While we have at the present time no means of inoculation that will permanently protect against infection from diphtheria, still it is not of such an infectious character as smallpox, as the cases are usually limited to children, and its spread may therefore be more easily prevented. Not only should children who have had diphtheria be prevented from returning to school until infection is no longer possible, but other children of the same household should also be kept at home. A few years ago a certain school in this city was rarely without a case of diphtheria among its pupils for many months. I am convinced that had the principal of the school or the parents insisted upon the other children of the infected household remaining at home, the spread in this direction would have been arrested and much suffering avoided. When a patient has recovered from diphtheria, thorough disinfection is a most important measure. Unfortunately, however, many persons consider it a hardship if articles which can not be disinfected are destroyed, and many will even use every endeavor to prevent the representatives of the Board of Health from carrying out their regulations. In this way the germ of the disease remains on the premises, and under suitable conditions again finds another victim in the household. To illustrate this, I recall an instance some years ago in which I was called in consultation to see a most malignant case of diphtheria. The little patient fortunately recovered, and the premises were thoroughly disinfected, the parents being anxious to avoid any repetition of the dreaded malady. Five months later, however, a younger child became ill, and was found to have diphtheria. In view of the vigorous efforts which had been made to disinfect the house thoroughly, and of the fact that the child could not have contracted it elsewhere, not having left its home for several weeks, the cause at first appeared a mystery. Careful inquiry, however, soon elicited a fact which clearly explained the case. The first patient had used a mouth-organ just before its illness, and when this was abandoned, the toy was carelessly thrown on the top of a bookcase, the nature of the child's illness at the time not being known. The second child, just before its illness, had accidentally found this toy and used it frequently. This experience explains the necessity of disinfection in all its details, and also illustrates the tenacious character of the germ which produces this disease.