first paroxysm and in the subsequent intervals, and to continue its use as a precaution against the recurrence of the fever. Little remained to be added to these practical indications; they were empirical, indeed and they are empirical still. The profession is not even sure whether quinine acts by breaking the recurrent habit of ague (as an anti-periodic), or otherwise. There are also the most conflicting statements as to whether the taking of quinine will ward off the attack of ague in passing through a malarious locality; there are a good many reasons for believing that quinine has no preventive or anticipatory action against the first onset of a remittent or intermittent fever, but the professional advice will probably be that quinine taken as a preventive can at least do no harm.
But it is when we leave the sphere of empirical experience, and enter the physiological and pathological workshops of the profession, that we realize most acutely how great is the disproportion, in this matter of malaria, between the opportunities of medicine and its achievements. Take, for example, the following sufficiently eclectic statement on the physiological actions of quinine:
Quinia, C20H24N2O2, one of the alkaloids of cinchona, in small doses accelerates the heart's action in the warm-blooded animal; in moderate doses it slows it; and in large doses it may arrest it, and cause convulsions and death. Research shows that its action is essentially upon the central nervous system. It destroys all microscopic animal organisms, apparently killing vibrios, bacteria, and amœbæ; but it seems to be without action on humble organisms belonging to the vegetable kingdom. It arrests the movements of all kinds of protoplasm, including those of the colorless corpuscles of the blood. It arrests fermentive processes which depend on the presence of animal or vegetable organisms, but it does not interfere with the action of digestive fluids.—(Quain's "Dictionary of Medicine," p. 35.)
There is here something far everybody; and, if we now go to the pathological workshop, we shall discover the beautiful adaptation of these varied actions of quinine to the various opinions that are entertained of the malarious fevers over which the drug has so powerful an influence. Is malarial fever a fermentive process, depending on the presence of animal or vegetable organisms? then quinine arrests such processes. Is malarial fever caused by a profound disturbance of the nervous mechanism which regulates the animal heat? then the action of quinine is "essentially upon the central nervous system." Nothing could be more accommodating, and nothing more unsatisfactory.
The theoretical notions about malaria form an instructive page of medical history. Until about 1823 it was always thought to be associated with marshes and swamps, but in that year Dr. William Fergusson brought to England numerous proofs that it occurred abundantly in elevated and rocky regions. Such evidences have gone on accumulating, and it is now well known that malaria has no necessary connection with the marsh. But the profession is still profoundly