Cannon Tools & Implements
Gunner's equipment was numerous. There were the tompion
(a lid that fitted over the muzzle of the gun to keep wind and weather
out of the bore) and the lead cover for the vent; water buckets for the
sponges and passing boxes for the powder; scrapers and tools for
"searching" the bore to find dangerous cracks or holes; chocks for the
wheels; blocks and rollers, lifting jacks, and gins for moving guns; and
drills and augers for clearing the vent (figs. 17, 44). But among the
most important tools for every day firing were the following:
FIGURE 44—EIGHTEENTH CENTURY GUNNER'S EQUIPMENT. (Not to scale.)
The sponge was a wooden cylinder about a foot
long, the same diameter as the shot, and covered with lambskin. Like all
bore tools, it was mounted on a long staff; after being dampened with
water, it was used for cleaning the bore of the piece after firing.
Essentially, sponging made sure there were no sparks in the bore when
the new charge was put in. Often the sponge was on the opposite end of
the rammer, and sometimes, instead of being lambskin-covered, the sponge
was a bristle brush.
The wormer was a double screw, something like
a pair of intertwined corkscrews, fixed to a long handle. Inserted in
the gun bore and twisted, it seized and drew out wads or the remains of
cartridge bags stuck in the gun after firing. Worm screws were sometimes
mounted in the head of the sponge, so that the piece could be sponged
and wormed at the same time.
The ladle was the most important of all the
gunner's tools in the early years, since it was not only the measure for
the powder but the only way to dump the powder in the bore at the proper
place. It was generally made of copper, the same gauge as the windage of
the gun; that is, the copper was just thick enough to fit between ball
Essentially, the ladle is merely a scoop, a metal
cylinder secured to a wooden disk on a long staff. But before the
introduction of the powder cartridge, cutting a ladle to the right size
was one of the most important accomplishments a gunner had to learn.
Collado, that Spanish mathematician of the sixteenth century, used the
culverin ladle as the master pattern (fig. 45). It was 4-1/2 calibers
long and would carry exactly the weight of the ball in powder. Ladles
for lesser guns could be proportioned (that is, shortened) from the
The ladle full of powder was pushed home in the bore.
Turning the handle dumped the charge, which then had to be packed with
the rammer. As powder charges were lessened in later years, the ladle
was shortened; by 1750, it was only three shot diameters long. With
cartridges, the ladle was no longer needed for loading the gun, but it
was still handy for withdrawing the round.
FIGURE 45—SIXTEENTH CENTURY PATTERN FOR GUNNER'S LADLE.
The rammer was a wooden cylinder about the
same diameter and length as the shot. It pushed home the powder charge,
the wad, and the shot. As a precaution against faulty or double loading,
marks on the rammer handle showed the loaders when the different parts
of the charge were properly seated.
The gunner's pick or priming wire was a sharp
pointed tool resembling a common ice pick blade. It was used to clear
the vent of the gun and to pierce the powder bag so that flame from the
primer could ignite the charge.
Handspikes were big pinch bars to manhandle
cannon. They were used to move the carriage and to lift the breech of
the gun so that the elevating quoin or screw might be adjusted. They
were of different types (figs. 33a, 44), but were essentially
6-foot-long wooden poles, shod with iron. Some of them, like the
Marsilly handspike (fig. 11), had rollers at the toe so that the
wheelless rear of the carriage could be lifted with the handspike and
rolled with comparative ease.
The gunner's quadrant (fig. 46), invented by
Tartaglia about 1545, was an aiming device so basic that its principle
is still in use today. The instrument looked like a carpenter's square,
with a quarter-circle connecting the two arms. From the angle of the
square dangled a plumb bob. The gunner laid the long arm of the quadrant
in the bore of the gun, and the line of the bob against the graduated
quarter-circle showed the gun's angle of elevation.
The addition of the quadrant to the art of artillery
opened a whole new field for the mathematicians, who set about compiling
long, complicated and jealously guarded tables for the gunner's
guidance. But the theory was simple: since a cannon at 45° elevation
would fire ten times farther than it would when the barrel was
level (at zero° elevation), the quadrant should be marked into ten
equal parts; the range of the gun would therefore increase by
one-tenth each time the gun was elevated to the next mark on the
quadrant. In other words, the gunner could get the range he wanted
simply by raising his piece to the proper mark on the instrument.
