66 ESSAYS ON BACTERIOLOGY. 



doubtful. We are not in position as yet to make ab- 

 solute statements in coiirt as to the diagnostic impor- 

 tance of the gonococcus, at least as found by tbe mi- 

 croscope alone. 



7. Smallpox and Vaccination. — ^Renewed interest 

 has been taken and renewed activity shown- in investi- 

 gating the question of the identity of variola and vac- 

 cinia. Unmistakably the tendency of experiments is 

 to confirm the view that vaccinia is nothing but vari- 

 ola modified by passing through the cow. This 

 might and would seem strange were it not for the fact 

 that the last ten years has shown that the virus of 

 many other diseases may be much modified by pas- 

 sage through the body of certain animals. It is quite 

 possible that we shall soon have established the fact 

 that variola is inoculable upon the cow, if the inocula- 

 tion is properly made — ^that such inoculation becomes 

 changed after efiicient repetition into vaccinia, and 

 that inoculation in this way affords an always con- 

 trollable means of obtaining animal vaccine. 



8. Bacillus Pyocyaneus. — The microbe of green 

 pus has risen into prominence and importance, chiefly 

 because of its remarkable influence in axresting the 

 development of anthrax when inoculated at about the 

 same time as that virulent germ. 



9. Malaria. — The diagnostic value of the malarial 

 Plasmodia remains high; indeed, the best opinion 

 tends to make it absolute. The work of Osier, Welsh, 

 and Councilman in this country, and of Laveran, 



