The objects that are put away for safe-keeping differ in one respect from those things which are stored away in the memory. The material object is the same, whether we visit and inspect it from day to day or not. The banker's dollars are not increased in fineness or value by his handling them over carefully every day. Not so with intellectual coin. The more frequently we re-examine our knowledge and pass it under review, the more does it become fixed in its character, the more full and exact in its proportions. Handling it does not wear it out. Even giving it away does not diminish it. In short, so far as the cultivation of the memory is concerned, the next best thing we can do, after reducing our knowledge to due order, is to give it a frequent and thorough re-examination. Constant, almost endless repetition is the inexorable price of sound mental accumulation. A distinction is to be made between memory as a power of the mind and the remembrance of particular facts. One or two examples will illustrate this difference. The late Dr. Addison Alexander, of the Theological Seminary at Princeton, had memory as an intellectual power to a degree almost marvellous. The following instance may be cited. On one occasion, a large class of forty or fifty were to be matriculated in the Seminary in the presence of the Faculty. The ceremony of matriculation was very simple. The professors and the new students being all assembled, in a large hall, each student in turn presented himself before the professors, had his credentials examined by them, and if the same proved satisfactory, entered his name in full and his residence, in the register. When the matriculation was complete and the students had retired, there was some bantering among the professors as to which of them should take the register home and prepare from it an alphabetical roll,--a work always considered rather tedious and irksome. After a little hesitation, Dr. Alexander said, "There is no need of taking the register home; I will make the roll for you;" and, taking a sheet of paper, at once, from memory, without referring to the register, and merely from having heard the names as they were recorded, he proceeded to make out the roll, giving the names in full and giving them in their alphabetical order. This was a prodigious feat of pure memory; for in order to make the alphabetical arrangement in his mind, before committing it to paper, he must have had the entire mass of names present in his mind by a single act of the will. Some of the wonderful games of chess performed by Paul Morphy are dependent in part upon a similar power of memory, by which the player is enabled to keep present in his mind, without seeing the board, a long series of complicated evolutions, past as well as prospective and possible. The same is true of every great military strategist.