When Linda Carlton and Dorothy Crowley left Jacksonville Airport on the morning of June twenty-seventh in the Ladybug, and flew into the Okefenokee Swamp, they fully expected to telephone to their families that night, or at least to send a wire to them, as they had promised. So when Miss Emily Carlton heard nothing from her niece she became anxious, and directed her chauffeur to drive her to Mrs. Crowley's cottage.

Both women were established at Green Falls for the summer, which was the favorite resort of all Linda's friends from Spring City. It was there that the girl had called her aunt from Jacksonville, the night that Dot and the Mackays had arrived. Only one telegram had she received since that time.

Mrs. Crowley, who was less inclined to be nervous than Miss Carlton, tried to reassure the latter, saying that she realized how busy the girls would be. But when June twenty-eighth passed without any word from them, she too became alarmed, and together the two women put in a long distance call to Captain Magee at Jacksonville.

Briefly he told them what he knew—of Linda's decision to go "scouting," as she called it. And of her request for the revolvers.

The shock of that piece of news was almost too much for Miss Carlton. She jumped to the conclusion that the girls were dead.

"Aren't you doing a thing to find them, Captain?" she demanded, harshly.

"I was thinking about it," he replied. "But after all, they've only been gone two days——"

"You don't know my niece!" interrupted the unhappy woman. "Linda always wires or telephones me every day, when she goes on these flying trips. She doesn't forget. It's because she can't—she has been injured or killed!"

"I hope not," he replied. "But I will send a plane over the Okefenokee Swamp tomorrow, Miss Carlton," he promised.

The two women gazed at each other in helpless dismay at the conclusion of this conversation. What could they possibly do, aside from informing the newspapers—a decision which they carried out immediately.

Accordingly, on June twenty-ninth, every newspaper in the country stated the fact that Linda Carlton, the famous aviatrix who had flown to Paris alone, was missing again—somewhere in Georgia—probably in the Okefenokee Swamp, with a chum, Miss Dorothy Crowley of Spring City, who was also a pilot.

The unhappy news instantly produced the effect which Miss Carlton hoped it would accomplish. It aroused no fewer than five searching parties, all bent upon locating these two popular girls.

Captain Magee's men were the first to go. Summoning Sergeant Worth, he commandeered a plane from the airport, and directed the pilot to fly over the swamp, searching from the air by means of spyglasses.

The second party was composed of the girls' fathers, both of whom were in New York City at the time. Mr. Crowley telephoned Mr. Carlton, and after sending a wire to their families, they boarded a Florida train together.

The third volunteers were two young men at Green Falls, two college boys who considered Linda and Dot their special girl-friends, though neither of them was engaged, Jim Valier and Ralph Clavering heard the sad news at the out-door pool at Green Falls, just as they were about to join a group of young people for a swim. Kitty Hulbert, Ralph's married sister, read the head-lines aloud.

"Jim," muttered Ralph, when Kitty finished, "let's do something! We can take a plane to Florida—and go on a search from there."

"O.K.," agreed the other boy, and quietly and quickly the two young men disappeared from the group.

The story came to the Mackays in Washington, where Ted had business on his return from Georgia. The instant that Louise read it, she jumped up in excitement.

"We must go, Ted!" she cried. "You can get your vacation now."

"I'll wire immediately," he agreed, without an instant's hesitation, and he went out to make the necessary arrangements and to order his plane in readiness.

The fifth and last party was none other than Linda's two latest admirers, the two young men she had mentioned to Dot in the hope of a rescue—Jackson Carter and Hal Perry.

All in all, it ought to have been enough to satisfy Miss Carlton that every effort was being made to find the girls and to bring them back to safety.

The airplane from the police department was the first of these groups to get into action, the first to enter the swamp. Yet it did not actually enter it, but merely flew above it, for the pilot, less experienced than Linda herself, did not believe it possible to come down on one of those islands. For hours, however, he circled about, over the bog, and the cypress-trees, while Sergeant Worth in the rear cock-pit scanned the landscape with his spyglasses. But neither man saw any trace of the autogiro or the girls, and late that afternoon they had to return in discouragement to Captain Magee.

