and Tom noticed with his fright-filled eyes that above them was poised an indistinct, cigar-shaped object, the same torpedolike affair he had seen lifted from the sewer, and he realized that somehow, by some means, the men were dragging this along with them into the dim, green distance.
He was aroused by Rawlins’ whisper and a touch on his arm.
“I’m going to follow,” were the barely audible words. “No danger. Must see where they go. Come on.”
Recovering from his fright, now that the divers were retreating, and rather reassured by the sound of his companion’s voice and words Tom moved forward from the wall but still grasping Rawlins’ hand.
They could not see the figures before them, for the muck stirred up by the others’ passage concealed them as effectually as a smoke screen, but it also served to betray their whereabouts and to conceal Tom and Rawlins as well. For some distance—several hundred yards Tom thought—they moved along, following close to the wall that bounded the shore and ever with the slowly drifting
column of muddy water to guide them.
Once or twice the murk seemed to drift away, and each time Rawlins instantly halted, waiting to see if those they were trailing had come to a stop, but each time the mud again rose before them and they resumed their way.
Tom had no idea of the distance or direction they had traveled. The effort he made to walk was his only guide and he knew that the same effort, the same number of steps on land, would have carried him a long way, but he also knew that under water his progress was snail-like, that a step might carry one a few inches or several feet or not at all, depending upon the current, and he wondered vaguely if Rawlins knew his way, if he could find his way back, or if he intended to bob to the surface to get his bearings when he finally decided to return to the dock. And Tom smiled to himself as he pictured the looks of surprise, the screams of fright which would greet their unexpected and sudden appearance if Rawlins did this and they should bob up beside some crowded recreation pier or ferry ship. But Rawlins had halted again.
Before them now the mud was thinning out, the water was being swept clear of silt and Rawlins drew Tom beside him behind a huge block of stone which had been dumped at the base of the wall. Slowly and gradually the water cleared. It was evident that those they were following were no longer stirring up the mud and so must have come to a stop and, as the sediment drifted off and the dim green light filtered through the water, Tom peered into the vast illimitable void. It was like looking through thick green glass or like glass made half-opaque by one’s breath upon it and for a time Tom could see nothing. Then, as the water became still clearer, he saw the faint outlines of timbers and spiles and a dark object looming ominously, like a cloud, which he recognized as the bottom of some vessel. Against the lighter water over his head, a shadow passed and the greenness quivered and wavered and he knew a small boat was being rowed above them; but no sign could he see of those they had been following.
Then Tom noticed something else, something that rose above the dark bottom of the river as a darker mass, something that resembled a great