This theory as to the mode of production of acute rheumatism, and of the operation of cold, has other inherent weaknesses.
It means, first, that during half-an-hour's violent exercise there is formed in the systems of those of rheumatic constitution enough lactic acid to produce an attack of acute rheumatism ; second, that every time they take active exercise; such persons are liable to be laid up by that disease ; and, third, that they are saved from such a mis fortune only by the free action of their skins. Nature often bungles, but never to that extent.
But still more is involved in this belief; for, if we adopt it, we must also believe that during half-an-hour's violent exercise there is produced in the system enough lactic acid not only to give rise to acute rheumatism, but to keep up the symptoms of that disease for weeks, and to supply at the same time the excess of acid which is being eliminated during the whole period of the continuance of the malady. The mere statement of what is involved in this belief suffices to condemn it. For to suppose that the whole of the lactic acid which is required to produce an attack of acute rheumatism of several weeks' duration, with its accompanying profuse acid perspirations, could be produced in the system in the course of half an hour, is to presup pose the existence in the system, at the end of that half-hour, of a quantity of lactic acid, which (granting that acid to be the cause of the rheumatism) would produce the most acute inflammation of all the tissues of the body liable to rheumatic inflammation, and kill the patient by such inflammation in two or three days. On this view of its causation and nature all cases would be acute, and the disease would be more formidable and fatal than it is.
Again, if the poison of the disease were thus produced—if the whole of the materies morbi existed in the system at the ment of the attack—which would be the case if the above view were correct—we should find the symptoms of acute rheumatism developed, not gradually as is the case, but quickly, and very soon after the chill was applied ; we should have the joints affected, not in succession as is the case, but all at the same time, and also very soon after the chill ; and we should have the heart involved in every case. We
should find, too, that the free action of the skin, and consequent elimination of the acid, which characterize the disease, would be followed by relief of the pain; and that we know is not the case.
No, it is simply impossible that the gradual onset of the symp toms of acute rheumatism, the protracted and varying course of the disease, the shifting character of the joint inflammation, and the long continued hyperacidity of the secretions, can result from such an excess of lactic acid as could be produced in one or in a dozen hours' violent exercise. • In an attack of acute rheumatism there is eliminated by the skin alone in twenty-four hours a quantity of acid greater than is likely to exist in the system at the end of an hour's exercise.
It is erroneous and misleading to regard the excess of lactic acid, which undoubtedly does exist in acute rheumatism, as simply an accumulation. The use of this term, and the undue importance at tached to the operation of cold, have led to a misinterpretation of the phenomena observed. What we mean when we say that an excretory product accumulates in the system, is that it is being formed but not properly eliminated. But in acute rheumatism there is increased, and very greatly increased, elimination as well as increased formation; and this increased elimination goes on during the whole course of the malady. The most severe cases, those in which there is most suffering, and most of the characteristic joint affection, are also those in which the perspiration is most profuse and most markedly acid, and in which, therefore, the acid is most freely eliminated. We can not say that in such circumstances there is any accumulation of lactic acid in the system; for it is being eliminated in unusual quantity. Such increased elimination implies, not accumulation, but increased formation; and this is the phenomenon which calls for attention and for explanation. Increased formation of lactic acid is one of the es sential features of acute rheumatism; and no theory of that disease can be regarded as satisfactory, which does not recognize and ac count for this increase. This the lactic-acid theory fails to do.