516 THE BACILLUS OF SOFT SORE 



treat the preparation roughly otherwise the chains will be broken up. Dry, 

 fix and stain (vide ante). 



Sections. Fix small pieces of skin in acid perchloride, harden in alcohol 

 and embed in paraffin. Stain according to the method given above. 



(b) Cultures. Sow tubes of blood-agar with pus from the chancre or bubo, 

 using a liberal amount of material. To collect the material for sowing cul- 

 tures allow the pus to accumulate beneath a dry dressing, which should be 

 applied to the sore after disinfecting the latter with tincture of iodine. 



(c) Inoculations. Inoculation if made at all should be made on the man 

 infected with the chancre under investigation (p. 513). In this way the nature 

 of the sore may in some cases be determined, for if the inoculation " take," 

 the experiment indicates that the chancre is a soft sore. A positive result 

 does not however exclude the possibility of a co-existent syphilitic infection ; 

 and soft sores are often due to a mixed infection with the bacillus of soft 

 sore and the Treponema pallidum. 



