The Electrical experimenter

May, 19 1 THE ELECTRICAL EXPERIMENTER 21
"Yes, if we can't stop them," he repeated
after me.
"Why, we won't be any better than the
rest 1)1 tlieni. That torpedo defense is
too good," I argued.
"Who said anything about torpedoes at
all?" he demanded, wheehng and staring
at me aggressively.
"Well, we're only a submarine,"
I retorted.
"Does that mean that
we necessarily have to use
^^^^^^^^
torpedoes?" he countered.
"Why, don't we?" I
asked.
"We haven't a thing
that resembles a torpedo
on this boat except the
shells for that three-inch
gun under the deck, and
they will be about as effective
against a battleship
as birdshot against an
elephant."
I stared
time then.
at him a long
He was seri-
^_____^_^_^
ous as I could see, even
in the starlight, but he was not lucid.
"Well, how are we going to get them
then ?" I asked, thinking that this natural
question was e.xpected of me.
"I'll show you," he answered, and
stept down the ladder leading below.
I made to follow.
"No, stay there," he commanded.
I did, leaning against the steel conning
tower. A moment later I heard the sound
of mechanism close to my head and glancing
up I saw something appear above the
conning tower. I climbed upon the low
rail and looked up to see what it was.
The steel plates had opened in the center
and from the opening had emerged
a hemispherical object, made of what appeared
to be very heavy glass and measuring
about three feet in diameter. Inside
it was what looked to be a small mechanical
device which seemed to run on a small
circular track.
I was busy examining the device when
I heard Parker beside me.
to
"That," he said, "Is the Feeler."
"The feeler?" I repeated, this was new
me.
"Ves, the feeler, a device that will lo,-ate
any ship within ten thousand yards, without
any part of our boat being seen."
I looked at the device again with increased
interest. I could not see anything
distinctive about it.
"Don't you see how
asked.
it works?" Parker
"X'o, I can't say that I do." I admitted.
"Come on down in the control room and
I'll show you."
He led the way down the ladder and
we went into the little bo.x of a room under
the conning tower where one is afraid to
lean against the wall for fear of starting
or stopping something necessary to the
life of the boat.
He picked out a glass case from araonjr the
litter of instruments on the walls and
pointed it out to me. It was not a very
big case. In it were three dials, an electric
lamp and
control wheels.
below it were three small
It looked very much like
the other dials and wheels so thick about
me, and was distinguished only by the
word "Feeler" on the case.
"This device," he said, "works on the
principle of electro-magnetic induction.
You know what that is, the setting up of
a current in something that cuts the field
,
of force caused by a magnet. Well, up
there in that glass case which will stand
any pressure the boat hull will, is a mag-
netic coil mounted on a revolving and inclined
carrier. This coil is shaped and
wound so that its lines of force are kept
within a very small area, in this case about
one and three tenths square feet Consequently
when a metal object passes thru
this relatively intense field, the induced
current in the metal object will be sufficient
XXZ E have publisht a great many stories in the past, but we do not
hesitate to state that "Eddy Currents" is one of the very cleverest
we have ever printed. Not only is it a rattling good story, but the scheme
is so plausible that we venture to prophesy that it will be actually tried
in the not too distant future. And then, the submarine will earn its
adjective "deadly" in the fullest sense of the term.
to make a difference in the load on the
coil. You see that don't you?"
I did. That was perfectly plain sailing,
electrically.
"Well then, when this load comes on,
the lamp lights up as a signal, and this
dial here which is really a calibrated galvanometer,
shows how far away the object
is."
He pointed to one of the three dials
which I had noticed was calibrated in
yards.
