Rick sighed. "Just our luck he doesn't want us in the case. Wouldn't it be great to work with the Navy frogmen? We could learn plenty."

"Forgetting St. Francis?" Scotty inquired. "There he lies, twenty fathoms down, probably covered with barnacles and waiting to be rescued.

And you want to go fogging off with the frogmen."

"All right, all right! Don't rub it in. We'll go back to being interested in the bark _Maiden Hand_. And St. Francis. And pirates.

Let's cast off, my hearty."

The Danish Pastry was only a few blocks away, and Dr. Ernst and the Spindrifters were already seated. The boys joined them, with apologies for being late, but without mentioning their meeting with Steve Ames.

There was nothing to be gained by bringing the matter up in front of Dr.

Ernst. They could tell Zircon and Tony later. Zircon knew Steve, but Tony didn't.

Over dessert, Dr. Ernst reached into his bag and brought forth a chart.

"I thought you might need this," he said.

It was a detailed chart of Clipper Cay and the surrounding waters. It showed clearly the position of the reefs, and it gave soundings that showed the depths.

Zircon shook his ma.s.sive head. "Paul, your thoroughness has never failed to amaze me. What would we have done without you?"

Ernst smiled his pleasure. "Thank you, Hobart. I try to be thorough.

Besides, I want you all to have a pleasant recollection of the Virgin Islands. We who live here love them very much."

The boys and Tony echoed Zircon's thanks, then fell to a study of the chart.

It was apparent that the water deepened rapidly beyond the western reef.

In a few places, the twenty-fathom line was only a short distance out.

"Have you any idea where this ship went down?" Dr. Ernst asked.

"A bare idea," Tony replied. "It was off the western sh.o.r.e of the island, probably close to the reef, in twenty fathoms. The bark had been hit and was sinking. The captain ran for the island with the hope of beaching the ship on the reef, but he never made it. The bark went down, and Anne Bonney's pirates picked up the survivors."

"We know of Anne Bonney here," Dr. Ernst told them. "You realize that the Virgin Islands were once a hangout for pirates? Oh, we have a dark and b.l.o.o.d.y history, what with piracy, slave rebellions, even Indian ma.s.sacres."

"You'd never know it," Rick said. "This is the most peaceful place I've seen in years."

He didn't add that the peace was only apparent. Steve Ames wasn't needed in really peaceful places. Something was stirring under the tropical calm of St. Thomas.

"Tonight you must have a taste of St. Thomas home life," Dr. Ernst said.

"You shall be my guests at dinner. Dr. Briotti will be interested in my collection of Indian pottery. And you young men will be interested in my wife's hobby, which is fish. She has an amazing collection."

"Alive?" Scotty asked.

"Yes, indeed. In salt-water aquariums. Our misfortune makes it easy. You see, we have no natural fresh-water supplies on St. Thomas. We depend on catching rain for our drinking water. So our plumbing is operated by sea water, of which we have plenty. As a result, Mrs. Ernst is able to have a constant supply of salt water flowing through her aquariums. I know you'll be interested."

The boys agreed. Mrs. Ernst's hobby sounded like fun.

After lunch Dr. Ernst departed for his office, leaving the Spindrift group to their own devices. Not much remained to be done, except for checking in at their hotel. For now, they were content to walk around town.

As they pa.s.sed the post office where Alexander Hamilton had once been a clerk, Scotty smiled meaningfully at Rick.

"Steve lost a tail this morning. Remember?"

Rick looked at him doubtfully. "Of course. Why?"

"Somebody loses, somebody gains," Scotty replied cheerfully. "Don't look behind you, but we've found one!"

CHAPTER III

The Shadow

The two scientists had been walking ahead of Rick and Scotty, but Zircon's keen ears had overheard the boys' remarks. However, he was too wise to make his interest obvious. He waited until the group pa.s.sed a store with a large display, then stopped, as though to examine it.

Rick found himself surveying a collection of tools for the do-it-yourself addict.

"What's this about Steve and a tail?" Zircon asked. He pointed at a power-drill set, as though discussing it. His normally loud voice couldn't have been heard five feet away.

Rick shook his head, then pointed at a different drill set. Anyone watching would have thought the tools were the subject of conversation.

Rick quickly outlined what had happened and concluded, "Scotty spotted a tail on us a few minutes ago. Same guy?"

Scotty bent down for a closer look at a series of wood power bits. His voice was scarcely audible. "Not the same one. This one is a Virgin Islander. Looks like a farmer. When we stopped he walked right on by.

He's out of sight now. But he'll pick us up as soon as we start."

Tony Briotti, to whom this kind of adventure was new, asked, "What do we do about it?"

"Nothing," Zircon answered. "Steve Ames wanted to get rid of his shadow and the boys helped him out. But we have no particular reason for wanting to get rid of ours. Let him follow. Undoubtedly whoever is tailing Steve got interested when they saw him talking with the boys, but they'll learn nothing by trailing us."

"And it's one less for Steve to contend with," Rick added.

Scotty straightened up. "I have to admit this bunch of tools is beginning to bore me a little. Where are we going?"

Zircon shrugged. "I have nothing in mind. We might check in at the hotel."

"I'd rather swim," Rick said.

"Same here." Scotty made a quick survey of the street without seeming to do so. "No sign of our friend. He's probably in another doorway."

"Then Hobart and I might as well check in," Tony suggested. "I'd like a swim, but frankly I'm a little sleepy from too much lunch."

"How about checking in for us?" Rick asked. "Then we could get right into the water. No need for all of us to go to the hotel."

The scientists agreed, and at Scotty's suggestion hailed a taxi. As the car rolled off toward the boat where their luggage was stored, Scotty grinned. "This was the only taxi in sight. Wonder how our friend will manage to follow us?"

He had his answer at the pier. While Zircon was piling their overnight bags into the taxi, a farmer rode past on a bicycle. He didn't look at them. "There he goes," Scotty said. "Pretty easy after all. Guess the town is small enough so he wasn't worried about finding us."

"We'll give him a choice to make when Tony and I leave." Zircon smiled.

"Let's see whether he stays with you, or follows us."