it was nearly nine o’clock when they returned from a long sail on the lake and, declining an invitation to sit on the porch of the sleeper’s cabin on the ground that they might miss something if they stayed away from their cabin any longer, the boys bade them good night and turned off toward their quarters.

“give a yell if anything happens,” mr. sleeper called when they were about half way to the door. “i’m going to sit up, you know, and if there are any demonstrations i should like to be present.”

“do you know, jack,” bob began a little later, looking up from the book he was reading, “i can’t for the life of me understand how it is that nothing has been seen or heard in the other cabin.”

“are you sure there hasn’t?”

“of course we’ve only their word for it.”

“of course.”

“but why should they lie about it?”

“i haven’t said they had lied.”

“but you implied it.”

“maybe.”

“look here, son, do you suspect that they know anything about it?”

“who was that detective that used to say ‘suspect everyone and everything’? no, frankly i don’t. we came here first and the ghost was busy long before that so how could they be mixed up in it?”

“of course that’s a point in their favor, but after all it doesn’t prove anything. one or all of them, for that matter might have been around here somewhere without actually stopping at the camp.”

“that’s true too. but really you know we have no real reason to suspect them. they certainly are refined people and why should they be up here for any such purpose as that? if it wasn’t for two or three litle things, about which we have spoken, i’d never have given a thought to them in that connection.”

“i know what you mean and i feel the same way.”

“one thing is pretty sure and that is that if they are mixed up in it they are not the ones who are actually doing it. they couldn’t have shot that arrow the other day you know.”

“and that’s another point in their favor.”

“well, i guess we’ll have to return a verdict of not—what was that?”

a loud thud on the door interrupted him and, even as he asked the question, jack was on his way toward the door. it was dark outside as there was no moon but the light of the lamp shone out and enabled him to see for a distance of several feet. there was no one in sight and, after a hasty glance around, he was about to turn back when his eye caught sight of an arrow deeply imbedded in the pine door. it took a strong pull to draw it out, but in a moment he had it inside and was showing it to bob who, instead of following him to the door had hastened to the window beneath which he had set the trap.

“another warning, i suppose,” he said with a slight grin as he pointed to a bit of paper which was tied with a bit of string about the middle of the arrow.

jack had it off in a jiffy and together they bent over it. there were but two words printed in large letters, “last warning.”

“the plot thickens,” bob whispered and jack was sure that he detected a note of uneasiness in his brother’s voice.

“three strikes and out, eh?”

“not out,” bob snapped. “in the words of the immortal perry, ‘we’ve only just begun to fight’.”

“if only we could get hold of something to fight. ghosts are mighty elusive things, i’ll tell the world,” jack declared.

“but, judging from that note, we’re about due to find something,” bob reminded him.

“how about calling mr. sleeper?”

“not yet. let’s wait and see if anything more happens. we can show him the arrow and note just as well in the morning.”

for an hour they sat, one on each side of the table, and read without speaking. then, just as the clock, over in the dining cabin, struck eleven jack closed his book.

“time to put out the light,” he said.

bob also closed this book and turned the light so low that practically no light came from it.

“if we hear anything,” he said, “i’m going to hide right below that window sill and if you see that thing i want you to give a low whistle. somehow or other i have a hunch that he or it’ll be too sharp to walk into that trap and i’m going to make a grab for it.”

he had hardly finished when the spot of light appeared on the wall and he at once did as he had said. the window sill was only about two feet from the floor and his position, as he crouched there, ready to spring was anything but comfortable. he was obliged to move slightly from time to time to keep his muscles from cramping, but he was careful to make no noise.

for what seemed a long time but was in reality only a few minutes he waited and then the signal came. instantly he jerked himself up and, without waiting for even a glance, thrust both hands through the cotton mosquito netting. they closed on something hard and, with a quick yank, he pulled it in through the window.

“turn up the light, jack,” he shouted.

jack quickly obeyed the order and, as the light flooded the room the two boys gazed at the object which bob held in his hands. for a moment neither spoke then jack gave vent to low chuckle.

