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in animals are very similar to those found in anthrax and in edema malignum.
Pigeons do not appear to be susceptible to the influence of the Bacilli.
I made experiments, by feeding some mice and guinea-pigs with pure cultivations of the bacillus and with small pieces of the internal organs: the result was such animals perished in a few days, under the same symptoms as those which had been inoculated. In all the internal organs of animals so destroyed I found the Bacilli.
With the dust of dwelling houses from which the plague-stricken had been removed I made several experiments upon animals. Some of the animals died from Tetanus. In one case only a guinea-pig died with plague symptoms, and in this animal the same Bacilli were found in the internal organs as in those of plague patients who had succumbed.
These experiments with the dust from infected houses I shall certainly continue.
Many rats and mice, at present, die spontaneously in Hong-kong, I examined some of them. In the internal organs of a mouse I discovered the same Bacilli,
Power of Resistance of the Bacilli to Physical and Chemical Agencies.
Experiments with desiccation.-The contents of a Bubo in which the Bacilli were present in great numbers were wiped over cover glasses (perfectly cleansed by heat and alcohol), and some of the cover-glasses were dried in the air of a room at a temperature ranging from 28° C to 30° C. Others I exposed directly to the sun's rays, and from among them, after an exposure of from one, two and three hours (up to six days), I removed some parts, putting such portions in beef tea and placing them in the incubator. Those which had been standing in the room from one to thirty-six hours showed a pretty good growth in the incubator, but those which had been in the room for more than four days were unable
to show any growth even after one week's incubation. Those exposed directly to the sun were all destroyed after from three to four hours.
Further cultivations on serum were treated exactly like the contents of the bubo with very similar results.
Experiments with Heat.-Beef tea cultivations which had been heated for 30 minutes in a water bath up to 80° C. were destroyed at 100° C. in the vapour apparatus they were destroyed in a few minutes.
Chemicals-Carbolic Acid.-To every 10 cubic centimetres of beef-tea cultivations, which had been standing in the incubator from 2 to 3 days and had grown well, Carbolic Acid was added of a strength of one-half per cent of the whole-three-quarters per cent, and one per cent. They were afterwards well shaken and left at the ordinary temperature of the room. Of each of these cultivations a few drops were brought into sterilised beef-tea, after one, two and three hours, and left in the incubator with the following results.
Those cultivations which contained one-half per cent and three-quarters per cent Carbolic Acid and had been left standing in the room for one hour, grew in the incubator after two days. A cultivation however of one per cent which had been left standing for only one hour did not grow even after one whole week in the incubator.
Cultivations that had been mixed with only one-half per cent of Carbolic Acid and had been left standing for more than two hours did not show growth after one week in the incubator, neither did the other cultivations containing a greater percentage produce any growth.
Quicklime.-Experiments were made with Quicklime in exactly the same way as with Carbolic Acid, with the following results.
Those beef-tea cultivations which contained one-half per cent of Quicklime grew sparingly, after two hours; those containing
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