That afternoon I went to the house at Whinnyfold. Most of the things which I had ordered had arrived, and when I had had the various boxes and bundles moved inside I felt able to start on my work.
First I rigged up a proper windlass over the hole into the cave; and fixed it so that any one could manipulate it easily and safely from above. It could be also worked from below by aid of an endless chain round the axle. I hammered the edges of the hole somewhat smoother, so that no chance friction might cut the rope; and I fixed candles and lanterns in various places, so that all the light which might be necessary could be had easily. Then I furnished a room with rugs and pillows, and with clothes for Marjory for changing. She would be sure to require such, when our search after the treasure should come off. I had ready some tins of provisions, and I had arranged at the hotel that as I might sometimes stay and work in my own home—I was supposed to be an author—some fresh provisions were to be sent over each morning, and left ready for me with Mrs. Hay at Whinnyfold. By the time my work was through, it was late in the evening, and I went to the hotel to sleep. I had arranged with Marjory to be with her early in the morning. It was hardly daylight when I woke, but I got up at once and took my way towards Crom, for the experience of the 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 same effort; again no response. Still I felt I was on the track and began to make efforts in eccentric ways. All at once, whilst I was pressing with my left hand low down whilst I pulled with my right high up on the other edge, the whole great stone began to move in a slow easy way, as though in perfect poise. I continued the movement and the stone turned lazily over on one side, revealing at my very feet a dark opening of oval form some three feet across its widest part. Somehow I was not altogether surprised; my head kept cool in what was to me a wonderful way. With an impulse which was based on safety, lest the opening of the hole should make discovery of my presence, I reversed the action; and the stone rolled slowly over to its old position. Several times I moved it from its place and then back again, so that I might become accustomed to its use.
For a while I hesitated as to whether I should explore the opening immediately; but soon came to the conclusion that I had better begin at once. So I went back to my bicycle and took the lamp with me. I had matches in my case, and as I had the revolver which I always carried now, I felt equal to any emergency. I think I was finally influenced in my decision to attempt the passage at once by the remembrance of Marjory’s remark that the kidnappers would make no effort until their plans were quite complete. They, more than I, might fear discovery; and on this hope I was strong as I lowered myself down through the narrow opening. I was glad to see that there was no difficulty in moving the stone from the inside; there were two iron handles let into the stone for the purpose.
I cannot say I was at ease in my mind, I was, however, determined to go on; and with a prayer to God for protection, and a loving thought of Marjory, I went on my way.
The passage was doubtless of natural origin, for it was evident that the seams in the rock were much like those on the coast where the strata of different geological formations joined. Art had, however improved the place wonderfully. Where the top had come too low it had been quarried away; the remnants still lay adjacent where the cave broadened out. The floor where the slope was steep was cut into rough steps. Altogether, there were signs of much labour in the making of the passage. As I went down, I kept an eye on the compass whenever I came to a turn, so that I might have a rough idea of the direction in which I was going. In the main the road, with counterbalancing curves and angles, led straight down.
When I had got to what I considered must be half way, allowing for the astounding magnitude which seems to be the characterisation of even a short way under ground; the passage forked, and at a steep angle another passage, lower and less altered than that along which I had come, turned away to the left. Going a few feet up it I could hear the sound of running water.
This was evidently the passage to the reservoir.