Evening star., 1935-01-20

- Jervis, N Y, highways are blossoming
out at night with weird looking yellow
lights.
American motorists last Summer, like
their counterparts across the Atlantic Ocean.
ran into the new yellow glow Of the new high
way lamps. The experience seemed strange
at first.
Green leaves on trees looked white, as did
the grass. Nocturnal rural Landscapes ap-
peared snow-covered. Yet If the motorists but
knew 1t they could have sped through the
yellow lighted country side at 60 and more
miles an hour in safety even with their head
lights out
Greater safety for night driving Is the func-
tion Of the new yellow lighting. The yellow
color Is produced by glowing gas Of the metal
sodium, best known perhaps q constituent
Of common table salt
Sodium vapor lamps really do help highway
safety at night. Under the yellow glow ap-
preaching cars are more clearly visible. To
drive on q road illuminated with the rays from
sodium vapor Is 70 enter new world Of light
ing where the eyesight Is sharpened to prevt-
ously unknown powers.
Yet the new lighting IS not necessarily in
tensely bright, like the Kleg lights of the
movies While sodium vapor lighting makes
objects stand out more clearly. there Is no
glare about 1t.
CODIUM vapor lamps came to the United
States by way of Holland. Following
pioneer installations in Europe three years ago
the great American electric companies like
Westinghouse and General Electric have
jumped into the new lighting field in this
country.
Just because it is q pioneer field is the reason
present installations were started ON the Ball
town road minor highway near the Sche-
nectady works Of the General Electric Co. In
June, 1898. Gradually the systems are being
installed about the country in more populous
localities. Next Summer it will be an excep-
tonal tourist who does not drive on some
highway having at least a short section lighted
by sodium vapOr lamps.
Sodium vapor lighting appears to be one in
vent1on which pleaSeS everybody. State motor
vehicle commissioners like the yellow-colored
lamps for the promise they hold of decreasing
highway accidents. Individual car owners may
very we'll be pleased for the same reason
Power companies, whether privately or pub
licly owned favor them because of their
economy.
To obtain the same quantity Of light from
sodlum Vapor lamp as from a tungsten fila
ment 1ncandescent lamp means much less elec-
tricity passing through a sodium lamp Ex-
pressing this luminous efficiency as would an
illuminating engineer, sodium vapor lamps
yield SO lumenS per watt of electrical power
where the ordinary incandescent street lamp
gives only 10 lumens per watt.
But do sodium vapor lamps really enable
one to see more distinctly? The answer is
yes, and here's the reason.
How accurately the human 'tsees' an object.
from swift-moving automobile to fine type in
newspaper. depends in part on what kind Of
light Is used to illuminate 1t. And there are
many kinds of light.
Light from the sum- as one familiar example.
Is spoken OF as white light as If white were
true color Actually white is the word by
which man deScribes-in most cases without
knowing 1.-THE sum total Of all the colors from
violet. through blue. green and yellow to the
deepest red
Mans nighttime sun-the incandescent elec-
u1c hght-gives of something like white light,