The herald and mail. [volume] (Columbia, Tenn.) 1873-188?, 1875-03-19
CURIOUS AND SCIENTIFIC.
Or all metals known, silver is the be

| copal varnish, they can be washed with
cold water without injury.
To cement metal to glass, mix two
parts powdered white litharge and one
part dry white lead into a dough with
boiled linseed oil and lac copal. The
metal is to be coated with the cement
and then pressed upon the glass.
A RECENT test of the relative strength
of oak and Oregon pine, made at San
| Francisco, with bars each one inch
square and three feet long, showed that
| the pine was equal to the oak. Both
broke under the same weight placed in
the middle of each bar, namely, 26O
| pounds.
THE MARTIAL SEAs.-M. Meuuier has
recently advanced the theory that the
planet Mars is much older than the
| earth, because of the ratification of its
| atmosphere and the small extent Of its
seas. The form of the latter, he says,
is exactly that which the terrestrial
oceans would assume after partial alb
sorption by the earth's crust. If, for
example, the Atlantic were absorbed SO
that only that portion included in the
contour made by the uniform depth of
u, 900 feet were left, the shape would
be exactly similar to that of some of
the seas recognized in Mars.
EXTENSION OF UNDERGROUND RAIL
WAYS IN LoNDoN.-At the enormous
cost of $12, 500, 900 the Metropolitan
Inner Circle railway company is busily
engaged in carrying out its plans. In
addition TO the construction of lines,
stations, ETC., this company in COM
PEELED to make an entirely new street
from Fenchurch street to King William
street, and also to widen the streets
right and left which branch therefrom.
The importance attached to this enter
prise may be gathered from the fact
that the metropolitan board Of works
and the corporation of the city of Lon
don have subscribed the sum of $2,-
SOC, 600.
A New USE For MINERAL OILs-Tn
a late number of the Australian Medical
Journal, DR.. John Day maintains that
certain mineral oils, gasoline especially,
are of great use as disinfe Giants, their
value depending, he believes, on the
fact that they are rich in peroxide of
hydrogen. He employs the gasoline in
various ways as disinfeetant, applying
it to walls, to articles of furniture and
to clothing also, as wash for the
hands after treating infectious diseases,
allowing the moistened hands to dry in
the open air. A peculiar and valuable
property of these oils as disinfectants
is their continuous action, while they
improve and gather force by exposure
to the air.
No Coal IN CALIFORNIA DR.. j. @.
Cooper, who has made the most careful
Io4@ 4ha4 10
logical facts are all against the pr0ba-
bility of the existence of any true coal
measures in California. In ninety-nine
cases cut of hundred, the alleged coal
discoveries are of no value whatever.
In other countries, the true coal of the
carboniferous rock is formed of tree
ganizatiou. None of these remains are
found in California, but in their stead
are found the remains of cOniferous and
dicotyIedonous trees, or those having
double-Iobed leaves, the beds in which
they are found being classed by geolo-
gists as lignites. In some parts of the
quantities, and may be employed, like
peat, for local consumption.
SAGACITY OF THE PARTRDGE.-In-
stances of the sagacity of the partridge,
wOodcock, and other birds have often
been related. But the most singular
illustration of the deception pracsiced
by the first OF those willy species to pro-
tect their young is given by Mr.. Hen
shaw, of the government survey west
of the one hUndred.h meridian. While
riding through pine woods, brood of
cartridges, containing the mother and
eight or ten young of about week
old, was come upon SO suddenly that
the feet of the foremost mule almost
trod on them. The young rose, flew a
few yards, and, dropping down, were in
an instant hid III the underbrush. The
mother meanwhile began some peculiar
tactics. Rising up, she fell back again
to the ground as # perfectly helpless,
and initiated the actions of a wounded
bird so successfully that for moment
it was thought she had really been
trodden upon. Several of the men,
completely deceived, attempted to catch
her, but she futtered away, keeping
Just out Of reach of their hands until
they had been enticed ten or twelve
yards oft, when she rose and was of
like bullet. Her tactics had success
fully covered the retreat of her young.
CUTTING F11Es.-The exactness and
skill shown III file cutting attest the
dexterlty that can be reached by con-
slant practice. Files are cut by hand
and by machines, but the latter have
not achieved any greater regularity or
precision than those cut by hand, and
by many artists the machine cut files
are considered inferior. The expert
billiard player makes countless false
strokes but none of the errors remain
on the record-they perish as soon as
made. But the file cutter work lives
after him. The blanks, as they are
technically called, are steel strips in
the shape CT flies, and the teeth are
raised upon them by small chisels,
held in a peculiar way and struck by
hammer. The frequency of the teeth
is determined by the force of the blow,
which raises a furrow in the blank
the chisel is then slipped along until it
strikes the back furIow, and another
blow is given and SO on until the file
is completed. The whole process is as
rapid in the hands of an expert as
writing, and goes on continuously from
morning till night with no cessation.
An uneven blow does not destroy the
file, but injuries the workmanlike 9p
pearauce. Any one who examines the
files of commerce will see their reg
ularity. Some files are so small that
they will fl 1at in water, being little
over an inch in length. They vary
from this size to thirty inches in length,
the latter being used in the heaviest
machine and steam engine works.