Evening star., 1924-10-26

astronomer. it comes closer home.
The studies in heat waves reflected
and absorbed by various materials led
TO the announcement that a tent will
keep out 80 per cent Of the suns
heat If the cloth is painted outside
with white paint and inside with
aluminium paint, and that painting
the roof Of an ice wagon with alumi-
mum paint will cut off half the heat
which usually gets through to melt
the ice. The building industry was
astonished to learn that for the same
reason a radiator painted with alu-
minnm rs only one-third as efficient
as one painted with ordinary paint.
Shark Hides for Leather.
When leather shortage impended
experts sought new sources of leather
and turned the shark to good account.
Sharkskin, tanned and tested. was
found suited to the manifold uses of
| leather. The same experts studied
the wear of shoes, the quality of
| leather and turned the results over
to the American shoemakers. A
walking machine was invented to i'm
| itate and speed up the wearing out of
sole leather by walking The ma
chine gives the same wear in a few
hours as months of service would
give.
Extremes meet and diverse prob
lens depend for solution on simple
facts scientifically applied. From
teeth filling to non-chipping enameled
kitchenware is not so far, for the
same experts and, the same problem
are involved in both. If metal and
glaze expand or contract differently
with heat and cold, the glaze peels
off; il teeth and amalgan expand and
contract differently, the filing works
loose At dinner this happens when
we close the meal with hot coffee and
| ice cream.
Mounted on an automobile ready
for the road is a wonderful piece of
| mechanism which makes an auto
| matte and graphic record of the per-
formance of an automobile in full
road service. 1t records measured
| data for 16 items of automobile per-
formance which the designer needs
to develop a perfect power system.
Thus new era opens for designer
and builder by. enabling them to use
the measured performance charts of
every sort of road condition, car op-
Grafton, wind and grade. The perfect
car Of the future is being created by
| such tests.
Steering Ships With Radio.
The magic of radio Is used in most
practical ways. The bureau sends a
| narrow shaft of radio waves like a
| searchlight down Chesapeake Bay
from Washington to Norfolk. Ships
| crossing this narrow beam can tell
their location and follow the path of
| the radio beam in a fog or on a dark
night. 1t needs no dream to visualize
future navigation on the seven seas
without sextant or magnetic COM
pass, but with a network of slender
directed beams of radio making the
| trackleSs water as easy to navigate
| as the Sereets of city.
! Experts cannot travel with a pro-
jected shot through the air and study
its behavior and the effect of the air
upon it. But the Bureau of Stand
ards can do practically the equiva-
lent Placed in an experimental wind
tunnel, the projectile is exposed to
wind speeds 10 times those of the
! swiftest hurricane. With wind blow
| ing thousand miles an hour past the
projectile, almost identical conditions
of gun-fired shot are duplicated
Even the strong compression wave in
| front of the projectile may be studied
| The Bureau of Standards is laying
a basis for its great work in the fu-
ture in ways unknown to the public
| In an underground laboratory is an
improved ultramicrometer, thou
sand times more sensitive than the
precision gagemakers' apparatus
This instrument measures length
| changes as small as the billionth of
an inch, and is so far ahead of practi-
cal uses today that it may wait for
years before industry needs or can
use such inconceivable delicacy and
perfection of length measurement
When men can measure the heat OF
| the stars, they are making truth
| stranger than fiction. When they
harness the hurricane, they are MAX
| ing magic real. When they can steer
| the mariner with beams of radio,
they are outdoing the Arabian Nights
This is why the National Bureau OF
] Standards is q house Of wonders.
wi<h< Il