INTRODUCTION. 29

c

year Pasteur published a work upon Rouget dit Pore, and
Loffler and Schiitz reported the discovery of the bacillus
of glanders.

In 1884, Koch reported the discovery of the "comma
bacillus," the cause of cholera, and in the same year
Iv6ffler discovered the diphtheria bacillus, and Nicolaier
the tetanus bacillus.

In 1892, Canon and Pfeiffer discovered the bacillus of
influenza.

In 1892, Canon and Pielicke first found the bacillus
now thought to be specific for measles.

In 1894, Yersiu and Kitasato independently isolated
the bacillus causing the bubonic plague then prevalent
at Hong-Kong.

A new era in bacteriology, and probably the most
triumphant result of the modern scientific study of dis-
ease, was inaugurated in 1890 by Behring, who presented
to the world the u Blood-serum therapy," and showed as
the result of prolonged, elaborate, and profound study of
the subject of immunity that in the blood of animals
with acquired immunity to certain diseases (diphtheria
and tetanus) a substance was held in solution which was
potent to save the lives of other animals suffering from
the same diseases.