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TETANUS 



way of obtaining pure cultures of the bacillus. 

 Beginning with impure cultures such as Nicoiaier 

 had made, he kept these at a temperature of 

 36° C. till the bacillus had spored ; then, by repeated 

 exposures of the cultures to a temperature of 8o° C. 

 for three-quarters of an hour at a time, he killed-off 

 all organisms except the spores of the tetanus- 

 bacillus ; then he kept these in an atmosphere of 

 hydrogen, at a temperature of 20° C, and thus got 

 pure cultures. 



Brieger, Frankel, Cohen, Sidney Martin, 

 Kanthack, and others, have studied the chemical 

 products of the disease, have obtained them from 

 cultures and from infected tissues, and have been 

 able with these toxins to produce the disease in 

 animals. As with the other infective diseases, so 

 with tetanus, there have been two main lines of 

 researches ; the one, toward a fuller knowledge of 

 the chemical changes in the blood and in the central 

 nervous system ; the other, toward a fuller know- 

 ledge of the nature and ways of the bacillus, and 

 its method of invasion. Before any study of im- 

 munity or immunisation, or of neutralisation of the 

 toxins in man by an antitoxin, came the study of 

 the toxins and of the bacillus. It was proved, 

 by an immense quantity of hard work, that the 

 bacillus does not tend to invade the blood, or to 

 pass beyond the lymphatic glands in the immediate 

 neighbourhood of the site of inoculation ; that 

 it stays in and about the wound, and there multi- 

 plies, and from this site pours into the blood the 

 chemical products which cause the disease ; and 