"I couldn't even locate that camp on the island," Worth said. "The one where we got the prisoners, you know. Unless you have the exact directions, it's hard to find anything in that swamp.... And—I don't see much use in trying again."

Captain Magee looked exceedingly grave; he was genuinely worried. He blamed himself for letting the girls go alone. But there had been nothing official about the project—he had not really expected that they would run into the criminal. Besides, Linda Carlton had seemed so capable, and both girls were so eager to go.

"We mustn't give up, Worth," he said quietly. "It's more important to find these girls than a dozen criminals. We owe it to them, to their families—to the whole country. Everybody has admiration and affection for Miss Linda Carlton, after all she has done.... You'll have to go back tomorrow—or get another man, if you feel too discouraged."

"No, I'm only too glad to help," the other assured him. "I would do anything in the world for Miss Carlton. But I don't see how it can do any good. A scouting party in boats would be much more likely to be successful."

"We'll try that, too, as soon as I can get some men together. But tomorrow you fly out over the ocean to that island where the thieves had the jewels. The girls might be stranded there. Take another pilot, and a bigger plane."

Worth looked doubtful.

"We haven't any way of locating that island, either," he said. "It was Miss Carlton who took us there before, and I have no idea where it is."

"Just do your best, Worth," urged the Captain. "Fly around all the islands near the Georgia coast, keeping a sharp look-out for the autogiro."

"Rain or shine? It looks like a storm tomorrow."

"Yes, whatever the weather, you must go—or get someone else."

So, in spite of the terrible downpour and the high winds of June thirtieth, a cabin monoplane flew across Georgia and out over the ocean to a group of islands just off the coast. Three men were aboard—two experienced pilots, one of whom was also a mechanic—besides the police officer.

Leaving the coast behind, they flew out into the grayness that was ocean and sky. The waves were high, the sea rough and angry, and the rain was coming down in sheets, blinding their vision, but they pressed on, two of the men keeping their spyglasses on the water, watching for islands. They passed over several, but they were small, with little or no place to land. Eagerly the men watched for some sign of human life, some signal, some glimpse of the autogiro.

"They'd never be alive if we did find them," remarked Worth, gloomily. "And if they did run into that gangster, he'd surely have made away with them."

"If only it would clear up," grumbled the pilot. "So we could see something!"

They were flying much lower now, for it was comparatively safe over the water, and despite the weather, they were able to spot the islands. All of a sudden the mechanic uttered a sharp cry.

"There she is! Look! Over there!"

"Miss Carlton?" demanded Worth, excitedly. "Where?"

"Not the girl! The plane—the autogiro! See—that island to the west! See the wind-mill on top?"

"By George! You're right!" agreed Worth, a thrill running up and down his spine. Thank Heaven, he hadn't given up!

The pilot directed the plane over the island and circled about, landing finally some distance from the autogiro. A glance at the latter assured them that it had not been wrecked. Why, then, hadn't the girls come back? Was it possible that all this scare had risen to alarm the world for the simple reason that Linda Carlton had run out of gas?

The three men climbed out of the cabin and shouted as loud as they could, since the girls had evidently failed to hear their plane, above the noise of the storm and the roar of the ocean. Eagerly they waited for a reply. But when none came, fear crept over them all.

Had the girls died of starvation, or was there foul play of some kind? With gloomy forebodings, they walked about the beach, seeking evidence of some kind to tell the story of what had happened.

Finding nothing, the mechanic began to examine the autogiro. She was undamaged, unhurt—everything in order, gasoline in the tank. The engine started easily in answer to his test, and ran smoothly until he turned it off. No, the gallant little Ladybug could not be blamed for whatever disaster had taken place!

Then, forgetful of the weather, the three men set out to search the island thoroughly. Buckled in oil-skin coats, they felt protected themselves, but Worth shuddered as he thought of these girls alone in such desolation, with no roof to cover them, no food to satisfy their hunger, or water for their thirst. Gloomy and discouraged they plowed through the wet sand, calling the girls' names. Finally, abandoning the hope of finding them alive, they set themselves to the gruesome task of looking among the underbrush for their bodies. At last they gave up.

"We'll fasten a canvas sheet over these bushes, so that we can locate the island, and we'll pin a note on it to say that we'll be back," decided Worth, "in case they are alive. One of you men take the autogiro, and the other the plane, and we'll go back now."

