Evening star. [volume] (Washington, D.C.) 1854-1972, 1873-01-25

"
under ordinary circumstances. are properties
which fit IL to form the most perfect of ali
springs; so that If we wish to store I'M TO rer
ard yet re tain the ability to lberate IL Suddenly
ard completely, air places the means of doing
so at our disposai Like many other srientifc
facts of deer import this " as first discovered hy
school boys, and embodied in the pcp-gan-a
poweTless Instrument We ordinarily see IL
hut one capable OF intiicting severe blow when
well made and properly used. We have seen a
well made pop-gun sink a Il aden bullet its full
depth into pine board, feat which very few
men could accomplish by projecting such mis-
sile by the unaided arm. From the pop-gun TO
the air-gun proper was but step; and as this
weapon has recently attracted good deal of
the popular attention, and as the ideas that gem
orally prevail respecting IL are exceedingly erru-
neous detail of a few we'll ascertained facts i'm
regard to its operation and effects may not be
out of place.
OF the various notifications of the air-pun
that are used at fairs and in shooting galleries
for boys, we do not propose to speak. They are
i'll general powerless except for the projection
of peculiar feathered darts, which are entirely
Inefficient at a distance Of one hundred PAGES:
whereas the true air-gun will send its bullets
with a force which at this distance viii prove
fatal to any small animal, and even to man HIM
self.
In the air-gun proper. the expansive force of
compressed air is substituted for the exhaustive
force of gases liberated by the combustion OF
chemical compounds, as is done i'm the ordinary
musket and pistol; and it is obvious, that. with
the exception of single feature, there is nothing
by the action Of compressed air as by the action
of gunpowder. This special feature consists i'm
the reduction of temperature, and consequent
loss OF expansive force, which all gases sustain
of the air-gun is rapidly filed with condensed
air by. means Of the air-pump, it becomes
exceedingly warm. This heat has been ex-
tracted from the condensed air; and, when the
latter is allowed to cool and then to expand, it
falls as far below the regular temperature as IL
rose above it when compressed. Upon this
principle, water may be frozen by mechanical
action; and indeed, there are ice machines now
in existence that work upon this plan. 1t is
evident that this feature places a limit upon our
power OF uti zing the expansion of air, although
it is not probable that this limit will ever he
reached in practice. We must also remember
that this defect is in measure compensated by
the large size of the reservoir of compressed air.
In ordinary fire arms, the powder occupies but
asmall portion Of the bore of the gun, and must
expand SO as to I'LL the whole barrel before the
charge leaves the muzzle. In the ar-gun, the
force throughout the whole length of the bar
rel and hence the high velocity Impaired to the
ball by means OF a comparatively slight initial
pressure. The ordinary initial velocity of
bullet from from good air-gun is from 100 to
800 feet per second, that Of a rifle bullet being
! 800 to 800 feet in the same time.
But with well-made guns, furnished with
velocity as high as 900 per second NAV he
reached. Air-guns of this class have assumed
an almost infinite variety of forms. The original
and which is figured in most works on natural
philosophy, was made in the form Of fowlnp-
piece, with a cObble globe attached for holding
the compressed air. The modern air-gun, how
ever, Is generally in the form of a walkiDg-cane
and, as this kind of weapon does not recoil at all
under ordinary circumstances, there is no neces-
sity for the firm and pOnderOus stock which is
requisite for most firearms. Indeed, so slight
is the recOil that the weapon is in most cases
actually pressed against the cheek, and aim
taken in this manner. As We shall see hereafter,
paratively slight projectile force Of the weapon,
and not so much to the peculiar action of the
elastic fluid used The force with which
the ball is propelled depends, OF course,
upon the extent to which the air is COM
pressed in the chamber; and hence one
of the parts upon which the efficiency of the
weapon chiefly depends is the condensing- pump
In selecting pump, most persons make the
mistake OF suppOsing that the larger the pump
the more powerful it must be, whereas exactly
the opposite is the case. A pump with bore of
one-quarter Of an inch is just sixteen times as
pOwerful-that is to say, it will compress air
sixteen times as effciently-as pump one inch
in diameter. With pump having bore OF one
fourth Of an inch, it is easy for an ordinary man
to cOndense air until it exerts pressure of 2,5GO
pounds on each square inch of the vessel I'm
which IT is contained. Air at this pressure is,
however, very difficult to confine. Not that
there is any danger of the small steel holders
bursting, for this is not at all likely to happen;
but the valves must be very well made and of
very excellent material. II this degree Of con-
densatiOn be obtained, and the rest of the
weapon be well made, a bullet may easily he
sent hlOugh a twO-nch pine plank at one hun
dTcd yards Such a projectiie is capable of in
ficting fatal wound at two hundred yards.
Probably the most perfect air-guns in the
world are those made in London for the use of
English pOaehers. AS they make no smoke, ami
consequently no smell, they are not 70 easily
detected as firearms when used in game pre-
serves. 1t Is a mistake, however, to suppose
that they make no noise. When charged so
to produce the effects above described, the re-
port Is quite sharp-fully as sharp that pro-
duced by gunpOwder. When lightly charged,
the report is of course diminished; but the force
with which the bullet is projected is also pro-
pOrtionally lessened, and so is the recoil. As a
weapon for secret assassination, therefore, the
air-gun does not possess much advantage over a
good rihe-cane. Few persons are, however,
aware of the slight charge Of powder or air that
Is necessary to produce a fatal wound at short
bullet that will go through half
inch board will kill man if it strikes
him in vital and not too well protected
part. Now, bullet can be projected from a
rifle with q force sufficient to pierce such board
not greater than that which will lie on silver
three cent piece; and provided the charge be
ignted quietly, as by pill lock, the noise Of the
explosion will not attract the attention of per-
sons who are sixty yards distant. The small
pistols in common use make very little noise ex-
cept when discharged in confined places and
yet if the bali should strike a vital part, death
may be caused instantaneOusly by wound
from them The only advantages possessed by
the air gun are Its perfect cleanliness, and the
fact that the parts are not liable to be cOrroded
and rusted. 1t never requires cleaning; but the
labor Of charging the condenser may be fairly
offset against the labor involved in cleaning or
binary Firearms after they have been used.-Ip-
dustyIal Monthly