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.