Evening star. [volume] (Washington, D.C.) 1854-1972, 1911-10-18

a the national bureau of stand
~ ards one may have ocular dem
- onstration that TRUTHS stranger
= than fiction. In one room OF
this remarkable institution is a
giant testing machine powe. iul enough 10
pull asunder great steel shaft In another
room the visitor may behold by optical
means the bending of tool steel shaftinS
three and a half inches in diameter be-
meath the weight of a visiting caro-.
Across the hall is weighing machine
with balance so sensitive as to register
the decrease in weight of a piece of metal
when moved two inches farther from ne
earth
In another room are to be found length
| measures so delicate that their scale can
be read only by the aid of a microscope
magnifying 80 diameters, and which,
| when being used, are packed in ice so
that the variations of heat may not at
feet their accuracy. In still another
room the visitor may study the ultra
violet rays Of light, such as the unaided
human eye has never seen. At another
place he may see men testing thermome
tiers which register a temperature below
the freezing point of pure hydrogen, and
others which will accurately measure
heat up to approximately 7.OoO degrees,
q heat so intense that no earthly sub
stance can survive it.
The layman can hardly appreciate how
close home to him comes the work of
the bureau of Standards His groceries
are bought by standard measures; the
imported sugar in his coffee at break
fast has been tested by the bureau for
the customs service The electric light
by which he reads at night conforms to
the standards of this bureau The clinical
Thermometer ha
tains his temperature when he is sick.
and the apOthecary scales by which his
medicines have been measured. owe their
accuracy to the work of this bureau.
The bureau OF standards is the home
of precision, but not Of undue precision
for the bureau aims to assign to each
case the order of accuracy 1t deserves
a clinical thermometer, correct to a tenth
of degree, is tested in few minutes.
If. however. a standard of length, yard
or meter, is for some great manufa ctur-
ing plant where measuring instruments
are made weeks are spent in testing
single standard, while fundamental ma
tiOnal standards take years to establish.
The modern metric standards of length
and mass took fifteen years to prepare.
verify and distribute to the governments
Of the world.
The unique facilities for scientific work
at the bureau attract visitors from every
land. A liquid-ar plant affords freeZins
temperatures almost to absolute zero:
electric furnaces give heat enough to melt
rock: machines are at hand to freeze the
moisture from the air and provide a new
dry climate wherever required; through
large tunnels run a multitude of pipes
and wires, carrying not merely hot, cold
and iced water, but steam, vacuum and
compressed air to the various labora
tories. Every room needing special time
service can be wired to beat second in
tervals from that marvel of precision
the Riefer clock which runs correct to
within half a second month. There are
ice-making machines, gas making ma
chimes, ventilating systems and remark
strengths of electric current may be
sent to any room as easily as a telephone
connection is made. In the glass-work-
ing shop wonderful tubes are made for
vacuum lamps. elaborate apparatus of
glass for regulating temperature of tanks
of Oil to the hundredth part of l degree,
and many other intricate works Of skill.
Then there is the glassworker who grinds
true lenses and fiat surfaces to marvellous
accuracy for optical research
Respect for the infnitesimal is cardi
nal virtue in the bureaus work; no fac
tor is too small to be ignored, no labor
too exacting, no expense too great when
national standards are involved. Scien
tific discovery now rests upon that re-
fined scrutiny of things which marks pre-
cision measurement With more exact
measurement of the moons distance,
Newton might have announced his dis
coveries many years earlier. Accurate
weighings of the nitrogen of the air
showed a slight excess weight due, as
Ramsay found. to FIVE new gases which
were till then unknown. So, with the pre-