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lies in failing to take account of the fact that the exposure to risks of infection may not be uniform in all species. In point of fact, the difference between sheep and cattle in this respect is enormous, and quite sufficient to account for the apparent immunity of the former species.

In cattle most cases of tuberculosis are due to the inhalation of tubercle bacilli floating in the air of the buildings in which they are stalled. The air thus becomes contaminated by the desiccation of mucus expelled from the lungs of tuberculous subjects, and, doubtless, in some cases by similar desiccation of other matters, such as fa:ces or urine, containing bacilli. Now, if that is the common mode of infection in cattle-and there can hardly be any doubt on this point-the fact that sheep are much less frequently attacked need excite no surprise, even although we assume that they are not by nature less susceptible to infection than cattle. In short, there is every reason to suppose that the main cause of the excessi,·e preval­ence of tuberculosis in cattle is not their great natural susceptibility to illfection but their indoor existence, which mUltiplies the chances of infection. Conversely, the escape of sheep is not due to natural resist­ance to infection, but to the fact that their outdoor life minimises the risk of infection. Tuberculosis is a disease of animals that have to spend the whole or a great part of their existence in houses, and the fact should never be lost sight of in considering means of prevention.

THE PREVENTION OF JOINT-ILL.

IT may be in the recollection of our readers that on a recent occasion we were taken to task for having in an editorial article recommended the adoption of Listerian methods in the castration of horses. At the risk of being a second time reproached with being" like the Athenians of old, 'too eager to tell of some new thing,' and to accept it as an improvement on the old," we desire to refer with approval to the article which occupies the first place in the present number.

It is often said that the first step towards the discovery of a remedy for any disease is the discovery of its cause, but to that rule there are both fortunate and unfortunate exceptions. As fortunate excep­tions one may reckon those instances in which an effective method of prevention or treatment is known although the cause of the disease is still obscure, and as unfortunate those in which the elucidation of the cause has not as yet been foIIowed by the introduction of reliable ineans of combating the morbid process, either by way of prevention or cure. Joint-ill, however, is a disease which is in conformity with the rule, for the discovery that the articular inflammations were metastatically derived from a primary focus in the stump of the umbilical cord pointed in the plainest manner to a method of

EDITORIAL ARTICLES.

prevention, especially in the case of foals. If the poly-arthritis was always secondary to suppuration at the umbilicus, then, clearly, the indication was to secure an aseptic cicatrisation of the umbilicus.

I t is possible that there are still to be found veterinary surgeons who believe that joint-ill is due to such causes as cold, improper dieting of the mother, etc., and it is certain that a systematic treatment of the navel as a means of prevention is seldom or never carried out in this country. The neglect of such precautions may be due not to any misapprehension regarding the true nature of the affection but to a conviction that the results obtained would not be commensurate with the trouble involved in carrying out a strictly antiseptic treatment of the umbilical region. It is, of course, true that the proportion of deaths from pya:mic joint disease among the total number of foals born every year is very small, but to the owner of a valuable foal dead from this cause that would probably in the mouth of a veterinary surgeon appear a very insufficient reason for not having advised the adoption of preventive measures.

The method of dressing the umbilical stump recommended by Herr Gmelin, as he himself says, is not very simple, but if it is efficacious­and the results obtained in the Marbach stud appear to warrant that conclusion-probably many stock-owners would not grudge the necessary expense. At any rate, when a veterinary surgeon is called to a case of joint-ill it might not be a bad course to let the owner know that veterinary skill, although powerless to cure the disease, is quite competent to prevent it.

SWINE ERYSIPELAS.

THE paper by Dr Murray and Mr Stephenson on "Swine Erysipelas" (p. 50), and the one on the same subject published in last issue of the Journal, raise some rather important questions. The observations recorded in these articles make it absolutely certain that we have in this country, besides swine fever, another very formidable scourge of the pig species. That this swine erysipelas is a disease as fatal and infectious as swine fever perhaps does not appear from the few cases referred to in the two articles in question, but that such is the case the statistics obtainable from France, Germany, and other Continental States fully prove. To reconcile this with the fact that the occurrence of the disease has not long ago been detected, one must conclude either that the disease is of recent importation here, that our swine are less susceptible to it than Continental breeds, or that it has been over­looked owing to its being mistaken for swine fever. Time will show which of these hypotheses is the correct one, but the one last mentioned seems much the most probable.

By way of showing what a formidable plague the disease is in other