It was dark out there on the deck. The two figures sat some distance from me as I crouched in the turret doorway. But I could see their outlines fairly clearly--Arturo sitting close to her, sometimes whispering. She stood up. She evidently saw something. My heart began pounding. Whatever it was, it was hidden from my position. Arturo was on his feet beside her. She gestured--I could see her slim white arm gesturing. I saw him raise the flash light, and send its narrow, penetrating yellow beam steadily out over the water. That device he had cut in the yellow face of it--something, some one out there must be seeing that--and recognizing it, as Nereid? I thought so. There was a space, while Arturo held the light steadily level. Then Nereid said something to him. He snapped off the light. They stood waiting. A minute? Ten minutes? I do not know. I heard nothing; saw nothing save those two motionless, tense figures standing there by the Dolphin’s low rail. Boy and girl, so slim, so frail, so youthful, both of them. They stood, so close together that her long wild tresses seemed almost enfolding him. I recall that I was about to go below and tell Dr. Plantet and Polly of this signal I had seen. A movement of Nereid stiffened me. She drew apart from Arturo. The Dolphin’s rail was lower than her waist. She seemed poised; her arms went up; she went in a graceful arc, over and head downward into the sea. [Illustration: _Nereid went in a graceful arc into the sea._] I was stiffened for just an instant. Why, what was this? Arturo moved. He put his foot upon the rail. For a breath, he seemed to hesitate. Was he executing his compact with Nereid? I think so. But perhaps, there at the last as he hesitated, he was fighting with the lure. His foot was on the rail. He plunged. There was a little splash as he struck the water! I waited. One has not long to wait for a swimmer to come up. I called: “Arturo! Arturo!” I crossed the narrow deck, rushed to the bow--to the stern. I called frantically: “Arturo!” My running footsteps, my frantic voice brought Dr. Plantet and Polly. She called wildly: “Arturo! Arturo dear--” We hurried below, and too late now, we plunged the Dolphin. But there was nothing. Down to our limit of two thousand fathoms there was nothing but the dark, turgid mystery of the sea. * * * * * I come now to that curiously inactive year during which, had we not seen what with our own eyes we saw, all the strange events I have so far described might have been the figment of our imagination. The public knew nothing of the details, of course. And even the governments and scientists before whom we laid our report were dubious of our veracity.