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The Radio Boys Series
(Trademark Registered)

THE RADIO BOYS TRAILING A VOICE

Or

Solving a Wireless Mystery

by

ALLEN CHAPMAN

Author of
The Radio Boys' First Wireless
The Radio Boys at Mountain Pass
Ralph of The Roundhouse
Ralph on the Army Train, Etc.

With Foreword by Jack Binns

Illustrated

[Illustration: THE MAN WAS EVIDENTLY RECEIVING A MESSAGE.
The Radio Boys Trailing a Voice. Page 153]

New York
Grosset & Dunlap
Publishers

Made in the United States of America

BOOKS FOR BOYS
BY ALLEN CHAPMAN

12mo. Cloth. Illustrated.

THE RADIO BOYS SERIES
(Trademark Registered)

THE RADIO BOYS' FIRST WIRELESS
Or Winning the Ferberton Prize

THE RADIO BOYS AT OCEAN POINT
Or The Message that Saved the Ship

THE RADIO BOYS AT THE SENDING STATION
Or Making Good in the Wireless Room

THE RADIO BOYS AT MOUNTAIN PASS
Or The Midnight Call for Assistance

THE RADIO BOYS TRAILING A VOICE
Or Solving a Wireless Mystery

THE RAILROAD SERIES

RALPH OF THE ROUNDHOUSE
Or Bound to Become a Railroad Man

RALPH IN THE SWITCH TOWER
Or Clearing the Track

RALPH ON THE ENGINE
Or The Young Fireman of the Limited Mail

RALPH ON THE OVERLAND EXPRESS
Or The Trials and Triumphs of a Young Engineer

RALPH THE TRAIN DESPATCHER
Or The Mystery of the Pay Car

RALPH ON THE ARMY TRAIN
Or The Young Railroader's Most Daring Exploit

GROSSET & DUNLAP, Publishers, New York

Copyright, 1922, By
GROSSET & DUNLAP

The Radio Boys Trailing a Voice

FOREWORD

BY JACK BINNS

Within a comparatively short time after this volume is published the
human voice will be thrown across the Atlantic Ocean under conditions
that will lead immediately to the establishment of permanent telephone
communication with Europe by means of radio.

Under the circumstances therefore the various uses of radio which are so
aptly outlined in it will give the reader an idea of the tremendous
strides that have been made in the art of communicating without wires
during the past few months.

Of these one of the most important, which by the way is dealt with to a
large extent in the present volume, is that of running down crooks. It
must not be forgotten that criminals, and those criminally intent are
not slow to utilize the latest developments of the genius of man, and
radio is useful to them also. However, the forces of law and order
inevitably prevail, and radio therefore is going to be increasingly
useful in our general police work.

Another important use, as outlined in this volume, is in the detection
of forest fires, and in fact generally protecting forest areas in
conjunction with aircraft. With these two means hundreds of thousands of
acres can now be patrolled in a single day more efficiently than a few
acres were previously covered.

Radio is an ideal boy's hobby, but it is not limited to youth.
Nevertheless it offers a wonderful scope for the unquenchable enthusiasm
that always accompanies the application of youthful endeavor, and it is
a fact that the majority of the wonderful inventions and improvements
that have been made in radio have been produced by young men.

Since this book was written there has been produced in this country the
most powerful vacuum tube in the world. In size it is small, but in
output it is capable of producing 100 kilowatts of electrical power.
Three such tubes will cast the human voice across the Atlantic Ocean
under any conditions, and transmit across the same vast space the
world's grandest music. Ten of these tubes joined in parallel at any of
the giant transmitting wireless telegraph stations would send telegraph
code messages practically around the world.

[Illustration: author's signature "Jack Binns"]

CONTENTS

    I.  Splintering Glass                 9
   II.  In a Dilemma                     20
  III.  The Stuttering Voice             31
   IV.  A Puzzling Mystery               43
    V.  Marvels of Wireless              51
   VI.  The Forest Ranger                61
  VII.  Radio and the Fire Fiend         70
 VIII.  Near Disaster                    77
   IX.  A Happy Inspiration              83
    X.  The Escaped Convict              91
   XI.  Down the Trap Door               99
  XII.  Groping in Darkness             106
 XIII.  Cunning Scoundrels              112
  XIV.  A Daring Holdup                 119
   XV.  Off to the Woods                127
  XVI.  Put to the Test                 136
 XVII.  The Bully Gets a Ducking        143
XVIII.  A Startling Discovery           151
  XIX.  The Robbers' Code               160
   XX.  On the Trail                    168
  XXI.  The Glimpse Through the Window  177
 XXII.  A Nefarious Plot                185
XXIII.  Preparing an Ambush             193
 XXIV.  Lying in Wait                   202
  XXV.  An Exciting Struggle            208

CHAPTER I

SPLINTERING GLASS

"You fellows want to be sure to come round to my house to-night and
listen in on the radio concert," said Bob Layton to a group of his
chums, as they were walking along the main street of Clintonia one day
in the early spring.

"I'll be there with bells on," replied Joe Atwood, as he kicked a piece
of ice from his path. "Trust me not to overlook anything when it comes
to radio. I'm getting to be more and more of a fan with every day that
passes. Mother insists that I talk of it in my sleep, but I guess she's
only fooling."

"Count on yours truly too," chimed in Herb Fennington. "I got stirred up
about radio a little later than the rest of you fellows, but now I'm
making up for lost time. Slow but sure is my motto."

"Slow is right," chaffed Jimmy Plummer. "But what on earth are you sure
of?"

"I'm sure," replied Herb, as he deftly slipped a bit of ice down Jimmy's
back, "that in a minute you'll be dancing about like a howling dervish."

His prophecy was correct, for Jimmy both howled and danced as he tried
vainly to extricate the icy fragment that was sliding down his spine.
His contortions were so ludicrous that the boys broke into roars of
laughter.

"Great joke, isn't it?" snorted Jimmy, as he bent nearly double. "If you
had a heart you'd lend a hand and get this out."

"Let's stand him on his head," suggested Joe. "That's the only thing I
can think of. Then it'll slide out."

Hands were outstretched in ready compliance, but Jimmy concluded that
the remedy was worse than the presence of the ice and managed to keep
out of reach.

"Never mind, Jimmy," said Bob consolingly. "It'll melt pretty soon,
anyhow."

"Yes, and it'll be a good thing for Jimmy to grin and bear it," added
Herb brightly. "It's things like that that develop one's character."

"'It's easy enough to be pleasant, when life moves along like a song,
but the man that's worth while, is the man who can smile when
everything's going dead wrong,'" quoted Joe.

Jimmy, not at all comforted by these noble maxims, glared at his
tormentors, and at last Bob came to his relief, and, putting his hand
inside his collar, reached down his back and brought up the piece of
ice, now greatly reduced in size.

"Let's have it," demanded Jimmy, as Bob was about to throw it away.

"What do you want it for?" asked Bob. "I should think you'd seen enough
of it."

"On the same principle that a man likes to look at his aching tooth
after the dentist has pulled it out," grinned Joe.

"Don't give it to him!" exclaimed Herb, edging away out of reach, justly
fearing that he might feel the vengeance of the outraged Jimmy.

"You gave it to him first, so it's his," decided Bob, with the wisdom of
a Solomon, as he handed it over to the victim.

Jimmy took it and started for Herb, but just then Mr. Preston, the
principal of the high school, came along and Jimmy felt compelled to
defer his revenge.

"How are you, boys?" said Mr. Preston, with a smile. "You seem to be
having a good time."

"Jimmy is," returned Herb, and Jimmy covertly shook his fist at him.
"We're making the most of the snow and ice while it lasts."

"Well, I don't think it will last much longer," surmised Mr. Preston, as
he walked along with them. "As a matter of fact, winter is 'lingering in
the lap of spring' a good deal longer than usual this year."

"I suppose you had a pleasant time in Washington?" remarked Joe
inquiringly, referring to a trip from which the principal had returned
only a few days before.

"I did, indeed," was the reply. "To my mind it's the most interesting
city in the country. I've been there a number of times, and yet I always
leave there with regret. There's the Capitol, the noblest building on
this continent and to my mind the finest in the world. Then there's the
Congressional Library, only second to it in beauty, and the Washington
Monument soaring into the air to a height of five hundred and fifty-five
feet, and the superb Lincoln Memorial, and a host of other things
scarcely less wonderful.

"But the pleasantest recollection I have of the trip," he went on, "was
the speech I heard the President make just before I came away. It was
simply magnificent."

"It sure was," replied Bob enthusiastically. "Every word of it was worth
remembering. He certainly knows how to put things."

"I suppose you read it in the newspaper the next day," said Mr. Preston,
glancing at him.

"Better than that," responded Bob, with a smile. "We all heard it over
the radio while he was making it."

"Indeed!" replied the principal. "Then you boys heard it even before I
did."

"What do you mean?" asked Joe, in some bewilderment. "I understood that
you were in the crowd that listened to him."

"So I was," Mr. Preston answered, in evident enjoyment of their
mystification. "I sat right before him while he was speaking, not more
than a hundred feet away, saw the motion of his lips as the words fell
from them and noted the changing expression of his features. And yet I
say again that you boys heard him before I did."

"I don't quite see," said Herb, in great perplexity. "You were only a
hundred feet away and we were hundreds of miles away."

"And if you had been thousands of miles away, what I said would still be
true," affirmed Mr. Preston. "No doubt there were farmers out on the
Western plains who heard him before I did.

"You see it's like this," the schoolmaster went on to explain. "Sound
travels through the air to a distance of a little over a hundred feet in
the tenth part of a second. But in that same tenth of a second that it
took the President's voice to reach me in the open air radio could have
carried it eighteen thousand six hundred miles."

"Whew!" exclaimed Jimmy. "Eighteen thousand six hundred miles! Not feet,
fellows, but miles!"

"That's right," said Bob thoughtfully. "Though I never thought of it in
just that way before. But it's a fact that radio travels at the rate of
one hundred and eighty-six thousand miles a second."

"Equal to about seven and a half times around the earth," observed the
principal, smiling. "In other words, the people who were actually
sitting in the presence of the President were the very last to hear what
he said.

"Put it in still another way. Suppose the President were speaking
through a megaphone in addition to the radio and by the use of the
megaphone the voice was carried to people in the audience a third of a
mile away. By the time those persons heard it, the man in the moon could
have heard it too--that is," he added, with a laugh, "supposing there
really were a man in the moon and that he had a radio receiving set."

"It surely sounds like fairyland," murmured Joe.

"Radio is the fairyland of science," replied Mr. Preston, with
enthusiasm, "in the sense that it is full of wonder and romance. But
there the similarity ceases. Fairyland is a creation of the fancy or the
imagination. Radio is based upon the solid rock of scientific truth. Its
principles are as certain as those of mathematics. Its problems can be
demonstrated as exactly as that two and two make four. But it's full of
what seem to be miracles until they are shown to be facts. And there's
scarcely a day that passes without a new one of these 'miracles' coming
to light."

He had reached his corner by this time, and with a pleasant wave of his
hand he left them.

"He sure is a thirty-third degree radio fan," mused Joe, as they watched
his retreating figure.

"Just as most all bright men are becoming," declared Bob. "The time is
coming when a man who doesn't know about radio or isn't interested in it
will be looked on as a man without intelligence."

"Look here!" exclaimed Jimmy suddenly. "What's become of my piece of
ice?"

He opened his hand, which was red and wet and dripping.

"That's one on you, Jimmy, old boy," chuckled Joe. "It melted away while
you were listening to the prof."

"It's an ill wind that blows nobody good," said Herb complacently.
"Jimmy meant to put that down my back."

"Oh, there are plenty of other pieces," said Jimmy, as he picked one up
and started for Herb.

Herb started to run, but slipped and fell on the icy sidewalk.

"You know what the Good Book says," chaffed Joe. "The wicked stand on
slippery places."

"Yes, I see they do," replied Herb, as quick as a flash, looking up at
him. "But I can't."

The laugh was on Joe, and Herb felt so good over the retort that he did
not mind the fall, though it had jarred him considerably. He scrambled
to his feet and brushed off his clothes, while Jimmy, feeling that his
comrade had been punished enough, magnanimously threw away the piece of
ice that was to have been the instrument of his vengeance.

"The reason why I wanted you fellows to be sure to be on hand to-night,"
resumed Bob, as they walked along, "was that I saw in the program of the
Newark station in the newspaper this morning that Larry Bartlett was
down for an entirely new stunt. You know what a hit he made with his
imitations of birds."

"He sure did," agreed Joe. "To my mind he had it all over the birds
themselves. I never got tired listening to him."

"He certainly was a dabster at it," chimed in Jimmy.

"Now he's going in to imitate animals," explained Bob. "I understand
that he's been haunting the Zoo for weeks in every minute of his spare
time studying the bears and lions and tigers and elephants and snakes,
and getting their roars and growls and trumpeting and hisses down to a
fine point. I bet he'll be a riot when he gives them to us over the
radio."

"He sure will," assented Herb. "He's got the natural gift in the first
place, and then he practices and practices until he's got everything
down to perfection."

"He's a natural entertainer," affirmed Bob. "I tell you, fellows, we
never did a better day's work than when we got Larry that job at the
sending station. Not only was it a good thing for Larry himself when he
was down and out, but think of the pleasure he's been able to give to
hundreds of thousands of people. I'll bet there's no feature on the
program that is waited for more eagerly than his."

By this time the boys had reached the business portion of the town and
the short spring day was drawing to a close. Already lights were
beginning to twinkle in the stores that lined both sides of the street.

