The Indianapolis journal. [volume] (Indianapolis [Ind.]) 1867-1904, 1898-07-24
SCIENTIFIC.


reports of museums in America are always
interesting, those prepared in England are
of no use to anybody.
To increase the durability of limestones
used for Buildings, a French engineer pro-
poses to coat their surfaces with solution
of hydrate of baryta, which is finally con-
verified into barium carbonate or sulphate,
both of which are hard and irrsoluble.
The British army is accused of playing
considerable part in the destruction of birds
by requiring it's officers to wear plumes. 1t
does not appear that the use of plumes is
likely to be abandoned; but substitute for
the so-called Osprey" feathers may be
sought.
"A recently described aerial graphoscope
consists of a latch rotated about it's center
in its own plane. A picture projected by a
magic lantern upon the rapidly moving
strip of wood is made to appear unbroken
through the persistence of vision. which
may be tested quantitativeIy by his APP
paratus. 1t is suggested that stage effects,
such as the dagger in Macbeth" may
be produced in this way.
The plan of Herr Carl Wegener for avoid
ing smoke consists in the use of pulverized
coal and a special feeder which Sits the
dust over the entire fire, causing it to be at
once inf1amed without smoke and with very
little ash. This also effects a considerable
saving Of fuel and opens way for utilizing
the waste coal dust of mines and storage
places; but on the other hand, it makes
grinding necessary when dust from other
sources fails.
In new method of porcelain manufac-
ture, the clay, instead of being worked cold,
upon potters lathe or pressed into mold,
is finely ground, then melted in an electric
furnace at about 3215 degrees Centigrade,
and poured into a heated fireproof casting
mold Glazing is usually unnecessary. An
advantage, in addition to reduced cost, is
prevention of shrinking in cooling, and the
inventor expects to make the cooled mass
malleable. An unconquered difficulty is col
ored decoration
SO marked an effect is produced upon the
eyes by heat that the term cheat cataract
has become well understood. 1t is known
that many glassblowers develop cataract
before the age of forty, and a German ply
stefan, DIR. HirSchberg, has just reported
finding five victims of the disease in a crew
Of thirty men employed in a glass factory.
The idea that cataracts are most common
in hot climates is confirmed in India, where
persons of forty are often affected, al
though in cooler lands SiXty-tWo is the
average age for senile cataract to appear.
new kind of carbon for arc lamps is
reported to have been patented in Russia.
1t is made from 80 per cent. of very pure
carbon and 10 per cent. of carburet of sill
cium, the ingredients being very finely pull
verified and agglomerated with pitch. The
carburet of Silicium contains no volatile
element and resists oxidation more than
other substances, the carbon being neceS-
sary to make it a conductor. 1t is claimed
that the duration of these carbons is 800
hours, and that they not only save % per
cent. in current but yield rcher-tinted
and stronger light than that of ordinary
arc lamps.
The aluminium of which they are con-
structed is not the only novel feature of
two steam launches that have been built
for the central African expedition of Maj.
A st. H Gibbons Each vessel is twenty
eixr faa ord v;1 nd hole
consisting of seven sections weighing about
one hundred pounds each; but on reaching
a large body Of water the navigator may
combine his two vessels into one of length
of thirty-Seven feet by removing the two
bow sections Of each and riveting together
the remaining five sections of each. A
barge may be made by boiling together the
bow sections from the two vessels
Acetylene gas can be made to yield from
three to four times as much SCOT is
obtained from the same quantity of mineral
oil. and the product is much superior to
ordinary lampblack. being free from tarry
and other Objectionable substances. Acety
lene black is very bulky and especially
adapted for India ink, as well as for inks
for printers and photographers In one OF
three methods of manufacture patented in
France by M. Il. Hubon, the gas is kept
/ in a steel cylinder under pressure of two
atmospheres and ignited by an electric
spark or glowing platinum wire, the pres
sure of the resulting hydrogen which the
cylinders must resist Delng not more Jnan
twelve atmospheres. This method gives the
theoretical yield of carbon.
There are several kinds OF animals, points
out Cosmos, that have never swallowed
water. Among these are the lIamas of Pata-
/, gonia and certain gazelles of the far East.
and a considerable number of reptiles-ser-
penis, lizards and certain batrachians-that
live and flourish where there Is no moisture
/ Al kind OF mouse Of the arid plains Of west