There was a crashing, tinkling sound as the point of the arm struck the furry body of the rat-man. Then the arm's point sprayed into a web of shining filaments that laced the rodent's body inexorably in their web. The arm immediately contracted, jerking the victim irresistibly toward the waiting crystal. A second later the rat-man was pinned against the faceted crystalline side just under the opalescent nucleus. The moment the furry body made contact with the crystal's side a terrifying phenomenon occurred. Crystals grew and spread all over its form with the lightning growth of water-glass. Faster and faster clustered the crystalline shroud, until the furry body was lanced through and through--and all the time the air was filled with eldritch music as of a thousand sheets of thinnest glass crashing, tinkling and shattering. The crystal growths over the imprisoned body rounded their contours and merged together until they were in the form of a great crystalline egg. The outlines of the rodent's body blurred and vanished, melting swiftly until only a diamond-encrusted skeleton was left. The color of the great Devil Crystal began to gleam pink as the victim's flesh and blood were absorbed. The egg-like excrescence under the nucleus turned in hue to pale translucent amber in whose depths the diamond skeleton gleamed with weird brilliance. Then there came a sudden twang, as of a violently plucked string on a bass viol, and the amber egg dropped from the faceted side. The Crystal's feast was over. One of the most terrifying aspects of the whole thing had been its incredible speed. The entire tragedy had occurred in but little over two minutes from the time the lance-arm had first struck the rat-man. In the meantime the body of the second rodent had been drawn in and devoured by another of the carnivorous crystalline monsters. There came a second twang now, as its skeleton in its amber shroud was discarded. * * * * * Powell's brain reeled as he saw the other crystals move sluggishly nearer the foot of the rocky projection in anticipation of the next victims. The remaining two captive rat-men came next. They were swiftly drugged, unbound, and started on their dazed march. They trudged woodenly out the rocky projection to its end, then on and over; and again the grim tragedy of the Devil Crystal's feast was repeated, to the accompaniment of that eerily beautiful crashing, tinkling song. The four Devil Crystals that had completed their gruesome feast moved sluggishly away, leaving the space clear for the two crystals that remained unfed. The score of guards closed in upon Joan and Powell. With the crystalline doom at last staring them squarely in the face, Powell went berserk in a final desperate effort to gain even a moment's respite. He lashed out in a writhing, kicking flurry that almost cleared the space around them.