"Getting near supper time," remarked Bob. "Guess we'd better be getting
along home. Don't forget to come--Gee whiz!"

The ejaculation was wrung from him by a snowball that hit him squarely
in the breast, staggering him for a moment.

Bang! and another snowball found a target in Joe. It struck his shoulder
and spattered all over his face and neck.

"That felt as though it came from a gun!" he exclaimed. "It's the
hardest slam I ever got."

"Who did it?" demanded Bob, peering about him in the gathering darkness.

Halfway up the block they saw a group of dark figures darting into an
alleyway.

"It's Buck Looker and his crowd!" cried Jimmy. "I saw them when they ran
under that arc light."

"Just like that crowd to take us unawares," said Bob. "But if they're
looking for a tussle we can accommodate them. Get busy, fellows, and let
them have something in return for these two sockdolagers."

They hastily gathered up several snowballs apiece, which were easily
made because the snow was soft and packed readily, and ran toward the
alleyway just in time to see Buck and his crowd emerging from their
hiding place.

There was a spirited battle for a few minutes, each side making and
receiving some smashing hits. Buck's gang had the advantage in that they
had a large number of missiles already prepared, and even in the
excitement of the fight the radio boys noticed how unusually hard they
were.

"Must have been soaking them in water until they froze," grunted Jimmy,
as one of them caught him close to the neck and made him wince.

As soon as their extra ammunition was exhausted and the contending
forces in this respect were placed more on a footing of equality, Buck
and his cronies began to give ground before the better aim and greater
determination of Bob and his comrades.

"Give it to them, fellows!" shouted Bob, as the retreat of their
opponents was rapidly becoming a rout.

At the moment he called out, the progress of the fight had brought the
radio boys directly in front of the windows of one of the largest
drygoods stores in the town.

In the light that came from the windows Bob saw a snowball coming
directly for his head. He dodged, and----

Crash! There was the sound of splintering glass, and the snowy missile
whizzed through the plate glass window!

CHAPTER II

IN A DILEMMA

There was a moment of stupor and paralysis as the meaning of the crash
dawned upon the radio boys.

Buck and his crowd had vanished and were footing it up the fast-darkening
street at the top of their speed.

The first impulse of the radio boys was to follow their example. They
knew that none of them was responsible for the disaster, and they were
of no mind to be sacrificed on behalf of the gang that had attacked
them. And they knew that in affairs of that kind the ones on the ground
were apt to suffer the more severely.

They actually started to run away, but had got only a few feet from the
scene of the smash when Bob, who had been thinking quickly, called a
halt.

"None of this stuff for us, fellows," he declared. "We've got to face
the music. I'm not going to have a hunted feeling, even if we succeeded
in getting away. We know we didn't do it and we'll tell the plain truth.
If that doesn't serve, why so much the worse for us. But at any rate we
won't be despising ourselves as cowards."

As usual, his comrades accorded him the leadership and fell in with his
plan, although it was not without many misgivings that they awaited the
coming of the angry proprietor of the place, who had already started in
pursuit of them, accompanied by many others who had been attracted by
the crash and whose numbers were being rapidly augmented.

"Here are the fellows that smashed my window!" cried Mr. Larsen, the
proprietor of the drygoods store, rushing up to them and shaking his
fist in their faces. "Where are the police?" he shouted, looking around
him. "I'll have them arrested for malicious damage."

And while he faced them, gesticulating wildly, his face purple with
anger and excitement, it may be well for the benefit of those who have
not read the preceding volumes of this series to tell briefly who the
radio boys are and what had been their adventures before the time this
story opens.

The acknowledged leader of the boys was Bob Layton, son of a prosperous
chemist of Clintonia, in which town Bob had been born and brought up.
Mr. Layton was a respected citizen of the town and foremost in its civic
activities. Clintonia was a thriving little city of about ten thousand
population, situated on the Shagary River, about seventy-five miles from
the city of New York.

Bob at the beginning of this story was about sixteen years old, tall and
stalwart and a clean-cut specimen of upstanding American youth. He was
of rather dark complexion and had a pair of eyes that looked straight at
one. Those eyes were usually merry, but could flash with indignation
when circumstances required it. He was never on the lookout for trouble,
but was always ready to meet it half way, and his courageous character
together with his vigorous physique had made him prominent in the sports
of the boys of his own age. He was a crack baseball player and one of
the chief factors of the high school football eleven. No one in
Clintonia was held in better liking.

Bob's special chum was Joe Atwood, son of the leading physician of the
town. Joe was fair in complexion and sturdy in makeup. He and Bob had
been for many years almost inseparable companions, Bob usually acting as
captain in anything in which they might be engaged, while Joe served as
first mate. The latter had a hot temper, and his impulsiveness sometimes
got him into trouble and would have involved him in scrapes oftener if
it had not been for the cooler head and steadying influence of Bob.

Two other friends of the boys who were almost always in their company
were Herb Fennington, whose father kept a large general store in the
town, and Jimmy Plummer, son of a respected carpenter and contractor.
Herb was of a rather indolent disposition, but was jolly and
good-natured and always full of jokes, some of them good, others poor,
which he frequently sought to spring on his companions.

Jimmy was a trifle younger than his mates, fat and round and excessively
fond of the good things of life. His liking for that special dainty had
gained him the nickname of "Doughnuts," and few of such nicknames were
ever more fittingly bestowed.

Apart from the liking that drew them together, the boys had another link
in their common interest in radio. From the time that this wonderful new
science had begun to spread over the country with such amazing rapidity,
they had been among the most ardent "fans." Everything that they could
read or learn on the subject was devoured with avidity, and they were
almost constantly at the home of one or the other, listening in on their
radio sets and, lately, sending messages, in the latter of which they
had now attained an unusual degree of proficiency.

In decided contrast to Bob and his friends was another group of
Clintonia youth, between whom and the radio boys there was a pronounced
antipathy. The leader of this group was Buck Looker, a big overgrown,
hulking boy, dull in his studies and a bully in character. His two
special cronies were Carl Lutz, a boy of about his own age, and Terry
Mooney, both of them noted for their mean and sneaking dispositions.
Buck lorded it over them, and as his father was one of the richest men
in the town they cringed before him and were always ready to back him up
in any piece of meanness and mischief.

The enthusiasm of Bob and his friends for radio was fostered by the help
and advice of the Reverend Doctor Dale, the clergyman in charge of the
Old First Church of Clintonia, who, in addition to being an eloquent
preacher, was keenly interested in all latter-day developments of
science, especially radio. Whenever the boys got into trouble with their
sets they knew that all they had to do was to go to the genial doctor
and be helped out of their perplexities.

An incident that gave a great impetus to their interest in the subject
was the offering of prizes by Mr. Ferberton, the member of Congress for
their district, for the best radio sets turned out by the boys of his
congressional district by their own endeavors. Bob, Joe, and Jimmy
entered into this competition with great zest. Herb with his habitual
indolence kept out of it.

While the boys were engrossed with their radio experiments an incident
happened in town that led them into many unexpected adventures. An
automobile run by a visitor in town, a Miss Nellie Berwick, got out of
her control and dashed through the window of a store. Bob and Joe, who
happened to be at hand, rescued the girl from imminent peril, while Herb
and Jimmy did good work in curbing the fire that followed the accident.

How the boys learned of the orphan girl's story, got on the track of the
rascal who had tried to swindle her and forced him to make restitution;
what part the radio played in bringing the fellow to terms; how they
detected and thwarted the plans of Buck Looker and his cronies to wreck
their sets; are told in the first volume of this series entitled: "The
Radio Boys' First Wireless; Or, Winning the Ferberton Prize."

That summer the chums went to Ocean Point on the seashore, where many of
the Clintonia folks had established a little bungalow colony of their
own. What adventures they met with there; what strides they made in the
practical work of radio; how they were enabled by their knowledge and
quick application of it to save a storm-tossed ship on which members of
their own families were voyaging; how they ran down and captured the
scoundrel Cassey who had knocked out with a blackjack the operator at
the sending station and looted his safe--these and many more incidents
are narrated in the second volume of this series entitled: "The Radio
Boys at Ocean Point; Or, The Message That Saved the Ship."

While the summer season was yet at its height, the boys had occasion to
rescue the occupants of a rowboat that had been run down by men in a
stolen motor boat. The two rescued youths proved to be vaudeville
actors, and the boys grew very friendly with them. The injury that
crippled one of them, Larry Bartlett; the false accusation brought
against him by Buck Looker; the way in which the boys succeeded in
getting work for Larry at the sending station, where his remarkable gift
of mimicry received recognition; how they themselves were placed on the
broadcasting program, and the clever way in which they trapped the
motor-boat thieves; are told in the third volume of the series,
entitled: "The Radio Boys at the Sending Station; Or, Making Good in the
Wireless Room."

The coming of fall brought the boys back to Clintonia, where, however,
the usual course of their studies was interrupted by an epidemic that
made necessary for a time the closing of the schools. This gave the
radio boys an opportunity to make a trip to Mountain Pass, a popular
resort in the hills. Here they came in contact with a group of plotters
who were trying to put through a nefarious deal and were able to thwart
the rascals through the use of radio. By that same beneficent science
too they were able to save a life when other means of communication were
blocked. And not the least satisfactory feature was the utter
discomfiture they were able to visit upon Buck Looker and his gang.
These and many other adventures are told in the fourth volume of the
series, entitled: "The Radio Boys at Mountain Pass; Or, The Midnight
Call for Assistance."

And now to return to the radio boys as they stood facing the angry
storekeeper amid a constantly growing throng of curious onlookers. They
had been in many tighter fixes in their life but none that was more
embarrassing.

"I'll have them arrested!" the storekeeper repeated, his voice rising to
a shrill treble.

"Now look here," replied Bob. "Suppose you cut out this talk of having
us arrested. In the first place, we didn't break your window. In the
second place, if we had it wouldn't be a matter of arrest but of making
good the damage."

"All right then," said Mr. Larsen eagerly, catching at the last word.
"Make good the damage. It will cost at least two hundred dollars to
replace that window."

"I think you're a little high," returned Bob. "But that doesn't matter.
I didn't say that we'd make the damage good. I said that if we'd broken
it, it would be a matter of making good. But we didn't break it, and
that lets us out I'll say."

"It's easy to say that," sneered the merchant. "How do I know that you
didn't break it? It would of course be natural for you to try to lie out
of it."

"It wouldn't be natural for us to lie out of it," replied Bob,
controlling his temper with difficulty. "That isn't our way of doing
things. Why do you suppose we stayed here when it would have been
perfectly easy for us to get away? It wasn't a snowball we threw that
broke your window. It was one thrown by the fellows we were fighting
with."

"Always the other fellow that does it!" replied the storekeeper angrily.
"Who was that other fellow or fellows then? Tell me that. Come on now,
tell me that."

Bob kept silent. He had no love for Buck Looker and his gang, who had
always tried to injure him, but he was not going to inform.

"See," said Mr. Larsen, misunderstanding his silence. "When I ask you,
you can't tell me. You're the fellows that did it, all right, and you'll
pay me for it or I'll have you put in jail, that's what I'll do."

"I saw the fellows who were firing snowballs in this direction," spoke
up Mr. Talley, a caterer, pushing his way through the throng. "I nearly
bumped into them as they were running away. Buck Looker was one of them.
I saw his face plainly and can't be mistaken. The others I'm not so sure
of, but I think they were Carl Lutz and Terry Mooney.

"For my part, Mr. Larsen," he continued, "I don't see how a snowball
could break that heavy plate-glass window, anyway. My windows are no
heavier, and they've often had snowballs come against them without doing
any harm. Are you sure it wasn't something else that smashed the glass?"

"Dead sure," replied Larsen. "Come inside and see for yourself."

He led the way into his store, and Mr. Talley, the boys, and a number of
others crowded in after him.

"Look," said Larsen, pointing to a piece of dress goods that had been
hanging in the window. "See where the snow has splashed against it?
There's no question that a snowball did it. You can see the bits of snow
around here yet if you'll only look."

This was true and the evidence seemed conclusive. But just then Bob's
keen eyes detected something else. He stooped down and brought up quite
a large sharp-edged stone which still had some fragments of snow
adhering to it and held it up for all to see.

"Here's the answer," he said. "This stone was packed in the snowball,
and that is why it smashed the window!"

THE STUTTERING VOICE

There was a stir of interest and exclamations of surprise as those in
the store crowded closer to get a better view.

"That explains it," said Mr. Talley, as he examined the missile. "I was
sure that no mere ball of snow could break that heavy window. To put
such a stone in a snowball was little less than criminal," he went on
gravely. "If that had hit any one on the temple it would almost
certainly have killed him."

"It was coming straight for my head when I dodged," said Bob.

"That's another proof that it wasn't any ball we threw that broke the
window," put in Joe. "Each one of us is willing to swear that there was
no stone in any ball that we threw."

"Not only then but at any time," put in Herb. "Only a mean coward would
do a thing like that. None of us has done it any time in his life."

"I believe that," replied Mr. Talley. "I've known all you boys ever
since you were little kids and I know you wouldn't be capable of it."

"That's all very well," said Mr. Larsen. "But that doesn't pay for my
window. Whether any of you boys threw the ball or not you can't deny
that you were engaged in a snowball fight right in front of my windows.
If the fight hadn't been going on the window wouldn't have been
smashed."

There was a certain amount of justice in this, and the boys were fair
enough to acknowledge it.

