ANTHRAX AND ANTHRACOID DISEASES. 151 



to it, it forms a flocculent matter, which is deposited at the 

 bottom of the vessel. Collected on a filter and dried, this pre- 

 cipitate is still toxic. If would therefore appear that the active 

 or virulent element of anthrax resists absolute alcohol, and that 

 it resists oxygen, and that it is precipitated by alcohol and 

 soluble in water. It behaves itself something like diastase, 

 except that, whatever may be its nature, it can reproduce itself 

 to an indefinite extent ; while it is asserted by some authorities 

 that diastase cannot reproduce itself 



Putting aside the conclusions of Colin — that the bacilli are 

 simple transformation of the blood-corpuscles — we are left 

 between two sets of conclusions. Those of Koch and others 

 point to splenic fever being due to a minute organism possessing 

 wonderful powers of resistance and reproduction ; Bert's to 

 something independent of the presence or absence of animal or 

 vegetable organisms, and which resists the action of compressed 

 oxygen and absolute alcohol, which would, he asserts, kill every- 

 thing possessing life : this something he is of opinion is a sub- 

 stance analogous to diastase. 



Blood containing bacilli, if dried in very thin layers, by being 

 exposed to the air in a shady place, was found by Koch to lose 

 its virulence and its power of developing elongated fibres after 

 twelve to thirty hours. Thicker layers retained their powers 

 for two or three weeks ; and some still thicker for four or five 

 weeks. After a longer time they were never capable of pro- 

 ducing the disease. 



Koch also found that if the bacilli were deprived of air they 

 soon died. 



When rubbed up with the blood or aqueous or vitreous 

 humour of an ox, and placed in a well-closed glass vessel, there 

 quickly ensued an odour of putrefaction ; the bacilli disappeared 

 after twenty-four hours without the fibres enlarging, and lost 

 their infective power. That their death was due to the absence 

 of oxygen was shown by placing a drop of blood infected by the 

 bacilli under the microscope. Examined by the micro-spectro- 

 scope it gave the bands of oxy-hsemoglobulin ; the fibres in this 

 drop increased four or five times in length in three hours, but 

 after that time the oxygen was clearly used up, as the presence 

 of the absorption band of reduced ha?moglobulin proved. From 

 this moment the growth of the bacillar fibres ceased, although 

 true putrefaction had not set in. 



When the spores and bacilli are separated from the blood by 

 filtration, the blood is said to be rendered innocuous ; and when 

 pregnant animals become affected, or have been inoculated, the 

 blood of the foetus does not become diseased, and other creatures 

 can be inoculated with it and suffer no harm, the intervening 

 membranes acting the part of a filter. The bacilli also dis- 



