74 INFLAMMATION. 



Hair is never regenerated : bnt so long as the skin con- 

 tinues whole, and if the bulbs (which are lodged below the 

 substance of the skin) remain uninjured, it grows again : 

 indeed, so long as this is the case, hairs will be produced 

 though they should be plucked out. Where a scar has formed, 

 and w^here the injury is such as to destroy the bulbs, no hair 

 will ever grow over the place. When we perceive weak, 

 scattered grey hairs growing over the spot, we may conclude 

 that the bulbs have not altogether been deprived of their 

 organization, or have been drawn away from the adjacent 

 skin. Attention to these circumstances will enable us to 

 answer the question so frequently put in cases of hrolien 

 knees : — '' Will there be any scar or mark left?-" 



Interstitial Depo^ion will comprehend adhesion^ in- 

 duration, scirrhus, hepatization^ ossification, softening, and, 

 in fact, all changes of structure. 



Adhesion. — Having completed the description of the 

 process of granulation, and seen how the wounded part is 

 ultimately closed, I shall now return to the open wound, 

 and point out the other modes of healing which the consti- 

 tution possesses : I mean cfirect union of the divided surfaces 

 by a process called adhesion. Whenever a clean cut wound 

 is made through the skin, the sides of the wound being 

 shortly afterwards brought together and maintained in appo- 

 sition, we have reason to expect union of the divided parts, 

 or that the wound in this summary manner will be healed 

 up and cured. Mr. Hunter called this unio7i by the first 

 inte7iiion ; in contradistinction to the process of granulation, 

 which he designated union by the second intention; and he 

 imagined that the blood (effused in consequence of the divi- 

 sion of its vessels) formed the bond or medium of union.- — 

 ''The blood being alive,'^ said he, ''becomes immediately 

 part of ourselves, and, the parts not being offended by it, 

 no irritation is produced. The red particles are absorbed, 

 and nothing but coagulating lymph is retained, which being 

 the true living bond of union, afterwards becomes vascular, 

 nervous, &c." Subsequent observation, however, has shown 

 this conjecture to be erroneous. It is now well known that 