"I suppose you are right there, Mr. Larsen," said Bob regretfully. "We
ought to have kept out of range of the windows, but in the excitement we
forgot all about that. Then, too, we never would have supposed that any
ordinary snowball would have broken the window. Perhaps that was in the
back of our minds, if we thought of it at all."

"Is the window insured?" queried Mr. Talley.

"Yes, it is," answered the storekeeper.

"Well, then, that lets you out," remarked Mr. Talley, with a note of
relief in his voice. "That puts the matter up to the insurance company.
If they want to take any legal steps they can; and of course they ought
to be compensated by the parents of the boy who may be found guilty of
having thrown the ball with a stone in it. For my part, I doubt very
much that it can ever be proved, unless the boy himself owns up to it."

"Think of Buck Looker ever owning up to anything!" muttered Jimmy.

"As for these boys," continued Mr. Talley, "I am perfectly sure in my
own mind that they are telling the truth. You'll have to look for the
culprit in the other crowd, and I've already told you who they are, or
who one of them is, at least."

"Well," said the storekeeper, who by this time had cooled down
considerably, "that, I suppose, will be something for the insurance
company to settle. But by the terms of my contract with them I'll have
to help them all I can to find out the responsible party, and I'll have
to give them the names of all the boys concerned in the fight."

"That's all right," responded Bob. "You know our folks and you know that
they're good for any judgment that may be found against them. But I'm
sure it will be somebody else that will have to pay the bill."

There was nothing more to be done for the present, and the boys filed
out of the store, after having expressed their thanks to Mr. Talley for
the way he had championed their cause.

"Gee!" murmured Joe, as they went up the street toward their homes, "I
know how a fellow feels now after he's been put through the third
degree."

"It was rather a hot session," agreed Bob. "But I'm glad we had it out
with him instead of running away. It's always best to take the bull by
the horns. And you can't blame Mr. Larsen for feeling sore about it. Any
one of us would probably have felt the same way."

"Sure thing," admitted Herb. "But think of that dirty trick of Buck
Looker in putting stones in snowballs! It wasn't only that one that went
through the window. Every time I got hit it made me jump."

"Same here," said Jimmy. "I was thinking all the time that they were the
hardest snowballs I ever felt, but it never came into my mind that there
were stones in them."

"Trust Buck to be up to every mean trick that any one ever thought of,"
returned Bob. "He hasn't got over the way we showed him up at Mountain
Pass. He thought he had us dead to rights in the matter of that burned
cottage, and it made him wild to see the way we came out on top. He and
his gang would do anything to get even."

"It will be interesting to see what he'll say when this matter of the
window is put up to him and his pals," remarked Herb.

"Not a doubt in the world what he'll say," replied Joe. "He'll swear
till he's blue in the face that he never dreamed of using a stone in the
snowballs. Do you remember how he told us that he'd lie in court to keep
us from putting anything over on him? Any one that expects to get the
truth out of Buck is barking up the wrong tree. I guess the insurance
company would better kiss their money good-by."

"I'm afraid so," returned Bob. "It was dark and there probably weren't
any witnesses who saw them put the stones in, and it is likely that the
company will have to let the matter drop."

The lads had reached Bob's gate by this time, and they separated with a
promise to come over and listen in on the radio later on.

Bob told the whole story to his parents at the supper table that night,
and his father and mother listened with great interest and some concern.

"I'm sorry you were mixed up in the thing at all, Bob," his father
remarked thoughtfully. "Being in it, however, you acted just as you
should have done. Just how far you and your friends may be held
responsible, in case they can't find the one who actually threw the ball
that broke the window, I'm not lawyer enough to say. It's barely
possible that there may be some ground for action on the score of
culpable carelessness in taking part in a snowball fight in front of
store windows, and of course you were wrong in doing that. But the total
amount involved is not very great after all, and it would be divided up
among the parents of the four of you, so there's nothing much to worry
about. It would gall me though to have to pay for damages that were
really caused by that cub of Looker's."

"I'm sorry, Dad," said Bob. "I'm hoping yet that something may develop
that will put the thing up to Buck, or whoever it was of his gang that
actually threw the ball."

"Let's hope so," returned Mr. Layton, though without much conviction in
his voice, and dismissed the subject.

A little while afterward the other three boys came over to Bob's house
to listen in on the radio concert. So much time, however, had been taken
up in discussing the afternoon's adventure that they missed Larry's
offering, which was among the first on the program. This was a keen
disappointment, which was tempered, however, by the probability that
they could hear him some evening later in the week.

"Sorry," remarked Joe. "But it only means that we still have a treat in
store when the old boy begins to roar and growl and hiss so as to make
us think that a whole menagerie has broken loose and is chasing us. In
the meantime we can fix up that aerial so as to get a little better
results."

"Funny thing I noticed the other day," remarked Bob, as they embarked
upon some experiments.

"All sorts of funny things in the radio game," observed Joe. "Something
new turns up every day. Things in your set that you think you can't do
without you find you can do without and get results just about as
usual."

"Just what I was going to tell you," returned Bob. "You must be
something of a prophet."

"Oh, I wouldn't go quite so far as to say that," replied Joe, with mock
modesty.

"Isn't he the shrinking violet?" chaffed Jimmy.

"Stop your kidding, you boobs, and let a regular fellow talk," chided
Bob. "What I was going to say was that while I was tinkering with the
set I disconnected the ground wire. Of course I thought that would put
the receiver out of business for the time, and I was almost knocked
silly when I found that I could hear the concert that was going on just
about as well as though the wire had been connected. How do you account
for that?"

"Don't account for it at all," replied Herb. "Probably just a freak, and
might not happen again in a thousand times. Likely it was one of the
unexplainable things that happen once in a while. Maybe there was a
ground connection of some kind, if not by the wire. I wouldn't bank on
it."

"It's queer, too, how many kinds of things can be used as aerials," put
in Joe. "I heard the other day of a man in an apartment house where the
owner objected to aerials, who used the clothesline for that purpose.
The wire ran through the rope, which covered it so that it couldn't be
seen. It didn't prevent its use as a clothesline either, for he could
hear perfectly when the wash was hanging on it."

"Oh, almost anything will do as an aerial," chimed in Jimmy. "The rib of
an umbrella, the rainspout at the side of the house, the springs of a
bed give good results. And that's one of the mighty good things about
radio. People that have to count the pennies don't have to buy a lot of
expensive materials. They can put a set together with almost any old
thing that happens to be knocking around the house."

Bob had been working steadily, and, as the room was warm, his hands were
moist with perspiration. He had unhooked an insulated copper wire that
led to his outside aerial. His head phones were on, as he had been
listening to the radio concert while he worked.

"I'll have to miss the rest of that selection, I guess," he remarked
regretfully, as he unhooked the wire. "It's a pity, too, for that's one
of the finest violin solos I ever heard. Great Scott! What does that
mean?"

The ejaculation was wrenched from him by the fact that although he had
disconnected the wire he still heard the music--a little fainter than
before but still with every note distinct.

He could scarcely believe his ears and looked at his friends in great
bewilderment.

"What's the matter?" asked Joe, jumping to his feet. "Get a shock?"

"Not in the sense you mean, but in another way, yes," replied Bob, still
holding the exposed end of the copper wire in his fingers. "What do you
think of that, fellows? I'm an aerial!"

"Come out of your trance," adjured Herb unbelievingly. "They talk that
way in the insane asylums."

"Clap on your headphones," cried Bob, too intent on his discovery to pay
any attention to the gibe.

They did so, and were amazed at hearing the selection as plainly as did
Bob himself.

The latter had been holding the disconnected wire so that his fingers
just touched the uncovered copper portion at the end. Now he hastily
scraped off several inches of the insulation and grasped the copper wire
with his hand. Instantly the volume of sound grew perceptibly greater.

Hardly knowing what to make of it, he scraped off still more of the
insulation.

"Here, you fellows," he shouted. "Each of you take hold of this."

Joe was the first to respond, and the sound became louder. Then Herb and
Jimmy followed suit, and it was evident that they served as amplifiers,
for with each additional hand the music swelled to greater volume.

The boys looked at each other as if asking whether this was all real or
if they had suddenly been transferred to some realm of fancy. They would
not have been greatly surprised to wake up suddenly and find that they
had been dreaming.

But there was no delusion about it and they listened without saying
another word until, in a glorious strain of melody, the selection came
to an end. Nor did they break the silence until a band orchestra was
announced and crashed into a brilliant overture.

While it was still in full swing, Bob had an inspiration. He took off
his headphones and clamped them on to the phonograph that stood on a
table near by. Instantly the music became intensified and filled the
room. When all their hands were on the wire, it became so loud that they
had to close the doors of the phonograph.

"Well," gasped Bob, when the last strain had died away and the
demonstration was complete, "that's something new on me."

"Never dreamed of anything like it," said Joe, sinking back in his
chair. "Of course we know that the human body has electrical capacity
and that operators sometimes have to use metal shields to protect the
tube from the influence of the hand. And in our loop aerial at Ocean
Point you noticed that the receptivity of the tube was modified when we
touched it with our fingers."

"Of course, in theory," observed Bob thoughtfully, "the human body
possesses inductance as well as capacity, and so might serve as an
antenna. But I never thought of demonstrating it in practice."

"So Bob is an aerial," grinned Herb. "I always knew he was a 'live
wire,' but I never figured him out as an antenna."

"And don't forget that if Bob is an aerial we're amplifiers," put in
Jimmy.

"There's glory enough for all," laughed Joe. "We'll have to tell Doctor
Dale and Frank Brandon about this. We've got so many tips from them that
it's about time we made it the other way around."

They were so excited about this new development which they had stumbled
upon purely through accident that they sat talking about it for a long
time until Bob chanced to look at his watch.

"Just have time for the last selection," he remarked, as he reconnected
the aerial. "We'll wind up in the regular way this time. It's an aria
from Lucia and I don't want to miss it."

He had some difficulty in making his adjustment, as there was a lot of
interference at the moment.

"Raft of amateurs horning in," he muttered. "All of them seem to have
chosen just this time to do it. I wonder----"

He stopped as though he had been shot, and listened intently. Then he
beckoned to the others to adjust their headphones.

Into the receiver was coming a succession of stuttering sounds that
eventually succeeded in framing intelligible words. Ordinarily this
might have provoked laughter, but not now. They had heard that voice
before.

It was the voice of Dan Cassey!

CHAPTER IV

A PUZZLING MYSTERY

For the second time that evening the radio boys thought they must be
dreaming.

Cassey! Cassey the swindler, whom they had compelled to make restitution
to the victim he had wronged. Cassey the thug, whom they had captured in
that wild chase after he had looted the safe and nearly killed the
operator in the sending station. Cassey the convict, who, to their
certain knowledge, had been sentenced to a long term in prison.

What was Cassey doing over the radio? That it was that scoundrel they
had no doubt. The stuttering, the tones of the voice, the occasional
whistle which he indulged in in order to go on--all these things they
recognized perfectly. It was the wildest kind of improbability that he
had a double anywhere who could reproduce him so perfectly.

Gone now was any thought of the aria from Lucia. Bob motioned
frantically to Jimmy to hand him a pencil and a sheet of paper. Then he
jotted down the words, as after great efforts they fell one by one from
the stutterer's lips. As Bob did this he bent over the paper in frowning
perplexity. The words themselves were intelligible, but they did not
seem to make sense, nor was there anywhere a connected sentence.

Finally the stammering voice ceased, and after they had waited several
minutes longer to make sure that it would not resume, the boys took off
their headphones and gazed at each other in utter bewilderment.

"Well, I'll be blessed!" exclaimed Joe. "That villain Cassey, of all men
on the face of the earth! What do you make of it, Bob?"

"I don't know what to make of it," confessed Bob. "It has simply knocked
me endways. I never thought to hear of that rascal again for the rest of
my life. Yet here he is, less than a year after he's been sentenced,
talking over the radio."

"Perhaps he's received a pardon," hazarded Jimmy.

"Not at all likely," answered Bob. "It isn't as though he were a first
offender. He's old in crime. You remember the raking over the judge gave
him when he sentenced him. Told him if he had it in his power he'd give
him more than he actually did. No, I think we can dismiss that idea."

"Isn't it possible," suggested Herb, "that he's employed as radio
operator in the prison? He understands sending and receiving all right."

"That doesn't strike me hard either," Bob objected. "Likely enough the
prison is equipped with a wireless set, but it isn't probable that
they'd let a prisoner operate it. It would give him too good a chance to
get in touch with confederates outside the jail. Then, too, his
stuttering would make him a laughing stock.

"The only explanation that I can see," he went on, "is that he's
escaped, and he's sending this message on his own hook. Though what the
message is about is beyond me."

"Just what did you get down?" asked Jimmy curiously. "I caught a few
words, but I don't remember them all."

"It's a regular hodgepodge," replied Bob, spreading out the sheet of
paper, while they all crowded around to read.

"Corn--hay--six--paint--water--slow--sick--jelly," read Joe aloud.
"Sounds to me like the ravings of a delirium patient."

"And yet I'm sure that I got all the words down right," said Bob
perplexedly. "It must be a code of some kind. We can't understand it,
and Cassey didn't mean that any one should except some one person whose
ear was glued to a radiophone. But you can bet that that person
understood it all right."

"I wonder if we couldn't make it out," suggested Herb.

"No harm in trying," said Joe, "though compared to this a Chinese puzzle
is as simple as A B C. Let's take a hack at it, anyhow. We'll each take
a separate sheet of paper and try to get something out of it that makes
sense."

