CANNON. 
nbn is firmly fixed on a frame, and the borer 
approaches as tlie chace proceeds. There 
is a lai'ge cylindrical projection on each side 
of a cannon, nearly in the middle of its 
lenatii ; tii ^se are called trunnions, they 
serve to support it on the carriage, and as 
pivots, whereon a due degree of elevation or 
' depression may be given. This variation 
in the elevation is made in field-pieces which 
usually carry balls of.3, 6, 9, 12, and up to 
18lb. weight, by means of a screw fixed to 
a strong piece of wood that joins the two 
cheeks of the carriage, and is fastened by a 
loop and bolt to the round knob at the end 
of the cannon, called the cascabel. As 
there is great force in the powder when 
ignited by means of a match applied to the 
vent, which communicates with the end of 
the chace, the quantity of metal must, of 
necessity, be augmented about the breech, 
or hinder parts. Thus all cannons are for- 
tified in that part ; but battering cannons 
are generaliy double-fortified, by an addi- 
tional quantity of metal, in consequence of 
the lai'ge charges of powder given for the 
purpose of adding to the impetus or force of 
the sljot’s action on the [dace to be battered. 
Battering-pieces are generally from 24 to 
42 pounders, sometimes 18 pounders are 
used, but their effect is feeble compared 
with that of cannons of a larger calibre. 
C'dnnon intended for field service are 
mounted on a carriage, with two stout 
wheels about four feet and a half high, on a 
solid wooden, or an iron axle, and suspend- 
ed by their trunnions on the two cheeks, 
which are as near to each other as the size 
of the cannon will permit, tapering down a 
Kttle towards the ground at a sufficient 
angle to oppose the recoil, or run back- 
ward, made by every piece when fired. 
The cheeks diverge a little, and are kept 
very firm in tlieir places by means of cross 
pieces called transoms, which are vertical 
in and secured by strong bolts. The can- 
non is turned about to any direction by 
means of a hand-spike which fixes into the 
train. The piece is transported by raising 
its train, and passing the tail-transom, which 
is perforated for the purpose, on to a very 
substantial iron gudgeon firmly fixed on the 
centre of an axle, which has two wheels 
rather lower than those of the carriage. 
This appendage is called a limber, and car- 
ries a stout water-proof box full of ammuni- 
tion of various descriptions, for the service 
of the cannon; it has hkewise a pole, or 
shafts, whereby horses are attached, and 
♦lie piece thus travels with tolerable ease j 
the limber wheels traversing under the 
cheeks of the carriage. 
Tile modes of charging cannon are va- 
rious, but in general with cartridges, over 
which wads of spun yarn are well rammed ; 
then the shot, either round or grape ; and, 
l-astly, a second wad rammed home : but in 
field service, where grape or cannister shot 
are used, the whole charge is sometimes 
made to fit in immediately after the cart- 
ridge, which is invariably made of surge, 
shalloon, or other woollen stuff". Grape is 
made by putting many small balls together 
so as to fit the bore of-the piece ; they are 
usually netted to a round piece of hoard. 
Cannister is nothing more than a number oF 
still smaller balls put into a tin cannister ; 
these are intended for close attacks, espe- 
cially among cavalry, or lai'g© bodies of 
infantry : round shot being more suited to 
distant operations. Ship guns, and such 
others as are intended to be stationary, are 
placed on low substantial carriages, moving 
on four small trucks ; these are elevated by 
means of wedges called quoins. Some are 
discharged by locks, on the same principles 
as those for musquets ; and for ship use are 
certainly the safest, and best adapted to a 
certainty of aim. Brass six-pounders often 
weigh so little as 4cwt. but some of the 
double fortified battering cannon amount to 
full 3 tons each, 
A siiort kind of cannon called a carronade 
is much in naval use : we have some that 
throw balls of near TOlbs : their purpose is 
ciiiefly for close attacks, when their effects 
are dreadful : these slide in grooves on a 
bed Carriage. Tiie pieces used for throwing 
shells, which are hollow balls filled with 
powder that explode when the fuse burns 
into them, are howitzers and mortars ; the 
former are mounted in every respect similar 
to cannon, but are very short and chamber- 
ed. Tliese throw either shells or grape 
with great effect. The mortar is always 
fired at an elevation of 45 degi'ees from the 
horizon, and its range, i. e. the distance at 
which the shell is to fall, is determined by 
putting a greater or less charge of powder 
into the chamber. Shells for mortars some- 
times measure a diameter of 21 inches, but 
those for howitzers I'arely exceed 11 inches, 
and generally are from 4;i to 8i, or there- 
abouts. The point blank range of a cannon 
is that distance at which the shot cuts a 
line, supposed to be drawn parallel with 
the surface of earth, at a distance equal to 
the height of the chace of the cannon when 
horizontal. No shot goes in a right line 
