22 Cincinnati Society of Natural History. 



forms of blood-poisoning, by the application of antiseptic 

 precautions, having for basis the germ theory of disease. 

 Hospital statistics everywhere show this. This evidence 

 appeals to every family in the land, and requires no com- 

 plicated demonstration. 



We come to another stage in the development of these 

 studies. These micro-organisms do not simply act mechan- 

 ically. But in their living and dying, a very short period 

 often, there are elements produced which have, in numerous 

 instances, been proved to be very poisonous. This discovery 

 has brought workers more to the chemical, instead of the 

 biological, aspects of the subject. The.se products have been 

 called ptomaines, diastasis, etc., and are the direct agents in 

 the production of specific disea.ses. They have not been 

 isolated in all cases, even where we are .satisfied that germs or 

 microbes are directly the true cause concerned, but time will 

 most probably develop them. To antidote these deadly 

 poisons is now the object of very much laborious work. 

 These antidotes have been found and proven successful in a 

 nunijjer of instances, mostly in animal diseases, but not 

 al\va\s. The practice is in effect a vaccination, by which 

 aboliti(jn of a natural su.sceptibility to a disease is brought 

 al)<)ut. The process of preparation is vcr\- ilifficult and subtle, 

 and need not be explained here. We can, however, give 

 some results recently published h\ Dr. Arniand Ruffer, of 

 England. 



There is a disease of cattle called " 1)lack-quarter," which 

 attacks cattle. It has its bacillus and doubtless its " ptomaine " 

 (jr active principles of the disease. An attenuated form of 

 the virus is made and the animals are inoculated. In France 

 5,835 cattle were inoculated; mean mortality before was 

 10.84 per cent., and not infrequently it was 1 7 ])er cent. After 

 inoculation mortality fell at once to 2.15 per cent. In Switzer- 

 land, in 18S4, 2,190 animals were inoculated. Of these .22 

 l)er cent, died ; of the unvaccinated cattle 6.1 percent, died. 

 Much more evidence of same kind can l)e produced, as to the 

 di.sease. Of more direct interest tt) us is the record in regard 

 to inoculation for rabies or hydrophobia. Dr. Ruffer has 

 collected most of the statistics on the mortality of persons 

 bitten on any i)arl of the ])o(l\', and before \accination was 



