Elementary bacteriology and protozoölogy : the microbiological causes of the infectious diseases / by Herbert Fox.

  • Fox, Herbert, 1880-1942.
Date:
1913
Catalogue details

Licence: In copyright

Credit: Elementary bacteriology and protozoölogy : the microbiological causes of the infectious diseases / by Herbert Fox. Source: Wellcome Collection.

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    characteristics placing them without question among the plants, while others with equal definiteness belong to the animals. The line between is by no means sharp, and much difference of opinion exists among investigators as to the borderline forms. HISTORY The existence of more or less independent forms of life invisible to the naked eye was first proven about two and one-half centuries ago by Van Leeuwenhoek and Kircher, who actually saw and described what were called animalculse. The first conception of the existence of such microscopic forms cannot be accred- ited to these observers, since so long ago as in the fourth century b.c. Aristotle suggested the possibility. As might be expected, these single-celled bodies were not seen until the development of lens-making per- mitted accurate enlargement. The greatest advances have been made, furthermore, since the perfection of the compound microscope in the early years of the nineteenth century. It is also noteworthy that those who might be considered the founders of this science, so important to physicians, were botanists and chemists. The most important consideration for the early observers was the relation that these minute bodies bore to the spoiling of food and water. Indeed, most physicians of the past and not a few of the present have discredited the relation of bacteria to disease. The first opinion upon the relation of specific disease- producing bacteria came in the middle of the eighteenth century, but such a theory could not be proven until