Oxford.

The directions he gives for dissection show that he was a master of the
art. In dissecting out the portal vein and its ramifications, for
instance, he advises that a probe should be inserted into the vein, and
the point of the probe gradually advanced as the surrounding tissue is
cut away, so that finally the minute branches are exposed; and he
describes the use of the blowpipe, and other instruments used in
dissection. He carried out the experiment of tying the iliac and
axillary arteries in animals, and found that this procedure stopped the
pulse in the leg and arm, but caused no serious symptoms, and he found
that even the carotid arteries could be tied without causing death. He
also pointed out that tying the carotid artery did not cause loss of
voice, but that tying the artery carelessly so as to include the nerve
had this effect. He was the first to describe the ductus arteriosus, and
the three coats of the arteries.

It is highly improbable that Galen dissected human bodies in Rome,
though he dissected a great variety of the lower animals. He writes that
the doctors who attended Marcus Aurelius in the German wars dissected
the dead bodies of the barbarians. The chief mistakes made by Galen as
an anatomist were due to his assumption that what is true of the anatomy
of a lower animal is true also when applied to man.

Galen greatly assisted the advance of physiology by recognizing that
every part of the body exists for the purpose of performing a definite
function. Aristotle, like Plato, had taught that "Nature makes nothing
in vain," and Galen's philosophy was greatly influenced by the teaching
of Aristotle. Galen regarded his work as "a religious hymn in honour of
the Creator, who has given proof of His Omnipotence in creating
everything perfectly conformable to its destination."

He regarded the structure of various parts, such as the hand and the
membranes of the brain, as absolute perfection, although his idea of the
human hand was derived from a study of the ape's, and he had no
knowledge of the arachnoid membrane of the brain, but it would be unfair
to criticize his conclusions because of his failure to recognize a few
comparatively unimportant details. He discovered the function of the
motor nerves by cutting them experimentally, and so producing paralysis
of the muscles; the platysma, interossei, and popliteus muscles were
first described by him. He was the greatest authority on the pulse, and