"Do you mean that he's dead?" asked Ned, a shiver running through his body as he spoke.
"I'm afraid so," was the reply. "We got you out just in time. You would have perished in a moment more."
"Dead!" said Ned. "Lieutenant Scott dead! And he was so gay and so full of life a few moments ago!"
Jack, who had left the little group a moment before, now returned.
"The poison seems to have evaporated from the interior," he said, "so we may as well go below. I'll go ahead and turn on the lights." The body of the naval officer lay in a huddle at the foot of the stairs leading to the conning tower, just far enough to the rear so that the free passage was not obstructed. With all the lights turned on and every aperture which might transmit a ray to the world outside closed, the boys, after placing the body on a couch, began a close examination of the boat.
There were no wounds on the body, so it seemed that he had died from suffocation. There was still a sickening odor in the boat, but the constant manufacture of fresh air was gradually doing away with this.
The door to the room where the dynamos and the gasoline engine were situated was found wide open, and Ned instructed the boys to leave it so and leave everything untouched.
"The first thing to do," he said, "is to discover any clues the assassin may have left here. It is an old theory that no person, however careful he or she may be, can enter and leave a room without leaving behind some evidence of his or her presence there. We'll soon know if this is true in this case."
"There was some one in here, all right," Jimmie said. "He passed us on the conning tower, skipping like to break the speed limit for the city. I tried to trip him as he passed me, an' got this."
The lad turned a bruised face toward his companions. In the confusion no one had observed the cut on his cheek.