ANTHRAX. 277 



cent, solution if these reagents are to have any lethal effect 

 on them. Carbolic acid in oil five per cent, solution 

 had little more, if any, effect than pure olive oil. The spores 

 remain alive, for an indefinite period almost, in a five per cent, 

 solution of olive oil. Sulphurous acid vapour in the propor- 

 tion of one to one hundred of air kills the bacilli in half an 

 hour, but the spores resist the same antiseptic for seventy-two 

 hours. Corrosive sublimate in one per mille of water suffices 

 to kill spores by simply wetting them. 



These tests of the vitality of the spores, however, were 

 made by inoculating them into gelatine after they had been 

 treated with the antiseptic. If, in place of inoculating into 

 a nutrient medium of this nature, the spores are introduced 

 into the circulating blood of a living animal, it has been found 

 by Klein that it requires much longer exposure and much 

 stronger solutions to hinder the development of the spores 

 into bacilli and prevent the production of anthrax. 



We have already stated that the organism cannot con- 

 tinue its growth at any temperature above 45 C., but it may 

 still remain alive up to about 60 C. if this temperature be 

 not continued for too long a period, the spore-bearing bacilli, 

 though themselves killed at this temperature, leave their 

 spores, which will withstand a temperature of 100 C. if 

 continued only for a short time, and start into life and into 

 active vegetative growth when again placed under suitable 

 conditions. The only other physical condition that appears 

 to be fatal, or at any rate injurious, to anthrax spores is 

 strong sunlight ; this appears to deprive them in whole or 

 in part of their powers of further development in a most 

 remarkable manner, always causing distinct attenuation of 

 their pathogenic virulence before completely destroying 

 them. 



The best way of maintaining cultures of anthrax bacillus is 

 to take a drop of anthrax blood, sow it on a potato or agar-agar, 

 allow it to grow there for several days at about 30 C. until 

 spores are well developed, triturate a small quantity of the 

 growth with some distilled water, place a number of silk 

 threads which have previously been sterilized by heat in this 

 mixture, and then dry them carefully, cut into short lengths, 

 and keep them in a stoppered bottle or in a plugged test tube. 

 From these threads cultivations may be made on almost any 

 artificial nutrient medium. In addition to the media already 