“some ghost,” he laughed.

it was little wonder that the boy laughed for the object which bob was holding in his hands was a pumpkin painted white and mounted on the end of a broom handle. grotesque features had been cut through the rind and the inside had been hollowed out and a candle fitted to the end of the pole. a white sheet was draped on the lower part of the pumpkin and flowed down nearly to the lower end of the pole.

“did anybody have hold of it?” jack asked.

“must have. it took a good yank to get it away.”

“but did you hear anything?”

“narry a sound.”

“where do you suppose they got hold of a pumpkin at this time of year? must be a last year’s one.”

“of course.”

“well, what—”

but the question was left unfinished for at that instant a loud shriek rang out through the night. for an instant the two boys looked at each other without speaking, then they heard mr. sleeper calling.

“bob, jack. here quick!”

they rushed out of the cabin together and met mr. sleeper half way between the two buildings.

“did you hear that yell?” he gasped.

“of course. what was it?” bob said quickly.

“i—i’m not sure but i’m afraid it was helen.”

“helen!”

both boys uttered the name at the same time.

“it sounded like her voice and she’s gone.”

“gone? where?”

“i—i wish i knew. you see, she stepped out on the porch just a minute ago and then i heard that yell. i rushed out as quickly as i could but she wasn’t there.”

just then jacques joined them.

“what dat yell?” he demanded.

“that’s what we all want to know,” bob told him. “mr. sleeper thinks it was helen.”

“where ees she?”

“she’s gone,” mr. sleeper groaned just as a voice called from the cabin.

“where’s helen?”

mrs. sleeper appeared, coming down the path, a bath robe thrown hastily about her. her husband caught her in his arms and hastily explained what had happened, trying to make as light of it as possible. but she was not deceived and sobbed heavily as he led her back to the cabin, the others following.

“what can we do?” mr. sleeper asked a moment later.

“go after them, of course,” jack said eagerly.

“they can’t be far away and if mrs. sleeper isn’t afraid to stay here alone i suggest that you and jacques go one way while jack and i go another,” bob suggested.

“go by all means.” mrs. sleeper sobbed. “and don’t come back without her. i couldn’t bear that.”

“i’ll get our flashes,” jack said.

he was back almost immediately and mr. sleeper brought out two flash lights handing one to jacques.

“we’ll go down the lake while you go up,” bob proposed. “but we don’t want to overlook anything. look for a trail and if you find it give a yell and we’ll do the same.”

“probably her father couldn’t follow an elephant track, but jacques ought to be able to recognize a trail if he finds one,” bob said as soon as they were out of hearing of the others.

“it’s like hunting for a needle in a hay stack in this darkness, but take it from me, we’re going to find that girl,” jack declared.

“you said it, son,” bob replied grimly.

putting into use every bit of the training they had received from long years spent in the woods they made their way, as rapidly as they deemed prudent, through the black forest.

“perhaps they took her in a canoe,” jack suggested.

“maybe, but if they did it would be useless to try to follow them on the lake in the night. water leaves no trail, you know. no. i’ve a hunch that they didn’t have a boat and that they went this way.”

“well, i hope your hunch is right,” jack declared as he stubbed his toe on a root and fell headlong.

for an hour they pushed on. they were not going in a straight line, but were zig-zagging in the hope that they would cross the trail of the man or men who had stolen the girl, but, as time passed and they found not the slightest clue, a feeling of discouragement took possession of them.

“i’m afraid it’s no use,” bob panted as he stopped to rest. “either they didn’t come this way or else they were clever enough not to leave a trail.”

“i think your first guess is right,” jack declared. “i don’t see how anyone could get through this thick woods in the dark without leaving some sign.”

“shall we turn back?”

“after what she said?”

“i know, but—”

“no buts about it. let’s keep at it. it’s the only thing to do.”

“all right, come on.”

they had gone but a few feet when jack’s keen eyes caught sight of something white caught on an old stump. with a low cry he snatched it up and held it out to bob.

“it’s hers,” he declared.

“are you sure?” bob asked looking closely at the small handkerchief.

“of course i am. look at that s in the corner.”

“i guess there’s no doubt about it. now let’s see if we can’t find the trail.”

for some minutes, by the light of the flashes, they searched. a broken twig, a single imprint of a foot or an abrasion of the bark of a tree would be enough to give them the direction. and finally, a few feet away from the place where he had found the handkerchief, jack hit it.

