HE MUST HAVE A THOROUGH KNOWLEDGE OF THE STANDARDS.--He must have more than the traditional knowledge of the trade that he is to teach; he must have also the knowledge that comes only from scientific investigation of his trade. This knowledge is ready and at hand, in the standards of Scientific Management that are available to all for study. HE MUST BE CONVINCED OF THE VALUE OF THE METHODS HE TEACHES.--The teacher must also have an intimate acquaintance with the records of output of the method he is to teach as compared with those of methods held in high esteem by the believer in the old methods; for it is a law that no teacher can be efficient in teaching any method in which he does not believe, any more than a salesman can do his best work when he does not implicitly believe in the goods that he is selling. HE MUST BE AN ENTHUSIAST.--The best teacher is the one who is an enthusiast on the subject of the work itself, who can cause contagion or imitation of his state of mind, by love of the problems themselves. SUCH ENTHUSIASM CONTAGIOUS.--It is the contagion of this enthusiasm that will always create a demand for teachers, no matter how perfect instruction cards may become. There is no form or device of management that does away with good men, and in the teacher, as here described, is conserved the personal element of the successful, popular Traditional foreman. VALUABLE TEACHER INTERESTS MEN IN THE ECONOMIC VALUE OF SCIENTIFIC MANAGEMENT.--The most valuable teacher is one who can arouse his pupils to such a state of interest in the economic values of the methods of Scientific Management, that all other objects that would ordinarily distract or hold their attention will be banished from their minds. They will then remember each step as it is introduced, and they will be consumed with interest and curiosity to know what further steps can be introduced, that will still further eliminate waste. OBJECT-LESSON MAY BE "WORKING MODELS."--The object-lesson may be a "fixed exhibit" or a "working model," "a process in different stages," or "a micro-motion study film" of the work that is to be done. Successful and economical teaching may be done with such models, which are especially valuable where the workers do not speak the same language as the teacher, where many workers are to perform exactly similar work, or where the memory, the visualizing and the constructive imagination, are so poor that the models must be referred to constantly. Models naturally appeal best to those who take in information easiest through the eyes.