CHAPTER XVIII

--THE TOY BALLOONS

"There's another one--that makes six."

"Six what, Ben?"

"Balloons."

Tom walked to the window where Ben had been sitting, looked at the sky, made out a tiny blue dot sailing aerially seawards, and observed:

"Oh, you mean toy balloons?"

"Yes. There must be a picnic somewhere. Funny thing, too. I noticed they all had a card or a tag attached to the trailing strings."

"Perhaps it is some advertising stunt," suggested Tom.

He resumed the reading of a technical wireless book he had received from New York, while Ben continued idly looking from the tower window.

Affairs at Station Z had settled down to routine. They had learned no results as yet from the mysterious appearance of Bill Barber at the tower the evening before. Suddenly Ben broke out with the words:

"There comes Bill Barber, now."

Tom awaited the appearance of the former captain of the Black Caps with some curiosity. He pointed to a chair as the Barber boy came up through the trap door.

"What's the news, Bill?" inquired Tom casually.

Bill's broad mouth expanded Into a grin. He chuckled serenely.

"Haven't heard anything about last night?"

"Not a word."

"You will if you go down Fernwood way."

"Indeed?"

"Yes, there's two fellows keeping themselves mighty scarce. When they walk they wobble, and when they talk they squabble."

"Do I happen to know the parties?" inquired Tom, but already guessing their identity.

"I reckon you do," answered Bill. "Making no bones about it, the fellows are Mart Walters and Bert Aldrich."

"I thought so," put in Ben. "They were up to tricks, were they?"

"They were up to queering you fellows," replied Bill, "and I learned of it. I knew yesterday they were coming down here after dark to wreck your wireless plant. I owed that cad, Aldrich, something, and I reckoned to pay off two scores at one and the same time. I lay in wait."

"And they showed up?" inquired the interested Ben.

"Yes, about nine o'clock. They tried to get up through the trap door, me watching them. They couldn't make it, and then they went down to the beach and got an armful of big flat stones. Aldrich was to go up that tree yonder and Mart was to pass up the stones to him. He calculated to throw through the tower windows and smash your outfit."

"I see you didn't let them, Bill," suggested Tom.

"Not I. Both barrels of the shotgun were loaded to the muzzle with pepper and salt. Just as they got under the tree I let both triggers go. It took them around the knees."

"I hope you didn't cripple them," said Tom.

"Oh, they could walk," replied Bill with a guffaw,--"just walk. I understand that Aldrich has thrown up his hands and is going to call the game closed."

"What do you mean?"

"He's going back to Boston some time between now and to-morrow night. I guess Miss Morgan has turned the cold shoulder on him. Well, he's a good one if he gets away with the eleven dollars and seventy-five cents he owes me for work on the yacht, and good hard work at that."

Bill Barber hung around for about an hour. He seemed to be glad of an excuse to visit the tower. He was mightily interested in the wireless outfit, and he seemed pleased to be in Tom's company.

"Bill is not so bad a fellow after all," remarked Ben, as their visitor departed. "What a shame! that Aldrich, with all the money he brags about, cheating him out of his honest wages."

"I think Bill is likely to get it," said Tom. "He is a determined and a dangerous fellow, too, when he is once aroused."

"I can see that," replied Ben.

"He has proven himself a good friend to us," observed Tom.

"Grace Morgan doesn't seem to have much use for Aldrich. I suppose he'll try to break in and bid her good-by. I hear she is going away for a month or two."

"She has gone already," said Tom, with a conscious flush.

"Oh, is that so?"

"Yes, she left for Albion this morning, where her aunt resides. They take the steamer _Olivia_ this evening down the coast. They are going to a Virginia Summer resort."

"You seem pretty well informed as to Miss Morgan's movements," observed Ben with a wink.

"Why, yes, I saw her last evening," replied Tom. "We are very good friends, you know, and I am naturally interested in her plans."

Tom did not tell his chum that in his breast pocket reposed a dainty little card bearing the southern address of Grace, nor that she had made him promise to write her often about the progress he made with "that delightful wireless."