For nearly an hour the boys did their best. They put the words in
different orders, read them forward and backward. But the ideas conveyed
by the separate words were so utterly dissimilar that they could frame
nothing that had the slightest glimmering of sense and they were finally
compelled to give it up.

"If time were money, we'd spend enough on this stuff to make us
bankrupt," Joe remarked, in vast disgust, as he rose to get his cap.
"Dan Cassey was foxy when he made this up. We'll have to give the rascal
credit for that."

"Yes," admitted Herb, "it's the best kind of a code. Any one of those
words might mean any one of a hundred thousand things. A man might spend
a lifetime on it and be no nearer success at the end than he was when he
started. The only way it can be unraveled is by finding the key that
tells what the words stand for. And even that may not exist in written
form. The fellows may simply have committed them to memory.

"I'll tell you what I'll do!" Bob exclaimed. "I'll get the prison
to-morrow on the long distance 'phone and ask them about Cassey. I'll
tell them all about this radio message, and it may be a valuable tip to
them. They may be able to locate the station from which the messages
come, if there are any more of them. You remember how Mr. Brandon
located Cassey's sending station the first time."

Bob was as good as his word, and got in communication with the prison
just before school time. The warden was gruff and inclined to be
uncommunicative at first, but his manner changed remarkably after he
heard of the radio message and he inquired eagerly for the slightest
details.

"Yes, Cassey has escaped," he told Bob. "He got away about two months
ago. He had behaved himself well for the first six months of his
imprisonment, and we made him a trusty. In that capacity he had access
to various parts of the prison and occasionally to my own quarters,
which are in a wing connected with the prison. In some way that hasn't
yet been discovered he got possession of clothes to cover his prison
uniform and got away one day from the yard in which he was working.
Probably with his help, two others got away at the same time. Their
names are Jake Raff and Toppy Gillen, both of them desperate criminals
and in for long terms. Likely enough the three of them are operating
together somewhere. We made a careful search for them and have sent out
descriptions of them to the police of all the important cities in the
United States. But this clue of yours is the only one we have, and it
may prove a most important one. I'll see that the Federal radio
authorities are notified at once. Keep in touch with me and let me know
if you come across anything else that seems to point to Cassey. His
escape is a sore point with me, and I'd be glad to have him once more
behind the bars. You can be sure he'll never get away again until he's
served out the last day of his sentence."

With a warm expression of thanks the warden hung up his telephone
receiver, and Bob hurried off to school to tell his comrades of what he
had learned.

There was no chance for this, however, before recess, as he had been
kept so long at the telephone that he was barely able to reach the
school before the bell rang.

When at last he told them of his talk with the warden, they listened
with spellbound interest.

"So the villain managed to escape, did he?" ruminated Joe. "That's a
black mark against the warden, and it's no wonder he's anxious to get
him back. I'd hate to be in Cassey's shoes if the prison gates ever
close on him again."

"You'd think it would be a comparatively easy matter to capture him,"
suggested Herb. "The fact that he stutters so badly makes him a marked
man."

"You can bet that he doesn't do any more talking than he can help,"
replied Joe. "And, for that matter, I suppose there are a good many
thousand stutterers in the United States. Almost every town has one or
more. Of course it's against him, but it doesn't by any means make it a
sure thing that he'll be nabbed."

Buck Looker and his cronies happened to pass them in the yard just at
that moment and caught the last word. Buck whispered something to Carl
Lutz, and the latter broke out into uproarious laughter.

It was so obviously directed against Joe that his impulsive temper took
fire at once. He stepped up to the trio, despite Bob's outstretched hand
that tried to restrain him.

"Were you fellows laughing at me?" he asked of the three, though his
eyes were fastened directly on Buck's.

"Not especially at you," returned Buck insolently. "But at something you
said."

"And what was that?" asked Joe, coming a step nearer, at which Buck
stepped back a trifle.

"About getting nabbed," he said. "It made me think of some fellows I
know that were nabbed last night for breaking windows."

"Oh, that was it!" remarked Joe, with dangerous calmness while his fist
clenched. "Now let me tell you what it reminds me of. It makes me think
of three cowards who smashed a window last night with a stone packed in
a snowball and then ran away as fast as their legs could carry them.
Perhaps you'd like me to tell you their names?"

"I don't know what you're talking about," retorted Buck, changing color.

"Oh, yes, you do," replied Joe. "And while I'm about it, I'll add that
the fellows who smashed the window were not only cowards, but worse. And
their names are Buck Looker, Carl Lutz and Terry Mooney."

"What's that?" cried Buck, bristling up, while an angry growl arose from
his cronies.

"You heard me the first time," replied Joe; "but to get it into your
thick heads I'll say it again. The cowards, and worse, I referred to are
named Buck Looker, Carl Lutz and Terry Mooney."

CHAPTER V

MARVELS OF WIRELESS

"That's fighting talk," blustered Buck, as he made a pretense of getting
ready to throw off his coat.

"That's precisely what I want it to be," declared Joe, as he tore off
his coat and threw it to the ground.

By this time most of the boys in the school yard had sensed the
tenseness of the situation and had gathered around Joe and Buck, forming
a ring many lines deep.

"A fight!" was the cry.

"Go in, Joe!"

"Soak him, Buck!"

Before Joe's determined attitude and flashing eyes, Buck wavered. He
fingered his coat uncertainly and glanced toward the school windows.

"There's one of the teachers looking out," he declared. "And it's
against the rules to fight on the school grounds. If it wasn't for that
I'd beat you up."

There was a general snicker from the boys at Buck Looker's sudden regard
for the rules of the school.

"Any other place you can think of where you'd like to beat me up?" said
Joe sarcastically. "How about this afternoon after school down by the
river?"

"I----I've got to go out of town this afternoon," Buck stammered. "But
don't you worry. I'll give you all the fight you're looking for the
first chance I get."

Murmurs of derision arose from the crowd, and the flush on the bully's
sour face grew much deeper.

"You're just a yellow dog, Buck!" exclaimed Joe, in disgust. "Have I got
to pull your nose to make you stand up to me?"

He advanced toward him, and Buck retreated. What would have happened
next will never be known, for just at that moment one of the teachers
emerged from the school and came toward the ring. Hostilities at the
moment were out of the question, and the boys began to scatter. Buck
heaved a sigh of evident relief, and now that he felt himself safe, all
his old bluster came back to him.

"It's mighty lucky for you that Bixby came out just then," he declared.
"I was just getting ready to thrash you within an inch of your life."

Joe laughed sarcastically.

"The trouble with you, Buck, is that you spend so much time getting
ready that you never have any time for real fighting," he remarked. "It
took you an awfully long time to get your coat unbuttoned."

"They laugh best who laugh last," growled Buck. "And don't forget that
you fellows have got to pay for that glass you broke."

"You've got another guess coming," replied Joe. "You or one of your gang
broke that glass and we can prove it."

"I wasn't downtown that night at all," said Buck glibly.

"Don't add any more lies to your score," said Joe scornfully. "We've got
you! You and your gang are the only fellows in town who would put stones
in snowballs, anyway."

"If that's all the evidence you've got, it wouldn't go far in a court of
law," sneered Buck. "Any judge would see that you were trying to back
out of it by putting it up to somebody else."

"Perhaps you don't know that Mr. Talley bumped into you while you were
running away," remarked Joe.

This shot told, for Buck had banked on the darkness and had forgotten
all about his encounter with Mr. Talley. He had been nursing the
comfortable assurance that all he had to do was to deny. Now his house
of cards had come tumbling about his ears. Mr. Talley was a respected
citizen, and his word would be accepted by everybody.

Joe saw the effect of his remark and smiled drily.

"Want to revise that statement of yours that you weren't downtown at all
last night?" he asked, with affected politeness.

"He--he was mistaken," stammered Buck weakly, as he walked away,
followed by his discomfited cronies.

"I guess that will hold him for a while," chuckled Jimmy, as the radio
boys watched his retreating figure.

Two or three days passed without special developments. The broken pane
of glass had been restored and the parents of the boys had been formally
notified by the insurance company that they would be held responsible
jointly for the damages. A similar notice had been sent to the fathers
of Buck and his mates.

Mr. Looker replied, denying that his son was at all implicated in the
matter and refusing to pay. Mr. Layton admitted that his son had been
throwing snowballs in front of the store on the night in question, but
he stated that he had not thrown the ball with a stone in it that broke
the window. He added that any further communication regarding the matter
could be sent to his lawyer.

Of the others involved, some had taken similar positions and others had
ignored the matter altogether, leaving it to the insurance company to
make the next move. And there for the time the matter rested.

The radio boys had missed Larry's performance on the night that he had
opened with his new repertoire, but they were bound not to be cheated of
the second, which took place only a few nights later.

They crowded eagerly about the radio set when their friend's turn was
announced, and listened with a breathless interest, that was intensified
by their warm personal regard for the performer, to the rendition of the
cries of various animals with which Larry regaled them.

The imitations were so lifelike that the boys might well have imagined
they were in a zoölogical garden. Lions, tigers, bears, elephants,
snakes, moose, and other specimens of the animal and the reptile tribes
were imitated with a fidelity that was amazing. In addition, the
renditions were interspersed with droll and lively comments by Larry
that added immensely to the humor of the performance. When at last it
was over, the boys broke out into enthusiastic hand-clapping that would
have warmed Larry's heart, had he been able to hear it.

"The old boy is all there!" chortled Bob enthusiastically.

"He's a wonder!" ejaculated Joe. "No question there of a square peg in a
round hole. He's found exactly the work in life he's specially fitted
for."

"And think of the audience he has," put in Jimmy. "At this very minute
there are probably hundreds of thousands of people who have been tickled
to death at his performance. Just suppose those people all clapped their
hands at once just as we have done and we could hear it. Why, it would
be like a young earthquake."

At this moment the doorbell rang, and Dr. Dale was announced. He spent a
few minutes with Mr. and Mrs. Layton, and then came up to have a little
chat with the boys. This was one thing he never overlooked. His interest
in and sympathy with the young were unbounded, and accounted largely for
the influence that he exerted in the community.

The radio boys greeted the minister warmly and gladly made room for him
around the table. His coming was never felt by them to be an
interruption. They regarded him almost as one of themselves. Apart, too,
from the thorough liking they had for him as a man, they were
exceedingly grateful to him for the help he had been to them in radio
matters. He was their mentor, guide and friend.

"I knew I'd find you busy with the radio," he said, with a genial smile.

"We can't be torn away from it," replied Bob. "We think it's just the
greatest thing that ever happened. Just now we've been listening to
Larry Bartlett give his imitations of animals. You remember Larry?"

"I certainly do," replied Dr. Dale. "And I remember how you boys helped
him get his present position. It was one of the best things you ever
did. He's certainly a finished artist. I heard him on his opening night,
and I've laughed thinking of it many times since. He's a most amusing
entertainer."

It was the first opportunity the boys had had to tell the doctor of the
night when Bob found that he was a human aerial, and he listened to the
many details of the experiment with absorbed interest.

"It's something new to me," he said. "You boys have reason to be
gratified at having had a novel experience. That's the beauty of radio.
Something new is always cropping up. Many of the other sciences have
been more or less fully explored, and while none of them will ever be
exhausted, their limits have been to some extent indicated. But in radio
we're standing just on the threshold of a science whose infinite
possibilities have not even been guessed. One discovery crowds so
closely on the heels of another that we have all we can do to keep track
of them.

"I've just got back from a little trip up in New York State," he went
on, as he settled himself more comfortably in his chair, "and I stopped
off at Schenectady to look over the big radio station there. By great
good luck, Marconi happened to be there on the same day----"

"Marconi!" breathed Bob. "The father of wireless!"

"Yes," smiled Dr. Dale. "Or if you want to put it in another way, the
Christopher Columbus who discovered the New World of radio. I counted it
a special privilege to get a glimpse of him. But what attracted my
special attention in the little while I could spend there was a small
tube about eighteen inches long and two inches in diameter which many
radio experts think will completely revolutionize long distance radio
communication."

"You mean the Langmuir tube," said Joe. "I was reading of it the other
day, and it seems to be a dandy."

"It's a wonderful thing," replied the doctor. "Likely enough it will
take the place of the great transatlantic plants which require so much
room and such enormous machinery. It's practically noiseless. Direct
current is sent into the wire through a complicated wire system and
generates a high frequency current of tremendous power. I saw it working
when it was connected with an apparatus carrying about fifteen thousand
volts of electricity in a direct current. A small blue flame shot
through the tube with scarcely a particle of noise. The broken impulse
from the electrical generators behind the tube was sent through the tube
to be flung off from the antenna into space in the dots and dashes of
the international code. That little tube was not much bigger than a
stick of dynamite, but was infinitely more powerful. I was so fascinated
by it and all that it meant that it was hard work to tear myself away
from it. It marks a great step forward in the field of radio."

"It must have been wonderfully interesting," remarked Bob. "And yet I
suppose that in a year or two something new will be invented that will
put even that out of date."

"It's practically certain that there will be," assented the doctor. "The
miracles of to-day become the commonplaces of to-morrow. That
fifty-kilowatt tube that develops twelve horsepower within its narrow
walls of glass, wonderful as it is, is bound to be superseded by
something better, and the inventor himself would be the first one to
admit it. Some of the finest scientific brains in the country are
working on the problem, and he would be a bold prophet and probably a
false prophet that would set any bounds to its possibilities.

"Radio is yet in its infancy," the doctor concluded, as he rose to go.
"But one thing is certain. In the lifetime of those who witnessed its
birth it will become a giant--but a benevolent giant who, instead of
destroying will re-create our civilization."

