Chapter XVI

HISTORICAL SKETCH OF OUR KNOWLEDGE OF IMMUNITY 505
Methods used by savage races for vaccination against snake venom
and against bovine pleuropneumonia.—Variolisation and
vaccination against small-pox.—Discovery of the attenuation of
viruses and of vaccinations with attenuated
micro-organisms.—Theory of the exhaustion of the medium as a
cause of acquired immunity.—Theory of substances which prevent
the multiplication of the micro-organisms in the refractory
body.—Local theory of immunity.—Theory of the adaptation of the
cells of the immunised organism.
Observations on the presence of micro-organisms in the white
corpuscles.—History of phagocytosis and of the theory of
phagocytes.—Numerous attacks upon this theory.—Theory of the
bactericidal property of the body fluids.—Theory of the
antitoxic power of the body fluids.—Extracellular destruction of
micro-organisms.—Analogy between bacteriolysis and
haemolysis.—Theory of side-chains.
Progress of the theory of phagocytes.—Attempts to reconcile it
with the humoral theory.—Present phase of the question of
immunity.