Page:Popular Science Monthly Volume 1.djvu/298

286 nerve-centres. We should see that a piece of news, a disaster, an impending trouble or difficulty, causes a man to lay awake at night, and we should know that he lies awake because his brain circulation, either through the whole or in parts of his cerebral hemispheres, is higher than admits of sleep. There is an extrication of force going on in the shape of thought, there is a flow of blood going to the excited part. We cannot see all this, however, but we can and do see how emotion causes the face to flush and the pulse to quicken, how those who lie awake suffer from heat of head and suffusion of eyes, how emotion increases the lachrymal secretion, the lacteal, and others. And when we say that emotion does these things, we merely mean that something or other has stimulated the brain into producing these phenomena, and that along with the stimulus the feeling of grief or shame or anger coexists.

If all this be true, it may perchance throw some light upon many of the phenomena of disordered mind and brain: it may help us to understand why, with almost the same delusion, e.g., that the newspapers are writing about him, one man will be exultant, another angry, another depressed; it may explain why the same man is at one time maniacal, at another melancholic. Lack of force may account for the wretched feeling of the hypochondriac and the hysterical, for the mental pain which many feel when they are below par: and a proneness to part with force, to convert it into action, may be the condition of the centres of those who are excitable and impulsive, a condition analogous to that brought about in certain centres by such drugs as strychnia, by such diseases as epilepsy and convulsions, or evidenced by such an affection as stammering.—Fortnightly Review.



E propose to give a brief sketch of what is known respecting the noble planet Jupiter. He is the giant of the solar system, himself the primary of a scheme of orbs whose movements resemble in regularity the motions of the planets round the sun. Much has been discovered during the last few years—nay, even during the last few months—to render such a sketch interesting.

We must, in the first place, dispossess ourselves of the notion, not uncommonly entertained, that Jupiter is one of a family of orbs, nearly equal in dignity and importance, and comprising the Earth and Venus, Mars and Mercury, among its members. This idea still prevails, 