“here we are, bob,” he cried, “see that broken twig?”

it is one thing to find a hidden trail in the dense woods when one does not know where to look, but it is not nearly so difficult for one versed in the art to follow the trail once it is located. from now on they had little trouble in keeping on the scent.

“we promised to yell if we found it,” jack reminded bob a moment later.

“i know, but it would be the wrong thing to do now. in the first place they wouldn’t hear us and then we may be nearer the villains than we think.”

so they pushed on, now making fairly rapid headway and then having to hunt for some time before being sure which way the trail led.

“i’ve lost all sense of direction,” jack said, after they had searched for several minutes, about a half hour after striking the trail, “but it doesn’t seem to me that we’re heading for mount katahdin. how about it?”

“i haven’t been paying much attention to that myself, but i think we’re a long way off the mountain trail. unless i’m mistaken we’ve been heading toward millinockett lake for some time.”

“but what do you suppose—hark, did you hear that?”

“no, i heard nothing.”

“well, i did. listen.”

both boys strained their ears and a moment later a faint but unmistakable sound was heard.

“it’s a girl crying,” jack declared.

“and only a little way ahead of us,” bob added. “come on but be careful, it may be a trap.”

they had been using their flash lights freely as it was necessary in order to make any kind of time through the dense forest, but now they groped their way between the trees in the pitch darkness fearing to show a light. that they were pitted against a ruthless and keen enemy they did not doubt and they had no intention of playing into his hands if they could avoid it. as they advanced the sobbing became more clearly audible and they knew that they were going in the right direction. that it was helen they had little doubt and both longed to call out that they were coming, but prudence forebade it.

not a sound did they make as they crept closer to the girl, testing every step before making the advance. it was so dark that they were unable to see even a foot ahead and they were obliged to keep hold of hands to avoid being separated. as soon as the sound of the sobbing assured them that they were within a few feet of the girl they stopped and, for several moments, listened intently.

not a breath of air stirred the branches overhead and a death-like stillness pervaded the forest, broken only by the low sobs of the girl.

“if there’s anyone with her they’re keeping mighty still,” bob whispered placing his mouth close to jack’s ear.

“i don’t believe there’s anyone there but her.”

“nor do i but we must be sure. you wait here a minute and i’ll get a bit closer.”

jack was going to protest, but bob crept off before he had time to say a word and there was nothing for him to do but wait. he knew his brother’s ability to take care of himself but, as he afterward confessed, his heart was in his mouth.

noiselessly as a shadow bob crept on his hands and knees foot by foot decreasing the distance between himself and the girl. not a twig rustled nor did a stick move beneath him as he advanced. at last he knew that he could reach out his hand and touch her as he could plainly hear her deep breathing between the sobs which had now nearly ceased.

“helen,” he whispered.

a slight movement told him that she had heard him, but she made no reply.

“helen, it’s bob,” he whispered again.

“bob!”

the reply was low but the tone indicated her joy.

“is anyone here with you?”

“i—i don’t know, but i don’t think so.”

“take hold of my hand and try not to make a sound,” he whispered as he reached out his hand in the darkness.

as he found her hand he backed slowly away drawing her after him. no doubt she made as little noise as possible, but she was totally unskilled in the art of moving noiselessly through the darkness and to bob it seemed as though she made noise enough to be heard a mile. but nothing happened and foot by foot they won their way back to where jack was waiting.

of course the latter knew that they were coming as he knew that bob alone would not make the noise he could plainly hear.

“come on, jack, let’s beat it,” bob said as soon as he was near enough to whisper.

for perhaps fifteen minutes they crept through the woods the boys noiselessly and the girl making no more than she could help.

“now i reckon we can stop a bit,” bob said after he knew that they had covered several rods. “now, helen, suppose you tell us about it.”

“but don’t speak above a whisper,” jack cautioned her.

“i came out on the porch and someone grabbed me,” she began. “i gave a yell and then a hand was pressed over my mouth and i couldn’t make a sound. then he picked me up and ran and—and i guess that’s about all,” she finished.

“did he carry you all this way?” bob asked.