"I say, there is another one of those balloons," exclaimed Ben suddenly; "a red one this time. She's lighting. No, she isn't. Yes, she is, but in the water. Tom, I'm curious about the tags all of those balloons seem to have attached to them; I'm going to make a try to get one."

Ben bolted from the tower. Tom went to the window to watch his manoeuvres. Ben reached the shingly beach, and was reaching out into the water with a long tree branch, trying to hook in the now exhausted balloon without getting his feet wet.

"He's got it," tallied Tom, keeping track of his movements. "Well," he inquired a minute later, as Ben reappeared in the tower, "what does it amount to?"

"There has been some pencilled writing on the back of the tag," explained Ben, "but the water has blurred it out."

"Whose tag is it?"

"Tom," said Ben, "what do you think? It's one of your own cards!"

"Mine?" exclaimed Tom in surprise.

"Yes--look at it."

Tom took the soaked piece of cardboard. He regarded it in some wonder.

"Why, Ben," he said finally, "you are quite right. This is one of the cards I printed when I went into the amateur printing line last Summer."

"I knew I'd seen it or its like before," observed Ben.

"It's strange," ruminated Tom, turning the card over and over in his hand in a puzzled way. "Say, though," he cried with a quick start, "I gave a lot of those cards to Harry Ashley."

"When?" asked Ben.

"Last week. I was cleaning up my desk at the house, and threw away about two hundred of them as useless into the waste basket. Harry picked them up and asked for them."

"And you gave them to him?"

"That's it. He said one side was blank, and he liked to carry something with him he could scribble on when he took the fancy."

"Why, then," declared Ben, getting very much excited, "that card comes from Harry!"

"It looks that way," admitted Tom.

"Of course that is it," insisted Ben. "It's Harry who has been sending up those balloons."

"But how could he do that?"

"There's the mystery, like all the mysteries we've been running across lately," said Ben. "Don't you see, Tom, he had some writing on the back of those cards?"

"It's all washed out now."

"Yes, I see it is. See here, he is in trouble somewhere, and trying to send us word. Don't you think we had better get out and try and find some balloon that has dropped on land, or chase one and run it down?"

"Well, that might be a good way," replied Tom slowly, as though he was thinking deeply on some matter. "But perhaps we can do it easier."

"How?"

"By trying to decipher the writing on this card."

"But you can't!" exclaimed Ben half impatiently, as he held up the dripping pasteboard. "You can't read it. Try for yourself. Might as well try to read in the dark."

"I know you can't read it now," assented Tom, "for the water has about soaked off the black marks of the pencil. But there may be a way of bringing back the writing."

"How? Do you think Harry used some kind of invisible ink? I've read of prisoners sending secret messages to their friends written with some chemical that would not show unless it was heated, or something like that. Say!" he cried with sudden interest, "do you mean that way, Tom?"

"Well, no, not exactly. Harry didn't use ink. He used a common lead pencil, from all appearances, and the water has soaked the black marks off. But you know when you use a pencil on paper, it always makes little depressions in the surface, corresponding to the shape of the letters. Did you ever put a piece of paper on top of another piece, and write on the top sheet?"

"Of course I have."

"Then you've probably noticed that on the second sheet there would be marks by which the writing could be read, even though the black pencil characters did not show."

"Of course. I see what you mean."

"I thought you would. I mean to dry out this card, and then, in a good light, we ought to be able to tell what the marks are. In that way we can decipher what Harry wrote even though the black marks are gone."

"Good! Let's do it. That's easier than chasing after a balloon. Here, I'll dry the card."

He reached for it, and approached the window on the sill of which the sun just then shone brightly.

"That's it!" cried Tom. "Meanwhile I'll get out a magnifying glass to use on the card when it's dry. With that we ought to be able to read what it says, even if the impressions are very faint."

"Say, there's class to us all right," observed Ben with a laugh. "Maybe we can get a job somewhere, reading secret messages for the government. That would be excitement, and----"

"Here's some new excitement," announced Tom, with a glance from the window.

"Wonder what's up now?" speculated Ben, as he too took a look. "It's Bill Barber come back, and he's making for here on the run."

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