He was on the point of flashing on his own light when Weddigen stopped, tossed the crowbar aside and knelt again over the treasure box. For a time he fumbled in the dark while Jay stood wondering what was going on. Again a flash of light, and in that instant the Brighton youth saw that the other diver was making fast on his salvage lines. Beyond a doubt his plan was to send the treasure chest aloft now that he had worked it close to the door of the areaway where it might be yanked up the companionway and thence up through the depths to the deck of the _Nemo_. "Going to send the rest of the diamonds up and try to get away with what he has already helped himself to," thought Jay as the daring scheme of his fellow diver was now revealed. But Jay had seen all and was determined so soon as he got back on the _Nemo_ to compel an opening of that cunning little pocket on the side of Weddigen's diving suit. But now a real danger confronted the Brighton youth. Suppose Weddigen gave the signal for the diamond chest to be raised away? Deckmen aboard the _Nemo_, when the signal was given, would haul away with all their vigor, eager to perform their part in the salvage of the much desired treasure. Crouched in the areaway outside the cabin Jay would be directly in the line of the treasure chest as it was yanked away. Suppose that iron box came his way? Perhaps it might crash full into his life lines? One swift blow might sever his air hose and leave him helpless against the inrushing water? Or suppose it cut off his signal lines, leaving him powerless to ask for a lift off the ocean bed? There was only one thing to do, and that was to get out of there as quickly as possible. Weddigen would not signal for the strong box to be hoisted away until he, too, was out of harm's way; and Jay, now that he had been an eye-witness to the theft, was determined not to let the other know he had seen the theft until they were back on the _Nemo_ again. As quickly as possible he shuffled along the areaway and began climbing the steps toward the deck of the _Dominion_. He was just in time, too, for a glimmer of light behind him indicated that Weddigen was following close behind. Rather than reveal his presence Jay fumbled along in the darkness, climbing the steps without resorting to the use of his flash. Once on deck he turned sharply aft and moved away from the companionway leading below. In his anxiety to make haste he momentarily let go the state room door by which he had steadied himself and in that instant his feet flew from under him. The slimy deck would have been hard enough walking had the _Dominion_ lay on an even keel; but with the pitch to port the half-rotted flooring was difficult walking for the most experienced and careful diver.