THE MICROBES OF HUMAN DISEASES. 211 



measles. A bacterium in the form of an 8 has also 

 been found in the urine of scarlet-fever patients. 



Stickler believes that he has discovered a vaccine 

 for scarlatina, by passing its virus through the horse 

 or the cow. When these animals are inoculated with 

 the blood of a man suffering from the disease, an 

 eruption accompanied by desquamation occurs three 

 days after inoculation. A man inoculated with this 

 desquamation displayed a rash resembling that of 

 scarlatina, and when the same man was afterwards 

 inoculated with human scarlatina, he did not take the 

 disease. 



Small-pox and Vaccinia. We find in small-pox 

 pustules micrococci, either isolated or united, which 

 may be seen on a section of the skin if they are 

 coloured with methyl violet. The same microbe may 

 be observed on the pustules of the mucous membrane 

 of the larynx, in the liver, the kidneys, and the blood 

 of the vena portae. The attempt to cultivate it has 

 hitherto failed. 



The micrococcus found in small-pox pustules does 

 not differ in its form from that of cow-pox in cows, 

 which constitutes, as we know, the original source 

 of human vaccine. It is not yet certain that the 

 microbes of small-pox and vaccinia are identical, but 

 from the resemblance of the pustules and of the micro- 

 cocci contained in them, it is most probable that this 

 is the case, and this would explain why vaccine is 

 efficacious as a preventive of small-pox. 