“every step. he must be a giant for he handled me as if i weighed about ten pounds.

“and there was only the one?”

“that’s all.”

“but what became of him?” jack asked.

“well, a little while ago we saw a light through the trees. i guess it must have been your light, and he began to hurry faster. i didn’t dare make a sound because he had told me that he would kill me if i did. then he fell and i guess he must have hurt his ankle because he swore fearfully. he picked me up again and started off but he limped a good deal, and—and pretty soon he threw me down and, without saying a word, started off alone. that’s all i know. but, tell me, how did you find me?”

“i—i guess god must have led us to you,” bob said slowly. “i don’t know how else we picked up the trail.”

“he must have. i knew that you’d try and i asked him to show you the way.”

“i guess we’ve been quiet all for nothing,” jack said aloud.

“maybe. but it’s better to be careful than sorry, you know,” bob told him.

“how far are we from the cabin?” helen asked.

“pretty hard to say,” bob replied, “but it must be all of five miles, maybe more.”

“where’s father?”

“he and jacques went the other way,” jack told her. “you see, we had no way of knowing which way you had gone so we divided forces.”

“can you find the way back?”

“i’m not so sure about that,” bob answered.

“then—then you think we’re lost?”

“don’t you fret about that,” jack hastened to reassure her. “we can find the way all right as soon as it gets light.” he meant that he might not be able to do it in the dark.

“oh.” it was evident that she was much relieved.

“it’ll be light in about three hours,” bob told them. “now, had we better camp here or try to find it in the dark?”

“i’m lost,” jack confessed. “haven’t the least idea which way home is. how about you?”

“well, it’s pretty hard to get much idea of direction when you can’t see your hand before your face, but i believe we can follow our trail back provided we can pick it up.”

“i didn’t think of that.”

“you and helen wait here and i’ll look about a bit and see if i can find it,” and before either could say a word he was gone.

bob was back in less than ten minutes with the cheering news that he had found the trail and that it was only a little way off.

“we’ll take it easy and be sure and not lose it,” he said as he took hold of helen’s hand and led the way, jack bringing up the rear clinging fast to her other hand.

“here’s where we found your handkerchief,” bob told her an hour later as he came to a halt and flashed his light on the stump.

“yes, i managed to get it out and drop it without him knowing it in hopes you might find it.”

“it’s mighty lucky you did,” bob said. “i’m afraid we would never have picked up your trail if you hadn’t. that fellow must be an artist in going through the woods without leaving a mark.”

“he did seem to be pretty careful. he had a flashlight and kept it on all the time until he saw yours. then he snapped it off and i guess that’s why he fell.”

“it’s funny we didn’t see his light,” jack said to bob.

“it does seem rather strange,” he agreed.

they rested a few minutes longer and then started off again. they had little trouble in following the back trail as they had made no effort at concealment and signs of their passing were plenty.

dawn was just breaking in the east as they reached the camp. helen gave a loud call as they emerged from the woods and almost instantly her mother was flying down the path to meet her.

“my darling child,” she sobbed as she gathered the girl in her arms.

helen quickly told the story and mrs. sleeper was most generous in her praise of the two boys.

“where’s dad?” helen asked as they reached the porch.

“he hasn’t come back yet.”

“oh, that’s too bad,” helen declared. “he must be worried half to death out there in the woods.”

“i suppose so,” her mother sighed. “but he’s got jacques with him and they’ll probably be back before long. but i’ve had enough of ghosts at last,” she declared turning to bob. “i never thought i could be so frightened.”

“what was it?” he asked eagerly.

“i’m sure i don’t know. it began about an hour after you left. first i heard a noise over toward your cabin and came out on the porch to see if i could see what it was. your place was all lit up and, through the windows, i could see something all white moving about and every minute or two there would be a noise as though someone was pounding on a tin wash dish. then off to the right, in the woods there, a bright light would flare up and then die down, and once i saw a white thing run, or rather float, along the path between your cabin and the dining-hall. it looked about ten feet tall but i don’t suppose it was. anyway, when it got to the door, it seemed to pass right through it without bothering to open it. and then—”

“yes?” bob encouraged as she paused.

“then after a few minutes it came out again and floated back to your cabin and the noises began again.”

