Amador ledger., 1906-05-18


Saliva. Liquid Airs Real Use.-
The Suns Temperature.
Glass from pure quartz can be heat
ed to 1000 degrees Z. without soften
ing, is not cracked by sudden changes
of temperature, and is otherwise OF
great value for scientific and other
purposes. 1t is prepared with great
difficulty, however, the quartz appara-
tus now in use having been built up
by piecing single crystals together by
means of the oxyhydrogen blowpipe.
When quantity of crystals is fused
the mass is made Opaque by air
bubbles, which cannot be removed,
and varied experiments have made it
evident that clear glass is not likely
to be obtained by direct fusion at
atmospheric pressure. An effort to
solve the problem by other means has
been made at the Carnegie Institution
with fair success. The quartz, in
graphite crucible, is first heated to
1000 degrees or more, to produce
quartz vapor enough to drive out the
air from between the grains, then
pressure of 500 pounds or more is
quickly applied and the temperature
is lowered to perhaps 1900 degrees for
talf an hour, when heat and pressure
are slowly withdrawn.
Raising the temperature of bare
platinum wire from 800 degrees e. to
$40 degrees more than doubles its
brightness, while doubling the tenn
perature of white-hot body is esti-
mated to Increase the luminous in
tensity 1000 times. With this in
mind, Adolf Herr, a German, has
passed an electric current through an
Auer glover of metal OXIDES heated
by gas-fs;me, and has thus consider
ably raised the temperature. The
result is an extraordinary increase in
luminous efficiency.
BY means of ergograph measure
ments, M. Charles Ferre has found
that one-tenth more work can be
done standing than sitting, but that
the greater intensity of effort during
a long period in the standing position
is followed at the end by more rapid
fatigue.
In the "autocrate," novel French
touring map, the road being travelled
is shown upon band OF paper, which
is mounted on the dashboard of the
motor-car, and by automatic unroll-
ing indicates the exact position of
the car at any moment. 1t is es-
pecially useful at night, while at
present high speed sign boards are
not easily read even in daytime. The
scale of the map is sufficiently large
to make clear the exact point of the
route reached, and the chauffeur can
read ahead for five miles, thus being
able to fix IN mind all obstacles,
turns, descents, etc long before they
are reached. At night the chart is
always lighted.
The peculiar substance known as
asbestos, which was regarded as value
less century ago, is now in demand
for many purposes. 1t is made into
roofing felt, cement, theater curtains
and various heat resisting articles,
and has been recently spun into a
light and fairly strong thread. Even
ropes, with or without steel cores,
are made from it for iiremen. A new
and rather surprising application is
for army stockings, which have been
shown to be less irritating to the feet
of soldiers on the march than other
stockings, and the war department of
Austria is considering their general
adoption.
About ten species of vegetable
sponges" are now cultivated in the
warmer parts of Africa and Asia, es-
especially in Algeria. The fruit is
edible before maturity, but on ripen-
ing the pulp separates from the
fbrous material, which then becomes
an excellent substitute for real sponge
for the toilet, bathroom and many
other purposes. The Algerian sponges
are in large demand in Paris.
Fog dissipation by electric dis
charges has proven more effective
when the fog contains dust or smoke
than when it is water only, the solld
PARTICLES seeming to become charged
and to be then repelIed, precipitatlnl
PARTICLES of vapor with which they
collide. With a bundle of spikes a!
radiator, a space of some yards car
be cleared in few seconds.
Why the teeth of some people deca!
early while those of others continue
sound throughout a long life Is
problem that appears to have beel
only imperfectly solved. A European
Investigator, DR.. &. Risa, has latel!
analyzed the saliva of 219 children
averaging IL years of age, and ha
confirmed the idea that there is
relation between the alkalinlty OF tn
saliva and dental carries. A highl.
alkaline saliva ensures good teeth
He has made many experiments t.
determine how an acid or slight