The Dolores star., 1923-08-24


TO penetrate the darkness for some sight which
will give the vessels location
suddenly, from distance the Shriil.
long -drawn-out call of a siren. Eagerly the cap
tain listens rs the sound is repeated at regular
Intervals Then his face brightcns. II is a voice
which he has often heard before and there is no
1!stakng IL Only the fog signal of the Sandy
Hook East beacon gives that eight-second blast
every minute. So now the captain knows exactly
where he is, orders fly to the engine room. and
The ship is headed toward safety.
There than six hundred such fog sig.
mails In use in the coastal waters Of the United
Estates. Not all are of the same type the
same system in emitting their warnings There
are steam whistles and sirens: air whistles
Sirens, diaphones and horns. There are bell buoys
operated by cockwork. electrical apparatus en-.
Eine and by hand And there submarine bells
operated by compressed air and by the sea Itself
These signals. however form only a small part
of the elaborate system of aids to navigation which
Is under the direction of the United States light
house service. II is rather remarkable that this
service although one of the Oldest and most i'm
Portant of all government departments is very
little known TO the general public. This is prob
ably due TO the fact that the service Is performed
largely at sea, where comparatively few people
come into contact with It,
There is an office in Washington. known as the
bureau of lighthouses. which is the executive cen.
ter of the service The service outside Of Wash
1ngton Is divided into 10 lighthouse districts each
of which is under the charge of lighthouse in
spector. A lighthouse depot is conveniently
located in each district for carrying on The local
work in the matter of storing and distributing SUD-
plies and apparatus.
! The aids to navigation In the United States
Today number more than 1900. of which onethrd
are lighted aids, and the others unlghted-such as
FOG signals submarine signals buoys and beacons
OF the lighted aids. about 800 are major lights
employing range lenses refectOrs and lens lanterns
and requiring the services Of one more 'seepers
These are the lighthouses. Light vessels are used
as rule to mark offshore dangers the ap-
proaches to harbOrs or channels where lighthouses
would not be feasible or economical.
The type adopted In each case for lighthouse
construction depends largely on the importance
of the light and the foundation conditions. com
mon form, frequently used for hnrbor lake
lights, Is combined tower and dwelling of timber
brick construction. Many lighthouses at the
entrance 70 harbors are built on the end of breax-
waters pierhcads. utilizing. as a rule such
structures the foundation. In the case of light
houses or submerged sites the engineering features
are important and often present great difficulties
both in design and construction
The earliest type OF lighting apparatus consisted
Of open coal wood fire with other infan-
mable materials. such rs pitch burned In a bra
zier, on top Of the tower. When Boston light at
the entrance to Boston harhor, and the first light.
house built this continent, was established in
171G, the common oil burner of the period was
used nclOsed in a lantern consisting Of Il cylinder
of heavy wooden frames holding small, thick panes
of glass. The lllumlnaut fish or whale OIL
burned in spider lamps with wick and suspended
by Iron chains from the top of the lantern
improvements were gradually made until there
evolved the present modern lighthouse with
tts complex system Of revolving lenses. at the
focus Of which is placed the source Of light The
largest lens In use In the lighthouse service at
present Is that at Makapuu Point. Oahu. Hawaii
the landfail light for vessels bound from the States
to the Hawaiian islands, The inside diameter of
this lens is almost nine feet and It Is nclosed In
specially designed lantern Of sixteen feet inside
diameter. This light is visible at from dis
tance OF almost thirty miles
The brightest light in the service and generally
considered the brightest in the world, Is at Nave
ink, N j., at the entrance to New York bay The
candle power of this light is estimated at 25ODO.
900, and Its glare has been at distance of 10
miles at sea. This great intensity is produced by
q powerful electric inclosed in modern lens of
high maEnifcation In most other important lights
the incandescent oil-vapor lamp. which burns VA.
porized kerosene under incandescent mantle
and gives very powerful light. Is used