the great master, had nevertheless lighted their torches at his flame. I know of no surer index of a man's greatness than the measure of inspiration imparted by him.
Already Gayon had proved the bacterial cause of the decay of eggs. Koch had isolated the bacilli of tuberculosis and cholera. Traube had shown the like cause of ammoniacal fermentation; and upon the knowledge thus given, Van Tieghem and Gayon had devised their well-known treatment of diseases of the urinary organs. Lister had introduced asepsis, prior to which hospital statistics showed a mortality of 68 per cent, of cases of puerperal fever, gangrene and septicæmia generally incident to surgical operations. Accounts of surgical wards of army hospitals during our own civil war, typical, of course, of all that had preceded, with their perpetual agony, suppuration and horrible odors, read like a nightmare of insanity. A noted surgeon-teacher of that day said to his students, "When an operation seems necessary, think ten times about it; for too often when we decide upon an operation we sign the patient's death warrant." Another said, "He who shall conquer purulent infection will deserve a golden statue."
But to resume our catalogue: Behring and Kitasato, investigating lock-jaw, had discovered the microbe of tetanus, and ascertained the curious fact that although the patient was constitutionally affected the microbe was localized to the wound. They further found that the systemic effect of the disease was due to a toxin produced by the bacterium which was likewise fatally affected by the toxin. So that diluted solutions of the toxin not only constituted a remedy for the disease, but also a prophylaxis when administered in advance of infection. This was the first of the series of remedies known as anti-toxins.
Utilizing these results in the study of diphtheria, the combined labors of Richet and Herico, Boux and Yersin, Klebs and Loeffler, eventuated in 1894 in complete mastery of this disease, whose investigation had been inaugurated by Pasteur a dozen years before. Prior to the antitoxin method of treatment, diphtheria had justly been regarded as one of the worst scourges of our race, claiming a death-toll of 60 per cent, of all cases, and frequently leaving the survivors seriously injured for the remainder of their lives. At present, the mortality is about four per cent. And vaccination with the serum rendering the recipient immune to the disease for a period of about two months, epidemics of diphtheria may be entirely prevented by utilizing this prophylactic measure.
Closely connected with these researches on tetanus and diphtheria was a remarkable research brought out about this time by Metchnikoff, one of Pasteur's Russian pupils, in which he discovered the rôle of leucophytes, or white corpuscles of the blood. It appears that they constitute, so to speak, an army of defense, attacking and "eating up" in-
