"Funny I never saw it go through town," Reilly remarked at this point.

"But what you don't know can't set the river on fire." He grinned.

"It's more than that," Terry agreed. "That woman didn't seem to want to be seen in town at all."

"And something very queer about the whole thing," Sim interrupted, "is where has Melissa been all this while? She usually hangs around our house."

"Oh, I wouldn't consider that," Reilly suggested. "This bad weather probably accounts for it. She's home."

"Well, then, after that," Arden went on with her story of events, "a man, dark, tall, and somewhat like Dimitri, drove up one night and he, too, asked the way to the _Merry Jane_. He wouldn't let us row him over. He was very polite about it, and he took our boat. Toward morning I saw him drive away in his car that he had left parked at Terry's house, and-and-"

Arden faltered as she realized another surprising fact-"that's the last time we heard from Dimitri!"

CHAPTER XIX Tania Howls

This startling announcement held them all speechless. They had completely overlooked its significance. And yet it was so obvious. The dark stranger had evidently come over to the houseboat that night and-- Surely he was responsible for Dimitri's disappearance.

Terry wandered over to the combination bed and couch and sank down upon it. She looked in a bewildered fashion at the floor and almost immediately was galvanized into action. At her feet lay a white paper; something they had not noticed before. She s.n.a.t.c.hed it up and spread it out on her knee. It was part of an envelope torn partly across and lengthwise. Written on it in ordinary blue ink was this:

_Ser_ _Ninth S_ _New Y_

"Look!" excitedly exclaimed Terry. "Here's part of an address!"

They all crowded close to see, and Chief Reilly, as befitted one in his station, held out his hand for the paper. Terry meekly gave it to him.

"You're right!" he exclaimed and turned the paper over. Then, as the surprised girls watched, he drew out from the inside of the envelope a second small piece of paper. "This seems to be some kind of a map," he announced, turning it around in an effort to decide which was the top.

"Let's see!" Arden asked. The chief gave it to her. "It is a map!" she agreed, "and it shows the road from the city and the branch one to the village. See, it has part of the word Oceanedge."

"Perhaps we can find the rest of it," Sim suggested. But a most careful search failed to reveal more of the paper.

"Olga dropped that!" Arden announced suddenly. "I remember seeing it fall from her bag, but I was too stupid to do anything about it."

"Oh, no, Arden," Terry said. "If you had noticed it and called it to her attention, she would have picked it up again. As it is now, we're reasonably sure she knew the way to the _Merry Jane_ all the while, though she tried to make us believe she didn't."

"And to think we let her go without even finding out her name or who she was," Sim moaned.

"Now I'm sure there's something queer about Dimitri being away," Arden said convincingly. "Why should Olga pretend to be ignorant about the road? Why didn't she worry about Dimitri? How did she know about the snuffbox? She went straight to the cupboard as if to get it."

"You girls may have stumbled on something at that!" the chief exclaimed with a faint note of admiration in his voice. "Yes, indeed!"

They stood in the untidy living room wondering what might be the solution to all this mystery. Tania rubbed against Sim's slim legs. The girl gently pulled the silky ears, something forming in her mind.

"I've got an idea!" Sim cried out. "Perhaps Tania could trace Dimitri if she had something of his to sniff at. After all, she's a wolfhound, and the hound part of her name must mean that she can trace missing persons."

"We can try," Arden admitted. Somehow, despite the chief's presence, the girls regarded the "case" as their own and did not dream of consulting him on matters such as this one.

Momentarily the discovery of the piece of letter and the map was forgotten in the excitement of the new suggestion. Sim found a battered old felt hat and held it before Tania's nose.

The dog sniffed at it disdainfully and then sat back on her haunches looking at Sim.

"Go find him!" Sim urged. "Find Dimitri!"

The tone of her voice may have done it, or else it was a game of dog and played before, for she sprang up again and dashed toward the door.

Standing on her hind legs and pushing with her forepaws, she opened it, for it was not fully latched.

Tania galloped down to the water edge and ran back and forth excitedly, her nose to the ground. The cat-tails in the marsh bent before the strong wind, which whistled eerily through the tall sedge gra.s.s. As is usual with nor'easters, the rain had temporarily ceased again, and the afternoon sky seemed a little brighter. Tania turned to look questioningly at the girls as she raced back and forth along the little strip of ground. At last she stopped and, sitting down, facing the storm-swept bay, she howled mournfully.

"Tania!" Arden called. The dog came slowly to her, tail between her legs, a picture of despair.

"What does that mean?" Terry asked of Reilly. She did not dare to interpret the performance for herself. "Do you think he may have-drowned?"

"Naw," Rufus Reilly replied scornfully. "It probably don't mean a thing.

That dog couldn't follow no scent in the wet weather. Just the same," he continued wisely, "this here is a mysterious case, all right, all right!

I'm glad you called me in. It's the first time I've had any real work to do in years. Now, what in thunder did I do with that paper? I've got to study it a bit." He began to search in his numerous pockets.

"Here it is, Mr. Reilly," Arden said handing it to him. "You let me look at it."

"Oh, yes, so I did! Well, I guess there's not much we can do around here, is there?" he asked the girls. "Out of sight makes the mare go." Another, of his silly, joking proverbs.

They shook their heads silently. Arden took Tania back to the houseboat again and shut her inside. Food and water had been left for her. Then, after a quick look around, they all left.

"I'll work on the case," Rufus Reilly announced as he climbed into his car, "and let you know about it sometime tomorrow. Don't worry, though.

It'll all come out in the wash." And chuckling at his poor joke he drove away in the early twilight.

CHAPTER XX Mrs. Landry Helps

"Great help _he_ is," Sim remarked disdainfully as they watched the old car b.u.mp along.

"We don't know any more now than we did before," Terry said, agreeing with Sim.

"Yes, we do," Arden contradicted. "You're forgetting about that paper.

While you two were watching Tania perform her little trick, I was memorizing the words on that torn piece."

"Good for you, Sherlock!" Sim exclaimed. "And what do we do next? Go home and work out the cryptogram?"

"Something like that," Arden answered. "I've got a plan. Let's get going, and we'll see how it works out. Terry, is it too late to go to town for just a few minutes? What I'm going to do won't take long."

"What are you going to do?" Terry questioned. "Tell us."

"I thought of going to the drug store and trying to trace the writer of this note by getting information of the New York telephone company,"

Arden told them.