M iiiiiiiMi Ill iiiiiiiiiiiiiiiiiiiimiiDiiiiiiin I"
11 IN THE JUNE "E. E." |
II An interviezi! with Thomas Alva I
11 Edison, including some new photo- \
II graphs of the famous inventor. \
II Electricity and Life by Dr. Fred- I
II erick Finch Strong. Part III of
II this interesting and valuable series.
if Woman's place in the Wireless
11 game — A page of female radio
11 operators who have made good.
|| The How and Why of Radio Ap-
II paratus. Part II'. Spark Gaps.
|| The Calculation and Mcasurc-
11 ment of Inductance. Part III of
II
II
II
11
this valuable series by II. Win field
Sec or and Samuel Cohen.
Another gripping electrical talc—
"In the Way" by C. M. Adams.
Don't miss it!
Feature Article— "Electricity's Aid
to the Fair Sex"— of interest to
everyone.
Building a High Frequency Alternator
for use in Radio by S. Cohen.
E.vperiinentcil Physics. Fifth
Paper by John J. Furia, A.B., M.A.
An Electric Player for Tubaphones.
A home-made electric searchlight
for the amateur by Frank M. Jackson.
IHIIigillllllllllllllMlllllllllllllllllllllKI
"What are the other dials for?" I asked.
"They are to give the angle of the coil,
both in the horizontal and vertical planes.
You see both are calibrated that way.
These wheels here turn the coils about
and raise and lower them, and this third
wheel operates the mechanism which raises
the coils clear of the conning tower."
I saw then the whole perfect simplicity
and accuracy of the device. I marveled at
it.
"Then you can run under water without
even a periscope exposed and locate
the exact position of the enemy," I said.
"Exactly, you understand it perfectly,'
he replied.
-—^-—^^^^- "^^^^^^^ "Then you can aim your
torpedo with accuracy," I
went on.
"Torpedo I"
with an
he snorted
exasperated
frown. "Didn't I tell you
that we didn't have one of
those antiquated devices
aboard this craft?"
"But," I went on, "you
must have something to
sink the enemy after locating
him."
"VVe have," he said, his
_^__^__
face brightening
fully.
"Well, what is
asked, puzzled.
hopeit?"
I
"Look here, Dick Hartman," he said in
mock seriousness, "do you mean to tell
me that after seeing this feeler work, you
can't understand how we could sink a ship?
You, a graduate of the best technical school
in the country and a practical electrical
engineer, can't understand that?"
I confest that I did not.
"Then you're either asleep or haven't the
least trace of imagination," he said, turn-
ing away in disgust.
"Well,
asked.
how do you do it anyhow ?" I
"I'm not going to tell you. I'll let you
find out for yourself first," he retorted
with
and
a show
walked
of his old boyish perversity,
into his room and left me
wondering in front of the feeler dial.
But I could not follow his line of reasoning
to its end. I thought of it as I tried
to sleep that night, while the motors
thrust us forward and our long hull svva>ed
gently as we topt the crests and fell into
the hollows. I puzzled over it as I sat
at my instruments and waited for my call,
or anj'thing else my receivers could pick
from the ethereal vibrations about us. But
I could make nothing of it. I could see
no way, no means by which wc could sink
an enemy ship with this curious little feeler
device which with all, was e.xactingly accurate.
.All that night we ran and all the next
day. I did not ask Billy any more about
our boat. Pride perhaps kept me from
doing this, and impatience at my own lack
of perspicuity and imagination. .\nd then
too I was busy with my own work and
other things that came up, which had to
be done in the crowded under-sea craft.
I prowled about it in what spare time I
had, tni'ing to see what I could between
tricks at my table. I found that it was
quite the usual large-sized submarine, of
which the navy had an even hundred not
counting ours. It was driven by electric
motors supplied by turbine driven generators
forward. It was provided with the
usual gas absorption system which made
it possible to run under water with our
steam power, without discharging any exhaust
gases; this, the first important invention
of the Xaval Consulting Board. But
I found the forward torpedo room_ locked
and none on board had gone into it since
they had been on board, none save the
chief engineer, Dickenson, a man from
Parker's own electrical company, which
had built this curious boat and sent it out
(Continued on page 66)