CHAPTER VI

THE FOREST RANGER

Some days later Bob and Herb and Joe were on their way to Bob's house to
do a little experimenting on the latter's set, when they were surprised
at the alacrity with which Jimmy turned a corner and came puffing up to
them.

"Say, fellows!" he yelled, as he came within earshot, "I've got some
mighty interesting news for you."

"Let's have it," said Bob.

"It's about the snowball Buck fired through the window," panted Jimmy,
falling into step beside them. "I met a man who's staying up at the
Sterling House. He says Buck's the boy who did it, all right."

"How does he know?" all of the others asked with interest.

"Saw Buck pick up a stone and pack the snow hard around it," said Jimmy
importantly. "He saw it himself, so we've got one witness for our side,
all right."

"That's good," said Bob, adding, with a glint in his eye: "Say, wouldn't
I like to get my hands on Buck, just for about five minutes!"

"Well, you won't have a chance," said Jimmy, enjoying being the bearer
of so much news. "Buck's gone with his father to a lumber camp up in
Braxton woods."

"How do you know all this?" inquired Herb curiously. "You seem to be
chock full of information to-day."

"Oh, a little bird told me," said Jimmy, looking mysterious. However, as
Herb made a threatening motion toward him, he hurried to explain. "I met
Terry Mooney," he said. "I told him I knew all about who put the stone
in the snowball and I told him that our crowd was going to make his look
like two cents. He laughed and said swell chance we'd have. Said Buck
had gone to the lumber camp with his father and that he and Carl Lutz
were going to join him in a day or two. Just like Buck to run away when
he knows there's a good licking coming to him!" added Jimmy, with a
sneer.

"Oh, well, what do we care?" said Joe. "At least we sha'n't have those
fellows around spoiling all the fun."

"I'm glad you found out about the snowball just the same," said Bob
thoughtfully. "Every little bit helps when we have to fight against that
crooked gang of Buck's."

"Here's hoping," said Herb fervently, "that they stay away all the rest
of the spring."

By this time the lads had reached Bob's house. It was Saturday
afternoon, and as the boys crowded noisily into the hall Bob noticed
that his father was in the library and that he seemed to have company.

He was starting upstairs with the other lads when his father came out of
the library and called to him.

"Come on in for a few minutes, boys," he said. "I have a friend here who
is a man after your own hearts," and his eyes twinkled. "He's interested
in radio."

The boys needed no second invitation, for they never missed an
opportunity of meeting any one who could tell them something about the
wonders of radio.

Mr. Layton's guest was lounging in one of the great chairs in the
library, and from the moment the boys laid eyes on him they knew they
were going to hear something of more than usual interest.

The stranger was big, over six feet, and his face and hands were like a
Cuban's, they were so dark. Even his fair hair seemed to have been burnt
a darker hue by the sun. There was a tang of the great out-of-doors
about him, a hint of open spaces and adventure that fascinated the radio
boys.

"This is my son, Mr. Bentley," said Mr. Layton to the lounging stranger,
still with a twinkle in his eye. "And the other boys are his inseparable
companions. Also I think they are almost as crazy about radio as you
are."

The stranger laughed and turned to Bob.

"I've been upstairs to see your set," he said, adding heartily: "It's
fine. I've seldom seen better amateur equipment."

If Bob had liked this stranger before, it was nothing to what he felt
for him now. To the radio boys, if any one praised their radio sets,
this person, no matter who it was, promptly became their friend for
life.

"I'm glad you think it's pretty good," Bob said modestly. "We fellows
have surely worked hard enough over it."

"This gentleman here," said Mr. Layton to the boys, "ought to know quite
a bit about radio. He operates an airplane in the service of our
Government Forestry."

"In the United States Forest Service?" cried Bob, breathlessly, eyeing
the stranger with increasing interest. "And is your airplane equipped
with radio?"

"Very much so," replied Mr. Bentley. "It seems almost a fairy tale--what
radio has done for the Forest Service."

"I've read a lot about the fighting of forest fires," broke in Joe
eagerly. "But I didn't know radio had anything to do with it."

"It hadn't until the last few years," the visitor answered, adding, with
a laugh: "But now it's pretty near the whole service!"

"Won't you tell us something about what you do?" asked Bob.

Mr. Bentley waved a deprecating hand while Mr. Layton leaned back in his
chair with the air of one who is enjoying himself.

"It isn't so much what I do," protested this interesting newcomer, while
the boys hung upon his every word. "It is what radio has done in the
fighting of forest fires that is the marvelous, the almost unbelievable,
thing. The man who first conceived the idea of bringing radio into the
wilderness had to meet and overcome the same discouragements that fall
to the lot of every pioneer.

"The government declared that the cost of carrying and setting up the
radio apparatus would be greater than the loss occasioned every season
by the terribly destructive forest fires. But there was a fellow named
Adams who thought he knew better."

"Adams!" repeated Bob breathlessly. "Wasn't he the fellow who had charge
of the Mud Creek ranger station at Montana?"

The visitor nodded and gazed at Bob with interest. "How did you know?"
he asked.

"Oh, I read something about him a while ago," answered Bob vaguely. He
was chiefly interested in having Mr. Bentley go on.

"I should think," said Herb, "that it would be pretty hard work carrying
delicate radio apparatus into the lumber country."

"You bet your life it is," replied Mr. Bentley. "The only way the
apparatus can be carried is by means of pack horses, and as each horse
can't carry more than a hundred and fifty pounds you see it takes quite
a few of the animals to lug even an ordinary amount of apparatus.

"The hardest part of the whole thing," he went on, warming to his
recital as the boys were so evidently interested, "was packing the
cumbersome storage batteries. These batteries were often lost in
transit, too. If a pack horse happened to slip from the trail, its pack
became loosened and went tumbling down the mountain side----"

"That's the life!" interrupted Jimmy gleefully, and the visitor smiled
at him.

"You might not think so if you happened to be the one detailed to travel
back over the almost impassable trails for the missing apparatus,"
observed Mr. Bentley ruefully. "It wasn't all fun, that pioneer
installation of radio. Not by any means."

"But radio turned the trick just the same," said Bob slangily. "I've
read that a message that used to take two days to pass between ranger
stations can be sent now in a few seconds."

"Right!" exclaimed Mr. Bentley, his eyes glinting. "In a little while
the saving in the cost of forest fires will more than pay for the
installation of radio. We nose out a fire and send word by wireless to
the nearest station, before the fire fairly knows it's started."

"But just what is it that you do?" asked Joe, with flattering eagerness.

"I do scout work," was the reply. "I help patrol the fire line in cases
of bad fires. The men fighting the fire generally carry a portable
receiving apparatus along with them, and by that means, I, in my
airplane, can report the progress of a fire and direct the distribution
of the men."

"It must be exciting work," said Herb enviously. "That's just the kind
of life I'd like--plenty of adventure, something doing every minute."

"There's usually plenty doing," agreed Mr. Bentley, with a likable grin.
"We can't complain that our life is slow."

"I should think," said Bob slowly, "that it might be dangerous,
installing sets right there in the heavy timber."

"That's what lots of radio engineers thought also," agreed Mr. Bentley.
"But no such trouble has developed so far, and I guess it isn't likely
to now."

"Didn't they have some trouble in getting power enough for their sets?"
asked Joe, with interest.

"Yes, that was a serious drawback in the beginning," came the answer.
"They had to design a special equipment--a sort of gasoline charging
plant. In this way they were able to secure enough power for the
charging of the storage batteries."

Bob drew a long breath.

"Wouldn't I have liked to be the one to fit up that first wireless
station!" he cried enthusiastically. "Just think how that Mr. Adams must
have felt when he received his first message through the air."

"It wasn't all fun," the interesting visitor reminded the boys. "The
station was of the crudest sort, you know. The first operator had a box
to sit on and another box served as the support for his apparatus."

"So much the better," retorted Bob stoutly. "A radio fan doesn't know or
care, half the time, what he's sitting on."

"Which proves," said Mr. Bentley, laughing, "that you are a real one!"
And at this all the lads grinned.

"But say," interrupted Joe, going back to the problem of power, "weren't
the engineers able to think up something to take the place of the
gasoline charging stations?"

"Oh, yes. But not without a good deal of experimenting. Now they are
using two hundred and seventy number two Burgess dry batteries. These,
connecting in series, secure the required three hundred and fifty-volt
plate current."

CHAPTER VII

RADIO AND THE FIRE FIEND

"Well, I hope that the boys know what you're talking about," interrupted
Mr. Layton at this point, his eyes twinkling, "for I'm sure I don't."

"They know what I'm talking about all right," returned his guest,
admiration in his laughing eyes as he looked at the boys. "Unless I miss
my guess, these fellows are the stuff of which radio experts are made. I
bet they'll do great things yet."

"Won't you tell us more about your experiences?" begged Herb, while the
other boys tried not to look too pleased at the praise. "It isn't often
we have a chance to hear of adventures like yours first hand."

"Well," said Mr. Bentley, modestly, "I don't know that there's much to
tell. All we scouts do is to patrol the country and watch for fires. Of
course, in case of a big fire, our duties are more exciting. I remember
one fire," he leaned back in his chair reminiscently and the boys
listened eagerly, hanging on every word. "It was a beauty of its kind,
covering pretty nearly fourteen miles. Thousands of dollars' worth of
valuable timber was menaced. It looked for a time as if it would get the
better of us, at that.

"Men were scarce and there was a high wind to urge the fire on. A
receiving set was rushed to the fire line, some of the apparatus in a
truck and some carried by truck horses. My plane was detailed to patrol
the fire line and give directions to the men who were fighting the
fire."

He paused, and the boys waited impatiently for him to go on.

"The good old plane was equipped for both sending and receiving, and I
tell you we patrolled that fourteen miles of flaming forest, sometimes
coming so close to the tree tops that we almost seemed to brush them.

"My duty, of course, was to report the progress of the fire. Controlled
at one point, it broke out at another, and it was through the messages
from my 'plane to the ground set stationed just behind the fire line
that the men were moved from one danger point to the next.

"Finally, the fire seeming nearly out along one side of the ridge, I
sent the men to fighting it on the other side, where it had been left to
rage uncontrolled. No sooner had the men scattered for the danger point
than the brooding fire broke out again and it was necessary to recall
half the men.

"It was a long fight and a hard one, but with the aid of the blessed old
wireless, we finally won out. As a matter of fact, the wireless-equipped
airplane has become as necessary to the Forest Service as ships are to
the navy.

"In the old days," he went on, seeing that the boys were still deeply
interested, "when they depended upon the ordinary telephone to convey
warnings of fires they were surely leaning upon a broken reed.

"Often, just when they needed the means of communication most, the fire
would sweep through the woods, destroying trees to which the telephone
wires were fastened, and melting the wires themselves. So the eyes of
the Forest Service were put out and they were forced to work in the
dark."

"But I should think," protested Bob, "that there would be times when
even wireless would be put out of the job. Suppose the fire were to
reach one of the stations equipped with wireless. What then?"

Mr. Bentley laughed as though amused at something.

"I can tell you an interesting incident connected with that," he said.
"And one that shows the pluck and common sense of radio operators in
general--don't think that I'm throwing bouquets at myself, now, for
first and last, I am a pilot, even if sometimes I find it necessary to
employ radio.

"Well, anyway, this operator that I am speaking of, found himself in a
perilous position. A fire had been raging for days, and now it was so
close to his station that the station itself was threatened.

"One morning when he got up the smoke from the burning forest was
swirling about the open space in front of the station and he knew that
before long he would be seeing flame instead of smoke. The fire fighters
had been working ceaselessly, fighting gallantly, but the elements were
against them. The air was almost as dry and brittle as the wood which
the flames lapped up and there was a steady wind that drove the fire on
and on.

"If only there might come a fog or the wind change its direction! But
the radio man had no intention of waiting on the elements. I don't
believe he gave more than a passing thought to his own safety--his chief
interest was for the safety of his beloved apparatus.

"He decided to dismantle the set, build a raft and set himself and the
apparatus adrift upon the water in the attempt to save it.

"And so he worked feverishly, while the fire came closer and he could
hear the men who were fighting the fire shouting to each other. Finally
he succeeded in dismantling the set and got it down to the water's edge.

"Here he built a rough raft, piled the apparatus upon it, jumped after
it, and drifted out into the middle of the lake."

"Did the station burn down?" asked Jimmy excitedly.

"No, fortunately. The wind died down in the nick of time, giving the men
a chance to control the blaze. When it was evident the danger was past,
the operator set up his apparatus again and prepared to continue his
duties, as though nothing had happened.

"There you have the tremendous advantage of radio. There were no wires
to be destroyed. Only a radio set which could be dismantled and taken to
safety while the fire raged."

"That operator sure had his nerve with him, all right," said Bob
admiringly.

"More nerve than common sense perhaps," chuckled Mr. Bentley. "But you
certainly can't help admiring him. He was right there when it came to
grit."

After a while they began to discuss technicalities, and the boys learned
a great many things they had never known before. The pilot happening to
mention that there were sometimes a number of airplanes equipped with
radio operating within a restricted district, Joe wanted to know if they
did not have a good deal of trouble with interference.

"No. There was at first some interference by amateurs, but these soon
learned to refrain from using their instruments during patrol periods.

