The Abbeville banner. [volume] (Abbeville, S.C.) 1847-1869, 1857-04-09
From the Scientific american.
THE BURNING OF GUNpOWDER.

There are some operations so slow as to
challenge the highest effort of the imagina.
ton. Such are some of the changes reveal
ed to us by geology. There are others so
extremely rapid that their division into
successive steps becomes still more difficult.
In this last class may be included the sue
cessive ignition Of each grain in charge
of gunpowder. 1t is in one Of those sub
jccts difficult to reduce TO experimental
fact which, were it not sufficiently obvious
of itself, could be readily proved from the
diverse opinions expressed by savans who
have investigated the question connected
Herewith.
Professor Treadwell, of Cambridge, has
within few months published paper on
the construction Of n large cannon, in which
he concludes that it is possible and perfect
ly practicable, with our present means and
materials, to construct large cannon
which will throw balls to a very greatly
increased distance. lie proposes to do this
by shrinking hoops upon the guns, form
Of applying the material which would Ger.
tainly increase the effect of the exterior
layers Of metal, although it would tend to
increase the crush, and contribute to the
disintegration of the interior particles when
the explosion Of the charge occurs.
But we recurred to that paper mainly
for its graphic description of the process of
firing which is as follows:
"Count Rumford has proved that the
burning Of the grains is slow, or that sem
s'ble time is required with each grain be.
fore it is wholly converted into the gaseous
state; and various experiments made in
England and in Prussia have shown that
there is no sensible difference produced in
the velocity of the shot by communicating
the fire to the centre rather than to one end
Of the charge, which ought evidently to
take place If the fire is communicated from
one grain to another in succession, rs this
communication, being in both directions
when proceeding from the middle, would
require but half the time that is required
when proceeding from one end, and ought
10 produce sensible increase in the velocity
Of the shot.
think therefore that these two facts
"ar"a": :!:c following inference ne tc the
course Of the action during the production
Of the force. When the fire reaches the
charge from the touch hole, the nearest
grains become kindled, the hot fluid evolved
is thrown further into the charge, and the
burning succeeds successfully until the
pressure becomes so great as to condense
the air contained between the grains suf1i-
cientIy to produce the heat required for
firing those grains, which are then consum-
ed more or less rapidly, as they are fine or
coarse. We have, then, first the burning
in succession of a small part of tie charge;
then the immensely rapid, though not in
stantaneous, kindling Of every grain com.
posing it; and then the consumption of
those grains, which is not accomplished
without time. 1t is task for the conccp-
ton to grasp these events, following one
another in distinct succession, each having
its beginning, middle, and end, and all be-
ing comprised in the period of l,20Oth of
second (gun feet long formula t. 2s
plus y. When we have mastered the i'm
agination of these. we may 60 further and
combine with them the connected and con-
temporaneous action of the ball, which pas
ses from rest to motion, and through every
gradation Of velocity up to 900 feet Sec
ond, and leaves the gun as our historical
period of 1-20oth of a second expires"
We may add that the formula does not
apply exactly, and the time during which
the powder burns proftably is, consequently
less even than the Professor has estimated.
The formula would apply if the powder
acted with equal force on the ball from its
commencement of motion until it left the
muzzle; but this is not the fact. The pow
der, or rather the expanding gases pro-
duced by its combustion, acts with most force
at the beginning Of the motion, and gradu-
ally dies away. We will present some
facts relating to the varying pressure on
the interior of a gun in our next issue.
Influence Of Holy Lits.-There is an
energy of moral suasion in good mans
life, passing the highest effort Of the orators