MESSAGES INTO SPACE
Tom Swift's announcement of the practical completion of his wireless
plant brought hope to the discouraged hearts of the castaways. They
crowded about him, and asked all manner of questions.
Mr. Fenwick and Mr. Damon came in for their share of attention, for
Tom said had it not been for the aid of his friends he never could
have accomplished what he did. Then they all trooped up to the
little shack, and inspected the plant.
As the young inventor had said, it was necessarily crude, but when
he set the gasolene motor going, and the dynamo whizzed and hummed,
sending out great, violet-hued sparks, they were all convinced that
the young inventor had accomplished wonders, considering the
materials at his disposal.
"But it's going to be no easy task to rig up the sending and
receiving wires," declared Tom. "That will take some time."
"Have you got the wire?" asked Mr. Jenks.
"I took it from the stays of the airship," was Tom's reply, and he
recalled the day he was at that work, when the odd man had exhibited
the handful of what he said were diamonds. Tom wondered if they
really were, and he speculated as to what might be the secret of
Phantom Mountain, to which Mr. Jenks had referred.
But now followed a busy time for all. Under the direction of the
young inventor, they began to string the wires from the top of the
dead tree, to a smaller one, some distance away, using five wires,
set parallel, and attached to a wooden spreader, or stay. The wires
were then run to the dynamo, and the receiving coil, and the
necessary ground wires were installed.
"But I can't understand how you are going to do it," said Mrs.
Nestor. "I've read about wireless messages, but I can't get it
through my head. How is it done, Mr. Swift?"
"The theory is very simple," said the young inventor. "To send a
message by wire, over a telegraph system, a battery or dynamo is
used. This establishes a current over wires stretched between two
points. By means of what is called a 'key' this current is
interrupted, or broken, at certain intervals, making the sounding
instrument send out clicks. A short click is called a dot, and a
long click a dash. By combinations of dots, dashes, and spaces
between the dots and dashes, letters are spelled out. For instance,
a dot and a space and a dash, represent the letter 'A' and so on."
"I understand so far," admitted Mrs. Nestor.
"In telegraphing without wires," went on Tom, "the air is used in
place of a metallic conductor, with the help of the earth, which in
itself is a big magnet, or a battery, as you choose to regard it.
The earth helps to establish the connection between places where
there are no wires, when we 'ground' certain conductors."
"To send a wireless message a current is generated by a dynamo. The
current flows along until it gets to the ends of the sending wires,
which we have just strung. Then it leaps off into space, so to
speak, until it reaches the receiving wires, wherever they may be
erected. That is why any wireless receiving station, within a
certain radius, can catch any messages that may be flying through
the air--that is unless certain apparatus is tuned, or adjusted, to
prevent this."
"Well, once the impulses, or electric currents, are sent out into
space, all that is necessary to do is to break, or interrupt them at
certain intervals, to make dots, dashes and spaces. These make
corresponding clicks in the telephone receiver which the operator at
the receiving station wears on his ear. He hears the code of clicks,
and translates them into letters, the letters into words and the
words into sentences. That is how wireless messages are sent."
"And do you propose to send some that way?" asked Mrs. Anderson.
"I do," replied Tom, with a smile.
"Where to?" Mrs. Nestor wanted to know.
"That's what I can't tell," was Tom's reply. "I will have to project
them off into space, and trust to chance that some listening
wireless operator will 'pick them up,' as they call it, and send us
aid."
"But are wireless operators always listening?" asked Mr. Nestor.
"Somewhere, some of them are--I hope," was Tom's quiet answer. "As I
said, we will have to trust much to chance. But other people have
been saved by sending messages off into space; and why not we?
Sinking steamers have had their passengers taken off when the
operator called for help, merely by sending a message into space."
"But how can we tell them where to come for us--on this unknown
island?" inquired Mrs. Anderson.
"I fancy Captain Mentor can supply our longitude and latitude,"
answered Tom. "I will give that with every message I send out, and
help may come--some day."
"It can't come any too quick for me!" declared Mr. Damon. "Bless my
door knob, but my wife must be worrying about my absence!"
"What message for help will you send?" Captain Mentor wanted to
know.
"I am going to use the old call for aid," was the reply of the young
inventor. "I shall flash into space the three letters 'C.Q.D.' They
stand for 'Come Quick--Danger.' A new code call has been instituted
for them, but I am going to rely on the old one, as, in this part of
the world, the new one may not be so well understood. Then I will
follow that by giving our position in the ocean, as nearly as
Captain Mentor can figure it out. I will repeat this call at
intervals until we get help--"
"Or until the island sinks," added the scientist, grimly.
"Here! Don't mention that any more," ordered Mr. Hosbrook. "It's
getting on my nerves! We may be rescued before that awful calamity
overtakes us."
"I don't believe so," was Mr. Parker's reply, and he actually seemed
to derive pleasure from his gloomy prophecy.
"It's lucky you understand wireless telegraphy, Tom Swift," said Mr.
Nestor admiringly, and the other joined in praising the young
inventor, until, blushing, he hurried off to make some adjustments
to his apparatus.
"Can you compute our longitude and latitude, Captain Mentor," asked
the millionaire yacht owner.
"I think so," was the reply. "Not very accurately, of course, for
all my papers and instruments went down in the RESOLUTE. But near
enough for the purpose, I fancy. I'll get right to work at it, and
let Mr. Swift have it."
"I wish you would. The sooner we begin calling for help the better.
I never expected to be in such a predicament as this, but it is
wonderful how that young fellow worked out his plan of rescue. I
hope he succeeds."
It took some little time for the commander to figure their position,
and then it was only approximate. But at length he handed Tom a
piece of paper with the latitude and longitude written on it.
In the meanwhile, the young inventor had been connecting up his
apparatus. The wires were now all strung, and all that was necessary
was to start the motor and dynamo.
A curious throng gathered about the little shack as Tom announced
that he was about to flash into space the first message calling for
help. He took his place at the box, to which had been fastened the
apparatus for clicking off the Morse letters.
"Well, here we go," he said, with a smile.
His fingers clasped the rude key he had fashioned from bits of brass
and hard rubber. The motor was buzzing away, and the electric dynamo
was purring like some big cat.
Just as Tom opened the circuit, to send the current into the
instrument, there came an ominous rumbling of the earth.
"Another quake!" screamed Mrs. Anderson. But it was over in a
second, and calmness succeeded the incipient panic.
Suddenly, overhead, there sounded a queer crackling noise, a
vicious, snapping, as if from some invisible whips.
"Mercy! What's that?" cried Mrs. Nestor.
"The wireless," replied Tom, quietly. "I am going to send a message
for help, off into space. I hope some one receives it--and answers,"
he added, in a low tone.
The crackling increased. While they gathered about him, Tom Swift
pressed the key, making and breaking the current until he had sent
out from Earthquake Island the three letters--"C.Q.D." And he
followed them by giving their latitude and longitude. Over and over
again he flashed out this message.
Would it be answered? Would help come? If so, from where? And if so,
would it be in time? These were questions that the castaways asked
themselves. As for Tom, he sat at the key, clicking away, while,
overhead, from the wires fastened to the dead tree, flashed out the
messages.