Appleton, Victor – Tom Swift Jr 23 – And His Aquatomic Tracker

A small toggle switch could be flipped to change from manual steering to automatic pilot. Tom also pointed out tape reels for recording all data.

The test got underway after lunch. Hank had

92 AQUATOMIC TRACKER

taken off from the island two hours earlier in a hydrolung suit. The Sea Hound submerged and started cruising to pick up his trail. Tom grinned as he watched the lights on the element panel.

“It’s a cinch: The thallium traces from his Tomasite plastic suit are a dead giveaway. So’s the selenium from his solar-charged battery.”

As Tom tuned the TC and switched to autopilot, the Hound circled to ferret out the center of diffusion. Then its course straightened as the tracker “locked on” to the hydronaut’s trail.

After heading out to sea, Hank’s trail zigzagged and gradually curved back toward Fearing Island. Suddenly Tom frowned.

“What’s wrong, skipper?” Arv Hanson asked.

Tom pointed to two lights on the readout panel. “Traces of nickel and cadmium. Could be from battery-operated gear-but not Hank’s.”

The strange indications mingled with Hank’s trail. Was it an enemy? The course veered from Fearing and led toward the mainland. Tom grew worried as the traces persisted. As they neared the beach, he surfaced and took to the air.

Ahead, on the shore, lay a man’s body, sprawled near the mouth of a rocky inlet I

“It’s HankI” Arv cried out.

CHAPTER XI

THE SHARK MAN

THE figure was unmistakable-clad in hydrolung gear with the hood unzipped.

Tom landed the Sea Hound quickly on the beach while Arv radioed Enterprises for help. In a moment they were at Hank’s side. Tom bent over him anxiously and checked his pulse and breathing.