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The Mystery of the Sea

day before had shown me that whoever used the path near the monument used it in the grey of the dawn. As usual I hid my bicycle and took my way cautiously to the monument. By this time the sun was up and the day was bright; the dew lay heavy, and when I came on any of my threads I could easily distinguish them by the shimmering beads which made each thread look like a miniature rope of diamonds.

Again the strings across the path were broken. My heart beat heavily as I began to follow back towards the monument the track of the broken thread. It led right up to it, on the side away from the castle, and then stopped. The other threads all round the monument were intact. Having learned so much, my first act was to prevent discovery of my own plan. Accordingly I carefully removed all the threads, broken and unbroken. Then I began to make minute investigation of the monument itself. As it was evident that whoever had broken the threads had come straight from it, there was a presumption that there was an opening somewhere. The rock below was unbroken and the stonework was seemingly fixed on the rock itself. By a process of exclusions I came to the belief that possibly the monument itself might be moveable.

Accordingly I began to experiment. I pressed against it, this way and that. I tried to move it by exercising pressure top and bottom in turn; but always without avail. Then I began to try to move it sideways as though it might be on a pivot. At first there was no yielding, no answer of any kind to my effort; but suddenly I thought I perceived a slight movement. I tried again and again, using my strength in the same way; but with no result. Then I tried turning it in the suspected direction, holding both my hands low down on the corners of the boulder; then going gradually up higher I pursued the