1881.] 



MICROSCOPICAL JOURNAL. 



63 



from this fact that I hope to convince 

 my readers of the connection between 

 the Bacillus anthracis and the con- 

 tagium of charbon. It is the line of 

 argument originally used by Koch, 

 and to me it seems to be a perfect 

 demonstration. 



By the cultivation of this organism 

 on growing slides, it was found that 

 it could not form spores unless the 

 atmospheric air was freely admitted ; 

 it also required for this purpose a 

 temperature above 12° (53.6° F.). If 

 the conditions of temperature, ventil- 

 lation and concentration of nourish- 

 ment were such that spores could 

 not be formed, the rods perished in a 

 few days. Now, it is a most interest- 

 ing question to know if the activity 

 of anthrax virus disappears with the 

 death of the rods when spores are not 

 formed, and if it is preserved inde- 

 finitely after the formation of such 

 spores ; and this question is doubly 

 interesting because the conditions 

 which affect the death of the rods be- 

 fore spore-formation are such as will 

 preserve unstable chemical com- 

 pounds. For instance, such a chemi- 

 cal substance is best preserved by 

 cold and protection from atmospheric 

 oxygen, as well as by drying ; but 

 these conditions prevent the forma- 

 tion of bacillus spores, and, hence, 

 lead to the death of the organism in 

 a very short time. 



If, therefore, the activity of fresh 

 charbon blood (which only contains 

 rods) is lost in a few days when ex- 

 posed to a low temperature, if it is 

 similarly lost when hermetically 

 sealed in glass tubes, or quickly dried, 

 especially if the loss of the activity 

 corresponds with the death of the 

 rods as determined by microscopical 

 observation and cultivation-experi- 

 ments, we have good evidence that 

 this activity is due to the Bacil- 

 lus. If we can go even beyond this 

 and prove that, when the spores are 

 once formed, the activity of the virus 

 is retained indefinitely though ex- 

 posed to cold, drying, putrefaction, or 

 when hermetically sealed, then, I 



maintain, we have a demonstration 

 that the Bacillus anthracis is the es- 

 sential cause of charbon, and that the 

 disease is due to no other agency. 



The following observations are pre- 

 sented as deciding the question : 



1. Blood and pieces of spleen, or 

 lymphatic glands, if dried as soon as 

 possible, after the death of the ani- 

 mal, soon lose their activity — the 

 smaller particles in twelve to thirty 

 hours, and all within five weeks. 

 When their inactivity is proved by 

 inoculation, cultivation-experiments 

 show that the Bacillus has perished. 



2. Such pieces of spleen, or glands, 

 which have been dried slowly in a 

 warm room, may retain their virulence 

 for certainly four years. These are 

 found to contain spores which may 

 be cultivated and which grow into fila- 

 ments that again form spores. 



3. If a bottle or test-tube is filled 

 with charbon blood, tightly corked, 

 and placed in an incubator at 35", it 

 very soon has an extremely disagree- 

 able odor of putrefaction, and within 

 twenty-four hours the rods have dis- 

 appeared, and the fluid is no longer 

 capable of producing the disease 

 when inoculated. This is evidently 

 due to the absorption of the available 

 oxygen by the septic bacteria, as may 

 be rendered clear by the next two 

 paragraphs. 



4. If a drop of such charbon blood 

 is placed on a slide and covered, and 

 the cover cemented air-tight, the rods 

 grow until the oxygen is exhausted, 

 as shown by the spectroscope, they 

 then remain stationary, and in a few 

 days become granular and disinte- 

 grate without forming spores. Such 

 blood is no longer capable of produc- 

 ing charbon. 



5. If the charbon blood be placed 

 in a watch-glass where there is free 

 access of air, and then kept in an in- 

 cubator at a proper temperature, 

 the putrefaction goes on as before, 

 and swarms of micrococci and bac- 

 teria appear. The development of 

 the Bacillus anthracis is accom- 

 plished, however, as though no other 



