The chief enemy of health among school children (and older persons as well) is the accumulation and retention of waste matter and gases in the intestinal canal, where are generated ptomaine, toxic, and other poisons which enter into the system, resulting in self-poisoning or auto-intoxication. What do we mean by school hygiene? Is it only the school building, or the external appearance of the children, their eyes, teeth, mouth, nose, hands? What about the coated tongue, foul breath, fouler stomach, and putrefaction of the contents of their intestines? A human being is only an extension of his gastro-intestinal apparatus, hence it is very essential that such apparatus should be in a hygienic state to ensure his physical and mental resistance and efficiency being at their normal strength. There is one symptom that causes more sickness and suffering from infancy to old age than all others combined--that is, constipation with its attending putrefaction and foulness of digestive organs. Only a small percentage of people escape its baneful effects or the secondary diseases induced by fecal and mucus auto-intoxication. Such a common primary symptom must have, necessarily, a common exciting cause or origin. Through many years of clinical experience as a gastro-enterologist and proctologist, we have found that inflammation of the anus, rectum, and sigmoid flexure is the frequent or common cause of constipation. Observation has demonstrated that a soiled diaper is the exciting cause of Proctitis and Sigmoiditis in the beginning. Examination of one hundred children of the “defective class” would show most of them suffering from chronic Proctitis and Sigmoiditis, with some degree of constipation and auto-intoxication, and even of those classed as “healthy school children” a large percentage would show the same conditions. The continuous invasion of the neighboring tissues by the disease, the increasing auto-intoxication and constipation, the on-coming malnutrition, and anemia, the gradual emaciation, are all the while lessening the vitality and power of bodily resistance of their victims. The early inception of the malady and its insidious progress, with the symptoms and diseases resulting, easily deceives the victim as well as the parents and medical advisers, until the long-pent-up virulence breaks forth, showing itself in every part of the tabernacle of the spirit of man, when the removal of the primary cause does little or no good.