"I'll do my best," he said grimly.

There was no more conversation as the skiff fairly flew on top of the water. Everything went well until they were about halfway home. Danny, who had been turning left and right to avoid the higher dunes, suddenly swerved very hard. He straightened the boat again, but within seconds it rammed into a long sandbank. The motor churned desperately for a moment, then stopped.

The impact had knocked all three girls from their chairs. They flew through the air and landed with a resounding splash in the water!

CHAPTER XV.

Jungle Attack.

DRENCHED with seawater and covered with sand, Nancy, Bess, and George stood up alongside the Pirate Pirate. To Danny's amazement they were not angry. Instead, they started to laugh. George said, "Thanks for the unexpected bath!"

Bess, looking at the skiff, remarked, "I guess we'll have to walk home."

"Or wait for high tide," Danny told her. "Instead of waiting, however, you could walk to that key over there and investigate the wildlife. It isn't far from here."

"Does anyone live on it?" Nancy asked.

"No, it's uninhabited."

Bess chose to stay with Danny and dry out in the hot sun, but Nancy and George were interested in seeing the key, so they sloshed through the shallow water to the mangrove-lined island.

When the girls reached it, they scrambled over roots and coral rocks. There was nothing to see but bushes and trees.

"It's a real jungle!" George said.

"I'll say it is," Nancy agreed. "Look over at that mangrove." She pointed.

George stared in amazement. A fish was climbing up the bark!

The two girls watched to see how high it would go. To their astonishment it disappeared in the leafy foliage above.

"This place is absolutely spooky!" George muttered.

She had barely finished the sentence when they heard a dog barking.

"There must be somebody on this key besides us," Nancy said. "But let's go on. Maybe we'll see something else unique."

The dog's barks were coming closer, and the girls wondered if he were friendly. If not, both of them would have to scramble up the next tree!

They waited for the animal to come closer. When it did, Nancy gasped. He was an Irish terrier, and on his right forepaw were six toes!

"E-fee!" Nancy cried out, recognizing the animal from Crocodile Island. "How did you get here?"

The dog came up to the girls at once, wagged his tail in delight, and barked in short yaps.

"Is your master around?" Nancy asked apprehensively.

The girls stood still, waiting for someone to appear. But no one did. The dog stayed close by, and acted so glad to see them that they were convinced there were no other human beings on the small key besides themselves.

George asked, "Do you suppose someone from Crocodile Island left E-fee here on purpose?"

Nancy shrugged. "If so, it's a pretty poor way to treat the dog. He couldn't swim back to Crocodile Island. It's too far from here."

Puzzled, Nancy and George walked on. E-fee bounded ahead of them. Presently he ran to a little clearing and began to bark frantically. The girls hurried to the spot where he was standing.

E-fee looked up at them, gave a few quick barks, then dug furiously into the sandy soil.

"Nancy, he's looking for something," George said. "Maybe his master is buried here!"

"Horror stories again, eh?" Nancy quipped. But she felt apprehensive herself.

E-fee did not stop digging until he had made a good-sized hole. Then he looked at the girls as if to say, "Go ahead. Take a look!"

Nancy and George stepped forward and gazed into the hole. To their amazement a pistol lay inside!

"Where did that come from?" George asked. "Do you suppose E-fee's master put it there, and then went away, leaving the dog to guard it?"

Nancy thought a moment, then said, "It's a good guess, George. Perhaps the men on Crocodile Island didn't want E-fee there anymore because his barks attracted too much attention. Now that the island is closed to the public, I'd say they don't want a dog calling attention to the place if something illegal is going on there."

George got down on her knees and carefully lifted the pistol out of the hole. She examined it and found that the firearm was not loaded, and the serial number on it had been almost obliterated.

"Let's take it along," she suggested. "If n.o.body owns this island and a person comes here and buries a weapon, then it becomes the property of the finder."

Nancy smiled. "I love your logic. We'll take the pistol with us, but we'll turn it over to the police."

The girls filled up the hole, shoving the sandy soil in place with their shoes. Then they went on exploring. Nancy and George watched for anyone who might be on the island. E-fee followed. Since he did not bark, they felt reasonably sure they were alone.

Presently Nancy noticed that there were many twelve inch lizards running around. Some hid in the undergrowth, but a large number of them were at a fresh-water pond containing hundreds of mosquito larvae. The lizards were eating them greedily.

The girls were so busy watching the fascinating sight that they failed to notice a swarm of mosquitoes coming their way. Suddenly the mosquitoes enveloped Nancy and George, biting furiously! As the girls tried to duck, the insects sang, divebombed, and stung them.

"Oh, dear!" George cried out. "We'd better get away from here fast!"

With E-fee at their heels, the girls ran as quickly as they could. To their dismay the mosquitoes followed!

"This is awful!" George panted. "A real jungle attack. What'll we do?"

"I've heard," Nancy called out, "that the only way to get rid of these pests is to dive into the water."

The two friends hurried toward the spot where they had entered the key. The going was rough. Despite the protection of their shoes they nicked their ankles on coral rocks and tripped on tree roots, which made them wince in pain. The mosquitoes kept buzzing around their heads, necks, arms, and legs, which were fast covered with bites.

