Licence: Public Domain Mark
Credit: The surgery of the head and neck / by Levi Cooper Lane. Source: Wellcome Collection.
Provider: This material has been provided by the Augustus C. Long Health Sciences Library at Columbia University and Columbia University Libraries/Information Services, through the Medical Heritage Library. The original may be consulted at the the Augustus C. Long Health Sciences Library at Columbia University and Columbia University.
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![tested by time, severe examination, skepticism and cool obser- vation. Immunity may naturally exist in man against disease com- mon to animals; and the converse is true of animals in respect to human disease. Artificial immunity may be acquired by man and animals, in several ways; it may be produced by inocu- lation with an attenuated virus, of which a familiar example is vaccine virus. Immunizing inoculation is done with a sterilized culture in which the toxic bacteria have been destroyed. And similar work has been done by the intravenous injection of highly attenuated virulent cultures. The serum of normal blood is antagonistic to bacteria; and when the latter are injected into the vessels of a living animal, the germs soon disappear; or rather, they become stranded in certain viscera, as the liver and spleen, where they die, disin- tegrate, and vanish. The power to destroy bacteria is, according to certain author- ities, possessed by white blood-cells, connective-tissue cells, mucous cells, endothetial cells, and glandular cells. This doctrine was announced by MetschnikofF, and has been accepted by a number of pathologists, and strongly op])Osed by others. MetschnikofF taught that when bacteria are admitted into the living body, there soon ensues a struggle between them and the bodily cells before mentioned; and that the victory is to the stronger party. The leading defendants of the body are the leucocytes, which receive into their interior the microbic entities and destroy them, the process being similar to that which occurs when a larger animal swallows and ends the life of a smaller one. If, on the contrary, the bacteria be superior in force and energy, the victory is theirs. This hostile action between living cells and bacteria is named phagocytosis; and the devouring cells are named pliagocyie.s. From the writer's study of this matter he infers that the living cells have had their day of phagocytic victories, and that this honor will hereafter belong rather to the serum than to the cells of the blood. Since the announcement by Davaine and Koch of the discov- eries which they liave made in the field of bacteria, a multitude of investigators have entered it and brought to light a great number of microbic agents. A part of these do not interest us, since they have no morbific action on man and animals; another portion, however, do concern both the physician and the surgeon, since they have been demonstrated to be the causal agents of disease in man. Morbific bacteria are named pathogenic organ- isms. An enumeration and brief notice of the leading patho- genic bacteria will herewith follow:—](https://iiif.wellcomecollection.org/image/b21215406_0025.jp2/full/800%2C/0/default.jpg)
