The Bossier banner. [volume] (Bellevue, Bossier Parish, La.) 1859-1952, 1889-03-07
SCIENCE AND INDUSTRY.


naphthaline as wood preservative.
1t is said to be very effective, leaving
the wood dry and with only faint
aromatic smell.
The Austrians are constructing
portable electric-light plants to be
used in entraining and detraining
troops at night, and the Germans are
going to have similar portable plant
attached to their siege trains.
The saving which will result in
substituting electricity for horsefesh
on the street railways of this country
is limited at by the fact that the opera
tion of one street railway in England
by electricity will result in saving $780,
900 per annum over and above the
present host of operating it by horses.
"A Swedish scientist claims to
have discovered the secret of petrify-
ing wood by artificial processes. He
thinks it will be possible ere long to
construct edifces of wood and convert
them into stone. As it takes three
months and costs about $500 to petrify
block of wood of the dimensions of
one cubic inch, it will probably be
some time before his process will be
generally adopted.
The curious fact has been demon
strated by Sir John Lubbock that
certain kinds of ants are unable to
exist without keeping other ants as
slaves, though why this is SO he has
not found out. On removing the slaves
from nest of fifty slave-holding ants
he found that the latter Immediately
commenced to die off, and were speedily
reduced in number to six. When the
slaves were returned the mortality
ceased.
According to Engineering, some
experiments conducted at the Ports
mouth (Eng,) dockyard, with view
to determining the resistance of metals
at different temperatures. indicate that
the strength of iron increases uni
formly up to 500 degrees F., while the
ductility diminishes up to about 800
degrees; it then increases until some
what higher temperature is reached,
and then remains nearly constant up
to temperature of nearly 500 degrees.
Steel, similarity tested, showed no
diminution of strength up to 500 de-
gress, but at this point its ductility was
reduced one-half.
"A new Partisan industry is the
manufacture of hoar-frost glass, which
is covered with feathery patterns re-
sembling those naturally produced
upon window-panes in cold weather.
The glass is first given ground sur
face, either by the sand-blast or the
ordinary method, and is then coated
with soft yarnish. The varnish con-
tracts strongly in drying, taking with
it the particles of glass to which it
adheres, and this reproduces very
accurately the branching crystal of
frostwork. A single coat gives deli
cate effect, and several coats yield q
bold design.
"A lecturer in the Royal Institution,
London, attempts to ''defne poison ac-
curately'' as follows: ''Any substance
which otherwise than by the agency Of
heat or electricity is capable Of destroy
ing life either by chemical action on
the tissues of the living body, or by
physiological! action after absorption
into the living system" The fact
would seem to be that ''poison" is a
question of quantity, not quality. Very
small quantities of aconite. hydro
cyanic acid, etc., suffice to destroy life,
but used in limited quantities they are
valuable drugs. One well-known
definition of poisons is substances
which derange the vital functions and
produce death by an action not me-
chanical."
"A curious Photographic apparatus,
in which camera is raised by "a rocket
and lowered by parachute, is being
developed by French inventor, M.
Amedee Denisse. In its experimental
form the cylindrical camera has twelve
lenses round its circumference with a
sensitive plate in its center, and is pro-
vided with a shutter which opens and
instantly closes as the apparatus COM
mences to fall. The descent is eased
by the opening of the attached para
chute, which is drawn back to the
operator by cord attached before the
firing of the rocket. For securing
bird 's-eye views the photo rocket offers
several important advantages over
balloon photography. such as compare
tive cheapness in operating and free
dom from risk in case of use for mill
tary accommodating.
1t Seemed Very Funny.