Part 24 (1/2)

”Got it, skipper,” Arv said tersely. ”It'll take overtime to set up the job in the plastics department. But we ought to be rolling out the sheeting Tuesday.”

”That's swell, Arv! Thanks!”

By midmorning Tuesday, Tom had his quality a.n.a.lyzer sonar completed and was showing Bud how the units worked.

”Boy, it looks simple enough the way you explain it, prof!” Bud said admiringly. ”How soon can we try it?”

”Depends on Arv,” Tom replied. He picked up the phone and called the plastics department. To his delight, the sheathing was already being rolled out in quant.i.ty. Arv promised that by noon he would have enough of it available to coat a jetmarine.

”Nice going!” Tom said. ”Shoot it out to the cargo-jet hangar as soon as it's ready!”

Soon after lunch, Tom, Bud, and Arv took off for Fearing Island. When they arrived at the base, the plastic coating with its myriad tiny ”mikes” and ”speakers” was speedily applied to a jetmarine under Arv's supervision. Tom, meanwhile, wired the control unit and also installed the a.n.a.lyzer sonar in the _Sea Hound_.

”Want to be 'It' for another underwater game of hide-and-seek?” Tom asked Bud with a grin.

”Sure, but don't tag me with a torpedo!”

Minutes later, the jetmarine slipped off into the depths with Bud and two other crewmen aboard. Tom and Arv followed in the seacopter. The quality a.n.a.lyzer sonar worked even better than Tom had hoped. He not only tracked the jetmarine on its outward course, but located it three different times after shutting off the a.n.a.lyzer long enough for Bud to seek a new location.

”How'd you like to relieve Hank in the South Atlantic?” Tom asked Bud upon their return.

Bud gave a whoop of excitement. ”Roger!”

Tom slapped him on the back. ”You can take off as soon as your s.h.i.+p's provisioned. I'll join you later--but first,” Tom added mysteriously, ”I have another job to attend to.”

CHAPTER XVII

A MISSING AMULET

Bud's curiosity was instantly aroused. ”Don't tell me you have a new trick up your nautical sleeve to fox the Brungarians?”

Tom grinned. ”That's the general idea. I hope to give hydrolung divers the same protection that your jetmarine has.”

”You mean make them invisible to sonar?”

”Yes,” Tom replied, ”and also give them personal spy gear to probe the waters around them and spot an 'undetectable' enemy.”

Bud whistled. ”Do that, and I'll say you're _really_ a magician, skipper!”

Tom himself transferred the a.n.a.lyzer from the _Sea Hound_ to Bud's jetmarine. On a chance that it might become necessary to operate at greater depths--either in searching for the lost missile or in shadowing the enemy--Tom also a.s.signed Arv Hanson the job of rigging the _Sea Hound_ and another seacopter with his new inventions.

Four crewmen volunteered for the cruise. When the jetmarine was ready, Tom and Bud exchanged tight handshakes.

”Good luck!”

”Thanks, Tom.”

The young inventor waved as Bud disappeared down the hatch. As soon as the craft had submerged, Tom went back to Shopton. That evening the Swifts were enjoying a quiet dinner at home when a loud, growling buzz shattered their mealtime conversation.