The melody produced--if it could be called a melody--was of an extraordinary character. Its effect, its charm--for it had unmistakable charm--was quite impossible to define. In some respects it resembled the monotonous chantings peculiar to most primitive races, occasionally, as was customary with the latter, rising and falling, whole octaves at a time, in a wailing key. In the main, it carried a sort of theme, emotional and inspiring, that was far too complex to be attributed to the uncultivated musical taste common to savagery. There was an exultant swing to the measure, a lilting cadence that betrayed a fine esthetic sense, a rich imagination coupled with the simplicity and freedom that has not felt the pressure, except very remotely, of our western civilization. Such music was good to listen to--and under ordinary circumstances the explorers would have been content to listen and nothing more. But curiosity, and some remnant of fear the lulling influence of the music had not dissipated, kept them on the alert. Their fate depended, they felt, on these musicians. They must find out who they were before it was too late to retreat. And then--presently--through the clustering green and white stems of the stalactites, they caught sight of them. They were over twenty in number, moving, as nearly as the unevenness of the ground would permit, in time to the choral march they were playing. At sight of them Mrs. Quayle didn't know whether to be pleased or terrified. For the music was such an enchanting, soothing sort of thing, and the players so mild, benignant of aspect, anything like fear seemed out of place. But, on the other hand, the strange instruments they carried, their outlandish dress, the whole effect of them, in a way, was distinctly unearthly, supernatural--and Mrs. Quayle drew the line at the supernatural. So, she ended by being simply amazed beyond measure--and her companions shared her feelings in lessening degree. Miranda and Herran, dumbfounded by the apparition, forgot to handle their revolvers in the warlike fashion they had intended with the first approach of a foe; Andrew gaped in an open-mouthed sort of dream, during which his pocket-knife came imminently near doing fatal execution upon himself, while Una and Leighton, forgetting their anxiety, were lost in admiration of the delicious music and of the spectacle before them. One and all of this singular band of cavemen were clothed after the fashion described by Andrew. Each wore a loose white mantle, or toga, that draped the figure in voluminous folds, adding to the grace and freedom of movement with which they kept time to the music. Their feet were shod with sandals, their heads encircled with bands of white cloth from the flying ends of which hung ornaments of gold and emerald. The musical instruments upon which they played were long, slender tubes, curving upward at the extremity, of a metal that glittered and sparkled like the purest gold.