One of the first things to do, after arousing an interest, is to carefully note the landmarks and relative positions of the streets or roads over which you travel. So many people travel along a new street or road in an absent-minded manner, taking no notice of the lay of the land as they proceed. This is fatal to place-memory. You must take notice of the thoroughfares and the things along the way. Pause at the cross roads, or the street-corners and note the landmarks, and the general directions and relative positions, until they are firmly imprinted on your mind. Begin to see how many things you can remember regarding even a little exercise walk. And when you have returned home, go over the trip in your mind, and see how much of the direction and how many of the landmarks you are able to remember. Take out your pencil, and endeavor to make a map of your route, giving the general directions, and noting the street names, and principal objects of interest. Fix the idea of "North" in your mind when starting, and keep your bearings by it during your whole trip, and in your map making. You will be surprised how much interest you will soon develop in this map-making. It will get to be quite a game, and you will experience pleasure in your increasing proficiency in it. When you go out for a walk, go in a round-about way, taking as many turns and twists as possible, in order to exercise your faculty of locality and direction—but always note carefully direction and general course, so that you may reproduce it correctly on your map when you return. If you have a city map, compare it with your own little map, and also re-trace your route, in imagination, on the map. With a city map, or road-map, you may get lots of amusement by re-traveling the route of your little journeys.
Always note the names of the various streets over which you travel, as well as those which you cross during your walk. Note them down upon your map, and you will find that you will develop a rapidly improving memory in this direction—because you have awakened interest and bestowed attention. Take a pride in your map making. If you have a companion, endeavor to beat each other at this game—both traveling over the same route together, and then seeing which one can remember the greatest number of details of the journey.
Akin to this, and supplementary to it, is the plan of selecting a route to be traveled, on your city map, endeavoring to fix in your mind the general directions, names of streets, turns, return journey, etc., before you start. Begin by mapping out a short trip in this way, and then increase it every day. After mapping out a trip, lay aside your map and travel it in person. If you like, take along the map and puzzle out variations, from time to time. Get the map habit in every possible variation and form, but do not depend upon the map exclusively; but instead, endeavor to correlate the printed map with the mental map that you are building in your brain.
If you are about to take a journey to a strange place, study your maps carefully before you go, and exercise your memory in reproducing them with a pencil. Then as you travel along, compare places with your map, and you will find that you will take an entirely new interest in the trip—it will begin by meaning something to you. If about to visit a strange city, procure a map of it before starting, and begin by noting the cardinal points of the compass, study the map—the directions of the principal streets and the relative positions of the principal points of interest, buildings, etc. In this way you not only develop your memory of places, and render yourself proof against being lost, but you also provide a source of new and great interest in your visit.
The above suggestions are capable of the greatest expansion and variation on the part of anyone who practices them. The whole thing depends upon the "taking notice" and using the attention, and those things in turn depend upon the taking of interest in the subject. If anyone will "wake up and take interest" in the subject of locality and direction he may develop himself along the lines of place-memory to an almost incredible degree, in a comparatively short time at that. There is no other phase of memory that so quickly responds to use and exercise as this one. We have in mind a lady who was notoriously deficient in the memory of place, and was sure to lose herself a few blocks from her stopping place, wherever she might be. She seemed absolutely devoid of the sense of direction or locality and often lost herself in the hotel corridors, notwithstanding the fact that she traveled all over the world, with her husband, for years. The trouble undoubtedly arose from the fact that she depended altogether upon her husband as a pilot, the couple being inseparable. Well, the husband died, and the lady lost her pilot. Instead of giving up in despair, she began to rise to the occasion—having no pilot, she had to pilot herself. And she was forced to "wake up and take notice." She was compelled to travel for a couple of years, in order to close up certain business matters of her husband's—for she was a good business woman in spite of her lack of development along this one line—and in order to get around safely, she was forced to take an interest in where she was going. Before the two years' travels were over, she was as good a traveler as her husband had ever been, and was frequently called upon as a guide by others in whose company she chanced to be. She explained it by saying "Why, I don't know just how I did it—I just had to, that's all—I just did it." Another example of a woman's "because," you see. What this good lady "just did," was accomplished by an instinctive following of the plan which we have suggested to you. She "just had to" use maps and to "take notice." That is the whole story.
So true are the principles underlying this method of developing the place-memory, that one deficient in it, providing he will arouse intense interest and will stick to it, may develop the faculty to such an extent that he may almost rival the cat which "always came back," or the dog which "you couldn't lose." The Indians, Arabs, Gypsies and other people of the plain, forest, desert, and mountains, have this faculty so highly developed that it seems almost like an extra sense. It is all this matter of "taking notice" sharpened by continuous need, use and exercise, to a high degree. The mind will respond to the need if the person like the lady, "just has to." The laws of Attention and Association will work wonders when actively called into play by Interest or need, followed by exercise and use. There is no magic in the process—just "want to" and "keep at it," that's all. Do you want to hard enough—have you the determination to keep at it?
CHAPTER XIV.
HOW TO REMEMBER NUMBERS.
The faculty of Number—that is the faculty of knowing, recognizing and remembering figures in the abstract and in their relation to each other, differs very materially among different individuals. To some, figures and numbers are apprehended and remembered with ease, while to others they possess no interest, attraction or affinity, and consequently are not apt to be remembered. It is generally admitted by the best authorities that the memorizing of dates, figures, numbers, etc., is the most difficult of any of the phases of memory. But all agree that the faculty may be developed by practice and interest. There have been instances of persons having this faculty of the mind developed to a degree almost incredible; and other instances of persons having started with an aversion to figures and then developing an interest which resulted in their acquiring a remarkable degree of proficiency along these lines.
Many of the celebrated mathematicians and astronomers developed wonderful memories for figures. Herschel is said to have been able to remember all the details of intricate calculations in his astronomical computations, even to the figures of the fractions. It is said that he was able to perform the most intricate calculations mentally, without the use of pen or pencil, and then dictated to his assistant the entire details of the process, including the final results. Tycho Brahe, the astronomer, also possessed a similar memory. It is said that he rebelled at being compelled to refer to the printed tables of square roots and cube roots, and set to work to memorize the entire set of tables, which almost incredible task he accomplished in a half day—this required the memorizing of over 75,000 figures, and their relations to each other. Euler the mathematician became blind in his old age, and being unable to refer to his tables, memorized them. It is said that he was able to repeat from recollection the first six powers of all the numbers from one to one hundred.
Wallis the mathematician was a prodigy in this respect. He is reported to have been able to mentally extract the square root of a number to forty decimal places, and on one