any unpleasant effect: these last were organically sound before exposure, and the same after it. In external, visible parts, that are the seat of injury or disease, or that have been wounded by the surgeon's knife, and which are undergoing the process of tissue-repair, we see redness and congestion follow exposure to cold, and often enough hear the patient not only complain of pain, but date its commencement from known exposure, and express his belief—reached as if by instinct—that "cold had settled on the part."
Again, as young animals instinctively dread cold, and as Nature provides them means for warmth, so in individuals undergoing evolution of a pathological kind, we observe a like instinctive dread of exposure, and a liability to be easily "chilled," while means of protection are also instinctively resorted to. The extra quilt at night; the heavy wrapper during the day; the thick woolen under-garments; the flannel "chest-protector;" the late fires in spring, and early ones in autumn, so necessary for the comfort of the invalid—what are they but imitations of the means supplied by Nature for the preservation of warmth in young animals undergoing physiological development?
We have further proof that organs undergoing pathological evolution are liable to be disturbed by cold in the manner referred to, and also that the existence of the evolutionary process is itself one of the conditions without which (in the absence of others) inflammation, after exposure, would not take place, in the fact that attacks of inflammation occur repeatedly in the same organ. Thus, to take a familiar illustration, it has been long ago observed that some people are liable to repeated attacks of inflammation of the lungs (pneumonia). Andral records a case of a patient who had fifteen attacks in eleven years; Chomel has seen ten recurrences, J. P. Frank eleven, and Rust has recorded twenty-eight attacks, in the same individual A patient of Ziemssen's had four attacks in five years. It is also observed that, of the two lungs, the one first affected is most liable to suffer from subsequent attacks. In thirty-five cases of recurrence collected by Grisolle, the return of the disease was noted twenty-five times in the lung first affected. In the other ten, the disease changed sides (see Reynolds's "System of Medicine," vol. iii., p. 613).
The limits of the present paper precluding a very prolonged argument, we leave this part of the subject, hoping that what has been said is sufficient to account for the mortality of pathological processes which, we have said, are designedly conservative.
We may now further follow out the analogy between physiological and pathological evolution, by observing that structures undergoing pathological development (conservative organic modification), like those that are being developed physiologically, manifest an intrinsic tendency, when undisturbed in their progress, to pursue a fixed, typical course to their naturally-designed termination. When permitted to
