Not far from his left elbow, in the concave of the outer wall, was a slit for the admission of light, and he perceived at once that through this slit alone lay his chance of communicating with the outer world.

At first it seemed as if it were to be done by shouting, but when he learnt what little effect was produced by his voice in the midst of such a mass of masonry, his heart failed him for a moment.

Yet, as either Paula or Miss De Stancy would probably guess his visit to the top of the tower, there was no cause for terror, if some for alarm.
He put his handkerchief through the window-slit, so that it fluttered outside, and, fixing it in its place by a large stone drawn from the loose ones around him, awaited succour as best he could.

To begin this course of procedure was easy, but to abide in patience till it should produce fruit was an irksome task.

As nearly as he could guess--for his watch had been stopped by the fall--it was now about four o'clock, and it would be scarcely possible for evening to approach without some eye or other noticing the white signal.