The dog had long since outdistanced them and met the girls among the mangroves along the sh.o.r.e. When he saw them dive into the water, which was now deeper, he ran in after them. How good the cool water felt!

Nancy and George swam all the way to the Pirate Pirate. E-fee followed. When they reached the skiff and stood up, Bess exclaimed, "What in the world happened to you, and where did this dog come from?"

Without being invited, E-fee climbed aboard. Nancy said, "He's a visitor from Crocodile Island."

George explained about the jungle attack of mosquitoes, and how they had found the dog.

"Jump in, girls," Danny said. "I have just the thing for you."

He opened the first-aid kit and gave each girl an antihistamine pill, followed by a drink of water. Then he handed them a tube of medicine and suggested that they lather themselves with it They did this and soon the medication began to take effect, making them feel better.

"What an experience!" Bess said. "Tell us the rest of the story."

"We think someone from Crocodile Island buried a pistol there and then left E-fee behind."

"How did you know that?" Danny asked.

"Here's proof." George said, and pulled the pistol out of her pocket.

"What!" Bess shrank back in surprise. "Where on earth-"

"It was buried on the key," George explained, "E-fee dug it up. Since he knew where it was, we figure he saw his master bury it. We brought the pistol to give to the authorities."

"Is-is it loaded?" Bess asked, uncomfortable at the thought.

"Relax. It's empty," George said.

Danny asked whether they intended to return the dog to his master. At once George answered, "Not on your life! I'll find a nice home for him."

Danny said he was glad to hear this because he felt it would be unwise to keep the animal at the Cosgrove home. "Some of your enemies might track it down, and then we'll be in trouble. You might be accused of stealing E-fee!"

"I agree," Nancy said. "Do you think we should drop him off at the animal shelter?"

"That's a good idea," Danny replied.

Nancy now asked, "How about those mosque toes? We have never seen a swarm like that before."

"In Key Biscayne and other inhabited keys they have mosquito control, which takes care of the problem. The insects breed only in deserted little islands like the one you were on. Lizards act as natural balancers."

George remarked, "If they eat that whole swarm, they're sure to have indigestion!"

The others laughed, then Danny said, "Usually mosquitoes are bothersome only during the rainy season. I didn't think you'd encounter any at this time of year."

"All right, we forgive you." George grinned.

"Thanks." Danny now asked, "Do you want to go periscope hunting again or do a little more sightseeing?"

"Neither!" Nancy said quickly. "All I want is a shower and some more of that soothing lotion."

"I second the motion," George added. "Let's head for home."

After the group docked in Key Biscayne, they brought E-fee to the animal shelter. The girls felt bad about leaving him, but just then a woman and her little girl stopped and asked if they were looking for a home for the dog.

"Yes," Nancy replied.

The child was already patting the dog, whose tail was wagging happily. The little girl looked up. "Mommy, can't we take this one? I love him already."

The woman smiled and said to Nancy, "Is he gentle?"

"Oh, very, and a good watch dog."

The little girl gave E-fee a tremendous hug. Her mother said to the man in charge of the shelter, "We'll take E-fee and give him a good home. By the way, what does his name mean?"

"Dog-in Seminole," Bess answered, and the little girl giggled.

Nancy, Bess, and George left the shelter, happy that E-fee would be living with kind people instead of suspected criminals.

Their next stop was police headquarters, where George turned in the pistol and explained where it had come from. An officer dusted it for fingerprints while they waited, but unfortunately there were none except George's.

"It'll be difficult to trace the owner," the officer told them, "unless we can find a bullet fired from this gun." He thanked the young people for bringing the weapon in. Then they left.

"And now into the tub!" George said gleefully when they reached the Cosgrove home.

"After I take a shower," Nancy said, "I'll be ready for another bit of sleuthing. I'd like to see a submarine. Danny, do you think there might be one in port at the Key West Naval Base?"

"It's possible," he replied. "I don't know if they'll let you go aboard, though."

"We can try. If we tell them about the mysterious periscope at Crocodile Island, they might."

George chuckled. "Of course they will. How could anyone ever say no to Nancy Drew?"

CHAPTER XVI.

Exciting Phone Call.

AFTER the girls had bathed and changed into fresh clothes, they went into the living room and told their hosts about the adventure on the uninhabited island.

Mrs. Cosgrove was worried about the pistol, but Danny calmed his mother by telling her that they had already delivered it to the police.

Nancy said, "I'd like to learn more about submarines. Mr. Cosgrove, do you know someone at the naval base in Key West?"

He nodded. "As usual, you're lucky. It happens that Captain Townsend is an old friend of mine. I'll give you a letter of introduction and if he can spare the time, I'm sure he'll show you around and answer all your questions." He smiled at Nancy. "But don't ask him to tell you any of the secrets of the U.S. Navy!"

Nancy knew she was being teased because of her reputation as a girl sleuth. She smiled back and said, "Maybe I'll find out some secrets without being told!"