The Holly chieftain., 1923-08-16

eager, 6IfalnlnH eyes Whlch seek
TO penetrnte the darkness for some sight which
will give the vessels location
Suddenly from a distance comes the shrin,
longdrawn-out call Of n siren. Eagerly the cap
tain listens as the sound Is repeated at regular
intervals Then his face brightens. It is voice
which he has often heard before and there is no
mistaking 1t. 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 ia orders fly to the engine room and
the ship is headed toward safety,
There are more than six hundred such fog sig
mails in use in the coastal waters Of the United
States. Not all are Of the came type or use 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 clockwork. electrical apparatus en-
Gine, and by hand. And there are 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
u under the direction of the United States light
house service. It Is rather remarkable that this
service, although one Of the oldest and most i'm
portant OF all government departments Il 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 GEN.
ter Of the service. The service outside of wash
fngton Is divided into 10 lighthouse districts each
OF which IL under the charge Of lighthouse In.
spectof. A lighthouse depot IL conveniently
located In each district for carrying on the local
work in the matter Of storing and distributing SUP
plies and apparatus
The aids to navigation In the United States
today number more than 1900, of which one-thrd
are lighted aids and the others unlighted-such as
fog signals, submarine signals buoys and beacons
OF the lighted aids, about 800 are major lights
employing range lenses reectors and lens lanterns
and requiring the services of one or more keepers
These are the lighthouses. Light vessels are used
as rule to mark offshore dangers or the ap-
proaches to harbors or channels where lighthouses
would not be feasible 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 harbor or lake
lights, Is combined tower and dwelling of timber
or brick construction. Many lighthouses at the
entrance to harbors are built on the end Of break-
waters or pierheads, utilizing, as q rule, such
structures the foundation. In the OF light
houses on 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 an open coal or wood fire. with sother infam-
mable materials, such as pitch, burned in bra
zier, on top Of the tower. When Boston light at
the entrance to Boston harbor. and the first light.
house built on this continent, was established In
used, incosed In lantern consisting OF cylinder
of heavy wooden frames. holding small, thick panes
of glass The illuminant was 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
was evolved the present modern lighthouse with
its 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 nndfal light for vessels bound from the States
to the Hawaiian Islands. The inside diameter of
this lens is almost nine feet. and 1t Is inclosed In
specially designed lantern Of sixteen feet inside
diameter This light Is visible at sea from a dis
tance Of almost thirty miles. -
The brightest light in the service, and generally
considered the brightest in the world. is at Nave
sink, N. j., at the entrance to New York bay The
candle power of this light Is estimated at 25OOO.
O00 and its glare has been at distance of 70
miles at sea. This great intensity is produced by
a powerful electric inclOsed in a modern lens Of
high mngnifcation In most other important lights
the incandescent oIl-vapor lamp which burns va.
porized kerosene under an incandescent mantle
and gives very powerful light Is used.