We will come now, if you please to sensibility, which belongs to the nerves.
A. I have a very indefinite idea of the nerves.
E. My ideal is sufficiently definite in its shape, but so droll! I do not think of them as "being flesh of my flesh," but as a species of the genus fairy. They are to us, what the Nereides are to the green wave, the Dryades to the oak, and the Hamadryades to the little flower. They are quite omnipotent in their operations. They make us cry or they make us laugh; thrill us with rapture or woe as they please. And, my dear Isabel, I shall not allow you to cheat me out of this pleasing fancy. You may tell us just what they are, but I shall be as incredulous as possible.
I. They are very slender white cords, extending from the brain and spinal marrow—twelve pairs from the former, and thirty from the latter. These send out branches so numerous that we cannot touch the point of a pin to a spot that has not its nerve. The mucous membrane is—
F. Oh, these technicals! What is the mucous membrane?
I. It is a texture, or web of fibres, which lines all cavities exposed to the atmosphere—for instance, the mouth, windpipe and stomach. It is the seat of the senses of taste and smell.
E. And the nerves are the little witches that inform the brain how one thing is sweet, another bitter; one fragrant, another nauseous. Alimentiveness ever after frowns or smiles accordingly. So it seems that the actions of the brain, and of the external senses, are reciprocated by the nerves, or something of this sort. How is it, Isabel? Oh, I see! You say sensibility belongs to the nerves. So sights by means of—of what?
I. Of the optical nerves.
E. Yes; and sounds by means of the—
I. Auditory nerves.