402 BACTERIOLOGY. 



" By drying at the temperature of the body under 

 access of air the poison is destroyed, but by drying at 

 the ordinary temperature of the room, or at this tem- 

 perature in the desiccator over sulphuric acid, it is not 

 destroyed. 



" Diffuse daylight diminishes the intensity of the 

 poison. Its intensity is preserved for a much longer 

 time 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 inten- 

 sity." 



The chemical nature of this poison is not positively 

 known, but according to the recent observations of Brie- 

 ger and Cohn it is not to be classed with the albumins in 

 the sense in which the word is commonly used. When 

 obtained in a pure, concentrated form its toxic proper- 

 ties are seen to be altered by acids, by alkalies, by sul- 

 phuretted hydrogen, and by temperatures above 70 C. 

 Even when carefully protected from light, moisture, and 

 air it gradually becomes diminished in strength. When 

 freshly prepared by the methods of the authors just 

 cited its potency is almost incredible, 0.000,05 milli- 

 gramme beinsj sufficient to cause fatal tetanus in a mouse 

 weighing fifteen grammes. 



THE BACILLUS OF MALIGNANT (EDEMA. 



The bacillus of malignant oedema, also known as the 

 vibrion septique, is another pathogenic form almost every- 

 where present in the soil. In certain respects it is a 