"You see," he explained, "we use a special type of transmitting outfit
aboard our fire-detection craft. It's called the SCR-Seventy-three. The
equipment obtains its power from a self-excited inductor type
alternator. This is propelled by a fixed wooden-blade air fan. In the
steam-line casing of the alternator the rotary spark gap, alternator,
potential transformer, condenser and oscillation transformer are
self-contained. Usually the alternator is mounted on the underside of
the fuselage where the propeller spends its force in the form of an air
stream. The telegraph sending keys, field and battery switch, dry
battery, variometer and antenna reel are the only units included inside
the fuselage.

"The type of transmitter is a simple rotary gap, indirectly excited
spark and provided with nine taps on the inductance coil of the closed
oscillating circuit. Five varying toothed discs for the rotary spark gap
yield five different signal tones and nine different wave lengths are
possible.

"So," he finished, looking around at their absorbed faces, "you see it
is quite possible to press into service a number of airplanes without
being bothered by interference."

"It sounds complete," said Bob. "I'd like a chance to see one of those
sets at close range sometime."

The time passed so quickly that finally the visitor rose with an apology
for staying so late. The radio boys were sorry to see him go. They could
have sat for hours more, listening to him.

"That fellow sure has had some experiences!" said Joe, as, a little
later, the boys mounted the stairs to Bob's room. "It was mighty lucky
we happened along while he was here."

"You bet your life," said Herb. "I wouldn't have missed meeting him for
a lot."

"Say, fellows," Jimmy announced from the head of the stairs, "I know now
what I'm going to do when I'm through school. It's me for the tall
timber. I'm going to pilot an airplane in the service of my country."

"Ain't he noble?" demanded Herb, grinning, as the boys crowded into
Bob's room.

CHAPTER VIII

NEAR DISASTER

Several days later while the radio boys were experimenting with their
big set and talking over their interesting meeting with the Forest
Service ranger, Herb displayed an immense horseshoe magnet.

"Look what he's got for luck," chortled Jimmy. "The superstitious nut!"

"Superstitious nothing!" snorted Herb. "If I'd wanted it for luck I
wouldn't have got a magnet, would I? Any old common horseshoe would have
done for luck."

"Well, what's the big idea?" asked Bob, looking up from the audion tube
he was experimenting with. "Or is there any?" he added, with a grin.

"You bet your life there is!" returned Herb. "It's got to do with that
very audion tube you're fussing with."

"Ah, go on," jeered Joe, good-naturedly. "What's a magnet got to do with
an audion tube, I'd like to know!"

"Poor old Herb," added Jimmy, with a commiserating shake of the head.

"Say, look here, all you fellows! Don't you go wasting any pity on me,"
cried Herb hotly. "If you don't look out, I won't show you my experiment
at all."

"Go on, Herb," said Bob consolingly. "I'm listening."

"Well, I'm glad there's one sensible member of this bunch!" cried Herb,
and from then on addressed himself solely to Bob. "Look here," he said.
"You can make the audion tube ever so much more sensitive to vibration
if you put this magnet near it."

"Who says so?" asked Bob, with interest.

"I do. Here, put on the headphones and listen. I'll prove it to you."

Bob obeyed and tuned in to the nearest broadcasting station where a
concert was scheduled. As soon as he signified by a nod of his head that
the connection was satisfactory Herb placed the big horseshoe magnet in
such a position that the poles of the magnet were on each side of the
tube.

Sure enough, Bob was amazed at the almost magical improvement in the
sound. It was clearer, more distinct, altogether more satisfactory. He
listened in for another moment then wonderingly took off the headphones
while Herb grinned at him in triumph.

"Well, what do you think?" asked the latter while Joe and Jimmy looked
at them curiously.

"Think?" repeated Bob, still wonderingly. "Why, there's only one thing
to think, of course. That fool horseshoe of yours, Herb, is one
wonderful improvement. I don't know how it works, but it surely is a
marvel."

Herb glanced at Jimmy and Joe in triumph.

"What did I tell you?" he said. "Perhaps now you'll believe that my idea
wasn't such a fool one after all."

"But what did it do, Bob?" asked Joe, mystified.

"It increased the sensitivity of that old audion tube, that's what it
did," replied Bob, absently, his mind already busy with inventive
thoughts. "I can't see yet just how it accomplished it, but the
connection with the station was certainly clearer and more distinct than
usual."

"But how can a magnet increase the sensitivity of a vacuum tube?" asked
Jimmy, not yet wholly convinced. "It doesn't make sense."

"Well, I don't see why not," contradicted Joe slowly. "I suppose the
improvement is due to the magnetic effect of the magnet upon the
electrons flowing from the filament to the plate. I don't exactly see
why it should be an improvement, but if it is, then there must be some
reason for it."

"I wish we could find the reason!" cried Bob excitedly. "If we could
make some improvement upon the vacuum tube----"

"Don't wake him up, he is dreaming!" cried Herb. "If you don't look out,
old boy, you'll have us all millionaires."

"Well, there are worse things," retorted Bob, taking the magnet from
Herb's hand and placing it near the tube. "This has given us something
to think about, anyway."

For a while they puzzled over the mystery, trying to find some way in
which the discovery might be made to serve a practical purpose--all
except Herb, who retired to one corner of the "lab" to fuss with some
chemicals which he fondly hoped might be used in the construction of a
battery.

So engrossed were the boys in the problem of the magnet and vacuum tube
that they forgot all about Herb and his experiments. So what happened
took them completely off their guard.

There was a sudden cry from Herb, followed closely by an explosion that
knocked them off their feet. For a moment they lay there, a bit dazed by
the shock. Then they scrambled to their feet and looked about them.
Herb, being the nearest to the explosion, had got the worst of it. His
face and hands were black and he was shaking a little from the shock. He
gazed at the boys sheepishly.

"Wh-what happened?" asked Jimmy dazedly.

"An earthquake, I guess," replied Bob, as he looked about him to see
what damage had been done.

Some doughnuts, which their namesake had recently fetched from the
store, lay scattered upon the floor, together with some rather
dilapidated-looking pieces of candy, but aside from this, nothing seemed
to have been damaged seriously.

Jimmy's followed Bob's gaze, and, finding his precious sweets upon the
floor, began gathering them up hastily, stuffing a doughnut in his mouth
to help him hurry. What mattered it to Jimmy that the floor was none too
clean?

"Say, what's the big idea, anyway," Joe demanded of the blackened Herb.
"Trying to start a Fourth of July celebration, or something?"

"I was just mixing some chemicals, and the result was a flare-up,"
explained Herb sulkily. "Now, stop rubbing it into a fellow, will you?
You might know I didn't do it on purpose."

Bob began to laugh.

"Better get in connection with some soap and water, Herb," he said.
"Just now you look like the lead for a minstrel show."

"Never mind, Herb," Joe flung after the disconsolate scientist as he
made for the door. "As long as you don't hurt anything but Jimmy's
doughnuts, we don't care. You can have as many explosions as you like."

"Humph, that's all right for you," retorted Jimmy. "But I'll have you
know I spent my last nickel for those doughnuts."

"Just the same," said Bob soberly, as they returned to the problem of
the vacuum tube, "we're mighty lucky to have come off with so little
damage. Mixing chemicals is a pretty dangerous business unless you know
just what you're doing."

"And even then it is," added Joe.

CHAPTER IX

A HAPPY INSPIRATION

The days passed by, the boys becoming more and more engrossed in the
fascination of radio all the time. They continued to work on their sets,
sometimes with the most gratifying results, at others seeming to make
little headway.

But in spite of occasional discouragements they worked on, cheered by
the knowledge that they were making steady, if sometimes slow, progress.

There were so many really worth-while improvements being perfected each
day that they really found it difficult to keep up with them all.

"Wish we could hear Cassey's voice again," said Herb, one day when they
had tuned in on several more or less interesting personal messages.

"I don't know what good it would do us," grumbled Joe. "If he speaks
always in code he could keep us guessing till doomsday."

"He's up to some sort of mischief, anyway," said Bob; "and I, for one,
would enjoy catching him at it again."

"We would be more comfortable to have Dan Cassey in jail, where he
belongs," observed Jimmy.

But just at present the trailing of that stuttering voice seemed an
impossible feat even for the radio boys. If they could only get some
tangible clue to work on!

They saw nothing of Buck Looker or his cronies about town, and concluded
that they were still at the lumber camp.

"Can't stay away too long to suit me," Bob said cheerfully.

It was about that time that Bob found out about Adam McNulty. Adam
McNulty was the blind father of the washerwoman who served the four
families of the boys.

Bob went to the McNulty cabin, buried in the most squalid district of
the town, bearing a message from his mother. When he got there he found
that Mr. McNulty was the only one at home.

The old fellow, smoking a black pipe in the bare kitchen of the house,
seemed so pathetically glad to see some one--or, rather, to hear some
one--that Bob yielded to his invitation to sit down and talk to him.

And, someway, even after Bob reached home, he could not shake off the
memory of the lonesome old blind man with nothing to do all day long but
sit in a chair smoking his pipe, waiting for some chance word from a
passer-by.

It did not seem fair that he, Bob, should have all the good things of
life while that old man should have nothing--nothing, at all.

He spoke to his chums about it, but, though they were sympathetic, they
did not see anything they could do.

"We can't give him back his eyesight, you know," said Joe absently,
already deep in a new scheme of improvement for the set.

"No," said Bob. "But we might give him something that would do nearly as
well."

"What do you mean?" they asked, puzzled.

"Radio," said Bob, and laid his hand lovingly on the apparatus. "If it
means a lot to us, just think how much more it would mean to some one
who hasn't a thing to do all day but sit and think. Why, I don't suppose
any of us who can see can begin to realize what it would mean not to be
able even to read the daily newspaper."

The others stared at Bob, and slowly his meaning sank home.

"I get you," said Joe slowly. "And say, let me tell you, it's a great
idea, Bob. It wouldn't be so bad to be blind if you could have the daily
news read to you every day----"

"And listen to the latest on crops," added Jimmy.

"To say nothing of the latest jazz," finished Herb, with a grin.

"Well, why doesn't this blind man get himself a set?" asked Jimmy
practically. "I should think every blind person in the country would
want to own one."

"I suppose every one of them does," said Bob. "And Doctor Dale said the
other day that he thought the time would come when charities for the
blind would install radio as a matter of humanity, and that prices of
individual sets would be so low that all the blind could afford them.
The blind are many of them old, you know, and pretty poor."

"You mean," said Herb slowly, "that most of the blind folks who really
need radio more than anybody else can't afford it? Say, that doesn't
seem fair, does it?"

"It isn't fair!" cried Bob, adding, eagerly: "I tell you what I thought
we could do. There's that old set of mine! It doesn't seem much to us
now, beside our big one, but I bet that McNulty would think it was a
gold mine."

"Hooray for Bob!" cried Herb irrepressibly. "Once in a while he really
does get a good idea in his head. When do we start installing this set
in the McNulty mansion, boys?"

"As soon as you like," answered Bob. "Tomorrow's Saturday, so we could
start early in the morning. It will probably take us some time to rig up
the antenna."

The boys were enthusiastic about the idea, and they wasted no time
putting it into execution. That very night they looked up the old set,
examining it to make sure it was in working order.

When they told their families what they proposed to do, their parents
were greatly pleased.

"It does my heart good," said Mr. Layton to his wife, after Bob had gone
up to bed, "to see that those boys are interested in making some one
besides themselves happy."

"They're going to make fine men, some day," answered Mrs. Layton softly.

The boys arrived at the McNulty cottage so early the next morning that
they met Maggie McNulty on her way to collect the day's wash.

When they told her what they were going to do she was at first too
astonished to speak and then threatened to fall upon their necks in her
gratitude.

"Shure, if ye can bring some sunshine into my poor old father's dark
life," she told them in her rich brogue, tears in her eyes, "then ye'll
shure win the undyin' gratitude uv Maggie McNulty."

It was a whole day's job, and the boys worked steadily, only stopping
long enough to rush home for a bit of lunch.

They had tried to explain what they were doing to Adam McNulty, but the
old man seemed almost childishly mystified. It was with a feeling of
dismay that the boys realized that, in all probability, this was the
first time the blind man had ever heard the word radio. It seemed
incredible to them that there could be anybody in the world who did not
know about radio.

However, if Adam McNulty was mystified, he was also delightedly,
pitifully excited. He followed the boys out to the cluttered back yard
where they were rigging up the aerial, listening eagerly to their
chatter and putting in a funny word now and then that made them roar
with laughter.

Bob brought him an empty soap box for a seat and there the old man sat
hour after hour, despite the fact that there was a chill in the air,
blissfully happy in their companionship. He had been made to understand
that something pleasant was being done for him, but it is doubtful if he
could have asked for any greater happiness than just to sit there with
somebody to talk to and crack his jokes with.

They were good jokes too, full of real Irish wit, and long before the
set was ready for action the boys had become fond of the old fellow.

"He's a dead game sport," Joe said to Bob, in that brief interval when
they had raced home for lunch. "I bet I'd be a regular old crab, blind
like that."

Mrs. Layton put up an appetizing lunch for the blind man, topping it off
with a delicious homemade lemon pie and a thermos bottle full of
steaming coffee.

The way the old man ate that food was amazing even to Jimmy. Maggie was
too busy earning enough to keep them alive to bother much with dainties.
At any rate, Adam ate the entire lemon pie, not leaving so much as a
crumb.

"I thought I was pretty good on feeding," whispered Joe, in a delighted
aside, "but I never could go that old bird. He's got me beat a mile."

"Well," said Jimmy complacently, "I bet I'd tie with him."

If the boys had wanted any reward for that day of strenuous work, they
would have had it when, placing the earphones upon his white head, they
watched the expression of McNulty's face change from mystification to
wonder, then to beatific enjoyment.

