CAN 
from the nuizzlc to the object, but forms a 
curve often many yards above the horizontal 
line. The point blank distance is according 
to the calibre of the piece, and the propor- 
tion of powder, and its quality, used for a 
charge ; we may, however, state the ranges 
to be from 400 to 1000 yards. 
Mortars will throw shells more than a 
mile. The carriage of a mortar is a large 
horizontal bed of timber, strongly clamped 
together, and placed on loose sand ; it should 
be perfectly level. The breech of a mortar 
is round, and rests in a hollow made in the 
centre of the bed ; its muzzle is held up by 
a curved iron stay, which being acted upon 
by a screw gives the mortar more or less 
elevation : the trunnions are close to the 
breech, and move upon the bed. 
We shall conclude this article with a 
short description of the method of cannon 
boring. 
Fig. 1. Plate Cannon, &c. is an elevation 
of a machine for boring cannon ; and fig. 2. 
is a plan of it ; the same references are used 
in both figures : A is a cast iron frame to sup- 
port the bearing for an iron shaft, B, turn- 
ed by a steam engine or water wheel, this 
has a square box on its end, into which a 
square knob cast on the end of the gun is 
fitted by screws ; the mouth of the gun is 
supported on an iron frame, 1.1, sliding on 
the two bed beams, E, E, and can be fixed 
at any place by screws ; it has also screws to 
elevate or depress the brass which forms 
the bearing for the gun; F is the boring 
bar fastened at its end to a large block, G, 
running on the bed beams with small 
wheels : H is a rack fastened by its ends to 
puppets wedged on the bed, passing through 
the block G : a pinion which works in this 
rack, is attached to the block G, and its 
spindle has a wheel, I, with pins projecting 
from it: K is a bar going between these 
pins, and carrying a weight which turns the 
pinion, and forces the block G, and the bor- 
ing bar towards the gun. When the weight 
reaches the ground it must be lifted up, and 
its lever, K, hooked between two fresh pins 
of the wheel. 
Cannon, with letter-founders and prin- 
ters, a large sized letter distinguished by 
this name. 
CANNONADE, in marine affairs, is the 
application of artillei^ to the purposes of 
naval war, or, the direction of its efforts 
against some distant objects intended to be 
seized or destroyed, as a sliip, battery, 
fortress, &c. 
CANNULA, in surgery, a tube made of 
CAN 
different metals, principally of silver and 
lead, but sometimes of iron. 
CAN OE, a small boat, made of the trunk 
of a tree, bored hollow ; and sometimes 
also of pieces of bark, served together. It 
is used by the natives of America to go a 
filling in the sea, or upon some other ex- 
pedition, either by sea, or upon the rivers 
and lakes. 
CANON, commonly called prebendary, 
a person who possesses a prebend, or reve- 
nue allotted for the performance of divine 
service in a cathedral or collegiate church. 
Originally, canons were only priests, or 
inferior ecclesiastics, who lived in com- 
munity, residing near the cathedral church 
to assist the bishop, depending entirely on 
his will, supported by the revenues of his 
bishopric, and living in the same house as his 
domestics or counsellors, 6ic. By degrees, 
these communities of priests, shaking off 
their dependance, formed separate bodies ; 
in time they freed themselves from their 
rules, and at length ceased to live in a 
community. It is maintained that the col- 
leges of canons, which have been intro- 
duced into each cathedral, were not in the 
ancient church, but are of modern appoint- 
ment. 
' Canon, in an ecclesiastical sense, a law, 
rule, or regulation of the policy and disci- 
pline of a church, made by councils either 
general, national, or provincial. 
Canon (^scripture, a catalogue or list of 
the inspired writings or such books of the 
bible as are called canonical ; because 
they are in the number of those books 
which are looked upon as sacred, in oppo- 
sition to those which are either not ac- 
knowledged as divine books, or are rejected 
as heretical and spurious, and are called 
apocryphal. This canon may be consider- 
ed as Jewish and Christian, with respect to 
tlie sacred writings acknowledged as such 
by the Jews, and those admitted by the 
Christians. 
Canon, in music, a short composition of 
two or more parts, in which one leads., and 
the other follows : or it is a line of any 
length, shewing, by its divisions, how mu- 
sical intervals are distinguished, according 
to the ratios, or proportions, that the sounds 
terminating the intervals, bear one to an- 
other, when considered according to their 
degree of being acute or grave. 
Canon, in arithmetic, algebra, &c. is a 
rule to solve all things of the same nature 
with the present inquiry ; thus, every last 
step of an equation in algebra is such a 
