“Yes, he would,” Jupiter said grimly. “Pete, I want you to identify the island of cypresses tonight. We’ll all meet tomorrow morning at Professor Shay’s boat!”

After dinner, Jupiter helped Uncle Titus and Aunt Mathilda decorate the Christmas tree. At ten o’clock the telephone rang.

It was Pete. “It’s Cabrillo Island, Jupe. The old Cabrillo family owned it in 1872. It’s got cypresses all over it. It’s only a mile offshore, about two miles north of our harbour.”

“Good work, Second!” Jupiter said.

He hung up and went upstairs to his room. Before switching on the light, he walked over to the front window to look at the Christmas lights of Rocky Beach. Many of the houses on the other side of the salvage yard were colourfully lit.

He was about to turn away when a faint flash of light caught his eye. He stared in its direction, and saw another flash, and another. Jupiter looked puzzled. There were no houses where the flash came from. As the flashes of light continued, he suddenly realised their source — the salvage yard, just where Headquarters was hidden!

The flashes were coming from inside Headquarters—through the skylight in the trailer’s roof!

Quickly Jupiter slipped downstairs and across the street to the salvage yard. The front gate was properly locked. He turned and ran to the corner where his workshop was. Here was another secret entrance to the yard — two loose boards in a section of green-painted fence.

Cautiously Jupe climbed through Green Gate One into his workshop. He saw that the flashes of light had stopped. No one was near Tunnel Two. He crept round some piles of junk to check Easy Three.

The old wooden door of Easy Three was broken open, and beyond it the trailer door stood ajar!

Inside the trailer Jupiter saw Angus Gunn’s journal on the desk where he had left it. It was open to the last entry. He knew then what had caused the flashes — someone had broken into Headquarters and photographed the journal!

Jupiter wedged the Easy Three door back into place and walked slowly home. Now someone else knew Angus Gunn’s last course!

A mist hung over Rocky Beach harbour the next morning as Pete, Bob, and Jupiter cycled up to the marina. Cluny was already waiting with his bike at Professor Shay’s boat. The red-headed boy was shivering in the clammy cold, but he grinned when he saw The Three Investigators.

“I’ve been thinking all night, fellows,” Cluny said, “and I’m sure the ‘load’ in old Angus’s boat was the treasure! I know we’ll find it today!”

“I do feel optimistic, Cluny,” Jupiter agreed. “It would —”

Professor Shay’s station wagon drove up and screeched to a stop. The pink-faced little professor jumped out and ran up to the boys.

“Sorry I’m late, boys, but there was trouble at the Historical Society this morning. Someone broke in and tried to steal the Argyll Queen file! A man with a black beard!”

“Java Jim!” Pete and Bob cried together.

Professor Shay nodded. “Sounds like him to me.

“But why?” Cluny wondered. “Everyone knows all about the Argyll Queen’s story.”

“Unless everyone overlooked something,” Jupiter said. He told them about the intruder who had photographed the second journal the night before.

“Then Java Jim has the journal now!” Professor Shay cried. “He may be ahead of us, on the island already!” He looked out at the sea through the mist. “But can we sail in this weather, boys?”

Pete nodded. “Visibility’s over a mile offshore — the fog doesn’t thicken until farther out. It’s like that most of the time round here. And your boat’s big and sturdy.”

“Then let’s hurry, boys!” Professor Shay said.

They piled on to the broad, 25-foot sailing-boat, and Professor Shay started the auxiliary engine. Soon they had left the harbour. Pete took the helm and set a course north. Professor Shay and the three other boys huddled in the cabin. Even their heavy sweaters weren’t enough protection against the December morning chill.

“Cabrillo Island didn’t have a name until 1890. Then it was named after its owners,” Pete explained. “It’s a really small island, abandoned now. There’s a good cove on the near side.”

There was little wind, so Pete continued to use auxiliary. The others remained below until Pete said, “There it is, fellows!”

The small, high island loomed up a mile ahead in the mist. As they came closer, they could see the cypresses on it, and a tall chimney that jutted up behind one of the island’s two hills. It was a bleak and rocky place, ghostly in the mist. A solid bank of fog lay beyond it, out at sea.

Pete steered into a sheltered cove on the mainland side, and they tied up to a rotting old pier. They all scrambled out and stood on the shore looking at the barren, rocky land. Here and there grew stunted old cypresses with sparse foliage. The trees had been twisted into grotesque shapes by the winds.

“Gosh,” Bob said in sudden dismay, “if old Angus did bury the treasure here, how do we find it after a hundred years? It could be anywhere!”

“No, Records, I considered that all last night,” Jupiter said. “I’m convinced that Angus wouldn’t have buried the treasure. First, he knew that the Captain of the Argyll Queen was after him, and newly dug dirt is easy for anyone to see. Second, he wanted Laura to find it, and even a few months could obliterate all traces of something buried.

“No,” the stout leader of the trio went on, “I think he would have hidden it somewhere, but marked it with a clear sign that Laura would recognise. A sign that would last a long time, because he couldn’t be sure how long Laura might take to find it!”

Cluny had an idea. “Could Angus have built something here for Laura? Maybe bought some land on the island as a surprise?”

“Yes, I’ve thought of that,” Jupiter said. “We’ll look for something built of timber, or something identified with the Gunns.”

“The letter says to follow his course and read what his days built,” Bob said. “That’s the general direction. Then it talks about the phantom and a mirror. Those could be the signs!”

“Exactly!” Jupiter said. “But the journal says Angus made some proposal to the squire of this island — maybe for permission to hide something here! So we’ll look at the house with the chimney up there first. There could be records in the house.”

They climbed up the saddle between the two small hills, and reached a sheltered hollow near the top. The chimney stood tall in the hollow-but nothing else! The chimney, a massive stone fireplace, and a stone hearth, surrounded by bare, rocky ground.

“The house is gone,” Pete moaned. “There goes our chance of finding a mirror or records, Jupe.”

“Look!” Bob pointed.

Fresh dirt outlined a big, flat slab in the centre of the stone hearth. The slab had evidently been pried up, then dropped back into place.

“Someone’s been here ahead of us,” Professor Shay cried. “Not long ago from the look of that dirt!”

They looked uneasily round at the bleak hills and twisted cypresses. Nothing moved but streamers of mist.

“Let’s see what’s under that slab,” Bob said.

He and Pete moved the heavy stone slab away. Everyone looked down into an empty hole.

“Nothing in the hole,” Pete declared, “and I don’t think there ever was — at least recently.

The dirt’s dry and loose, with no marks in it, fellows.”

“But someone thought there might be,” Jupiter said. “See, he scraped dirt from the hearth until he found the slab.”

“There wasn’t another boat in the cove,” Pete said, “but there’s a small beach round a point just beyond the cove.”

“We’ll spread out and find him!” Professor Shay decided. “But be careful. I’ll be in the centre. If you see anyone, yell, and run to me.”

“Look for anything that might be a sign, too,” Jupiter added. “Maybe a cave, a pile of rocks, or something carved in rock.”