The white blood corpuscles are seen in the exudate in greater abundance than under normal circumstances. These cells are credited with wonderful powers of destroying germs, particles of dead matter, etc. Some of these are credited with great germ killing powers and have been named phagocytes. Others that are said to have but little phagocytic powers, and called by Metchnikoff, moerophages, are said to be chiefly responsible for the removal of non-bacterial substances. They are said to often contain dead cells and fragments of cells. Granules of pigment which get into the tissues when a hemorrhage into the tissues occurs, are said to be removed by this class of cells. They are described as often joining together, thus forming connected masses around a hair, or around a thread placed in a wound by a surgeon, in their efforts to remove these. They are also credited with power to destroy living cells when these are too great in number in some part, and thus they tend to restore cell equilibrium.

This view of the nature and function of the white blood corpuscles is rejected by many. The late Dr. Thomas Powell contended that these are not true cells but that they represent decaying particles of protein matter. He claimed that their increase was the cause of "disease" and not a means of overcoming "disease." He gave them the name pathogen--"disease" producer.

This view was accepted by the late Dr. Henry Lindlahr and many others. The future will have to decide which view is correct. The view that their increase is the cause of "disease" is not illogical. The view that their increase is a means of defense is not out of harmony with what we know of the body. It is a definite property of all living organisms that repair occurs following injury and most of the changes that take place in the work of repair are merely modifications and accentuations of the ordinary processes of normal life.

We have our point of injury now to a point of almost feverish activity. There is an excess of fluid pouring into it. The cells are dilated and multiplying. Blood vessels are also dilated and, perhaps, multiplied. The cells in the injured part are actively engaged in repairing damages. This feverish activity continues until the injury is repaired, or so long as the cause producing the injury operates, after which it gradually returns to normal. Then a reverse process begins.

The excess of fluid is removed by increasing the outflow until this exceeds the inflow. The excess of cells is removed. Part of them are removed with the fluid. Others undergo solution while others are claimed to be devoured by the other cells, particularly, by the white corpuscles. The blood vessels return to their normal size, the newly formed vessels atrophy and disappear in the same manner as the excess cells. The exudate is absorbed, the swelling goes down, pain ceases, the color becomes normal and function returns to its normal standard.

When the changes which an injured part undergoes are closely analyzed they are seen to be purposeful. They all serve definite ends and these are all beneficient. They are each and every one, without exception, designed to restore the integrity of the living organism and protect it from further injury. What has happened? A broken bone has been repaired; or a cut has been healed; or a foreign body has been removed from the flesh; or toxins have been diluted, altered and cast out; the threatened danger to the life of the organism or its part has been overcome. This is the work of inflammation. Truly, as Jennings said, there is "order in disorder"' in the workings of nature even in the most violent stages of "disease." He remarked of a case of inflammation: "This is not a freak of nature. She does not wantonly turn aside from the natural and habitual course of action, and throw her complex machinery into disorder, and give it suicidal motion and tendency. There was an imperative necessity for just the series of developments in this case that have been and yet are to be made."--Philosophy of Human Life, pp. 162-163.

Tissues which have been killed by mechanical, thermal or electrical injury or by toxins, etc., are no longer parts of the body. They are foreign substances and act as such. They act like foreign bodies thrust into the tissues from without. They occasion inflammation in their neighborhood. The fact that they once belonged to the body makes no difference to the tissues they affect. In such cases there is, in addition to the ordinary phenomena of a simple inflammation, processes the object of which is the removal of the foreign substance.

If a foreign substance is soluble or destructible these are attacked and dissolved and carried out of the system. If the substance is not soluble as, for instance, necrosed bone, compact hemorrhagic patches, infarcts, coagulated or condensed exudations, necrotic cheesy masses, leaden bullets, ivory pegs, ligatures, drainage tubes, etc., the process is a bit different. Inflammation and infiltration are followed by the formation of granulation tissue and later fibrous tissue around the foreign body. If it cannot be absorbed or sent out by suppuration, it becomes encapsulated.

Pieces of dead flesh and bone are sure, sooner or later, to be dissolved and carried away. In every case the process of absorption and encapsulation is carried out with the purpose of either ridding the body of a substance that is foreign and useless to it and, perhaps, also harmful; or of encasing it and rendering it harmless. Every movement of the body in the highest stages of health and in the lowest depths of "disease" is intended to preserve the vital integrity.

In simple cases of inflammation, where there is no breaking down of tissue, the exudate is absorbed and the tissue is left apparently as it was, with, perhaps, a deposit of pigment or a slight growth of new connective tissue or a thickening of the skin. Where there has been tissue destruction and its removal, as in an abscess, the gap is filled with granulation tissue. The surplus exudate in such cases is discharged as pus. A little more detail about suppurative and septic inflammatory processes is desirable.

Dr. Walter brought to our attention, in a former quotation, that inflammation does not proceed to a destructive stage unless foul matter has obtained entrance into the inflamed section either from without or from the blood. Dr. Tilden explained that in cases of foulness of the system nature utilizes the wound or suppurating process as a "portal of exit" or, to use the words of Dr. Lindlahr, "discharges and ulcers act as fontanels to the system." That this is so is unintentionally corroborated by orthodox testimony. (See chapter on "Crises")

The repair of injury requires extra nutrition. Nature sends great quantities of this to the injured section. In a wound, the exposed surface is sealed up by the coagulation of the exudate and healing proceeds. But where the waste is retained, that is where drainage is not perfect, microbic fermentation, as distinguished from enzymic fermentation, occurs. This changes the chemistry of the exudate and decomposition or pus formation supplants healing.