PATHOGENIC ANAEROBIC BACILLI. 485 



bouillon made from one and one-fourth kilogrammes of lean beef, with 

 the addition of twenty-five grammes of peptone, they obtained 1.7118 

 grammes of hydrochlorate of tetanin. This proved fatal to white 

 mice in six hours in the dose of 0.05 gramme, and a dose of 0.105 

 gramme caused characteristic tetanic convulsions and death within 

 an hour. The bacteriologists last named also obtained from their 

 cultures the tetanotoxin of Brieger. Two mice were inoculated sub- 

 cutaneously with 0.003 gramme of this substance ; one died at the 

 end of five hours without the development of tetanic symptoms ; 

 the other survived. In addition to these substances, indol, phenol, 

 and butyric acid were demonstrated to be present in cultures of the 

 tetanus bacillus. 



According to Kitasato, the tetanus bacillus does not become at- 

 tenuated in its pathogenic potency by cultivation in artificial media, 

 as is the case with many other pathogenic bacteria. The more 

 recent researches of Brieger and Frankel, and of Kitasato, show that 

 the toxic ptomaine discovered by Brieger in 1886 is not the substance 

 to which cultures of the tetanus bacillus owe their great and pecu- 

 liar pathogenic power. The distinguished German chemist and his 

 associate have succeeded in isolating from tetanus cultures a toxal- 

 bumin which is far more deadly than tetanin. 



Pathogenesis. The experiments of Kitasato (1889) show that 

 pure cultures of the tetanus bacillus injected into mice, rabbits, or 

 guinea-pigs produce typical tetanic symptoms and death. As the 

 presence of this bacillus at the seat of injury, in cases of tetanus in 

 man, has now been demonstrated by numerous observers, there is 

 no longer any question that tetanus must be included among the 

 traumatic infectious diseases, and that the bacillus of Mcolaier and 

 of Kitasato is the specific infectious agent. Kitasato's recently pub- 

 lished experiments (1890) show that cultures of the tetanus bacillus 

 which have been sterilized by filtration through porcelain produce 

 the same symptoms, and death, in the animals mentioned, as result 

 from inoculation with cultures containing the bacillus. It is evi- 

 dent, therefore, that death results from the action of a toxic sub- 

 stance produced by the bacillus. This is further shown by the fact 

 that the bacillus itself cannot be obtained in cultures from the blood 

 or organs of an animal which has succumbed to an experimental in- 

 oculation with an unfiltered culture ; but the blood of an animal 

 killed by such an inoculation contains the tetanus poison, and when 

 injected into a mouse causes its death with tetanic symptoms. 



When a platinum needle is dipped into a pure culture of the 



tetanus bacillus and a mouse is inoculated with it subcutaneously, 



the animal invariably falls sick within twenty-four hours and dies of 



typical tetanus in two or three days. Rats, guinea-pigs, and rabbits 



41 



