A small crystal of salt is irritating to the eye, but a much greater amount of the same substance in dilute solution causes no irritation.

The poisonous substances produced by bacteria are diluted and washed away from the part by the exudate.

Not only is there a greater amount of tissue fluid in the inflamed part, but the circulation of this is also increased, as is shown by comparing the outflow in the lymphatic vessels with the normal.

The fluid exudate which has come from the blood and differs but slightly from the blood fluid exerts not only the purely physical action of removing and diluting injurious substances, but in many cases has a remarkable power, exercised particularly on bacterial poisons, of neutralizing poisons or so changing their character that they cease to be injurious.
We have learned, chiefly from the work of Metschnikoff, that those white corpuscles or leucocytes which migrate from the vessels in the greatest numbers have marked phagocytic properties, that is, they can devour other living things and thus destroy them just as do the amoebae.

In inflammations produced by bacteria there is a very active migration of these cells from the vessels; they accumulate in the tissue and devour the bacteria.