Nancy stood deep in thought for a few moments, then she took the pencil attached to the notebook and quickly began to erase the figures. One by one she moved the numbers around so that if they were a code, it certainly was scrambled now! She closed the notebook and laid it back on the ground.
As she did this, another idea came to her. Suppose the spy was the same person who had come to her house and either released or flown the robot copter! If she found the same type of soil on the rungs of the ladder as she had on the copter’s tires, it could be a clue. The young detective realized that two days or more had elapsed since the robot copter had taken off from a swampy, wooded area. During that lapse of time mud on shoes could have been scuffed off.
“Or the man might have been wearing different footwear today,” she thought.
“I’ll take a look, however, to be sure,” Nancy decided. “Anyway, since I don’t have a key to the house, I’ll have to climb the ladder to get back inside and lock all the windows.”
Slowly she mounted the rungs, examining each one thoroughly as she went. Every few seconds she would turn around to be sure the red-haired man had not returned and was about to pull her down with the ladder.
She reached the top safely and stared at the last rung. Evidently the stranger had balanced himself on his arches while he was sketching, and left sizable chunks of mud on the wood.
“It’s that same mud with the little bits of wood in it!” she said to herself.
Nancy quickly stepped into Ned’s bedroom and closed and locked the window. She now made sure that the other window in his room was fastened, then checked all the windows in the whole house.
She went back to Ned’s bedroom, turned the blackboard over, and tested herself on the eye-shaped set of numbers. She was glad she had remembered everything correctly. Nancy now erased the whole design and put the blackboard in the closet.
Just then the telephone rang and Nancy went to answer it. The caller was Bess.
“Where are you?” she asked. “We’re all getting worried about you.”
“Don’t worry any longer,” Nancy replied. “I’ll be over in a few minutes. There’s been a little excitement here, but everything is all right now. Bye. See you.”
Before leaving, Nancy stood in the living room and reflected on whether or not she had done everything she should.
“The ladder!” she thought. “I mustn’t leave that in place. I wonder where the man got it.”
The young detective decided to put it in the Nickersons’ basement. This accomplished, she called the police and suggested that they keep a watch on the house and nab the owner of the notebook if he returned.
Then Nancy climbed into her car and headed for the restaurant. During the drive her thoughts were on the mud she had seen across the top rung of the ladder.
“I must locate that mucky, swampy place. If Glenn Munson can take me on another flight, perhaps I can find it.”
Nancy finally arrived at Flannery’s restaurant, where the rest of her group was waiting to have dinner.
She sat down and then said, “I’m dreadfully sorry to be so late.”
George spoke up. “Don’t keep us in suspense. Tell us what held you up.”
As Nancy related what had happened at the house, the others grew more and more astonished.
At the end of her recital, Bess asked, “What did you do with the notebook after you changed the numbers?”
“I left it where I found it and notified the police.”
While they were eating, Nancy mentioned her plan of calling Glenn Munson and trying to find the swamp area where Ned might be a prisoner.
Mr. Nickerson had a suggestion. “I’m sure that the Emerson College library must have an excellent collection of books on the geology of this region. Perhaps you can find one that describes mud similar to what you found. In the meantime I’ll call the State Forest Commission and see what I can find out.”
When they reached home Nancy immediately went to see if the notebook was still there. It lay where Nancy had put it. A plainclothes policeman at once stepped from behind a tree and said no one had come for it.
“I’ll wait a little longer, then take the notebook with me,” he told Nancy. “I doubt that its owner will return.” Nancy was inclined to agree with him.
Despite her concern, Nancy slept soundly that night. Early the next morning she telephoned Glenn and arranged to take a trip with him the following morning at ten o’clock.
“Sorry I couldn’t make it today,” he said. “By the way I have some information for you. Evidently the mysterious copter had a phony registration number on it. The authorities haven’t been able to identify the owner of the craft. Wish I could have had better news for you. See you tomorrow.”
“I’ll be there promptly,” Nancy promised. “Thanks a lot.”
After breakfast the girls said good-by to Mr. and Mrs. Nickerson. There were a few seconds when each thought the others were going to cry, but they all braced themselves and wished the rest good luck in finding Ned.
“You’re doing very well, Nancy,” said Mr. Nickerson, “and I wish I could have picked up as many clues as you have.”
The young detective said she hoped they would lead somewhere. She and the other girls climbed into her car and took the same route as they had the day before.
Upon reaching Emerson College, Nancy left the cousins at the fraternity house and went on to the campus library alone. She had met the reference librarian several times, so she was admitted on her own identification.
When Nancy told her what book she wanted to consult, Miss Greenleaf directed her to the proper section. For an hour Nancy buried herself in the fascinating subject of geological findings of Emerson and the surrounding area.
Her search for swampy districts was finally rewarded. There were three in different locations outside Emerson.
“Here’s one that’s in a straight line from my home in River Heights,” she decided and read more about it.
Apparently the swamp was an unusual place. There was a hilltop in the center of a large circular area, which was wooded but mucky. The text said that it was impossible to drive through the swamp. The only way to explore it was either on horseback or on foot in high boots.
