Germs must be pent up in the wound or abscess before they can set up a morbid process. Nature is not afraid of dust or germs or air. Dr. Tilden rightly says: "The whole question of wound infection hinges on drainage. Any wound that drains well may be smeared with the most virulent septic poison without infection. The infecting agent must be rubbed into the wound so that it will be pushed into, or below, the granular surface. The infecting material must find a lodgement so secure that the flushing--enzymic--serums cannot dissolve and wash away.

"Injuries in canals, tubes, ducts and air-passages will heal normally if drainage is not obstructed; but when obstructed, the usual conservative measures of nature may further obstruct, and death may result from a rational therapeutic measure mechanically obstructed in its execution."

Again: "The cell-building elements cover the cut or mutilated surface, and crowd the border so much that there is a heavy discharge through the drain, if the wound has been properly dressed or has been left open. Where drainage is unobstructed, the healing behind the barrage of nutritive material thrown out moves along without a halt. The proportion of enzymes and nutritive material furnished by a healthy, not overfed, wounded individual insures rapid renewal of tissue. If obstruction takes place, microbic fermentation is set up in the pent-up surplus. This is a conservative process; for it thins the discharge, irritates the wound, and causes an extra amount of serum to be exuded. The purpose is to melt down any incrustations and new-made tissue that is obstructing drainage."

Serious trouble may occur if this fails. Microbic fermentation gains the mastery over enzymic fermentation, sepsis is evolved and, unless walled off, may cause death.

If inflammation is due to a virulent irritant which is incompatible with the life and integrity of the tissues, these undergo retrograde changes, cloudy swelling, fatty degeneration, and complete necrosis, finally forming, in union with the decomposed serum, blood cells, etc., pus which breaks through on a nearby surface and runs out, or is walled off as in an abscess.

The irritation of an open wound caused by the air acts to accelerate the flow of nutritive material to the wound. The air dries up and coagulates the discharge of serum and thus it is sealed up so that healing can go on behind the protection. The dry covering "acts as a stay or fixation expediency, to secure the necessary quiet, for healing." If the wound is too closely sealed in and danger of infection threatens, itching sets in causing rubbing and scratching thus breaking enough of the covering to permit the washing out or escape of the pent-up pus and waste matter.

A wound that is not thoroughly cleansed and that is bandaged up so that drainage is imperfect, suppurates. Decomposition and infection end repair and cause sloughing. Sloughing re-establishes drainage and the work of healing is resumed. If sloughing does not occur so that drainage is not established and the normal reciprocal balance between the organized ferments (germs) and unorganized ferments (enzymes) is not established, sepsis is generated and this may end in death. One of the greatest modern surgeons, Sir Wm. Armuthnot Lane, of London, declared, that where drainage is perfect there is no death. As Dr. Tilden remarks:-"Every conservative provision of nature can be, and sometimes is, overcome; but this does not alter the fact that nature places a special guard over each one of the body's vital functions, the normal action of each being necessary to total health of the body, and that each guard must be vanquished before the function over which it presides can be deranged or checked."

If the surfaces of a wound are brought together and held there healing must be completed sooner than if nature must build up a bridge of tissue to span the gap. But bringing these edges together interferes more or less with drainage and, if means for drainage is not supplied, may result seriously. Again, healing is interfered with by the causes that lead to the inflammation. Inflammation is slight when the wound is in a state of health. Dr. Tilden says of the exudate in inflammation:-"There can be no rest or standing still; the exudates must be execreted, thrown out, or re-absorbed. To fit these exudates for absorption, they must be treated with enzymes, in order to fit them to re-enter the circulation. If there is enervation and lack of enzymes, then it will be 'up to' bacterial fermentation to prepare the exudate for expulsion from the body. If there is no break in continuity--if there is no open wound--then the bacterially treated exudate must be absorbed into the general circulation, causing infection; or the infection will be corralled by walling in the devitalized territory and lining the enclosure with an impervious pyrogenic membrane. The pus that forms is retained--not allowed to escape into the general circulation ; for, if it should, it would cause pyemia. If the body's natural resistance is too low to fortify it in this way--if it cannot localize and immunize the infecting material--then general infection takes place and the victim dies of septicemia."

It is not correct to limit the disposal of pus in a closed inflammation to absorption or abscess formation. The process of inflammation and supuration more often extends along lines of least resistance, through neighboring healthy tissue, until the abscess points at some surface. The pointing thins and liquifies by enzymic action the overlying tissue which finally ruptures allowing a spontaneous evacuation of the abscess to occur. Every one has seen this in boils or furuncules. However, in these liquification is only partial. The dead tissue sloughs en masse, as the "core" of the boil. Of internal exudates Dr. Tilden explains:-"If the point of irritation is the pleura, the exudate may accumulate, and, from lack of bacterial influence, the fluid is neither digested and absorbed, nor decomposed and converted into an abscess of the pleura, nor absorbed, creating septic fever and death; but remains a bland, innoxious fluid in the pleura."

A mere brief notice of a few examples of the work accomplished by inflammation must suffice at this place as other chapters of this work are replete with such examples. A sliver becomes imbedded in the flesh and is not removed. Inflammation sets up at this point. The tissues around it are liquified and formed into pus. The fester thus formed bursts and the pus runs out carrying the sliver along with it. The place is then healed and forgotten. By inflammation a bruise, as from a blow, a cut, a burn, etc., is repaired and healed. Any irritating substance, as mustard, Spanish fly (Cantharis), and other drugs, when applied to the surface of the body, or when taken internally are met and overcome by inflammation. Bites, bee stings, the bite of insects, snakes, and other poisonous animals, and the poisons of plants are all met and overcome by inflammation.