San Antonio light. [volume] (San Antonio, Tex.) 1911-1993, 1923-04-29

out as much as is possible without
having dark center.
Whatever may be the required posi-
tio1, move the lamp back and forth
by means Of the focusing device until
this position is attained.
Some headlights are so constructed
that when the lens and rim are put in
place the reflector is pushed back. In
such cases the bulb should be put a
little back from correct focus.
Probably the commonest defect in
automobile headlights is that the lens
is not correctly put in. All the best
types have a definite vertical axis,
which is usually indicated By marking
top" on one end of it. This top
should be exactly up. Many good lenses
are giving poor service because this
is not done.
The effect of such maladjustment
is obvious. The lens is designed TO
spread the light out into beam that
is wide horizontally, and low vertical
~. II the axis of the lens is not
vertical the beam may spread upward
at an angle on one side. and will
thus put a powerful glaring light in
the eyes of anyone facing the car
on that side. 1t is also important TO
have both lens and reflector clean.
Will Test Headlights.
A free demonstration Of testing
methods will be given at the Bureau
of Standards. Connecticut avenue. and
Van Ness street. Washington, from
May l 10 May Z, the demonstration
lasting from s to 10 p. m. each day.
At this demonstration anyone who
At this demonstrate, n anyone who
Minor adjustments easily made will be
made by the tester. If adjustments
are required which are more difficult
TO make the driver will be given a
card telling him what is wrong with
his lights. and this will enable him TO
fix them himself or to have his garage
man fix them.
The bureau of standards has been
making many tests on headlights re-
Gently with a view to obtaining in
formation to serve as a guide in i'm
proving hcadlighting cond ions. 1t is
now possible to specify the distribu-
ton of light that should be given. and
to tell by simple methods whether a
given device conforms TO the require
ments.
IL is recommended that the state
officials in charge of moto- traffic
regulation prepare lists of approved
devices which meet the requirements.
and that these devices be permitted
within the limits of the States. Such
lists should he uniform throughout the
country. in order that man may
not have to change his lights in going
from one state to another.
On account Of he liability Of getting
ont of adjustment. frequent tests
should also be made. 1t is very easy
to do this. and garages should add
testing screens 10 their equipment. The
police should also be equipped with
testing screens with which lights could
be tested that we're suspected of being
not in accordance with the regula-
tons.
The testing screen used at the bu.
reau of standards is plain piece Of
canvas on which the necessary lines
nre painted. ANY other white cloth
will do just as well. The screen may
be fastened to a wire fence. the wall
of building. or light portable
frame especially made for that pur-
pose.
1t is desirable that reference screens
should also he provided. being plarcd
at the police station. to which dis
puted eases could he referred for
more exact test. The bureau can fur
nish information about the construc.
ton and use Of such n screen.