Cincinnati daily press. [volume] (Cincinnati [Ohio]) 1860-1862, 1861-03-09
sC1RNTfFTo ann mRCHANfoAL ARTs.

| RfoOves-thts being considered by some the
Objectionable feature in this celebrated cam
non A solid iron shot can not be turned,
or, rather, returned, 10 any offensive use un-
less IL happen to fit the bore of any hostile
cannon most exactly. The leaden jacket or
coating, is, however, necessary TO the Arm
strong plan ofriiliBg.
The Armstrong guns are made Of fiat bars
end fiat rings Of wrought iron twisted and
welded together. The Whitworth guns are
made out of homogeneous iron or steel-that
is, iron run from crucibles into molds, 30 as
to form one solid, compact homogeneous
mass. Both runs are breech leaders, both
have a direct passage through from breech to
muzzle, and both breeches open and close by
means OF levers and screws. In the ARM
strong gun the breech- piece is small and
movable, and there may be any number
ready to replace a lost OF damaged one. In
the Whitworth gun the breech piece is
heavy, and opens ciumsily on a hinge, so as
TO be quite in the way during loading, aud
liable to accident. Injury to the breech
would be for the time ruinous to the gun.
This hinged breech is considered the weak
point in the Whitworth gun. Homogeneous
iron is better than welded iron bars and the
even bore and solid shot are far better than
the lead. coated shot. 1t requires a power of
meny tuus weight to force one of Arm
stronR's lead-coated shot through from
breech to muzzle but any child NAV easily
push one of the Whitworth shot through his
guns, the fit is so true. even and easy. The
Armstrong gun can not be used as a muzzle-
loader; tue Whitwerth gun can be so used
if required. A Whitworth ball will pass
through forty feet Of sand, and continue in a
direct line at any angle through water; the
rifle bullet has a range OF 1000 yards.
STEAM VERSUS FmE.-At a fire which
broke out recently in a large caudie-man-
u~faciOTy in Paris, the flames were quickly
subdued by steam, generated in the ordinary
boilers of the establishment, and directed to
the burning portions of the building by
tubes prepared for the purpose in case of
Emergency. A vast quantity of valuable
property was thus saved, and the matter has
since been the topic of lively discussion
among the scientific men Of France.
This method of ~extingnishing, or rather
sitting fires is, however, not new. It was
first applied in 1887 by a citizen Of Lille, who
proclaimed his theory, but met with little
encouragement. He justly maintained that
q + being the sole element ofcombustion, the
! bare act of sitting the current must be suf-
ficient to extiUguish flame; and nothing was
= better calculated TO effect this than the light
> elastic vapor generated by steam, which, ex-
, GLIDING atmospheric air, takes its place and
) at once arrests combustion.
8 In lS40a burning cotton factorya at Amiens,
was saved in this manner, and in 1852 the
French distilleries were provided by law
NAAh EblNNl ny me- GbNhh II Ndok
q quantities could be brought to bear on every
/, department of the building. The dimen-
= sions of these tubes are prescribed by law,
and are in every case to be sufficient to com
: bat liquid fire produced by alcohol in case of
ignition.
5 The importance of this discovery will be
I apparent to every one engaged in mauufac-
turing pursuits. They have little to fear
) from fire who provide their factories with
} those safety tubes, and with the portable
apparatus by which the steam can be elected
, at will into any desired apartment. So i'm
p~ottant is this discovery deemed in France,
that the Minister of Marine has given orders
to apply it to the steam vessels now lying at
, ToulOn. Unsuccessful, it will be applied to
all the steamers of the French navy, and
ultimately to Atlantic and other passenger
steamers; nor is it at all likely that France
will long monopolize this simple fire anni-
hilator.
THE ZINC OF COMMERCE AND ITS UsEs.-
The principal localities where zinc is found
are at Tarnowitz, and other districts of
Upper Silesia; at Raibel in Poland, and
B'eiberg in Carinthia; at Limburg in the
Netherlands; at Altenberg, near Aix-la-
Chapelle; in Derbyshire, &c, England; in the
Atari mountains, Russia in New jersey,
Virginia, and some other parts of the United
States. The calamine-carbonate of zinc,
and the electric calamine. or silicate of zinc,
are prepared LOT TeuucLlOn Oy breaking the
ore into small fragments, separating the i'm
purities 90 far as possible, and.then calcin-
ing, either in a kiln or reverbeIating furnace.
When the latter method is employed, the ore
is frequently stirred about with an iron
paddle, by which a fresh surface is con
stantly exposed to the action of the heated
g8ses of the furnace. By this treatment the
water and carbonic acid of the mineral are
entirely expelled, aud at the close of the
operation, which usually lasts from five to
SIX hours, the charge is raked out and al
lowed 10 cool. The prepared ore is then
mixed with about one, seventh of It's weight
of powdered charcoal, and is reduced to the
metallic state in vessels specially adapted
for this purpose.
EcoNoMY OF SPACE IN STEAM ENGINEs.-
Invention with regard to the steam engine
has of late years been largely directed to
the economy of space. The tubular boiler
is one of the contrivances to that end, offer
ing, within the same bulk, q greater surface
to the action of the heat on one side, and of
the water on the other, than any other form
OF boiler. In marine engines this economy
of space has a special value and Importance;
and the direction which invention has taken
with a view to this economy, is shown in
the numerous expedients for the direct
action of the piston rod upon the crank of
the psddle-wheel or of the. screw propeller,
without the Intervention of the beam. A
rotary Steam engine, if one could be con-
trived, whose rubbing surfaces were perfectly
~steam-.ight and durable, would effect a re-
maTkable economy of space, and would, it
is believed, be better calculated than any
other to drive a steam. propeller. This is a
problem more likely TO be solved, now that
a gain of power is no longer looked for from
the use Of rotary engines, but only a simple
and more convenient mode of applying it.
GLAZING PAPER. When paper is required
to be glazed il is effected by passing it be-
tween polished and heated cylinders, in
passing through which it is subjected to
the most severe pressure. The effect of this
and the heat is TO produce a very fine aud
smooth surface. The paper is then readyfor
any of the varied purposes to which it is to be
applied. It is a curious fact that the friction
used in glazing paper between cylinders
develops so much electricity that a doctor
blade is necessary to detach the paper from
the cylinder, to which it would otherwise
closely adhere. II will be obvious that by
mixing any substances, such as gelatin,
starch or eoloring matter with the pulp, the
color and quality of the resulting paper is
affected accordingly. The finer kinds of
psper are impregnated with gelatin or size
aIer the paper is made. 1t has been found
that mixing the gelatin with the pulp in the
process Of manufacturing Injured the felt
used in the machine; and it has, therefore,
as far as possible, been accomplished out Of
the vat.
PURIFYING Foul WATER.-Mr. Spencer,
the well known English chemist some time
since experimentally ascertained that the
magnetic oxide of iron, which abounds in
rocky strata, and in sands, &c. attracts
oxygen, whether it exists in water or in air,
and p~olarizes it; that this polarized oxygen
is the sslnbrifying ozone, and that this ozone,
so formed, destroys all diseoloring aud pol
luting organic solutions in water, and con-
verts them into the sparkling and refresh
ing carbonic acid Of the healthful spring.