The recent appearance of epidemic cholera in some parts of Europe has caused the publication, in various Continental medical journals, of many articles on the subject of acquired immunity to cholera as a result of protective inoculation of the ptomaine produced by the cholera vibrio. The subject is one of great interest in view of the high mortality of cholera, as well as the probability that this fall will not witness the extermination of the disease in Europe, and the spring of 1893 may, as has occurred in past epidemics, witness a renaissance of the present epidemic, that we are now informed is dying out.
In 1885 Dr. Jaime Ferran presented a paper to the French Academy of Sciences, in which he reported the results of experiments that showed that cultures of the cholera vibrio, injected subcutaneously in animals in suitable doses, produced certain local phenomena and rendered the animal