PATHOGENIC BACTERIA.

PART I. GENERAL CONSIDERATIONS.

INTRODUCTION.

IT is incorrect to begin the consideration of bacteriol-
ogy, as is so often done, with the probable discoverer of
bacteria, Leeuwenhoek, or with the so-called u Father of
bacteriology," Henle. The controversies and ideas which
stimulated the investigations and researches which have
brought us to our present state of knowledge were begun
hundreds of years before the beginning of the Christian era.

Excepting such as taught and believed that u in six
days the Lord made heaven and earth, the sea and all
that in them is,1' or a kindred theory of the origin of
things, the thinkers of antiquity never seem to have
doubted that under favorable conditions life, both animal
and vegetable, might arise spontaneously.

Among the early Greeks we find that Anaximander
(43d Olympiad, 610 B. c.) of Miletus held the theory that
animals were formed from moisture. Empedocles of
Agrigentum (450 B. c.) attributed to spontaneous genera-
tion all the living beings which he found peopling the
earth. Aristotle (B. c. 384) is not so general in his view
of the subject, but asserts that ^sometimes animals are
formed in putrefying soil, sometimes in plants, and some-
times in the fluids of other animals".5' He also formulated
a principle that u every dry substance which becomes
moist, and every moist body which becomes dried, pro-
duces living creatures, provided it is fit to nourish them.'*

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