Jep Dee stirred impatiently, demanded, "Who is Ham?"

"Another man who is helping us," Doc explained.

A bit later, Monk leveled a hairy beam of an arm.

"There she be," he said.

IT was not a mile long. It was not half a mile wide. It somewhat resembled a green doughnut out of which someone had taken a bite.

Doc Savage said, "We might as well land in the lagoon." The lagoon, of course, was the water in the center, the hole in the green doughnut.

Jep Dee said, "Come in from the north. They're on the south side."

"The lagoon safe?"

"Nothing is safe down there," Jep Dee said grimly. "But they won't be watching the lagoon. It's mostly shoal, not more than a foot or two of water. Do you have to come in through the entrance?"

"No."

"That's good," Jep Dee said. "They've got one of those electric eyes set across the entrance. That's what caught me.

Can't even a rowboat come into that lagoon without breaking the electric-eye beam and giving an alarm."

Monk said, "They must have the place all fixed up."

"Fixed up is right!" Jep Dee swore for a little while. "Wait until you see the cache!"

Doc Savage cut the plane motor, set the ship gliding at as slow a speed as possible, to keep down wind noise from its flying wires. He nosed it in to the island from the north.

Spray sheeted from under the floats when they touched; then the plane settled. The lagoon was gla.s.s-smooth; thereseemed to be no wind whatever.

"Break out the paddles," Doc directed.

They were regular canoe paddles, capable of driving the small plane after a fashion. But before they paddled far, they discovered that it was simpler to drop off in the water, hardly more than knee-deep, and shove the plane.

They pushed the plane to the mangroves, found a small indentation, backed the craft into that and tied it there, poised with its nose toward the open lagoon, where it could be unlashed quickly for flight.

Jep Dee muttered, "What about me? I don't want to give the idea that I'm a coward, but I don't like the idea of being left alone in this plane. I can't fly it, even if I wasn't blind."

"We will leave you in the mangroves," Doc told him.

They left him concealed among high mangrove roots, with an emergency kit of blankets and food from the plane.

Before they left him, he asked a question.

"What's the matter with this other guy with us?" Jep Dee demanded peevishly. "Why ain't he said nothin'?"

Monk said, "He got smacked in the neck with a fist, and it hurts him to talk."

Jep Dee seemed satisfied.

Doc Savage led Monk and Senor Steel into the mangroves.

"The schooner will be here soon," the bronze man explained. "When they take the prisoners off, we might as well follow them. Be a simple way to find the cache."

Senor Steel spoke quickly. "I can think of a better way."

Doc studied the man in the moonlight. "Better way?"

"The cache," said Senor Steel, "is located on the very southern tip of the island, where there is high ground and some palm trees. It will save us time to make directly for it."

Doc Savage said, "You seem to know a great deal about the island."

"One of my agents reached it, and got away, without finding out the exact location. He stowed away on Horst's schooner speedboat."

"Agent?"

"You seem to have met him," Senor Steel said.

Doc made his voice puzzled. "I have met one of your agents?" he asked.

"Henry Peace," said Senor Steel.

"Henry Peace is one of your agents?"

"Exactly."

Chapter XVI. MUD.

AT first, there was mangrove swamp around them, the earth being boggy and in some places covered with water. It was tidal flat that flooded at high tide, and the tide was out now; so that the mangroves, for a foot or so above the mud, were slimy and slick. They heard, occasionally, small sharks make splashing sounds in the pools, and crawfish sometimes fled with furious skittering noises in the shallow water.

Once Monk slipped off a mangrove stem, landed on his head in mud which was semiliquld and about three feet deep.

He had to have Doc's help to extract himself."Brothers," he said, "some day I'm gonna give up this hero business and settle down to a peaceful life of finding out what's in test tubes."

They reached the path shortly after that. It was on higher ground, where there were palms, palmettos and a few trees of the tropical evergreen variety.

"Boy, here's easier going!" Monk gasped gratefully.

He would have started along the path, but Doc gripped his arm, stopped him.

"Let me examine your machine pistol," the bronze man requested.

"It's in working order," Monk said.

"We are going into action," Doc reminded him. "Let's be sure."

Monk drew his machine pistol and pa.s.sed it to the bronze man. They stood close to the high palmettos and shrubbery that lined the path. The shadows were like blobs of oil smoke that were standing still.

Faint clicking noises indicated Doc Savage was unclipping the ammunition drum from Monk's pistol and scrutinizing it.

