ANTHRAX S3 



boiling for at least three minutes is necessary to insure the destruction 

 of the spores. Dry heat at 100 C. (212 F.) must be continued for 

 two hours in order to destroy the vegetative form, while three hours 

 at 140 C. (284 F.) are necessary to exterminate the spores. The 

 effect of direct sunlight on the two forms has been studied with vary- 

 ing and even contradictory results. This is easily understood when 

 we think of the many variable factors, such as thickness of layer, 

 intensity of light and temperature, entering into such experiments and 

 influencing the findings. According to Moment, drops of dried bouil- 

 lon cultures, with the air temperature at from 25 to 35 C. (77 to 95 

 F.), are destroyed when exposed to direct sunlight within from six to 

 fifteen hours in the vegetative form and after one hundred hours when 

 spores are present. The ordinary disinfectants, as generally used, 

 destroy the vegetative forms but are not certain in their action on 

 spores. Geppert found that after from two to three hours in corrosive 

 sublimate (1: 1,000) all spores are not killed. 



We may be thankful that this bacillus, armed as it is with so many 

 advantages and possessed of weapons effective against so many species 

 of animals, has some powerful antagonists. Were this not true the 

 world might have been depopulated by the unopposed activity of this 

 microscopic organism. As it is, it is possible that the extinction of 

 certain species of animals may have resulted from this infection. 

 Many other bacteria are markedly antagonistic and destructive to the 

 anthrax bacillus. Chief among those in which this function has been 

 observed and studied is the Bacillus pyocyaneus. In mixed cultures 

 of these organisms the pyocyaneus only survives. It not only survives 

 but it seems to feed on the anthrax bacilli. If across a gelatine plate 

 parallel lines be drawn alternatingly with needles moist with cultures 

 of the two bacilli, the pyocyaneus only will develop. If crosses be 

 made with the needles the pyocyaneus only will develop at the cross. 

 The pyocyaneus develops a bacteriolytic body known as pyocyanase, 

 which readily digests and destroys the anthrax bacillus. This seems to 

 be a proteolytic ferment, but unlike similar bodies it is not destroyed 

 by prolonged boiling. This fact has led to the suggestion that it 

 destroys the anthrax bacillus by osmotic changes. A few drops of a 

 solution of pyocyanase added to a bouillon culture of anthrax leads 

 to a speedy dissolution of the bacilli. Moreover, laboratory animals, 



