Before quitting the subject of the influence exerted by Climate, we are bound to return once more to the question, _in what relation did contagion_, if contagion there was, _stand to this climatic influence?_ The existence of contagion in the case of gonorrhœa is certified by the passage of _Galen_ already quoted by Naumann, which we propose later on to give in full, besides being implied long before by the law of purification of the Mosaic Books. So far as ulcerous formations, condylomata and skin-affections such as _mentagra_ etc., are concerned, proof is supplied by the facts we have previously given. According to more modern experience all forms of contagion exhibit in Southern countries a more fugitive type than elsewhere and spread with proportionately greater readiness. Whereas in such as are naturally fugitive, the intensity may for that very reason be less injurious, fixed and stable forms of contagion on the contrary must obviously lose in strength, at any rate so far as their local effects go. They will be the less able to make good a lodgement in the organism, from the fact that, stimulating the latter as they do to a general activity, they are the more readily resisted and prevented by this very state of enhanced activity. For just as, speaking generally, chronic complaints, uncomplicated by fever, can only be removed by artificially setting up a feverish condition, that is to say by calling on the organism as a whole to share in the local manifestations of disease. Precisely the same is true of local affections set up by any fixed and stable contagion, and so the removal of the actual contagion can only be successfully brought about either by direct decomposition and destruction of the affected tissue or by metamorphosis into a fugitive form.