They are baffled in the discovery of a serum wherewith to fight the disease. And in all their work, as yet, they have found no clue, no cure. Sometimes there have been blazes of hope, theories of causation and much heralded cures, but every time the darkness of failure quenched the flame. A doctor insists that the cause of leprosy is a long-continued fish diet, and he proves his theory voluminously till a physician from the highlands of India demands why the natives of that district should therefore be afflicted by leprosy when they have never eaten fish, nor all the generations of their fathers before them. A man treats a leper with a certain kind of oil or drug, announces a cure, and five, ten, or forty years afterwards the disease breaks out again. It is this trick of leprosy lying dormant in the body for indeterminate periods that is responsible for many alleged cures. But this much is certain: _as yet there has been no authentic case of a cure_.
Leprosy is _feebly contagious_, but how is it contagious? An Austrian physician has inoculated himself and his assistants with leprosy and failed to catch it. But this is not conclusive, for there is the famous case of the Hawaiian murderer who had his sentence of death commuted to life imprisonment on his agreeing to be inoculated with the _bacillus lepræ_. Some time after inoculation, leprosy made its appearance, and the man died a leper on Molokai. Nor was this conclusive, for it was discovered that at the time he was inoculated several members of his family were already suffering from the disease on Molokai. He may have contracted the disease from them, and it may have been well along in its mysterious period of incubation at the time he was officially inoculated. Then there is the case of that hero of the Church, Father Damien, who went to Molokai a clean man and died a leper. There have been many theories as to how he contracted leprosy, but nobody knows. He never knew himself. But every chance that he ran has certainly been run by a woman at present living in the Settlement; who has lived there many years; who has had five leper husbands, and had children by them; and who is to-day, as she always has been, free of the disease.