The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1898-01-23
SCIENTIFIC.

Sodium carbide as described to the Paris
Academy, is an inexplosive white powder
which, on slight heating, burns in air, leay-
ing sodium carbonate. Its chemical actiV-
ity is much greater than that OF calcium
carbide.
The high quality of Swedish steel was
strikingly illustrated at the Scandinavian
exhibition. A steel ribbon, cold rolled, was
twined like silken band about one of the
pavilions, the length Of this monster tape
being 1854 feet its width eight inches and
it's weight 1,146 pounds.
The Borchardt automatic pistol is cited as
an example of rapidity in complicated me-
chanical movements. AS eight shots have
been fired in one-third of a second one
twenty-fourth of a second must suffice for
advancing the firing bolt, exploding the
charge, extracting the cartridge and reload
ing and cooking for the next shot.
Selenium, hitherto chiefly an interesting
curiosity of the chemists laboratory, has
been recently used for coloring glass. When
added directly to the glass in the melting
pot it gives a fine rose tint, varying some
what with the purity of the selenium and
the hardness of the glass; and when the
selenium is mixed with cadmium sulphide a
beautiful orange red is yielded.
Illumination or cud-chewing in man, ac-
cordlng to M. Nattan-Larrier, is not known
to be, as has been stated, chiefly found in
males. 1t may be hereditary, and when in
voluntary is especially prevalent among
nervous dyspeptics. 1t is not associated with
special chemical change of saliva or mall
formation or lesion of stomach or oesoph-
agus When voluntary 1t usually occurs in
the weak-minded, but in children 1t may be
initiative. Some idiots bring their food up
at will for rechewng after retaining it for
hours.
The new rust-preventing paint of DR.. B.
Kossmann, of Charlottenburg, Germany, is
composed of the peroxides of earths Of the
cerium group. These are incorporated with
HnSeed oil VarniSh, with the addition of a
drier of linSeed oil boiled with a mixture OF
boric acid and the peroxideS. Graphite,
lampoiack, heavy spar, ETC., may be used
for coloring. The paint is claimed to fulfill
all requirements, having sufficient oxygen
to insure hardening of the linseed varnish
with freedom from any metallic base cap
able of causing rust by setting up an cleo
trio action with iron.
A new method of etching on glass or por-
celain has been patented by Herr Retzlaff,
of Berlin. The usual German process con-
sists in cementing a sheet of tinfoil to the
surface, which is then uncovered for etch-
ing by a skillful cutting out of the pattern
in the foil and washing away of the cement.
The improved plan is to perform this opera
ton more simply and perfectly by chemical
means. The pattern is printed or stenciled
in grease colorS on the tinfoil, which is then
fastened to the glass by asphalt and the
prepared plate is placed in an acid bath that
dissolves out the exposed parts of the foil.
glass is ready for etching in the usual way.
BY means of the microtome, slices of vege-
table and animal tissues down to thinness
of about one-ten-thousandth of an inch are
obtained for microscopic study. Prof Ell
mer Gates, of Washington, has now gone
further, and even slices up blood cells and
microbes by cementing them in q single
layer between two glass slides and cutting
the slides apart with very thin blade of
copper sharpened to the highest possible de-
gree. The fine grain of the copper causes
it to take an edge that no razor can APP
proach. The cells are again cut by repeat
ing the operation, and it is claimed that
slices have been made only one-hundredth
as thick as the thinnest produced by the
microtome
Since the domestication of the zebra it has
been suggested that mixture with the
horse would give half breed combining
the qualities of the two animals, the
mule combines the horse and the ass. The
new hybrid is announced by the Baron De
Parana, the animal being now in the Sec
ond half of its first year. The "zebroid,"
as 1t is called is male of bay color,
with Zebra-like stripes, which are hidden
on the body by the thick winter coat. The
black name resembles that of the zebra,
the tail being like mules. The haunch
Is large and well rounded. the chest long
and high, the eyes and nostrils are large
the lips and head small, the legs muscular
but delicate, and the hoofs small, black
and hard. The creature is very lively, but
gentle.
From experiments by N. Ravel it appears
that 6S5 cubic feet of acetylene gas gen.
crate in the gas engine one horse power
per hour. which is reduction in fuel of
two-thirds as compared with petroleum.
The mixture of air with acetylene begins to
be explosive when the proportion reaches
l3o parts of gas to one of air, while the
explosive force reaches its maximum with
twelve volumes OF air to one of gas, and
disappears at twenty to one. The flashing
point is about 800 degrees F., most other
gases used for power requiring a temporal
ture of 1100 degrees to ignite them The
temperature of combustion is much higher
than that of other gases. Great rapidity
of the transmission of flame, low ignition
temperature high combustion temperature
and extraordinary energy of explosion are
therefore the special characteristics of this
gas.
Civilizations advance is responsible for
remarkable change of habits in more than
one wild animal. A familiar instance is
that of the kea, the great New Zealand par
rot, which was formerly esteemed as
friend of the farmer, but which has become
a dreaded scourge on account of it's acquired
taste for the kidney fat of sheep DR..
Schonland mentions the chacma baboOn as
a Cape Colony animal that has become sim
llarly transformed. 1t has taken to killing
lambs for the milk with which they have
filled their stomachs, and it is increasing
to an alarming extent on account of its
wariness and the protection and natural
food afforded by the disappearing prickly
pear. Another South African example is
the so-called "wet-gat spreouw (Spreo BIZ
colOr) This animal is now very destructive
TO fruit, which few years ago it was never
known to touch, it's food consisting chiefly
of insects. The Maanhaar jacl1al seems to
have partially acquired a new liking. While
its ordinary food is insects and DR. SchOn-
land has been unable to find anything else
in it's stomach, farmers in certain districts
possibly where man has reduced its food
insist that it is very destructive to small
stock.
SHREDS AND PATCHES.