“But one must watch carefully for dangerous spots that seem to have no bottom,” she read. “There are many rotted logs, some of them under the slimy water.”
Nancy reread the paragraph. “It sounds like a good place to avoid,” she thought, but immediately decided nothing would keep her away if there was any chance of going in and rescuing Ned.
She returned to the fraternity house just as students were coming in for the lunch hour. Bess, George, Burt, and Dave met her.
“A letter for Burt Eddleton,” one of the students sang out.
Burt went to get it from the pile of recently delivered mail on the hall table. He looked at the envelope, then excitedly brought it to show to his friends.
“This is from Ned!” he whispered. “And here on the outside in another handwriting someone has written ‘Found on road near Arbutus.’ ”
“Where is Arbutus?” Bess asked.
No one could answer her question.
Dave said, “Open it.”
Quickly Burt slit the envelope and took out the enclosed note. In a hastily scrawled handwriting Ned had written, “Don’t know where I am. Prisoner of red-haired nut.”
At once there were conjectures about who the red-haired nut was. Could he be Crosson or perhaps someone else connected with a Cyclops gang?
Bess spoke up. “I still want to know where Arbutus is.”
Nancy’s trip to the college library suddenly paid off. “I remember now. It’s a small town fairly close to the swamp that I’ve decided to investigate.”
Dave asked how far it was from Emerson.
Nancy replied, “Not far. Let’s go to Arbutus in my car right after lunch. We can take it as close as possible to the swamp and then walk the rest of the way.”
&nbs
p; “The rest of the way to where?” Bess asked.
George spoke up. “The place where Ned may be a prisoner, silly!” she chided her cousin.
Burt stared at the girls’ feet. “I hope you brought hiking boots. You’ll need them to slosh through a swamp.”
Ruefully the girls said they had not packed any, but they would go anyway. Burt winked at Dave but said nothing. An hour later three pairs of men’s small-size hiking boots, borrowed from short students in the fraternity house, stood in the guest room.
As Burt drove the group toward Arbutus, they discussed the case again. George wondered how Ned’s note had got onto the road. She even suggested that it might have been planted there to lure Ned’s friends to a place where they might become prisoners.
“In that case, we’d better not go,” said Bess. “Nancy, what do you think?”
The young detective was inclined to believe that in some way Ned had managed to tuck the note in a crack on the outer wall of the mysterious copter.
“He hoped it would fall off while the whirlybird was in flight, and drop where somebody would find it.”
“I’ll bet you’re right,” said Dave.
They reached Arbutus, and obtained directions at a gas station to a road which led directly to the swampy area. The attendant looked at them strangely and finally warned the group that the place was dangerous. “People have been known to lose their lives in there.”
“We’ll watch our step,” Nancy assured him. Burt drove as far as he dared, then parked. They all got out and started off on foot. Even before they reached the woods, the path became almost impassable.
It would not have been possible to proceed in anything but hiking boots. The group was so busy watching the ground that there was no conversation.
Then suddenly Dave cried out, “Look! There goes a copter.”
It had risen from behind the hilltop ahead and now flew away. The hikers stopped short. The same thought ran through the minds of everyone. Was Ned aboard the helicopter?
CHAPTER XI
Wilderness Cabin
As the copter turned and flew off, George said, “Come on! Let’s follow that pilot!”
Bess looked at her cousin in amazement. “How would you do that?” she asked. “I didn’t bring my wings.”
The others laughed but Nancy’s eyes were focused on the direction the helicopter had taken. It was going in a westerly direction. Where would it land?
Burt spoke up. “Maybe that craft isn’t connected with your mystery case, Nancy.”
“You could be right,” she replied. “But the copter certainly looked like the one that landed on my front lawn. We never could follow it, though. Let’s go on to the swamp.”
They finally came to the edge of the mucky area and trudged up the hill, which, according to what Nancy had read, stood in the center of the swamp.
The incline was steep. Low-growing bushes and trees, partially withered, grew here and there on the hillside. A lot of shalelike rock made the climb hazardous.
Presently Bess stopped. “This is positively the worst hike I have ever taken.”
Her cousin George teased, “It’s going to be worse on the other side. Cheer up!”
When the group reached the top of the hill, they surveyed the landscape in front of them. The swamp below looked wider than the one through which they had just come.
When they reached it, the young people also found it was much more treacherous than the other one. They sloshed along in ankle-deep mud, then stopped to wash it off whenever they came to clear pools of water.
It was comparatively still in the wooded swamp, but suddenly a crow took off from the ground with a screech. It landed in a treetop and cawed raucously.
Nancy smiled. “I guess he’s warning the flock that there are intruders on his premises.”
Though the going was rough, the group did not think about the arduous hike. They became interested in the beauty of nature around them.
“Look over there!” said Dave. “A ringneck pheasant.”
The large iridescent bird with the white ring of feathers around its neck did not stir from the log on which it was standing, its long tail sweeping out behind.
“Listen!” George said a few minutes later.
The trekkers stopped and became silent.
