The Emmett index. [volume] (Emmett, Idaho) 1893-1925, 1915-04-15

: thus elevated five centimeters (abou
3 two inches). 1t was found that tn
: weight was O.016 miiiigrams less tina
/ when they were side by side. Til
/. precision of this instrument can b
: appreciated by this experiment, for
shows that it can weigh down t.
: LOO, 100000 OF the whole.
Some of these balances are so deli
cate that the heat of the operator
body near them would cause disturb
ance, and the adjustment is effected
by rods and other ingenious mcchan
isms, which change the weights from
/ pan to pan or add the finer V-shapec
weights to the cross beam to effect {
perfect balance. The operator stands
at distance CT 10 feet and reads the
result through telescope.
One Of the balances used in the vol
] tameter work is so delicately adjust
ed and sensitive to changes of tenn
perature that the operator cannot
even remain in the same room with it.
1t is kept in room guarded by dou-
BILE doors, in which constant tenn
perature is preserved. The rods by
which it is controlled reach through
double glass panels into a second
room, which is also at an even tenn
perature.
In the division charged with the
standards of heat, researches are be-
ing conducted which it is hoped will
lead to international agreement as to
the standard scale of temperature,
for, strange as it may appear, only
two points are at present standard
lied, namely, the freezing and boiling
points of water. Above and below
these nothing is fixed.
Here the clinical thermometers used
by the medical profession are tested
and their accuracy to the tenth of a
degree certified, upward of 10000 be-
ing handled in the course of year.
Here are tested the delicate Beckman
thermometers, which are used by
chemists and engineers in the trials |
on which the award of large fuel con-
tracts are based. The high tempera-
ture thermometers, reading up to 1000
degrees Fahrenheit, and the low tenn
perature pentane thermometers, used
for temperature as low as 300 degrees
below zero Fahrenheit, also receive
their share of attention.
In another room is to be found ap-
paratus by which such intense cold
can be produced that even the air we
breathe becomes liquefed, and can be
handled as so much water. Put bar
of steel into it and it will burn as if it
were finder, in spite of the fact that
the steel and the air have been in
tensely cold.
Hard by is another room where they
go to the opposite extreme, to the
point where we begin to realize the
meaning of the expression "fervent
neat" Here the hardest metals that
exist melt as pile of snow before an
April sun. Yet they have to devise
heat measuring instruments as sturdy
as the bolometer is delicate, so that
hey can endure it and register its
In the division of optics many tests
ire made for the government and the
seneral public of telescope and pho
ographic lenses, prisms, samples of
lass, and optical instruments and ac-
essories. Work has been planned
which will lead to the Standardization .
f the eolors of textiles, papers, to-
accos, butter, dyes, liquors and many
Their commodities.
The fundamental basis of the work
f this section is the light wave. If
II the standards of length in the
hole world were by some accident
the meter could be exactly
eproduced from the red line in the
oectrum of cadmium, as it is invari-
BILE, exactly 1,553,16 of these wave
myths forming the length of meter
Light waves form the unite of meas
rement in one of the most precise
known to science This is
lie interferometer, which can accur-
ely determine differences in length
small as two-millionth of an inch, u
measurements so minute as to be
,yond the range of the microscope.
To show the delicacy of this method,
e bureau has evolved remarkablelI
ientifie device with which the visitor
n see the bending of steel bar
rec feet long and three and one-halt
ches in dimeter beneath the pressure
one finger,
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