7. The facial, or seventh pair of nerves, are distributed over the face, and give it expression. [Footnote: If it is palsied, on one side there will be a blank, while the other side will laugh or cry, and the whole face will look funny indeed. There were some cruel people in the middle ages who used to cut the nerve and deform children's faces in this way, for the purpose of making money of them at shows. When this nerve was wrongly supposed to be the seat of neuralgia, or tic douloureux, it was often cut by surgeons. The patient suffered many dangers, and no relief of pain was gained.—MAPOTHER.]
FIG. 55.
[Illustration: The Brain and the origin of the twelve pairs of Cranial Nerves. F, E, the cerebrum; D, the cerebellum, showing the arbor vitæ; G, the eye; H, the medulla oblongata; A, the spinal cord; C and B, the first two pairs of spinal nerves.]
8. The auditory, or eighth pair of nerves, go to the ears, and are the nerves of hearing.
9. The glos-so-pha-ryn'-ge-al, or ninth pair of nerves, are distributed over the mucous membrane of the pharynx, tonsils, etc.
10. The pneu-mo-gas'-tric, or tenth pair of nerves, preside over the larynx, lungs, liver, stomach, and one branch extends to the heart. This is the only nerve which goes so far from the head.
11. The accessory, or eleventh pair of nerves, rise from the spinal cord, run up to the medulla oblongata, and thence leave the skull at the same opening with the ninth and tenth pairs. They regulate the vocal movements of the larynx.
12. The hyp-o-glos'-sal, or twelfth pair of nerves, give motion to the tongue.
FIG. 56.
[Illustration: Spinal Nerve, Sympathetic Cord, and the Network of Sympathetic Nerves around the Internal Organs. K, aorta; A, ophagus; B, diaphragm; C, stomach.]