“Hear that warbler?” George asked.
They could detect the dainty trilling notes of the warbler’s song but it took time for them to find the bird. Finally Bess saw it seated high on the branch of a tree. “There it is!”
Nancy remarked, “From here it looks like a bird without a head. If it weren’t for his eyes, you wouldn’t know he had one. He looks as if a black mask had been pulled down over the upper part of his head. I guess that’s why it is called the hooded warbler.”
“Did you know,” George asked, “that the female of this species doesn’t have a mask? I suppose that’s so she’ll surely be seen by the boy warblers.”
The group laughed and went on. Bess, intrigued by the wildlife, kept looking up. Without warning, she stepped into a deep hole of muddy, greenish water.
Instantly the others pulled her out, but she was a mess. Nancy took several tissues from her pocket and began to clean her friend’s legs.
“Ugh!” Bess said suddenly. “Look at these things crawling around on me!”
Dave said kindly, “They won’t hurt you. They’re only miniature salamanders.”
He tore leaves from several bushes and helped wipe off Bess’s dungarees and sweater, while George and Nancy worked on the girl’s hair.
“What am I going to do?” Bess wailed.
“Grin and bear it,” George replied. But she did admit feeling sorry for her cousin.
“I guess from here on I’d better watch my step more carefully,” Bess said finally. She was still shaking from her unexpected bath and held Dave’s hand tightly for the rest of their trip through the swamp.
Immediately ahead was a small, open field which everyone assumed must be the place from which the helicopter had taken off. Directly beyond was another swampy area. A small cabin painted dark green blended so well with the surrounding growth that it was hardly noticeable.
“That could be the place where Ned is being held!” Nancy said excitedly.
The three girls and their companions walked across the field and gingerly went forward. The ground was spongy, caking their boots with mud, but walking was not as difficult as it had been in the swamp.
No one said anything at first, then George commented, “That swamp sure was an obstacle course, and I don’t relish going back through it.”
“Nor I,” Bess said. “I hope somebody can figure out a different way of getting to the place where we left the car!”
Nobody answered her because all of them were sure they would have to return along the same route.
Nancy hurried in front of the group and walked up to the cabin door. She knocked. No one replied. She pounded loudly but in vain.
“Nobody home,” she said. “Unless someone’s hiding in there.”
Nancy added that it was possible Ned was a prisoner and could not make a sound. He must be rescued!
She tried the door and finding it unlocked, she walked in. Her friends followed. No one was in sight.
All gasped in astonishment. The one-room cabin was a fully equipped electronic laboratory with two cots, a small stove, and well-stocked shelves of canned food.
“Well, Sherlock Holmes,” said George to Nancy, “what are your thoughts now?”
Before replying, Nancy began to examine the laboratory. Burt and Dave did also. There were all sorts of gadgets, and open notebooks with numbers which meant nothing to the visitors.
Meanwhile, Bess had been looking around. She announced that there were no clothes in the place. “Do you suppose whoever lives here knew we were coming and skipped out?” she asked. “Otherwise why would anyone leave all this good food—meat, eggs, milk, and bread? I could eat some of it right now.”
 
; Presently Burt and Dave called to the girls to come to a corner of the lab.
“We’ve discovered a remote-control outfit, and here’s the sending set.”
“And over there,” Dave added, “are a computer and programming tapes.”
“Are you saying,” George spoke up, “that the robot copter was kept here and its movements were controlled from this cabin?”
“It looks that way.”
Bess asked, “Do you think Ned, Crosson, and the red-haired nut were in the copter we saw flying away from here?”
“I have a strong feeling,” Nancy said, “that Crosson and the red-haired nut are one and the same person. I believe that Ned in his note was trying to tell us that Crosson is crazy and dangerous.”
Dave reminded the others that they were just doing a lot of guessing. “We haven’t come across one single thing around here to prove who the occupants are.”
Nancy agreed with Dave and said that it was important they try to find out. “Let’s all hunt for a clue,” she proposed.
Everyone went to work. There was complete silence for a long time.
Nancy looked under both cots and pulled them from the wall. Suddenly her eyes fastened upon a mark which had been cut into the wood of the wall. At first glance it seemed to be a W. Was it someone’s initial?
She called her friends’ attention to it and they came over to look at the initial. Nancy squinted her eyes and stared at it.
Suddenly she said, “This isn’t a W. I’m sure it’s two N’s. And that could stand for Ned Nickerson!”
Bess, George, and the boys leaned over to examine the mark. They all agreed that indeed it was NN.
“This is where Ned must have slept,” Burt said. “And I’m convinced he was taken away in the copter we saw leaving here.”
“Do any of you think he’ll be brought back?” Dave spoke up. “I don’t.”
No one did, but Burt and Dave were inclined to think that Ned’s captor might return. They were of the opinion that he would not leave the valuable equipment unguarded for long, although the possibility of it being taken in this forsaken place was slim.
Nancy was quiet for several minutes while the rest searched some more. When they reported that there were no other clues, she told the group that a possibility of getting to the main road without hiking there had just occurred to her.