Read and Demonstrated before the Section on Microscopy of the Brooklyn
Institute.
In presenting the subject of Bacteria, I wish to disclaim any
originality for the matter offered. I have endeavored to collect from
such sources of information as I have access to the important dates,
names and facts which have marked the progress of bacteriology up to the
present time.
So far as we know, the first observer of bacteria and the so-called
infusoria was Leeuwenhoek, who, with a simple magnifying glass, noticed
in a drop of putrid water the multitude of little granules moving about
in it. This was in 1675, and his observations were communicated to the
Royal Society of Sciences in the same year. In the following year he
recognized bacteria in the tartar from the teeth, and though he did not
name them, his description of their forms and his drawings enable us to
identify them as vibrios. There appears to have been no important
investigations carried on until nearly one hundred years later, or in
1773, when Müller, a Dane, attempted to classify the organisms then
known. He called them all infusoria, from the fact that they were the
product of infusions, and divided them into two genera—the monas and
vibrio. The monas he subdivided into ten forms and the vibrio into
thirty-five; but his descriptions of them are so faulty that it is at
present impossible to identify them from his writings. During the
following century the study of bacteriology attracted more or less
attention, and in 1829 Eherenberg, who is the Humboldt of the science,
commenced his investigations, which for fifty years he pursued with an
ardor and enthusiasm second to not even Darwin himself. He, in 1838,
classified the family of vibrioniens, and with the additions made by
Dujardin in 1841, placed them in a scientific category. Of course during
this period many were the disputes and discussions as to specie, genera
or family, each newly discovered member belonged to. And we have to come
to the period of Hallier, Hoffmann and Cohn, and many others, before the
questions, which had up to that time been in dispute, were settled.
Ehrenberg’s original classification was into: