Page:Popular Science Monthly Volume 25.djvu/636

620 are located in the frontal region. It is therefore a mistake to speak of memory as a single faculty of the mind. It is really an assemblage of distinct memories which we possess, each kind of memory being as different from the others both in its nature and in its location as are the different organs of sense through which the original perception came. These various memories are associated with each other, and this association is secured by means of fibers passing between and joining these different areas. It is also a mistake to give memory as a whole a location in one place as the phrenologists do. Our various memories are scattered over the brain in different regions, being distributed at the time of the perception of the sensation remembered in accordance with the anatomical connection of the percipient organ. It is, finally, a mistake to speak of a good memory or a bad memory. The degree of power to remember differs in our various kinds of memory. One man can remember things seen; another can remember things heard; a third is skillful in the performance of certain motions, and may be said to possess a good motor-memory. A fourth acquires languages readily. So each of us has a stronger and a weaker kind of memory, and it is important to recognize this, in order to train and educate the weaker memory up to the level of the stronger one. The memories which we possess are our actual memories. But around these are areas of gray matter still unoccupied by memory-pictures, and in these potential areas new memories can be stored up. The actual area is always extending, the potential area is diminishing, as we acquire new facts. The wider and more varied our knowledge, the greater the actual area of any one memory, and the more complete our command over our inherent brain-power.



HE geographical ideas of the lower races, as well as those of civilized people, are of both ethnological and psychological interest, and it is my purpose to devote a few lines to the little-worked field which here presents itself to view. The special subject of my essay will be the ideas concerning the earth and the world formed by primitive peoples, especially the ideas of the form of our planet and of the most important sidereal phenomena; and among primitive peoples I shall, for the purpose of this review, include such half-civilized nations as the Toltecs and Aztecs, and the ancient Peruvians.

Men form different notions of the sky and the earth according to their different points of view. The first appearance of the earth is that of an unbounded surface, and the constructive mind forms a 