BACILLUS TETANI 613 



temperature of the room, or at this temperature in the desic- 

 cator over sulphuric acid, it is not destroyed. 



"Diffuse daylight diminishes the intensity of the poison. 

 Its intensity is preserved when kept in the dark. 



"Direct sunlight robs it of its poisonous properties in 

 from fifteen to eighteen hours. 



" Its activity is not diminished by diluting a fixed amount 

 with water or nutrient bouillon. 



"Mineral acids and strong alkalies lessen its intensity." 



The chemical nature of this poison is not positively known, 

 but its designation "Toxalbumen" is probably a misnomer, 

 for its reactions do not warrant its classification with the 

 albumins in the sense in which the word is commonly used. 

 When obtained in a concentrated form, its toxic properties 

 are seen to be altered by acids, by alkalies, by sulphuretted 

 hydrogen, and by temperatures above 70 C. Even when 

 carefully protected from light, moisture and air, it gradually 

 becomes diminished in strength, doubtless due to the forma- 

 tion of "toxons" and "toxoids," analogous to those observed 

 by Ehrlich in deteriorating diphtheria toxin. When freshly 

 prepared its potency is almost incredible, 0.00005 milligrams 

 being sufficient to cause fatal tetanus in a mouse weighing 

 15 grams. 



The studies of Madsen 1 demonstrate it to consist of two 

 physiologically distinct intoxicating compounds; the one, 

 a solvent of erythrocytes a "tetanolysin;" the other, a 

 specific irritant which, through its influence upon the central 

 nervous system, 2 accounts for the phenomena by which 



1 Ueber Teanolysin, Zeitschrift fur Hygiene und Infektionskrankheiten, 

 1899, Bd. xxxii, S. 214. 



2 See paper by Wassermann and Takaki, Berliner klinische Wochen- 

 schrift, 1898, No. 1, S. 5. 



