depend much on the attention given to what is to be remembered; the third on the number, variety, and arrangement of associations by which it may be re-called. There are minds on which most impressions are so slight that they are soon forgotten. Others who have learnt and retained much, do not remember things at the right time. Few have memories so quick, retentive, and ready, as not to need some special culture; and there are none whose memories may not be improved by attending to what is most important, and forming associations to aid recollection. Arbitrary arrangements to aid in recalling dates, words, and facts which have no natural connection, are occasionally of use for a time; but natural connections are more lasting, and are on every account to be preferred when attainable. There seem to be some variety of memory—a special aptitude for remembering words, or numbers, or facts, or arguments, or voices, or faces. There is some difference in natural susceptibility; but most of the differences in memory are to be attributed to the degree of attention given to various objects, and to habits of observing and thinking." After reading a book or an article, or an item of information from any reliable source, it is a good plan, before turning your attention to other things, to give two or three minutes' quiet thought to the subject that has just been presented to your mind; see how much you can remember concerning it; and, if there were any new ideas, instructive facts, or hints of especial interest that impressed you as you read, force yourself to recall them. It may be a little troublesome at first, until your mind gets under control and learns to obey your will, but the very effort to think it out will engrave the facts deeply upon the memory—so deeply that they will not be effaced by the rushing in of a new and different set of ideas; whereas, if the matter be given no further consideration at all, the impressions you have received will fade away so entirely that within a few weeks you will be totally unable to remember more than a dim outline of them. The chief use of a system of mnemonics is to induce a person to pay the utmost regard to the natural laws of memory. With persons differently constituted no particular system can be expected to suit the requirements of each;