The rain was abating somewhat, and the two planes made the return trip without any mishaps, arriving at the Jacksonville Airport before dark that evening.

A wildly enthusiastic crowd, which had collected in spite of the weather, greeted them with resounding cheers. The Ladybug was back again—safe and sound! Women cried with joy, men threw their hats into the air, children clapped their hands and whistled. In a miniature way it was a demonstration like the one given Lindbergh upon his arrival at the French Flying Field. But it was a false rejoicing, and the gayety was quickly changed into despair when the pilot reported that the girls themselves had not been found.

Weary and disappointed, the crowd turned away, and Sergeant Worth told the sad story to the newspaper reporters who waited to interview him, before he returned to the police headquarters.

Captain Magee was terribly affected by the news. Linda Carlton might have been his own daughter, from the grief which he could not conceal.

Two well-dressed young men were waiting in his office when Worth arrived, and they listened to the grim account. They were the first of the rescue parties to arrive from the North—Jim Valier and Ralph Clavering.

"These two young men are friends of Miss Carlton and Miss Crowley," explained the Captain. "They want to go into the swamp tomorrow in a boat.... Perhaps the girls have reached the main-land, or perhaps that autogiro was stolen, and they never were on the island at all.... Anyhow, we'll search the swamp again. Will you go with them, Worth?"

"Certainly," agreed the sergeant, though he felt as if it would be fruitless. Those girls were at the bottom of the ocean, he was sure!

"A light motor-boat ought to be able to go up that little stream," continued the Captain. "I will have one ready at the edge of the swamp tomorrow morning at ten o'clock. If you young men will come here at nine, I'll send you over there in a car."

Jim and Ralph expressed their thanks to the officer, and promised to be on hand at the arranged time in the morning. But, like Sergeant Worth, they were exceedingly discouraged; they had little hope of success.

When they awakened the following morning, which was the first day of July—the day that Linda should have reported to Atlanta—they found that it was still raining, although the storm had ceased, giving way to a dismal drizzle. What an unpleasant day to start off on an excursion like theirs, that was gloomy at best! Yet the weather did not deter them from their purpose, nor did it stop Hal Perry and Jackson who started earlier that morning in their canoe.

But it was difficult with a motor-boat, and all three of the men were unfamiliar with the swamp and its little streams. No one knew where to turn off, as Jackson and Hal had learned from many vacations, and after pushing ahead for two or three hours, they found themselves off their course—grounded.

"It's no use," muttered Worth. "We can't make it in a motor-boat. Magee's never been in the swamp, or he would have known. We'll have to turn back and get a canoe!"

"A whole day wasted!" growled Ralph angrily, as if it were the sergeants fault. "A day! When every minute is precious!"

"Well, it's nobody's fault," remarked Worth. "The sooner we get back the better."

"Nobody's fault!" repeated Ralph. "No—ignorance is O.K.—if it pertains to the police! They shouldn't know a thing about the country around them!"

"No use getting mad at policemen, Ralph," drawled good-natured Jim Valier. "Haven't you learned from driving a car that it doesn't pay? Besides, they're always right."

"No, we're often very wrong," said Worth, humbly and seriously. "And maybe you don't think I care, Mr. Clavering, about finding those girls. But I do! I haven't thought about a thing but that for the last three days."

Ralph made no answer, but applied his attention to searching the landscape with his glasses. But, like everybody else thus far, he found nothing.

Discouraged and silent, they managed to push the boat into the deeper water and to turn it around. All that afternoon they spent in retracing the progress they had made, and returned to the Captain's office just before supper.

"You want to try it again in canoes?" asked Captain Magee.

"Yes," replied Ralph. "Without any of your police this time. No use taking an extra man—it only means more provisions to carry."

"True. But you must be careful of snakes and alligators."

The boys looked none too pleased at the idea, but when they remembered that Linda and Dot, if still alive, would be subjected to the same perils, they were all the more eager to go.

This time, they decided, they would do it scientifically; they would go prepared with a map of the swamp, equipment, food, and rifles. And above all, a compass! And they would not give up until they had searched every part of that dismal Okefenokee Swamp!

So, cheered by the optimism of youth and the promise of another day, the boys slept well that night.