378 MICRO-ORGANISMS AND DISEASE [chap, 



oedematous fluid contain spores, particularly if the examina- 

 tion be delayed after death. The oedema bacillus is of great 

 importance, since by the observations and experiments of 

 Chauveau and Cornevin, Brieger, and others, it has been 

 shown that surgical gangrene (progressive gangrenous em- 

 physema) in the human subject is caused by the same bacillus. 

 It seems that many a soil containing putrid animal substances, 

 such as hay dust, rag dust, offensively smelling filth of dustbins, 

 offensively smelling exudations, gangrenous discharges, &c., 

 contains the oedema bacillus or its spores. Horses, pigs, 

 and sheep are susceptible to this malignant cedema, pro- 

 vided large doses are inoculated ; cattle are not susceptible. 

 As mentioned above, guinea-pigs are the best experimental 

 animals, since inoculation produces a typical, emphysemat- 

 ous, spreading oedema, with fatal result. 



Pasteur has studied this septicaemia on guinea-pigs, and 

 it is also called Pasteur's septicaemia, and the bacillus is 

 called by him vibrio septique. Roux and Chamberland 

 have demonstrated in the broth cultures of this microbe 

 chemical substances which separated by filtration from the 

 bacilli and injected into animals cause a transitory illness 

 proportionate to the amount injected, and hereby confer 

 immunity against the injection of the virulent bacilli them- 

 selves. But this immunity does not last long, and is not 

 produced if too small quantities are used. 



Fliigge has isolated from recently manured garden earth 

 a pseudo-malignant cedema bacillus which resembles Koch's 

 malignant oedema bacillus, but is non-pathogenic. 



2. Bacillus tctani. — Carle and Rattone {Giorn. dell. r. 

 Accad. d. Med. Torina, 1884) were the first to show that 

 tetanus is a communicable disease. They succeeded in 

 producing typical tetanus, terminating fatally, by inoculating 

 into rabbits pus taken from the ulceration of a human 



