PATHOGENIC BACTERIA. PART I. GENERAL CONSIDERATIONS. INTRODUCTION. THE unrecognized inception of the department of science which we are about to study had its latent germs in the thought of antiquity. It is folly to begin the consideration of bacteria with their probable discoverer, Leeuwenhoek, or with the socalled "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 "in six days the Lord made heaven and earth, the sea and all that in them is," 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-an idea that would stamp him a disciple of Thales if we did not know that his doctrine was that "the Infinite is the substance of all things." Empedocles of Agrigentum (450 B. C.) attributed to spontaneous generation 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 |