t last, as one of the portals swung open, young Abbot saw what appeared to be four deep-sea diving-suits. Could these suits contain human beings? And if so, who? It seemed incredible, for no diving-suit had ever been devised in which a man could descend to the depth of one mile, and live.

These four figures, whatever they were, came stolidly forward and took charge of the cart. One of the sharks swam up to them and appeared to talk to them with its hands. Then the sharks unhitched the two sea-serpents and led them to the rear, and Abbot saw them no more.

The four divers picked up the chains, and slowly towed the cart forward, their clumsy, ponderous movements contrasting markedly with the swift and sure swishings which had characterized the man-sharks and their snake-like steeds.

Several more pairs of doors were passed, and then there met them four figures in less cumbersome diving-suits, like those ordinarily used by men just below the surface of the sea. One of the deep-sea divers then pressed his face close to the outside of one of the windows of the bathysphere, as though to take a look inside; but the four newcomers waved him away, and hurriedly picked up the chains. Nevertheless, in that brief instant, Abbot had seen within the head-piece of the diver what appeared to be a bearded human face.

Several more pairs of doors were passed. The four deep-sea divers floundered along beside the cart, quite evidently having more and more difficulty of locomotion as each successive doorway was passed, until finally they lay down and were left behind.

At last the procession entered a section of tunnel which was square, instead of circular, and in which there was a wide shelf along one side about three feet above the floor. The four divers then dropped the chains, and one by one took a look at Abbot through his window.

And he at the same time took a most interested look at them.

They had unmistakable human faces!