Evening star., 1915-01-31

weight brought down from English
ancestors, was simply reduced to the
terms of the kilogram. 1t was calcu
lated that a kilogram contains Just an
infinitesmally small fraction over two
pounds. SO the pound weight is just an
intinitesimally small fraction over half
of a kilogran.
This prototype kiloEram which is the
real standard of weight in this country
is kept under two glass globes in
case in steel vault in the basement of
the bureau. carefully locked from all
dust. heat or moisture. 1t was brought
over to the United States in 1890, and
opened by President Harrison at the
White House.
This same international conference
adopted the meter the measure in
length. But the yard having been al
ready used in accordance with the old
English ways, was not amenable to
this length in exact terms. The Ameri-
can yard today is SO inches-a meter Is
1881 inches. Yet the standard yard is
calculated on this relation to the meter
to make 1t absolutely correct according
to international measurements. The
Partisan international meter, like the
international kilogram, is kept in the
French vaults. but our meter, which
was received from this international
conference, is an exact copy. 1t reposes
in the vault of the bureau by the side
of the kiiogram. and is long bar OF
platinum iridium. By it's side is
y ~ .
inches shorter.
Another important work is that Of
establishing a standard time measure.
For this purpose there is the precision
standard clock. q mechanism made in
Germany of the finest workmanship
possible. 1t tells the minutes, seconds
and hours, and reposes in a double glass
stand. which is partially exhausted of
air. The air which enters the case Is
made absolutely devoid of moisture by
passing through chemicals. This ma
chine winds itself automatically every
thirty-two seconds. The absolute time
is obtained at the bureau astronomi-
cally. and also by comparison with the
clock at the Naval Observatory. Makers
of watches, clocks and chronometers all
over the country have their timepieces
tested by this clock, and even private
parties are allowed to leave their
watches for this purpose.
In the matter of making standard
for colors the tinting of ray of light
is used in the test. Colors are easily
faded, and there are myriads of varia-
tions in one shade. But by obtaining
the tint of the different rays of decom-
posed light an absolute standard is
secured This is of inestima BILE value
to manufacturers OF colored goods.
Scales for testing the correctness Of
other peoples weights are used in any
the purpose cf which is to judge OF
fifty pound weights. 1t is kept in a
glass case and the balancing is done by
a wheel on the outs de. that no
human hand enters. Even the addition
of tiny bit Of metal as large as the
head OF pin is done by manipulation
from without. Mach mes so delicate that
they can weigh the down on butterfy's
wing are kept in a vault in the base
ment secure from heat. dust or damp
ness. TIC prevent even the warmth from
the body entering into the problem the
scales are observed by instruments and
through window of an adjoining cham
ber
The weights used are so small that a
breath would scatter them-some are not
so large or heavy as fly's leg. They
are used by picking them up with 4
pair o. very delicate tweezers. II a bit
OF blank paper be weighed and then
written on and weighed again. the scales
will show the weight OF the lead de-
posted on the paper by the writing In
other words. any one can thus know the
weight of his name.
The candlepower of electric lights is
another exceedingly complicated mat
ter which has been perfected. After
much delicate testing q dozen lights