Evening public ledger. [volume] (Philadelphia [Pa.]) 1914-1942, 1920-08-17
JUNkiNC THE SExTANT
Science Within Distance Of Run
ming Ships Like the Trains OF
a Great Railroad system go.

~ making navigation of the seas easier
and safer and Is taking from the snip
captain much Of the worry and uncer-
tainty Of conducting his vessel from
one port to another in spite OF wind
and weather.
The day is even visioned now when
the merchant fleets Of the world will be
run like the trains Of great railroad
system, with all the controls in fixed
centers with the schedules made out
in advance and with something almost
analogous to the steel rails to keep them
steadily and [ Tie upon the paths
mapped out for them.
When that day comes. the navigation
will be done from shore far more un-
erringly than it can be done now NJ
sea, and the captain will be merely
conductor, to punch the tickets of the
passengers and see that all Is kept in
order aboard. There will be no Sex
tant, no pelorus, no aziinuth mirror,
no daily calculations of chronometer
errors, and the compass will make Its
own corrections and keep the ships
head on the course required
THE latest step is the laying OF
L sixteen mile cable down the harbor
Of New York and out she Ambrose
channel. BY means of mn alternating
current of electricity in this cable and
sensitive audiphoncs. one on each side
Of the ship. q vessel approaching in q
fog or in a bad storm can proceed
steadily on its way up the narrow chan-
mel and entrance and anchor in the
protection of the Narrows under condi-
tions that would now make such feat
out Of the question.
The sounds in the audiphoncS will
guide the ship to the outer end OF the
cable: that reached. she will proceed
and the audiphones will tell Immediately
II she swerves in the slightest from the
water directly over the cable. and she
can be quickly brought back on her
course. 1t will be much like a trolley
car following its. wire, only here the
connection will be by means OF the
impulses propagated through the water
instead Of through the pole on the car.
A LREADY the wizards of electricity
"A have furnished to mariners on our
coasts a method of locating their posi-.
tions at sea with greater speed and
accuracy than are possible with scXtant
and mans falliblc methods OF calcula-
tions.
Just before the war started wireless
compass stations, or. as they are tech
nically called goniometer stations,
passed the experimental stage. and
when the United States entered the
conflict these goniomctcrs, in portable
form. were used by the government to
locate all secret wireless stations whose
existence was suspected.
The entire length of the Atlantic
coast was also equipped with them:
and this important branch Of naval
work was placed for development in
the hands of Philadclphian. LiCuten-
ant Appleby, who had been known here
for many years as a maker Of wireless
instruments for amateurs.
Today these compass stations are
busy twenty four hours in every twenty
four. receiving requests from ships at
sea for position reports, and the speed
and accuracy of these reports are caus-
ing captains to depend upon them more
and more.
THE method by which this most i'm
l. portant operation is done is in
tcnsely interesting and entirely un-
known to the general public.
Let us suppose a ship is bound up
the coast for New York and, somewhere
below Hatteras, has struck bad weather.
which has made her dependent upon the
uncertain methods of dead reckoning
for her position. Her captain, knowing
that he may be many miles out OF ms
course, asks the wireless operator
whether he can get her position from
Virginia Beach or Cape May.
The wireless operator, listening IN,
finds, perhaps, that he can hear Cape
May stronger than any other station,
so he calls up that wireless office and.
getting an answer. sends the sigma
"QFTf" which, in radio parlancc:
means, "What is nv position, plcaseE
The Cape May station will give him
the signal *" which means Go
ahead" and the ship operator will
send his call letters over and over for
thirty seconds. and then make dashes
of five seconds duration for one minute.
on shore, two other
AS1 stations, connected by private wire
to Cape May. have been told to listen
for him and. while he is sending his
"tuning" call letters and dashes. these
two operators. at Cape Henlopen and
bethany Beach, Del. have been ma
nipulating their goniometers until each
one has determined the exact direction
by true compass from which his signals
are coming.
These two directions are sent over
the wire to Cape May, and an expert
in that station. which Is known as the
Compass control station has laid
down the two lines on chart and
located the point at sea where they
iutersect. This must. of course, be the
ships exact position. and Cape May
Immediately sends it to the operator
upon the vessel.
ALL along the Atlantic coast these
"A control stations, with two or three
goniometer stations, have been located
at every important harbor entrance
and give positions for ships fifty miles
distant.
At other points along the coast are
independent stations that operate with
vessels up to $50 miles and give bear
ings only, but when a captain gets an
accurate bearing of his ship from two
different points he himself lays the lines
down on the chart in his chart room
and 20 locates his position.
The system is sufficiently devel-
oped at the present time to make it pos E
sible to take ship from Boston down
the coast and into the port of Havana
without a Rcxtant aboard. The new
submarine alternating current cable in
New York makes pilot ma longer
necessary.
rs THE time coming when even the
l. power necessary to run the ship will
be transmitted from shore by means of