Iodine preparations of various forms are very commonly used topically as an adjunctive treatment to internal medication in the treatment of a number of acute pathological conditions in veterinary patients. The object in adding local iodine applications to the handling of such conditions is varied. In some cases, the object of the practitioner is to hasten the correction of certain well-marked local manifestations of the disease with which the patient is afflicted. In other instances, the aim of the practitioner is toward the prevention of these local manifestations. Occasionally, in a certain type of pathological conditions, the practitioner intends, by the use of topical iodine applications, to enhance the internal treatment being aimed at symptoms whose entire nature is local in character and confined to a very limited portion of the anatomy. In every case coming under this sub-classification, the effect that the iodine applications have--the only effect that they are able to accomplish--is one of amelioration; they can have no direct curative effect here. While the various conditions that are included under this head will be fully discussed in following chapters, I will point to the use of topical iodine medication in the handling of a case of parotitis as an illustration. While regional applications of iodine are the rule, in the handling of cases of this affection in veterinary patients, no one at all versed in the condition as it occurs in practice would give the credit of ultimate cure to the iodine applications. But all will admit readily that, while the internal treatment indicated by the pathology of the condition is correcting the lesion _per se_, the regional applications of iodine do contribute materially to a smooth termination of the case in that they do, without question, lessen the possibility of abscess formation, relieve the pain, and hasten resolution. The conditions included under this heading form, in great part, that class of cases to which reference was made in the beginning of this treatise, namely, those in which iodine treatment is largely used under circumstances and in conditions that lack almost every scientific indication for its application. Yet, it is in these very conditions, and under these very circumstances, that topical applications of iodine are frequently most salutary in effect. And this effect is enhanced to the degree, as will be pointed out later, to which the practitioner becomes adept in the selection of the proper form or preparation of iodine for the particular case in hand. 3. REGIONAL IODINE APPLICATIONS FOR THE CURE OF CHRONIC PATHOLOGICAL CONDITIONS.