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accumulation of pictures and records which we would gladly eliminate from the stock material of dreams; but much may be done to improve the store as a whole by feeding the mind with wholesome and healthy thoughts and impressions. He who makes it a rule through life—beginning early in youth—to take care that what he puts away in his mind and accumulates is, as far as may be possible, a treasure of pure and good materials, will do much toward making the dreams that haunt his sleep in the later years of life not only tolerable, but, so far as night-thoughts can subserve any useful or beneficial purpose, improving. There can be no question that pleasant dreams sometimes afford relief to the mind, especially when they occur on awaking, or when they blot out the disagreeable impressions of the day, and facilitate the process of passing into a state of natural and complete sleep. Such dreams do not last long, and are seldom so intense as to distress the faculties. There is always a danger, in light sleep, of the senses being partially awake to surrounding impressions, and making them the pegs on which to hang a dream. It is, therefore, important to secure the most peaceful and negative conditions for sleep. Dreams are often made by the externals of the sleeper. To avoid this contingency, the sleeper should train his senses to disregard the external when composing himself for sleep. This is not difficult to do if the mind is set resolutely for a few nights in succession to shut out or ignore the impressions that strive to attract it through either or all of the senses. It is happily not required of us to know the way in which we accomplish all the acts we perform; and, in respect to some, it is better not to be too curious concerning the means if we gain the end. In regard to dreams and the making of dreams it will, however, be found an advantage to be fairly well-informed.—Gentleman's Magazine.
By Dr. MAX VON PETTENKOFER.
WATER plays quite as important a part in the soil as air. Obviously, no organic* life, no organic change, can be conceived of without water; and we ourselves consist three parts in four of water. Therefore it may be inferred that change in the moisture of the soil must have a certain influence on its organic and organized constituents, and on the organic life within it. Two degrees of moisture in the soil may be especially distinguished: one in which air and water both
- An address delivered before the Association of German Naturalists and Physicians, at Salzburg, September 18, 1881.