock as to be practically imperceptible to the eye in that dim light—­a bit of wood which slid back to reveal a heavy iron bolt, shot firmly into the stone.  This the Mexican forced back, and an opening yawned in the side wall, the rays of the lantern revealing the interior of a black cave.  Cateras stepped within.

“Bring the woman,” he commanded shortly, “and you, Merodez, see first to the light.”

Silva thrust her forward, his grip no light one, while the other struck a match and applied it to the wick of a lamp occupying a bracket beside the doorway.  As this caught the full interior was revealed beneath the sickly glow, a cell-like place, although of a fair size, unfurnished except for a rude bench, and one three-legged stool, the floor of stone, and the sides and roof apparently of the same solid structure.  It was gloomy, bare, horrible in its dreariness—­a veritable grave.  The girl covered her face with her hands, appalled at the sight, unnerved at the thought of being left alone in such a place.  Cateras saw the movement, and laughed, gazing about carelessly.

“Some boudoir, senorita,” he said meaningly.  “Well, we will see what can be done for you later.  Perhaps a few hours in such a hole may work a miracle.  When I come again you will be glad to see even me.  That’s all, lads; there’s plenty of oil, and you can bring along some blankets with the evening meal.”

He stopped, standing alone in the narrow opening, the light of the lantern without bringing his face into bold relief.  The girl had sunk helplessly onto the bench, her head bowed within her hands.  The Mexican eyed her frowningly.

“Quite tamed already,” he said sarcastically.  “Bah!  I have done it to worse than you.  Look up at me.”

She lifted her eyes slowly, her lips pressed tightly together.  She was conscious of depression, of fear, yet as her glance encountered his, a sudden spirit of defiance caused her to stand erect.

“There are some women with whom you are not acquainted, Senor Cateras,” she said quietly, desperation rendering her voice firm.  “And possibly I may prove one of them.  I am your prisoner it seems, yet I advise you not to go too far, or I may prove to be a dangerous one.  In the first place it might be well for you to remember that, helpless as I seem at present, I have friends—­whatever befalls me will be known.”