All at once he bethought himself of the cave whence she had emerged. It was close at hand--a natural grotto, arched and apparently lofty. He resolved to explore it. Glancing at his watch he saw it was not yet one o'clock in the morning, yet the voice of the cuckoo called shrilly from the neighboring hills, and a circling group of swallows flitted around him, their lovely wings glistening like jewels in the warm light of the ever-wakeful sun. Going to the entrance of the cave, he looked in. It was formed of rough rock, hewn out by the silent work of the water, and its floor was strewn thick with loose pebbles and polished stones. Entering it, he was able to walk upright for some few paces, then suddenly it seemed to shrink in size and to become darker. The light from the opening gradually narrowed into a slender stream too small for him to see clearly where he was going, thereupon he struck a fusee. At first he could observe no sign of human habitation, not even a rope, or chain, or hook, to intimate that it was a customary shelter for a boat. The fusee went out quickly, and he lit another. Looking more carefully and closely about him, he perceived on a projecting shelf of rock, a small antique lamp, Etruscan in shape, made of iron and wrought with curious letters. There was oil in it, and a half-burnt wick; it had evidently been recently used. He availed himself at once of this useful adjunct to his explorations, and lighting it, was able by the clear and steady flame it emitted, to see everything very distinctly. Right before him was an uneven flight of steps leading down to a closed door.
He paused and listened attentively. There was no sound but the slow lapping of the water near the entrance; within, the thickness of the cavern walls shut out the gay carolling of the birds, and all the cheerful noises of awakening nature. Silence, chillness, and partial obscurity are depressing influences, and the warm blood flowing through his veins, ran a trifle more slowly and coldly as he felt the sort of uncomfortable eerie sensation which is experienced by the jolliest and most careless traveller, when he first goes down to the catacombs in Rome. A sort of damp, earthy shudder creeps through the system, and a dreary feeling of general hopelessness benumbs the faculties; a morbid state of body and mind which is only to be remedied by a speedy return to the warm sunlight, and a draught of generous wine.
Sir Philip, however, held the antique lamp aloft, and descended the clumsy steps cautiously, counting twenty steps in all, at the bottom of which he found himself face to face with the closed door. It was made of hard wood, so hard as to be almost like iron. It was black with age, and covered with quaint carvings and inscriptions; but in the middle, standing out in bold relief among the numberless Runic figures and devices, was written in large well-cut letters the word-THELMA "By Jove!" he exclaimed, "I have it! The girl's name, of course! This is some private retreat of hers, I suppose,--a kind of boudoir like my Lady Winsleigh's, only with rather a difference."