METHODS OF HEALING. 481 



tlie surfaces "before separate are united. Out of tlie two layers 

 of granulations one is formed which pursues the normal develop- 

 ment of connective tissue. There are several circumstances in 

 which healing by secondary adhesion should be attempted ; for 

 example, in a wound presenting two separate surfaces, with a 

 gap between them, where pressure can be applied and the sur- 

 faces brought into immediate contact or apposition, by bandag- 

 ing or otherwise : this may be done in wounds of the legs, of 

 the lips, and of the flank. In this way wounds will heal up in 

 a very short time, whereas, if they are left to " fill up " with 

 granulations, the process will occupy a much longer period. In 

 applying means to produce this method of healing, certain con- 

 ditions are essential to success. 1st. That the granulations are 

 Ileal thy, not inflamed, profusely suppurating or degenerated, as 

 those in sinuses commonly are. 2d. The contact between them 

 should be firmly but gently maintained. 



HEALING UNDER A SCAB. 



This method of healing wounds is the natural one, and as 

 such requires no art. It is the method in which nearly all 

 wounds in animals, when not interfered with, heal. The scab 

 is formed of the fluids that ooze from their surfaces, dust and 

 other foreign bodies are entangled in this fluid, and under such 

 a scab the scar or cicatrix is securely formed. The edges of 

 this scab adhere over those of the wound, so as to form for it a 

 sort of air-tight covering, under which it heals without suppura- 

 tion, with the formation of a scar, which is more nearly like 

 the natural parts than any scar formed in a wound that remains 

 exposed to the air, and which does not, like it, contract so as 

 to produce deformity of the parts about it. The scab may be 

 formed of either dried blood, dried lymph and serum, or dried 

 purulent matter. 



The healing of a wound under a scab has always been consi- 

 dered a desirable process ; but to its universal adoption there is 

 some hindrance. For example, when the scab is once formed 

 and the wound covered, it is necessary that no morbid secretion 

 take place. Whenever, therefore, inflammation ensues in a wound 

 covered with a scab, the exuded fluid collecting under the scab 

 produces pain, compresses the wounded surface, or forces off the 

 2i 



