vegetable parasites to harm him. If, on the other hand, the tissues
have a low resistive power, because of general debility of the
patient, or of a local debility of the tissues themselves, and the
white cells be weak and not abundant, the bacteria will gain the
victory, get access to the general blood current, and invade every
portion of the organism. Thus, a general or a local disease will be
caused; varying with the species of bacteria with which the patient
has been affected, and the degree of resistance on the part of the
tissues.

From what has been stated it must be evident that the bacterial origin
of disease depends upon the presence of a disease-producing fungus and
a diminution of the normal healthy tissue resistance to bacterial
invasion. If there is no fungus present, the disease caused by such
fungus cannot develop. If the fungus be present and the normal or
healthy tissue resistance be undiminished, it is probable that disease
will not occur. As soon, however, as overwork, injury of a mechanical
kind, or any other cause diminishes the local or general resistance of
the tissues and individual, the bacteria get the upper hand, and are
liable to produce their malign effect.

Many conditions favor the bacterial attack. The patient's tissues may
have an inherited peculiarity, which renders it easy for the bacteria
to find a good soil for development; an old injury or inflammation may
render the tissues less resistant than usual; the point, at which
inoculation has occurred may have certain anatomical peculiarities
which make it a good place in which bacteria may multiply; the blood
may have undergone certain chemical changes which render it better
soil than usual for the rapid growth of these parasitic plants.