Vidocq, the celebrated French detective, is said to have never forgotten a face of a criminal whom he had once seen. A celebrated instance of this power on his part is that of the case of Delafranche the forger who escaped from prison and dwelt in foreign lands for over twenty years. After that time he returned to Paris feeling secure from detection, having become bald, losing an eye, and having his nose badly mutilated. Moreover he disguised himself and wore a beard, in order to still further evade detection. One day Vidocq met him on the street, and recognized him at once, his arrest and return to prison following. Instances of this kind could be multiplied indefinitely, but the student will have had a sufficient acquaintance with persons who possess this faculty developed to a large degree, so that further illustration is scarcely necessary.

The way to develop this phase of memory is akin to that urged in the development of other phases—the cultivation of interest, and the bestowal of attention. Faces as a whole are not apt to prove interesting. It is only by analyzing and classifying them that the study begins to grow of interest to us. The study of a good elementary work on physiognomy is recommended to those wishing to develop the faculty of remembering faces, for in such a work the student is led to notice the different kinds of noses, ears, eyes, chins, foreheads, etc., such notice and recognition tending to induce an interest in the subject of features. A rudimentary course of study in drawing faces, particularly in profile, will also tend to make one "take notice" and will awaken interest. If you are required to draw a nose, particularly from memory, you will be apt to give to it your interested attention. The matter of interest is vital. If you were shown a man and told that the next time you met and recognized him he would hand you over $500, you would be very apt to study his face carefully, and to recognize him later on; whereas the same man if introduced casually as a "Mr. Jones," would arouse no interest and the chances of recognition would be slim.