Washington standard. [volume] (Olympia, Wash. Territory) 1860-1921, 1912-11-29

B. the Aid Of the Wonderful Sun Valve
Sets at Night and Extinsuishes Them
as It r ises In the Morning.
The sun is the most trustworthy OF
/ lighthouse keepers. The sun or the
heat from ii lights many hundreds OF
bcacouS along our coasts and water
ways evening after evening and eX
tinguiSheS them punctually every morn
Ing They are guides on land and SEA
that are never touched by human hands
from one months end to another. The
way in which the United States gov
eminent, through its lighthouse board
has utilized the services of the sun anC
! made that great lamp of heaven q
/ faithful and unerring servant is most
| interesting
The discovery Of acetylene gas was
! the first step toward retiring the lonely
keepers of the little lights in farofi
| places. Modern magic was not slow
| in recognizing the fact that by the ap
plicntion of certain well known scien
tifc principles the lighting of the grea,
chains of beacons that girdle the coasts
of the two seas and the gulf and cover
the great lakes and every navigablt
stream in our huge country could bt
much simplified.
The United States did not become In
! terested in the acetylene light and It's
! automatically generating gas buoy unit
about the year 1906 and did not adopt
1t until 1908. Then the engineers OF
wonderful improvements, among then
the utilization of the sun.
The self lighting and self extinguish
ing acetylene beacon is very simple
thing. but it depends almost entirely
on the "sun valve" which is one of the
most wonderful but least complex OF
the achievements of modern science.
In the first place. the source Of light
| for these lone beacons Is dissolved
acety lene, which is stored under pres
sure III steel cylinders. One of these
| cylinders can be charged with enough
gas to last small beacon three years
Usually, however, in the case Of float
ing buoys. six months supply Is al
! that is necessary, as such buOyS are
overhauled and painted twice year
Knowing the size of the flame aud its
hourly consumption Of gas. it is very
easy to compute how long cylinderfu,
will last and how often it will need tt
| be visited. That Is all the care the
light will need. The sun valve does
the rest.
The scientific principle upon which
the sun valve depends is that light
waves become transformed in different
degrees. according to the nature of the
intercepting body. Sunlight upon dark
surfaces is converted into heat, and
heat produces expansion. This expan.
sion is especially perceptible In certain
metals.
In carefully sealed and substantial.
~ mounted glass jar nearly a foot
high and about one-fourth that in di.
ameter thick black rod is placed per-
pendicularly through the center. 1t is
supported by three slenderer rods OF
highly polished copper. The big black
rod is of copper also and is coated with
lampblack to make 1t absorb light tC
the greatest possible degree. The sup.
porting rods reflect light without alb.
sorbing it and do not expand or con
tract to the same extent as the largest
rod.
The thick black piece Of copper in
the center Of the jar Is extremely sen.
sitive to light and heat. AS the sun
appears and the atmosphere grows
warmer In the morning this rod length
ems. 1t pushes down into the metal
chamber in which the glass jar rests
and touches the end of lever. II
presses down on this lever. which is
controlled by spring and cuts or the
flow Of the gas to the lamp.
When the sun disappears from view
in the evening and the temperature OF
the air falls the process Is reversed
The rod contracts and releases its pres
sure on the lever, allowing the gas to
flow upward to the lamp. The gas Is
ignited by little pilot fame that ID
never extinguished. Thus the beacon
is lighted at the proper time and is put
out when it is no longer needed, al
though along desolate coasts 1t may
never gladden. the human eye fol
months at a time.
The engineers Of the lighthouse board
say that the precision Of this device is
almost incredible. 1t can be used with
equal certainty in equatorial heat and
in polar cold, for 1t responds with the
utmos. accuracy to small variations In
temperature. 1t Is used on lonely Is
lands in the Pacific. There are nearly
hundred Of these sun valve beacons
In Alaska. In summer they are aids
to navigation, and in winter they guide
the travellers on dog sledges over the
frozen wastes.-Harpers Weekly.
Deadly.
Al,..A boo 10 vuvN