In the health field the topics have often been very general, as “Child Welfare” or merely “Public Health.” One public health car, which seemed to be fairly typical, carried exhibits on the prevention and cure of tuberculosis, care of babies, the duties of the school nurse, food adulteration, communicable diseases, playgrounds, venereal diseases, and a description of the functions of the State Health Department. The more inclusive and thus less specific the topic the more vague and general will be the talk about it afterward by those who visited the train. A reason sometimes given for presenting varied and general topics is that the purpose is not so much to give definite information which will be remembered and acted on, as to impress people with the scope and importance of the subject. For example, the visitors to a public health car in which many phases of the subject are touched upon may carry away a conviction that public health work is important to the community and should be supported although their ideas of it were very vague. This result may satisfy the purpose of some campaigns, but more often directors who present a variety of topics hope that something about each will be remembered; and there is reason for believing that their hope will not come as near to realization, or at least that the information will not be of as great utility, as it might if the subjects were fewer and more specifically treated. Another argument frequently brought forward in favor of including several topics is that all sorts of people will visit the train or truck, and while one will be interested in one subject others will be more interested in something else. When those in charge of the program are meeting only a few people at a time, they can talk separately to each visitor about special problems, but the brief stops made on most tours require the message to be presented to a large group at one time or at least in quick succession, so that in practice it usually happens that all the visitors see and hear the same things. In this case the more closely a single and concrete topic is adhered to, the more hopeful campaigners may be that what is said or displayed will be remembered. An equally important reason for limiting the number of topics is the desirability of having your whole audience get the same message. In connection with the Wheat Specials, for example, not alone should the farmer and the farmer’s wife and the farmer’s children be informed about the wheat problems of the locality, but the local banker and business man stand in need of much the same information. The preacher and the doctor will help to spread the doctrine, and the school teacher can make good use of what he learns. The more nearly the entire community, young and old, understands and is interested in the same message, the more likely that the desired results will follow.