"All right," he said. "You have plenty of spare ammo drums?"

Monk's pockets were full of mud.

"The drums are probably muddy as blazes," he said, and felt of his pockets.

He gave a great, dismayed start.

"Gleeps!" he exploded. "I haven't got a single spare ammo drum!"

Doc Savage said, "You probably lost them when you fell into the mud."

Monk made mutterings of disgust, took his machine pistol when Doc Savage handed it back to him.

The bronze man now spoke quietly.

"You and Senor Steel will remain here," he directed. "You need a breathing spell, after going through those mangroves. Too, we should scout this path. It would be poor strategy for all of us to do that-if there should be a trap, we would all fall into it."

"That is true," Senor Steel said in a rather strange tone.

"Wait here," Doc repeated.

The bronze man vanished in the shadows.

HE went quietly. He followed the path about twenty yards, turned off, headed back toward where they had left the plane.

Monk, who'd had so much painful trouble with the mangroves, would have been amazed at the speed of the bronze man's movements across the swamp. Probably he would not have been surprised-he knew all about the bronze giant's almost uncanny muscular agility.

Jep Dee crouched where he had been left.

"Easy does it," Doc told him quietly. "I decided to move you."

"Why?" Jep Dee asked.

"Rigging up a little surprise party," the bronze man explained cryptically.He moved Jep Dee a considerable distance from where he had been located, and left him on higher ground, lying in a trench in the sand which was quickly scooped out by hand.

"Be back in a minute," Doc said.

He went to his plane. Still intact in the baggage compartment were equipment cases-a standard outfit of gadgets which the bronze man and his aids always took with them when setting out on an adventure. Gas masks and the little anaesthetic gas grenades were a part of the equipment.

Doc Savage distributed gas grenades about the plane, placing them so that the ship could hardly be approached without the gas being released.

On the handles of the cabin door, on the controls themselves, the bronze man smeared a sticky liquid which was hardly noticeable. The liquid was an anaesthetic, too, that penetrated the pores of the hands; and while anyone handling the plane controls might not get enough of the stuff to cause unconsciousness, it was sure to deaden their arms, make them feel very ill, and create a good deal of worry.

He smeared more of the sticky liquid on the surrounding brush, on the plane guy lines.

Then he went back to Jep Dee.

Giving Jep Dee a gas mask, Doc Savage explained about throwing the anaesthetic gas grenades. He put a supply close to Jep Dee's hand.

"If anybody comes, how'll I tell whether they are enemies?" Jep Dee asked. "I can't see."

"They will say, ' The sand is green,'" Doc Savage explained. "That will be the pa.s.sword. Unless they give it, cut loose with the grenades. But put on the gas mask first."

Having given Jep Dee a gas mask he showed him how it worked.

Then he made a round of Jep Dee's hiding place and distributed more of the sticky liquid on the mangroves, where anyone trying to creep close to the spot would be fairly sure to get into it.

When the bronze man approached Monk and Senor Steel, he could tell that they were getting impatient.

He did not show himself, did not let them know he was near.

"About time Doc was gettin' back," Monk said uneasily.

Doc Savage now began his examination of the path. He went very slowly, searched with the utmost care, for he distrusted almost everything upon this island.

The death trap that he found was ingenious.

It functioned if one did not carry some kind of a projector that turned strong ultraviolet light upon the receiving cell of an electric eye. There was an electric-eye beam across the path; if the beam was interrupted, a machine gun began firing at once, swinging a little as it fired, to rake the path thoroughly.

Doc got acquainted with the whole grisly trap.

He put his hand over the electric eye, from a safe spot.

The machine gun cut loose deafeningly, and its lead mowed down mangroves. It fired perhaps two hundred shots. Then it stopped, empty.

Doc Savage went out in the path and lay down where he might have fallen if shot. He carried a fountain pen with red ink, and he spread the ink on his face and clothing in realistic splotches.

MONK MAYFAIR heard the machine-gun roar, jumped to his feet.

"Doc!" he gasped. "Something has happened-"

He did not finish, because Senor Steel hit him. Senor Steel used his fist, and he set himself carefully, because he could see that Monk had an iron jaw. The blow sounded like an axman's first hard cut at a tree.

Monk jerked very stiff and rigid and fell, as the tree would fall, backward.

Senor Steel did not have a gun. He'd had a gun at the hotel penthouse in Key West, but he'd been able to find no trace of it after he regained consciousness there, with Doc Savage in the same room.