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 the brain and spinal cord. They are related in the following extract, which has been translated from the account given by Neuburger (op. cit., Vol. I., p. 380):—

The brain itself is not sensitive; it expands and contracts synchronously with the respiratory movements, the purpose of which action is to drive the pneuma from the cavities of that organ into the nerves. The function of the meninges is to hold the parts firmly together and to unite the blood-vessels. Pressure upon the brain causes stupor. An injury of the tissues surrounding the fourth ventricle or of those which constitute the beginning of the spinal cord produces death. The seat of the soul is in the substance of the brain, and not in its membranes. The spinal cord serves as a conductor of sensation and of motor impulses, and it also plays the part of a brain for those structures of the body which lie below the head. It gives off nerves like streamlets. Division of the spinal cord longitudinally in its median axis does not give rise to paralysis. Transverse division, on the other hand, causes symmetrical paralyses. If the cord is divided between the third and fourth cervical vertebrae, respiration is arrested, and if the division is made between the cervical and the thoracic portions of the spinal column, the animal breathes with the aid only of its diaphragm and of the upper muscles of the trunk of the body. Division of the recurrent nerves produces aphonia; if the fifth cervical nerve is divided, the scapular muscles on the corresponding side will be paralyzed. Galen considers the ganglia to be organs for reinforcing the energy of the nerves. The fact that both cerebral and spinal-cord nerve-filaments enter into the composition of the sympathetic nerve explains the extraordinary sensitiveness of the abdominal organs.

When we consider that these experiments are the first of their kind of which history makes mention, that they were carried out nearly seventeen hundred years ago, and that—so far as we know—they sprang entirely from the brain of the experimenter, we may well express unlimited admiration for Claudius Galen.

Daniel Le Clerc says that Galen's principal treatise on human physiology, entitled "Utility of the Different Parts of the Human Body," constitutes a chef-d'oeuvre which has challenged the admiration of physicians and philosophers in all ages. Christians, however, he adds, are