He listened motionless while the exquisite music flooded his starved old
soul. Toward the end he closed his eyes and tears trickled from beneath
the lids down his wrinkled face. He brushed them off impatiently and the
boys noticed that his hand was trembling.

It was a long, long time before he seemed to be aware that there was any
one in the room with him. He seemed to have completely forgotten the
boys who had bestowed this rare gift upon him.

After a while, coming out of his dream, the old man began fumbling with
the headphones as if he wanted to take them off, and Bob helped him. The
man tried to speak, but made hard work of it. Emotion choked him.

"Shure, an' I don't know what to make of it at all, at all," he said at
last, in a quivering voice. "Shure an' I thought the age of miracles was
passed. I'm only an ignorant old man, with no eyes at all; but you lads
have given me something that's near as good. Shure an' it's an old
sinner I am, for shure. Many's the day I've sat here, prayin' the Lord
would give me wan more minute o' sight before I died, an' it was
unanswered my prayers wuz, I thought. It's grateful I am to yez, lads.
It's old Adam McNulty's blessin' ye'll always have. An' now will yez put
them things in my ears? It's heaven's own angels I'd like to be hearin'
agin. That's the lad--ah!"

And while the beatific expression stole once more over his blind old
face the boys stole silently out.

CHAPTER X

THE ESCAPED CONVICT

The boys saw a good deal of Adam McNulty in the days that followed, and
the change in the old man was nothing short of miraculous.

He no longer sat in the bare kitchen rocking and smoking his pipe,
dependent upon some passer-by for his sole amusement. He had radio now,
and under the instruction of the boys he had become quite expert in
managing the apparatus. Although he had no eyes, his fingers were
extraordinarily sensitive and they soon learned to handle the set
intelligently.

His daughter Maggie, whose gratitude to the boys knew no bounds, looked
up the radio program in the paper each day and carefully instructed her
father as to just when the news reports were given out, the story
reading, concerts, and so forth.

And so the old blind man lived in a new world--or rather, the old world
which he had ceased to live in when he became blind--and he seemed
actually to grow younger day by day. For radio had become his eyes.

Doctor Dale heard of this act of kindness on the part of the boys and he
was warm in his praise.

"Radio," he told the boys one day when he met them on the street, "is a
wonderful thing for those of us that can see, but for the blind it is a
miracle. You boys have done an admirable thing in your kindness to Adam
McNulty, and I hope that, not only individuals, but the government
itself will see the possibilities of so great a charity and follow your
example."

The boys glowed with pride at the doctor's praise, and then and there
made the resolve that whenever they came across a blind person that
person should immediately possess a radio set if it lay within their
power to give it to him.

On this particular day when so many things happened the boys were
walking down Main Street, talking as usual of their sets and the
marvelous progress of radio.

Although it was still early spring, the air was as warm almost as it
would be two months later. There was a smell of damp earth and pushing
grass in the air, and the boys, sniffing hungrily, longed suddenly for
the freedom of the open country.

"Buck and his bunch have it all their own way," said Herb discontentedly.
"I wouldn't mind being up in a lumber camp myself just now."

"Too early for the country yet," said Jimmy philosophically. "Probably
be below zero to-morrow."

"What you thinking about, Bob?" asked Joe, noticing that his chum had
been quiet for some time.

"I was thinking," said Bob, coming out of his reverie, "of the
difference there has been in generators since the early days of
Marconi's spark coil. First we had the spark transmitters and then we
graduated to transformers----"

"And they still gave us the spark," added Joe, taking up the theme.
"Then came the rotary spark gap and later the Goldsmith generator----"

"And then," Jimmy continued cheerfully, "the Goldsmith generator was
knocked into a cocked hat by the Alexanderson generator."

"They'll have an improvement on that before long, too," prophesied Herb.

"They have already," Bob took him up quickly. "Don't you remember what
Doctor Dale told us of the new power vacuum tube where one tube can take
care of fifty K. W.?"

"Gee," breathed Herb admiringly, "I'll say that's some energy."

"Those same vacuum tubes are being built right now," went on Bob
enthusiastically. "They are made of quartz and are much cheaper than the
alternators we're using now."

"They are small too, compared to our present-day generators," added Joe.

"You bet!" agreed Bob, adding, as his eyes narrowed dreamily: "All the
apparatus seems to be growing smaller these days, anyway. I bet before
we fellows are twenty years older, engineers will have done away
altogether with large power plants and cumbersome machinery."

"I read the other day," said Joe, "that before long all the apparatus
needed, even for transatlantic stations, can be contained in a small
room about twenty-five feet by twenty-five."

"But what shall we do for power?" protested Herb. "We'll always have to
have generators."

"There isn't any such word as 'always' in radio," returned Bob. "I
shouldn't wonder if in the next twenty or thirty years we shall be able,
by means of appliances like this new power vacuum tube, to get our power
from the ordinary lighting circuit."

"And that would do away entirely with generators," added Joe
triumphantly.

"Well, I wouldn't say anything was impossible," said Herb doubtfully.
"But that seems to me like a pretty large order."

"It is a large order," agreed Bob, adding with conviction: "But it isn't
too large for radio to fill."

"Speaking of lodging all apparatus in one fair-sized room," Joe went on.
"I don't see why that can't really be done in a few years. Why, they say
that this new power vacuum tube which handles fifty K. W. is not any
larger than a desk drawer."

"I see the day of the vest-pocket radio set coming nearer and nearer,
according to you fellows," announced Herb. "Pretty soon we'll be getting
our apparatus so small we'll need a microscope to see it."

"Laugh if you want to," said Bob. "But I bet in the next few years we're
going to see greater things done in radio than have been accomplished
yet."

"And that's saying something!" exclaimed Joe, with a laugh.

"I guess," said Jimmy thoughtfully, "that there have been more changes
in a short time in radio than in any other science."

"I should say so!" Herb took him up. "Look at telephone and telegraph
and electric lighting systems. There have been changes in them, of
course, but beside the rapid-fire changes of radio, they seem to have
been standing still."

"There haven't been any changes to speak of in the electric lighting
systems for the last fifteen years or more," said Bob. "And the
telephone has stayed just about the same, too."

"There's no doubt about it," said Joe. "Radio has got 'em all beat as
far as a field for experiment is concerned. Say," he added fervently,
"aren't you glad you weren't born a hundred years ago?"

The boys stopped in at Adam McNulty's cabin to see how the old fellow
was getting along. They found him in the best of spirits and, after
"listening in" with him for a while and laughing at some of his Irish
jokes, they started toward home.

"I wish," said Bob, "that we could have gotten a line on Dan Cassey. It
seems strange that we haven't been able to pick up some real clue in all
this time."

For, although the boys had caught several other mysterious messages
uttered in the stuttering voice of Dan Cassey, they had not been able to
make head nor tail of them. The lads liked mysteries, but they liked
them chiefly for the fun of solving them. And they seemed no nearer to
solving this one than they had been in the beginning.

"I know it's a fool idea," said Herb sheepishly. "But since we were the
ones that got Cassey his jail sentence before, I kind of feel as if we
were responsible for him."

"It's pretty lucky for us we're not," remarked Joe. "We certainly would
be up against it."

On and on the boys went. Presently Joe began to whistle and all joined
in until suddenly Jimmy uttered a cry and went down on his face.

"Hello, what's wrong?" questioned Bob, leaping to his chum's side.

"Tripped on a tree root," growled Doughnuts, rising slowly. "Gosh! what
a spill I had."

"Better look where you are going," suggested Herb.

"I don't see why they can't chop off some of these roots, so it's better
walking."

"All right--you come down and do the chopping," returned Joe, lightly.

"Not much! The folks that own the woods can do that."

"Don't find fault, Jimmy. Remember, some of these very roots have
furnished us with shinny sticks."

"Well, not the one I tripped over."

It was some time later that the boys noticed that they had tramped
further than they had intended. They were on the very outskirts of the
town, and before them the heavily-wooded region stretched invitingly.

Jimmy, who, on account of his plumpness, was not as good a hiker as the
other boys, was for turning back, but the other three wanted to go on.
And, being three against one, Jimmy had not the shadow of a chance of
getting his own way.

It was cool in the shadows of the woods, and the boys were reminded that
it was still early in the season. It was good to be in the woods, just
the same, and they tramped on for a long way before they finally decided
it was time to turn back.

They were just about to turn around when voices on the path ahead of
them made them hesitate. As they paused three men came into full view,
and the boys stood, staring.

Two of the men they had never seen before, but the other they knew well.
It was the man whose voice they had been trailing all these weeks--Dan
Cassey, the stutterer!

CHAPTER XI

DOWN THE TRAP DOOR

It seemed that in the semi-darkness of the woods Cassey did not at once
recognize the radio boys. He was talking excitedly to his companions in
his stuttering tongue and he was almost upon the boys before he realized
who they were.

He stopped still, eyes and mouth wide open. Then, with a stuttered
imprecation, he turned and fled. The men with him stayed not to
question, but darted furtively into the woods.

"Come on, fellows!" cried Bob, with a whoop of delight. "Here's where we
nail Dan Cassey, sure."

The boys, except poor Jimmy, were unusually fleet, and they soon
overtook Cassey. Bob's hand was almost upon him when the man doubled
suddenly in his tracks and darted off into the thick underbrush.

Bob, with Herb and Joe close at his heels, was after him in a minute. He
reached a clearing just in time to see Cassey dash into an old barn
which had been hidden by the trees.

The boys plunged into the barn with Jimmy pantingly bringing up the
rear. In Bob's heart was a wild exultation. They had Cassey cornered.
Once more they would bring this criminal to justice.

"You guard the door," he called in a low tone to Joe. "See that Cassey
doesn't get out that way, and Herb and I will get after him in here."

The barn was so dark that they could hardly see to move around. There
was a window high up in the side wall, but this was so covered with dirt
and cobwebs that it was almost as though there was none.

However, Cassey must be lurking in one of those dark corners, and if
they moved carefully they were sure to capture him!

There was a loft to the barn, but if there had been a ladder leading up
to it it had long since rotted and dropped away, so that Bob was
reasonably sure the man could not be up there.

It was eery business, groping about in the musty darkness of the old
barn for a man who would go to almost any lengths of villainy to keep
from being caught.

Suddenly Bob saw something move, and, with an exultant yell, jumped
toward it. Once more he almost had his hand upon Cassey when--something
happened.

The floor of the barn seemed to open and let him through, and his chums
with him. As he fell through the hole into blackness he had confused
thoughts of an earthquake. Then he struck bottom with a solid thump that
almost made him see stars.

He heard similar thumps about him and realized that Herb and Jimmy had
followed him. Whatever it was they had shot through had evidently
magically closed up again, for they were in absolute darkness.

"Well," came in a voice which Bob recognized as Jimmy's, "I must say,
this is a nice note!"

"We've been pushed off the end of the world, I guess," said Herb, with a
sorry attempt at humor. "Who all's in this party anyway? Are we all
here?"

"I guess so," said Joe, and at the sound of his voice Bob jumped.

"What are you doing here?" he asked. "I thought you were going to guard
the door."

"That's what I should have done, but I played the big idiot," retorted
Joe bitterly. "I couldn't resist coming after you fellows to be in on
the big fight. I suppose while I was trailing you boys somebody sneaked
in the door and signed our finish."

"Looks like it," said Bob, feeling himself to make sure there were no
bones broken. "And now, instead of delivering Cassey to justice we're
prisoners ourselves. Say, I bet the old boy isn't laughing at us or
anything just now."

"I'm awful sorry, Bob," said Joe penitently. "I thought if I kept my eye
on the door----"

"Oh, it's all right," said Bob generously. "Accidents will happen and
there's no use crying over spilled milk. I suppose the most sensible
thing for us to do right now is to hustle around and find a way out of
this place."

"Maybe there isn't any," said Jimmy dolefully. "Then what'll we do?"

"Stay here and let the rats eat us, I guess," said Herb cheerfully, and
Jimmy groaned.

"Gosh, don't talk about eating, old boy," he pleaded. "I'm just about
starved this minute."

"You'll probably stay starved for some little time longer," said Bob
unfeelingly. He had risen cautiously to his feet, and finding that their
prison was at least high enough for them to stand up in, reached his
hands tentatively above his head.

As, even by standing on tiptoe, his fingers encountered nothing but air,
he decided that they must have dropped further than he had thought at
the time.

A hand reached out and took hold of him and he realized that Joe was
standing beside him.

"Must have been some sort of trap door opening inward, I guess," said
the latter. "You didn't see anything, did you, Bob?"

"No. It happened too suddenly. One minute I was reaching forward to grab
hold of Cassey and the next moment I found myself flying through space."

"Humph," grunted Joe. "It was lucky for Cassey that we all happened to
be in a bunch," he said. "He couldn't have gotten rid of us so quickly
if we'd been scattered about----"

"As we should have been," added Bob. "Just the same," he added, after a
minute, "I don't suppose it would have done any good if one of us had
been left up there. It must have been the men who were with Cassey who
sprang the trap on us; and if that's so, the fight would have been three
to one."

"I'd like to have tried it just the same," said Joe belligerently. "I
bet Cassey would have got a black eye out of it, anyway."

For some time they groped around the black hole of their prison, hoping
to find some way of escape, but without success. They were beginning to
get tired and discouraged, and they sat down on the floor to talk the
situation over.