FIGURE 46—SEVENTEENTH CENTURY GUNNER'S QUADRANT. The long end of the
quadrant was laid in the bore of the cannon. The plumb bob indicated the
degree of elevation on the scale.
Collado explained how it worked in the 1590's. "We
experimented with a culverin that fired a 20-pound iron ball. At
point-blank the first shot ranged 200 paces. At 45-degree elevation it
shot ten times farther, or 2,000 paces. . . . If the point-blank range
is 200 paces, then elevating to the first position, or a tenth
part of the quadrant, will gain 180 paces more, and advancing another
point will gain so much again. It is the same with the other points up
to the elevation of 45 degrees; each one gains the same 180 paces."
Collado admitted that results were not always consistent with theory,
but it was many years before the physicists understood the effect of air
resistance on the trajectory of the projectile.
Sights on cannon were usually conspicuous by
their absence in the early days. A dispart sight (an instrument similar
to the modern infantry rifle sight), which compensated for the
difference in diameter between the breech and the muzzle, was used in
1610, but the average artilleryman still aimed by sighting over the
barrel. The Spanish gunner, however, performed an operation that put the
bore parallel to the gunner's line of sight, and called it "killing the
vivo" (matar el vivo). How vivo affected aiming is easily
seen: with its bore level, a 4-pounder falconet ranged 250 paces. But
when the top of the gun was level, the bore was slightly elevated
and the range almost doubled to 440 paces.
To "kill the vivo," you first had to find it.
The gunner stuck his pick into the vent down to the bottom of the bore
and marked the pick to show the depth. Next he took the pick to the
muzzle, stood it up in the bore, and marked the height of the muzzle.
The difference between the two marks, with an adjustment for the base
ring (which was higher than the vent), was the vivo. A little
wedge of the proper size, placed under the breech, would then eliminate
the troublesome vivo.
During the first half of the 1700's Spanish cannon of
the "new invention" were made with a notch at the top of the base ring
and a sighting button on the muzzle, and these features were also
adopted by the French. But they soon went out of use. There was some
argument, as late as the 1750's, about the desirability of casting the
muzzle the same size as the base ring, so that the sighting line over
the gun would always be parallel to the bore; but, since the gun usually
had to be aimed higher than the objective, gunners claimed that a fat
muzzle hid their target!
FIGURE 47—SEVENTEENTH CENTURY GUNNER'S LEVEL. This tool was useful in
many ways, but principally for finding the line of sight on the barrel
of the gun.
Common practice for sighting, as late as the 1850's,
was to find the center line at the top of the piece, mark it with chalk
or filed notches, and use it as a sighting line. To find this center
line, the gunner laid his level (fig. 47) first on the base ring, then
on the muzzle. When the instrument was level atop these rings, the plumb
bob was theoretically over the center line of the cannon. But guns were
crudely made, and such a line on the outside of the piece was not likely
to coincide exactly with the center line of the bore, so there was still
ample opportunity for the gunner to exercise his "art." Nonetheless the
marked lines did help, for the gunner learned by experiment how to
compensate for errors.
Fixed rear sights came into use early in the 1800's,
and tangent sights (graduated rear sights) were in use during the Civil
War. The trunnion sight, a graduated sight attached to the trunnion,
could be used when the muzzle had to be elevated so high that it blocked
the gunner's view of the target.
Naval gunnery officers would occasionally order all
their guns trained at the same angle and elevated to the same degree.
The gunner might not even see his target. While with the crude
traversing mechanism of the early 1800's the gunners may not have laid
their pieces too accurately, at least it was a step toward the indirect
firing technique of later years which was to take full advantage of the
longer ranges possible with modern cannon. Use of tangent and trunnion
sights brought gunnery further into the realm of mathematical science;
the telescopic sight came about the middle of the nineteenth century;
gunners were developing into technicians whose job was merely to load
the piece and set the instruments as instructed by officers in fire
control posts some distance away from the gun.
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