Slowly I circled the great shaft, looking for a means of ingress. Part way around I found a tiny radium flash torch, and as I examined it in mild curiosity as to its presence there in this almost inaccessible and unknown spot, I came suddenly upon the insignia of the house of Thurid jewel-inset in its metal case.
I am upon the right trail, I thought, as I slipped the bauble into the pocket-pouch which hung from my harness. Then I continued my search for the entrance, which I knew must be somewhere about; nor had I long to search, for almost immediately thereafter I came upon a small door so cunningly inlaid in the shaft’s base that it might have passed unnoticed by a less keen or careful observer.
There was the door that would lead me within the prison, but where was the means to open it? No button or lock were visible. Again and again I went carefully over every square inch of its surface, but the most that I could find was a tiny pinhole a little above and to the right of the door’s center—a pinhole that seemed only an accident of manufacture or an imperfection of material.
Into this minute aperture I attempted to peer, but whether it was but a fraction of an inch deep or passed completely through the door I could not tell—at least no light showed beyond it. I put my ear to it next and listened, but again my efforts brought negligible results.
During these experiments Woola had been standing at my side gazing intently at the door, and as my glance fell upon him it occurred to me to test the correctness of my hypothesis, that this portal had been the means of ingress to the temple used by Thurid, the black dator, and Matai Shang, Father of Therns.
Turning away abruptly, I called to him to follow me. For a moment he hesitated, and then leaped after me, whining and tugging at my harness to draw me back. I walked on, however, some distance from the door before I let him have his way, that I might see precisely what he would do. Then I permitted him to lead me wherever he would.
Straight back to that baffling portal he dragged me, again taking up his position facing the blank stone, gazing straight at its shining surface. For an hour I worked to solve the mystery of the combination that would open the way before me.
Carefully I recalled every circumstance of my pursuit of Thurid, and my conclusion was identical with my original belief—that Thurid had come this way without other assistance than his own knowledge and passed through the door that barred my progress, unaided from within. But how had he accomplished it?
I recalled the incident of the Chamber of Mystery in the Golden Cliffs that time I had freed Thuvia of Ptarth from the dungeon of the therns, and she had taken a slender, needle-like key from the keyring of her dead jailer to open the door leading back into the Chamber of Mystery where Tars Tarkas fought for his life with the great banths. Such a tiny keyhole as now defied me had opened the way to the intricate lock in that other door.
Hastily I dumped the contents of my pocket-pouch upon the ground before me. Could I but find a slender bit of steel I might yet fashion a key that would give me ingress to the temple prison.