The daily Gate City and constitution-Democrat. (Keokuk, Iowa) 1916-1922, 1920-11-15


March g, 1918, had been identifies
as artillery fire, the verdict was
unanimous that the Germans had IN
vented a marvellous new super-an
mon Not until recently. when the
Germans permitted American army
officers Of the ordnance corps to visit
some Of their huge armories, was il
known that those cannon, fer al;
their seventy fre-mile range, we're no!
inventions. Neither were they new.
To cap the anti-climax even further,
il was discovered the supercannou
was just pieces of old, worn-out guns,
put together.
4 II was actually just neat BIT OF
patchwork that startled the world.
To begin on the Big Berthas. as the
French like to call them, the Germans
took a WORKOUT fifteeniRch naval
gun. which is quite a piece Of ord
nance itself. That was the basis OF
the work as described by Lieut. Col
81. W. Miller in Mechanical Engineer
Ing
Rebored An Old Cur.
/ The length Of that section was III
meters, or ffty-six feet 1t was bored
out and q very heavy tube with an
meters (s.3 inches) was inserted, with
about forty feet OF it projecting be
yond the end OF the original gun.
Over that another hoop was shrunk
ard locked to the forward hoop. There
also was patch of six meters (l9.a
feet). which was attached as the
muzzle Of the gun by interrupted
threads and flanges.
: - - -or
uniform rifiing. the lands and
grooves which inpart q rotary motion
to the projectile The six-meter sec
ever, was unrified, probably designed
to steady the projectile and defeat
its slight tendency 10 rumble" or
raw and fail TO travel directly TO its
mark. Such ..tumbling is caused by
the conflict of two forces. one spin
ming the Droiectile to the right. the
other sending it forward. 1t VIII be
understood that such force had TO
be obTiated. when it is considered
that the shell had to travel upward
twenty-four miles on its arc in order
to cover the horizontal distance OF
seventy-five miles.
Such was the giant gun itself, 49,
600 pounds IN weight, 122 feet long.
The life of every piece of artillery
necessarily is very limited and that
Of this monster, under the heavy
pressure OF its high velocity proiec-
tile, necessarily rrore limited than
others. But vhen the Germans found
the span OF the gin amounted to only
fifty rounds, they hit upon clever
eIpedient- They bored out the FL
centimeter tube, which was very
thick, to "a en-. and later to 26 en-,
giving ii Just 80 much more life at
each caliber with only a change TO
larger ammunition required. After
that, however, new gun was neces-
say
Fired at the Stars.
An important factor IN the great
range the gun was able to attain was
the unusually high elevation at which
it was fired While II had been be-
lieved that nothing was to be gained
in range by elevating gum above As
degrees, Big Bertha was hred at 55.
At so great an elevation, the German
imagined they were opening FIRE on
the stars Ia a war between worlds.
Probably other factors in the range
projectile with its ogive cap. separate
charges and careful machining, and
the heavy charge of powder. designed
to give a maximum muZzle velocity
withou excessive pressure.
Among the novel features Of the
monster which catapulted steel out of
the forest of St Gobain into the heart
OF Paris, seventy miles away, was
~ xrysS &c hyvFN MI n
recofl mechanism which restrained
the hinge cannon to kick Of only
sos inches, only little longer than
a s-inch gun requires. A spring pneu-
matte cylinder put the gun back into
battery.
The elevating mechanism OF the
gun was 2-speed affair. controlled by
two handles. At low speed, two men
could operate it, but for high speed,
eight men were required to point the
mon ster's muZzie skyward. Four men
operated the traversing mechanism.
Then there was also a rotating sec
ton on which the gun carriage was
mounted That section turned on a
base, thirty-five feet IN diameter. Thus
the supercannon could spring around
on Frs concrete base for fire in any
direction.
The ss,en hurled by the cannon
3s4 pounds and was nineteen
inches long. The projectfle's surface
was rfied 80 as to at into the rif1ins
Of the bore and thus impart the
necessary rotating motion. The cop
per bands which generally serve that
purpose on projectiles could not be
used their shearing strength being
to Withstand the extreme
at which the big guns
shells had to departs in order to travel
their long journey.
Gun Lacked Accuracy.
Al to the accuracy of the guns
fire. not much more can be said for
Il than that It hit the city of Paris.
Maps show the bursts scattered well
5ver IA area OF the city about nine
rlometers square. So great was the
IT was evident it woufd
have been useless to lay on much
smaller target II was noted from