ing one per cent of Quicklime ceased to grow. Cultivations which had been mixed for more than three hours, even if containing only one-half per cent Quicklime, showed no growth.
Further experiments with chemicals should have been made, but as my time was extremely limited I had to leave them to a future time.
The following is a short review of 'The Plague' generally. History shows us that Plague epidemics existed in the 14th century both in Asia and Europe and thousands of human beings perished. Since then from time to time, now here, now there, an epidemic has appeared, and until lately the disease almost seemed to have vanished from the face of the earth. This however was not so. In China it has existed to this day, especially in Yunnan, where it occurs every year in an endemic form. From the latter place it was imported to Canton and from Canton for the first known time has reached Hongkong.
This recent outbreak has given us opportunity for studying this disease—a cause of mystery for centuries—with the means which modern science places in our hands.
The principal symptoms of the disease now ravaging Hongkong are the following:—After the period of incubation, which lasts from 3 to 5 days (possibly a little longer and some doctors say as long as eight days), the patient complains of high fever and swelling of one or more of the lymphatic glands (Buboes). These swellings may antedate, coincide with, or follow the rise in temperature, and are accompanied by severe pain. The most common gland affected is one of the femoral chain—next an inguinal, next axillary, and sometimes a cervical gland is affected. The tongue is coated with a greyish-white or dark brown heavy fur. There is commonly headache, also delirium; the heart is generally affected; occasionally vomiting and diarrhea are present (not frequently the two last conditions, which are generally forerunners to a fatal issue).
In patients who survive the onset of the disease the temperature does not fall until a week has passed, and convalescence is a slow process.
Sex and age make no difference in the disease; men and women, infants and old people are attacked equally.
If in such a case as described, the blood be examined, the before-described Bacilli, in greater or lesser numbers, will be found present. (In 30 patients I obtained 25 positive results, and two of my subjects which were without Bacilli were subsequently proved not to be suffering from the plague at all.)
As indicated before, it is not always an easy matter to demonstrate the presence of the Bacilli directly in the blood of many patients—they are present sometimes in such small numerical strength that only after examining several slides can they be discovered. In order to be safe, not only must the blood of a suspected plague patient be examined, but a cultivation should also be made.
In the buboes the Bacilli always occur in the form of pure cultivations, but it is obviously not always easy to procure a specimen of bubo-contents from the living subject.
The question arises,—"Is it possible to make a diagnosis of Bubonic Plague from examination of the blood of the suspect?" In many cases, Yes! But a good deal of bacteriological practice is required or such diagnosis is impossible.
It is a well-known fact that so far, amongst infectious diseases produced by bacilli, only two micro-organisms have hitherto been found in human blood, viz., the bacillus of anthrax and the spirochætæ of relapsing fever (we do not include the plasmodia of malaria). Here in the blood of human beings suffering from bubonic plague we have a new bacillus possessing the following qualities:—
1st. This Bacillus occurs in the blood, in buboes, and in the internal organs of the plague-stricken ONLY.
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