The Colfax chronicle. [volume] (Colfax, Grant Parish, La.) 1877-1981, 1888-10-20
SCIENCE AND INDUSTRY.

oOseNSe AMI tNOOSiUS'
Steel, when hardened, decreases In
specific gravity, contracts in length,
and increases in diameter.
There are 150, 900 miles of rail-
road in the United States, or about
half the mileage of the world. They
have cost So, 900. 900. 600. and employ
more than amillion persons.
"A Midtown, Me-, mechanic has in
vented log-sawing apparatus which
has an upward as we'll as downward
motion. The scheme has not been
fully tested yet, but, if successful. will
be great time-saving invention to
.umber dealers. ass M
There is about one pound OF iron
In the blood of seventy-five men, but
small as is the quantity-about one
hundred grains in each mamie could
not live without it, and he ought to
get it from his food, which obtained it
from the earth.
Attention has Just been called in
scientific paper to two races of men
that must soon become extinct. 1t Is
confidently predicted that at the pres
emit rate of decrease the Maoris of New
Zealand, now reduced to less than A.
900 men. from 100, 900 in Captain Cooks
days, must have disappeared by the year
1000. The Laplanders are estimated
not to exceed $4,000 in numbers, and
are gradually becoming fewer.
Following the disappearance Of the
upper limb of the suns disk at sunset,
there has been observed the phenome-
non of a beautiful green ray, its fash
being as rapid as that Of lightning, and
only visible under rare conditions of
clearness of the sky. The explanation
offered for its appearance is that of tho
simultaneous contrast of colors, the
theory propounded originally by M.
Chevreul.
The frequent need Of diffusing light
in the studios of photographers, either
from the direct rays of the sun or from
the reflection OF colored light from high
buildings, is we'll known. Waxed
paper of the tissue sort, Is now be-
lieved to be one of the best mediums
for this purpose, since it allows large
percentage Of light to pass, the latter
being at the same time equally 6iffused.
Pictures may this way be made as
quickly as if there were no medium in
terposed.
Experiments made by electricians
seem to demonstrate that the atmos-
phere, when free from foreign matter,
can not hold electricity, nor serve as a
conductor. The floating particles Of
dust are, it would appear, an impor-
tant element in the phenomena of
thunder storm, the passage Of which.
always leaves the air 80 clear and clean.
The peculiar danger from lightning in
manufacturing town, with its smoke
laded atmosphere, seems thus to be
scientifically confirmed.
"A highly important industry is
springing up in the United States, that
Of '.muszling" oysters, by which they
can be sent long distances in their
shells with perfect safety. Until re-
Gently, the general practice was to
pack the raw oysters in ice, but sud-
den rise Of temperature is liable to
render whole weeks supply useless.
Oysters feed twice day; and never
open their shells except at feeding
time. When taken out of their natural
element, they attempt to feed at regu-
lar intervals, and so soon as the shells
open, the liquor they contain Is al lost,
the air takes its place, and the first stage
of decomposition sets in. AS long as
the shells are closed. the oyster Is
fit to eat; it feeds on the liquor in the
she'll, and will thus keep in good con-
dition for considerable time. To Sc
cure the keeping of the shells closed.
a method has been invented of tying
C'muzzling'') them with a stout wire,
which can be done with great rapidity,
and now arrangements are being made
for dispatching American oysters in
their natural condition all over the
civilized world.
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