“poor mother. it’s a wonder you didn’t die of fright,” helen declared.

“well, i didn’t, but i was scared.”

“and no wonder,” jack said.

“how long did it keep up?” bob asked.

“it must have been all of three hours.”

“was there anything else?”

“i—i don’t think so. after i saw the thing go back into your cabin i went inside and locked the door, but i could still hear the noise.”

“just imagine it,” helen sighed.

at that moment a loud whistle was heard and almost immediately mr. sleeper and jacques emerged from the forest. the former came slowly toward the cabin dragging one foot after the other, his head bent on his chest as though he feared to meet his wife and tell her that they had failed. but his entire aspect changed as he heard helen’s cry of welcome and assurance.

“thank god!” he cried as he hugged her to his heart.

the story, of course, had to be told all over again and at it’s conclusion jacques said:

“me have breakfus een two tree minutes.”

the boys, saying that they would go and wash up, turned toward their cabin and the others went inside. it must be confessed that bob threw open the door of the cabin with a distinct feeling of fear in his heart. was the mid-night prowler concealed there ready to jump out at them? that was the question he had been asking himself for the past few minutes. but there was no sign of fear in his action as he pushed the door open and stepped inside. though they had said nothing on the way over from the other cabin they both more than half expected to find the place in a condition of chaos. but everything was exactly as they had left it. not a single sign of anyone having been there could they find although they made a most thorough search.

“all quiet along the potomac,” bob grinned as he straightened up after looking under his bed.

“seems that way.”

“that ghost must have been a very orderly sort,” bob remarked drily.

“just what i was thinking,” jack agreed.

for a moment they stood and looked at each other.

“out with it,” jack finally said.

“what do you mean?”

“i mean that you are thinking that she was lying.”

“but why should she?” bob asked not denying the accusation.

“ask me something easy,” jack retorted.

“confound it, just as we make up our minds that they know nothing at all about it, something happens to throw suspicion on them.”

“my sentiments to a dot.”

“but that job tonight wasn’t a part of their game, that is, if they are mixed up in it.” bob insisted. “they may be good actors for all i know but that wasn’t faked. not one little bit.”

“again i agree with you. but, tell me this: just what makes you think she was not telling the truth? it would be possible for someone to come in here and prance around without disturbing things, you know. there isn’t so much to get out of place.”

“it isn’t that so much,” bob said slowly. “but just think, now. we find her all worked up over something she saw and heard in this cabin. she’s deeply grateful to us for finding helen and yet, she lets us come over here and come in without a word. now wouldn’t you have thought that she would have insisted on having jacques and her husband come with us?”

“of course i’d thought of that too, but perhaps in the excitement, she didn’t think of it.”

“maybe that’s it but all the same i’m more inclined to think that they know something, than i’ve been at any time before.”

“it seems to be a mystery within a mystery all right,” jack declared.

“another thing that worries me is about those traps. how could a body get up to that window and hold up that thing as he did without stepping on that trap unless he knew it was there? of course, it would be easy enough if he did know it but if he didn’t i can’t understand it.”

“and they and jacques are the only ones except ourselves who do know about them.”

“exactly.”

“but you mustn’t overlook the possibility that whoever it is that’s cutting up these didos might have been watching when we set them.”

“that’s true too, but i don’t believe it.”

“neither do i, but it’s not impossible.”

“well, there’s but one thing to do,” bob declared after a long pause.

“what’s that?”

“go and get sicum.”

“just the thing,” jack cried slapping bob on the back. “why didn’t we think of it before?”

“i did, but to tell the truth, i kinder hated to give up beat.”

“beat nothing. that’ll be simply bringing up reinforcements,” jack laughed.

before they could discuss the new plan further the breakfast horn sounded and they hastened to the dining-room. during the meal, bob, much to jack’s surprise, told the sleepers of their intention to go for the dog, sicum, which, he explained, belonged to their old indian friend, kernertok.

“sicum’s a wonderful dog,” he told them.

“but what will you do with him here?” mr. sleeper asked.

“track down that ghost,” bob said. “he may not leave any tracks which we can follow, but i’ll bet sicum can pick them up all right.”

“if he can’t nothing can,” jack added.