ANATOMY. 
body, is strengthened at its sides by two 
bony processes, called the internal and ex- 
ternal malleoli or ankles. 
The bones of the tarsus, metatarsus, and 
toes, are articulated like those of the hand. 
MYOLOGY. 
Muscles consist of bundles of red fibres; 
but the colour is not essential, since it can 
be removed by repeated washings and ma- 
ceration. 
The threads composing a muscle are en- 
veloped by cellular substance, which con- 
nects it to the surrounding parts. Each 
bundle consists of numerous fibres, so small 
that our instruments of research cannot ar- 
rive at the ultimate or original fibre : hence 
any perceivable fibre, however small, is 
formed by the juxta-position of numerous 
fibrillae ; and, as we employ magnifying in- 
struments of greater power, a fibre, which 
before seemed simple, resolves itself into a 
congeries of still more minute threads. We 
pass over in silence the dreams of various 
investigators who have busied themselves in 
looking for the ultimate muscular fibre ; 
these researches do not assist us in explain- 
ing the phenomena of muscular action. The 
cohesion of the constituent particles of the 
moving fibre is maintained by the vital 
power: hence a dead muscle will be torn 
by a weight of a few ounces, which in the 
liviqg body would have supported many 
pounds. The muscular fibre receives a 
copious supply of vessels and nerves. 
Tendons are formed by an assemblage of 
longitudinal parallel fibres. They are ex- 
tremely dense and tough, of a splendid 
white colour, which is beautifully contrasted 
with the florid red of a healthy muscle. The 
muscular fibres terminate in these bodies, 
and they are connected to the bones. They 
possess no apparent nerves, and very few 
and small blood-vessels. 
There is always an exact relation between 
the joint and the muscles that move it. 
Whatever motion the joint, by its mechani- 
cal construction, is capable of performing, 
that motion the annexed muscles by their 
position are capable of producing. For ex- 
ample, if there he, as at the knee and elbow, 
a hinge joint, capable of motion only in the 
same plane, the muscles and tendons are 
placed in directions parallel to the bone, so 
as by their construction to produce that 
motion and no other. If these joints were 
capable of a freer motion, there are no 
muscles to produce it. Whereas, at the 
shoulder and the hip, where the hall and 
socket joint allows by its construction a ro- 
tatory or sweeping motion, tendons are 
placed in such a position, and puli in such a 
direction, as to produce the motion of which 
the joint admits. In the head and hand 
there is a specific mechanism in the hones 
for rotatory motion ; and there is accord- 
ingly in the oblique direction of the muscles 
belonging to them a specific provision for 
putting this mechanism of the bones into ac- 
tion. Tlie oblique muscles would have been 
inefficient without that particular articula- 
tion, and that particular articulation would 
have been useless without the muscles. 
As the muscles act only by contraction, it 
is evident that the reciprocal energetic mo- 
1 ion of the limbs, or their motion with force 
in opposite directions, can only be produced 
by the instrumentality of opposite or anta- 
gonist muscles, of flexors and extensors an- 
swering to each other. For instance, the 
biceps and brachialis internus, placed in the 
front of the arm, by their contraction bend 
tne elbow, and with such degree of force as 
the case requires, or the strength admits of. 
Ihe relaxation of these muscles after the ef- 
fort would merely let the fore-arm drop 
down : for the back stroke therefore, and 
that the arm may not only bend at the el- 
bow, hut also extend and straighten itself 
with force, other muscles, as the triceps and 
anconeus, placed on the hinder part of the 
arm, fetch back the fore-arm into a straight 
line witii the humerus with no less force than 
that with which it was bent out of it. It 
is evident therefore that the animal func- 
tions require that particular disposition of 
the muscles, which we call antagonist mus- 
cles. 
It often happens that the action of mus- 
cles is wanted, where their situation would 
be inconvenient. In which case, the body 
of the muscle is placed in some commodious 
position at a distance, and it communicates 
with- the point of action by slender tendons. 
If the muscles, which move the fingers, had 
been placed in the palm or back of the hand, 
they would have swelled that part to an 
awkward and clumsy thickness. The beau- 
ty, the proportions of the part wonld have 
been destroyed. They are therefore dis- 
posed in the arm, and even up to the elbow, 
and act by long tendons strapped down at 
the wrist, and passing under the ligament 
to the fingers, and to the joints of the fin- 
gers, which they are severally to move. In 
tire same manner the muscles which move 
the toes and many of the joints of the foot, 
are gracefully disposed in the calf of th<J 
IMP 