The queer thing about this hole in the ground was that it possessed a
flooring where one would have expected to find merely packed-down dirt.
The flooring consisted of rough boards laid side by side, and when the
boys moved upon it it sounded like the rattling of some rickety old
bridge.

"There's some mystery about this place," said Bob. "I bet this is a
regular meeting place for Cassey and whoever his confederates may be. In
case of pursuit all they would have to do would be to hide in this hole
and they'd be practically safe from discovery."

"I wonder," said Herb, "why Cassey didn't do that now."

"Probably didn't have time," said Bob. "I was right on his heels, you
know, and probably he didn't dare stop for anything."

"And so they turned the trick on us," said Joe. "And it sure was a neat
job."

"Too neat, if we don't get out of here soon," groaned Jimmy. "I bet
they've just left us here to starve!"

"I wouldn't put it beyond Cassey," said Herb gloomily. "It would be just
the kind of thing he'd love to do. He's got a grudge against us, anyway,
for doing him out of Miss Berwick's money and landing him in jail, and
this would be a fine way to get even."

"Well, if that's his game, he's got another guess coming," said Bob,
adding excitedly: "Say, fellows, if that was a trap door that let us
down into this hole, and it must have been something of that sort, we'll
probably be able to get out the same way."

"But it's above our heads," protested Herb.

"What difference does that make?" returned Bob impatiently. "One of us
can stand on the other's back, and we can haul the last fellow out by
his hands."

"Simple when you say it quick," said Joe gloomily. "But I bet that trap
door is bolted on the outside. You don't think Cassey's going to let us
off that easy, do you?"

"Well, we could see anyway," returned Bob. "Anything's better than just
sitting here. Come on, let's find that trap door."

This feat, in itself, was no easy one. They had wandered about in the
dark so much that they had become completely confused.

Since Herb was the slightest, he was hoisted up on Bob's shoulders and
they began the stumbling tour of their prison. It seemed ages before
Herb's glad cry announced a discovery of some sort.

"I've found a handle," he said. "Steady there, Bob, till I give it a
pull."

CHAPTER XII

GROPING IN DARKNESS

Herb tugged gently and gave another yell of delight when whatever was
attached to the handle yielded grudgingly to the pull.

"It's the trap door, fellows!" he cried. "Move over a bit, Bob, till I
pull the thing down."

Bob, who, about this time, was finding Herb's weight not any too
comfortable, moved over, and, in doing so, stumbled, nearly pitching
himself and Herb to the floor.

As it was, Herb lost his balance and leaped wildly. He landed on his
feet and reached out a hand to find Bob.

"Of all the tough luck," he groaned. "There I had the thing in my hand
and now we've gone and lost it again."

"Sorry. But stop your groaning and get busy," Bob commanded him. "I
haven't moved from this spot, so if you get up on my shoulders again you
ought to be able to get hold of the handle easily enough."

So, hoisted and pushed by Joe and Jimmy, Herb finally regained his perch
and felt for the handle. He found it, and this time pulled the door so
far open that the boys could see through the opening in the barn floor.

"If somebody can hold that door," panted Herb, "I think I can get
through this hole. Grab hold, boy. It sure is heavy."

So Joe caught the door as it swung downward and Herb scrambled through
the aperture. Bob gave a grunt of relief as the weight was taken from
his shoulders.

"You're next, Joe," Bob was saying when Jimmy came stumbling up,
carrying something that banged against Bob's legs.

"I've got it," he panted. "Had an idea I might find something like it.
Trust your Uncle Jimmy----"

"For the love of butter, what are you raving about?" interrupted Joe,
and Jimmy proudly exhibited his prize.

"A soap box," he said. "And a good big one, too. If we stand on that we
can reach the opening easily."

"Good for you, Doughnuts," cried Bob, joyfully seizing upon the soap
box. "This beats playing the human footstool all hollow. Jump up on it,
Jimmy, and see how quick you can get out of here."

Jimmy needed no second invitation. He scrambled up on the tall box, and
by stretching up on tip toe could just manage to get his fingers over
the edge of the flooring above.

"Give me a boost, some one," he commanded, and Bob obligingly
administered the boost.

Joe was next. Bob went last, holding the trap door with his foot to keep
it from closing too quickly. Once upon the floor of the barn he took his
foot away and the door banged to with a snap, being balanced by a rope
and weight above.

"Well, there's that!" exclaimed Bob, eyeing the closed door with
satisfaction. "If Cassey thought he was going to fool us long, he sure
was mistaken."

"Maybe he's hiding around here somewhere," suggested Herb, lowering his
voice to a whisper.

"No such luck," replied Bob. "I'd be willing to wager that the moment we
struck bottom there, Cassey and his friends beat it away from here as
fast as their legs could take them."

"Don't you think we'd better look around a little bit, anyway?"
suggested Joe.

"It wouldn't do any harm," agreed Bob. "But first let's have a look
outside. We don't want to overlook any clues."

The boys thrashed around the bushes about the barn until they were
satisfied no one was hiding there and then returned to the barn. They
were curious to find out just how they had been shot through that trap
door.

They thought at first that it was perhaps worked by some sort of
apparatus, but they found that this was not the case. They found by
experimenting that the trap door yielded easily to their weight, and
decided that it had been their combined rush upon Cassey that had done
the trick. The weight of the four of them upon it had shot the door down
so rapidly that they had not had time even to know what was happening to
them, much less scramble to safety. Then it had shut on them.

"It couldn't have worked better for them," said Herb, as they turned
toward the door of the barn. "I bet they're laughing yet at the way they
put things over."

"Let 'em laugh," said Bob, adding fiercely: "But I bet you anything that
the last laugh will be ours!"

"I wonder what Cassey was doing here, anyway," said Jimmy, as they
walked slowly homeward. "It was lucky, wasn't it, that we happened along
when we did?"

"I don't see where it's so lucky," grumbled Joe. "We're no nearer
catching him now than we ever were."

"Except that we know he's around this locality," put in Bob. "I guess
the police will be glad to know that."

"Oh! are you going to tell the police?" asked Jimmy, whose thoughts had
been upon what he was going to get for dinner.

"Of course," said Bob. "He's an escaped criminal, and it's up to us to
tell the police all we know about him."

"I only wish we knew more to tell," said Joe disconsolately.

Since they had been flung through the trap door, Joe had called himself
every unpleasant name he could think of for his carelessness. If he had
stayed at the door where he belonged, there would have been one of them
left to grapple with Dan Cassey. Probably the two men who had been with
Cassey when they had surprised him had not been anywhere around. They
belonged to the type of criminal that always thinks of its own safety
first. Probably they had not been anywhere near the barn. And if it had
been only Dan Cassey and himself, well, he, Joe, could at least have
given the scoundrel a black eye--maybe captured him.

He said something of this to his chums, but they laughed at him.

"Stop your grouching," said Bob. "Haven't we already agreed that there's
no use crying over spilled milk? And, anyway, you just watch out. We'll
get Cassey yet."

As soon as the boys reached town they went straight to the police
station and told the story of their encounter with Cassey to the
grizzled old chief, who nodded his head grimly and thanked them for the
information.

"I'll send some men out right away," he told them. "If there's a
criminal in those woods, they're sure to get him before dark. It's too
bad you lads couldn't have got him yourselves. It would sure have been a
feather in your caps!"

"Why doesn't he rub it in?" grumbled Joe, as they turned at last toward
home and dinner. "He ought to know we feel mad enough about it."

"Well," said Bob, "if the police round him up, because of our
information, it will be almost as good as though we'd caught him
ourselves. I wouldn't," he added, with a glint in his eye, "exactly like
to be in Cassey's shoes, now."

CHAPTER XIII

CUNNING SCOUNDRELS

But, contrary to the expectations of the radio boys, the police were not
able to locate Cassey nor any of the rest of the gang. They searched the
woods for miles around the old barn about which the boys had told them,
even carrying their search into the neighboring townships, but without
any result. It seemed as though the earth had opened and swallowed up
Cassey together with his rascally companions. If such a thing had
actually happened, their disappearance could not have been more
complete.

"They must be experts in the art of hiding," grumbled Bob, upon
returning from a visit to the chief of police. "I was certain they would
be rounded up before this."

"Guess they must have made a break for the tall timber," said Joe.

"Decided, maybe, it isn't just healthy around here," added Herb, with a
grin.

And then, just when they had decided that Cassey and his gang had made a
masterly getaway, the radio boys got on their trail once again.

That very evening, when tuning in for the concert, they caught another
of those mysterious, stuttering messages in the unmistakable voice of
Dan Cassey!

"Rice, rats, make hay," was the substance of this message, and the boys
would have laughed if they had not been so dumbfounded.

"What do you know about that?" gasped Jimmy. "That old boy sure has his
nerve with him."

"They're still hanging around here somewhere!" cried Bob excitedly.
"They've probably got a hiding place that even the police can't find."

"Oh, if we could only make sense of this!" exclaimed Herb, staring at
the apparently senseless message which he had written down. "If we only
had their code the whole thing would be simple."

"Oh, yes, if we only had a million dollars, we'd be millionaires!"
retorted Jimmy scornfully. "Where do you get that stuff, anyway?"

"Well," said Bob, temporarily giving up the problem, "as far as I can
see, all there is for us to do is to keep our eyes and ears open and
trust to luck. Now what do you say we listen in on the concert for a
little while?"

In the days that followed Cassey's voice came to them several times out
of the ether, and always in that same cryptic form that, try as they
would, they could not make out.

It was exasperating, that familiar voice coming to them out of the air
day after day without giving them the slightest clue to the whereabouts
of the speaker.

And then, while they were in town one day, they quite unexpectedly ran
into their old friend, Frank Brandon, the wireless inspector, whose work
for some time had taken him into another district.

However, he was to stay in Clintonia for a few days on business now, and
since he had nothing particular to do that day, Bob enthusiastically
invited him up to his home for a visit.

"Maybe you can give us some tips on our set," Bob added, as Mr. Brandon
readily accepted the invitation. "We're not altogether satisfied with
our batteries. For some reason or other they burn out too quickly."

"Yes, I'll take a look at it," agreed Mr. Brandon good-naturedly.
"Although I imagine you boys are such experts by this time I can't tell
you very much. What have you been doing with yourselves since we last
met?"

The boys told him something of their experiences, in which he showed
intense interest, and in return he told them some interesting things
that had happened to him.

And when he spoke of catching mysterious messages in the stuttering
voice of Dan Cassey, Bob broke in upon him eagerly.

"We've caught a good many such messages too," he said. "Have you managed
to make anything of them?"

"Not a thing," said Mr. Brandon, shaking his head. "If it is a criminal
code, and I am about assured that it is, then it is a remarkably clever
one and one that it is almost impossible to decipher without a key. I've
just about given up trying."

Then the boys told of their encounter with Cassey in the woods and their
adventure in the old barn, and Frank Brandon was immensely excited.

"By Jove," he said, "the man is up to his old tricks again! I'd like to
get hold of him before he does any serious harm. That sort of criminal
is a menace to the community.

"The funny part of it," he continued, as they turned the corner into
Bob's block, "is that these messages are not all in Cassey's voice. Have
you noticed that?"

It was the boys' turn to be surprised.

"That's a new one on us," Bob confessed. "The only messages we have
caught so far have been in Cassey's voice."

Frank Brandon slowly shook his head.

"No," he said, "I have caught a couple in a strange voice, a voice I
never heard before."

"The same kind of message?" asked Herb eagerly.

"The same kind of message," Brandon affirmed. "I have taken it for
granted that the owner of the strange voice is a confederate of
Cassey's."

"Maybe one of the fellows who was with him in the woods," said Jimmy,
and Mr. Brandon nodded gravely.

"It's possible," he said. "I don't know, of course, but I imagine that
there are several in Cassey's gang."

By this time they had reached Bob's home, and as it was nearly lunch
time, Mrs. Layton insisted that they all stay to lunch. The boys, not
liking to make her trouble, said they would go home and come back later,
but the lady of the house would have none of it.

"Sit down, all of you," she commanded, in her cheerful, hospitable way.
"I know you're starved--all but Jimmy--" this last with a smile, "and
there's plenty to eat."

Frank Brandon was very entertaining all during the meal and kept them in
gales of laughter. Mrs. Layton found him as amusing as did the boys.

At last the lunch came to an end and Mr. Brandon professed himself ready
to talk shop.

He was enthusiastic over the radio set the boys showed him and declared
that he could see very little improvement to suggest.

"You surely have kept up with the march," he said admiringly. "You have
pretty nearly all the latest appliances, haven't you? Good work, boys.
Keep it up and you'll be experts in earnest."

"If we could only find some way to lengthen the life of our storage
batteries," said Bob, not without a pardonable touch of pride, "we
wouldn't have much to complain about. But that battery does puzzle us."

"Keep your battery filled with water and see if it doesn't last you
about twice as long," suggested the radio expert. "Don't add any acid to
your battery, for it's only the water that evaporates."

"Will that really do the trick?" asked Joe, wondering. "I don't just see
how----"

"It does just the same," Brandon interrupted confidently. "All you have
to do is to try it to find out. Don't use ordinary water though. It
needs to be distilled."

"That's a new one on me, all right," said Bob, adding gratefully: "But
we're obliged for the information. If distilled water will lengthen the
life of our battery, then distilled water it shall have."

"It seems queer," said Mr. Brandon reflectively, "how apparently simple
things will work immense improvement. Marconi, for instance, by merely
shortening his wave length, is discovering wonderful things. We cannot
even begin to calculate what marvelous things are in store for us when
we begin to send out radio waves of a few centimeters, perhaps less. We