rom the cervical plexus.

I. Subscapular artery.

K. Tendon of latissimus dorsi muscle.

L. Teres major muscle.

[Illustration: Arm and chest, showing blood vessels, muscles and other
internal organs.]
Plate 13

PLATE 14.

A. Axillary vein.

B. Axillary artery.

C. Coraco-brachialis muscle.

D. Short head of the biceps muscle.

E. Pectoralis major muscle.

F. Mammary gland, seen in section.

G. Serratus magnus muscle.

H. Lymphatic gland; h h, other glands of the lymphatic class.

I. Subscapular artery, crossed by the intercosto-humeral nerves and
descending parallel to the external respiratory nerve. Beneath the
artery is seen a subscapular branch of the brachial plexus, given
to the latissimus dorsi muscle.

K. Locality of the subclavian artery.

L. Locality of the brachial artery at the bend of the elbow.

[Illustration: Arm and chest, showing blood vessels, muscles and other
internal organs.]
Plate 14

COMMENTARY ON PLATES 15 & 16.

THE SURGICAL DISSECTION OF THE BEND OF THE ELBOW
AND THE FOREARM, SHOWING THE RELATIVE POSITION
OF THE ARTERIES, VEINS, NERVES, &c.

The farther the surgical region happens to be removed from the centre of
the body, the less likely is it that all accidents or operations which
involve such regions will concern the life immediately. The limbs
undergo all kinds of mutilation, both by accident and intention, and yet
the patient survives; but when the like happens at any region of the
trunk of the body, the life will be directly and seriously threatened.
It seems, therefore, that in the same degree as the living principle
diverges from the body's centre into the outstanding members, in that
degree is the life weakened in intensity; and just as, according to
physical laws, the ray of light becomes less and less intense by the
square of the distance from the central source, so the vital ray, or
vis, loses momentum in the same ratio as it diverges from the common
central line to the periphery.

The relative anatomy of every surgical region becomes a study of more or
less interest to the surgeon, according to the degree of importance
attaching to the organs contained, or according to the frequency of such
accidents as are liable to occur in each. The bend of the elbow is a
region of anatomical importance, owing to the fact of its giving passage
to C, Plate 15, the main artery of the limb, and also because in it are
located the veins D, B, E, F, w