"Is all quiet to-night, Señor?" asked Jack, after the first compliments had passed.
"Yes; nothing has happened since the French blew up a house by the Santa Engracia convent just before dark. But one thing puzzles me, Señor. Do you know this part of the city?"
"I was here once before, but that was six years ago, and I was too much a child then to remember it well now."
"But you will know that beyond the wall here, which has been greatly strengthened and thickened, the ground slopes steeply down to the River Huerba. You can see it; the water shines in the moonlight. On the other side of the ravine, at the top, are the French trenches."
"I am coming to it. Every night for ten days past I have been at this spot at this hour, and every night I have either seen or heard a French sentry exactly opposite. To-night, however, there is a difference. At dusk we saw the Frenchman tramping up and down behind the trench, just out of range of your good English muskets, Señor; we heard the guard changed; but a few minutes ago, when I looked, I found that the sentry had disappeared. Perhaps my eyes are at fault. Will you look, Señor?"
Jack looked across the ravine. A pale half-moon was shining, as yet somewhat low in the sky, and the ravine and river-bed were gloomed by black shadows. The line of the entrenchments showed rugged against the background, in which watch-fires here and there marked the night bivouac of the French. From the far distance came faint and fitful noises; the gurgling wash of the river against its embankments made the only sound in the vicinity. Jack ran his eyes along the edge of the entrenchment for a hundred yards in each direction. Certainly no sentinel was in sight.
"Perhaps he is resting," he remarked. "There is no need for him to tramp up and down in sight all the time."
"True, Señor, but why to-night? Why on this night should we miss what we have seen without exception for many nights past?"
"It is certainly strange. I shouldn't think it implied any particular danger of an attack; should you?"
At this moment Pepito touched him on the arm.
He pointed across the river towards a spot in deep shadow half-way down the opposite slope. Jack looked in that direction, but failed to perceive any moving object.