50. Does liquor strengthen the muscles of a working man?
51. Is liquor a wholesome "tonic"?
52. Is it a good plan to take a glass of liquor before dinner?
VII.
THE NERVOUS SYSTEM.
"Mark then the cloven sphere that holds
All thoughts in its mysterious folds,
That feels sensation's faintest thrill,
And flashes forth the sovereign will;
Think on the stormy world that dwells
Lock'd in its dim and clustering cells;
The lightning gleams of power it sheds
Along its hollow, glassy threads!"
"As a king sits high above his subjects upon his throne, and from it speaks behests that all obey, so from the throne of the brain cells is all the kingdom of a man directed, controlled, and influenced. For this occupant, the eyes watch, the ears hear, the tongue tastes, the nostrils smell, the skin feels. For it, language is exhausted of its treasures, and life of its experience; locomotion is accomplished, and quiet insured. When it wills, body and spirit are goaded like overdriven horses. When it allows, rest and sleep may come for recuperation. In short, the slightest penetration may not fail to perceive that all other parts obey this part, and are but ministers to its necessities."—Odd Hours of a Physician. ANALYSIS OF THE NERVOUS SYSTEM.
| 1. THE STRUCTURE | | _ | 1. Description. | | 1. The Brain……..| 2. The Cerebrum. | | |_3. The Cerebellum. | | _ | | 2. The Spinal Cord..| 1. Its Composition. | | |_2. Medulla Oblongata. | | _ | 2. ORGANS OF | | 1. Description. | THE NERV- | | 2. Motory and Sensory. | OUS SYSTEM..| | 3. Transfer of Pain. | | | 4. The Spinal Nerves— | | | 31 Pairs. | |_3. The Nerves…….| 5. The Cranial Nerves— | | 12 Pairs. | | 6. Sympathetic System. | | 7. Crossing of Cords. | | 8. Reflex Action. | | 9. Uses of Reflex | | Action_ | _ | | 1. Brain Exercise. | | 2. Connection between Brain Growth and Body Growth. | 3. HYGIENE…..| 3. Sleep. | | 4. Effect of Sleeping Draughts. | |5. Sunlight. | | 4. WONDERS OF THE BRAIN. | | | 1. Alcohol (Con'd.) | | _ | 1. Stage of Excitement. | || | 2. Stage of Muscular | || | Weakness. | || 1. Effect of Alco- | 3. Stage of Mental | || hol upon the | Weakness. | || Nervous System | 4. Stage of Unconscious- | || | ness._ | || | || 2. Effect upon the Brain | ||3. Effect upon the Mental and Moral Powers. | | | | 2. Tobacco. | | | || 1. Constituents of Tobacco. | 5. ALCOHOLIC || 2. Physiological Effects. | DRINKS AND|| 3. Possible Disturbances produced by Smoking. |_ NARCOTICS.|| 4. Influence upon the Nervous System. || 5. Is Tobacco a Food? ||6. Influence of Tobacco on Youth. | | | 1. Description. | 3. Opium…………| 2. Physiological | | Effects._ | 4. Chloral Hydrate. | 5. Chloroform. |_6. Cocaine.
THE NERVOUS SYSTEM. [Footnote: The organs of circulation, respiration, and digestion, of which we have already spoken, are often called the vegetative functions, because they belong also to the vegetable kingdom. Plants have a circulation of sap through their cells corresponding to that of the blood through the capillaries. They breathe the air through their leaves, which act the part of lungs, and they take in food which they change into their own structure by a process which answers to that of digestion. The plant, however, is a mere collection of parts incapable of any combined action. On the other hand, the animal has a nervous system which binds all the organs together.]
STRUCTURE.—The nervous system includes the brain, the spinal cord, and the nerves. It is composed of two kinds of matter— the white, and the gray. The former consists of minute, milk-white, glistening fibers, sometimes as small as 1/25000 of an inch in diameter; the latter is made up of small, ashen-colored cells, forming a pulp-like substance of the consistency of blancmange. [Footnote: In addition to the cells, the gray substance contains also nerve fibers continuous with the white fibers, but generally much smaller. These form half the bulk of the gray substance of the spinal cord, and a large part of the deeper layer of the gray matter in the brain.—LEIDY'S Anatomy, p. 507.] This is often gathered in little masses, termed ganglions (ganglion, a knot), because, when a nerve passes through a group of the cells, they give it the appearance of a knot. The nerve fibers are conductors, while the gray cells are generators, of nervous force. [Footnote: What this force is we do not know. In some respects it is like electricity, but, in others, it differs materially. Its velocity is about thirty three meters per second.—Popular Physics, p. 244, Note.] The ganglia, or nervous centers, answer to the stations along a telegraphic line, where messages are received and transmitted, and the fibers correspond to the wires that communicate between different parts.