Still,  what  Mr.  Hunter  said  is  true,  especially  in  wounds  in  our  own
bodies  :  subcutaneous  wounds  seldom  inflame  ;  open  wounds  generally
both  inflame  and  suppurate.  It  will  be  a  principal  object  of  this  lec-
ture to  show  something  like  an  anatomical  reason  for  this  difierence,  in
the  fact  that  the  materials  produced  for  the  repair  of  open  wounds  do
not  develope  themselves  quite  in  the  same  manner  as  those  for  the  repair
of  closed  or  subcutaneous  ones.  The  physiological  and  nearer  reason
is  to  be  discovered  in  the  influence  of  the  atmosphere  abnormally  ad-
mitted to  the  tissues,  and  producing  in  them  such  effects  as  are  more
nearly  traced  in  the  phenomena  of  inflammation.  For,  as  has  been  ar-
gued by  Mr.  Lister,'  the  organic  germs  which  Pasteur  and  others  have
shown  to  exist  floating  in  the  air,  excite,  when  in  contact  with  the
surface  of  a  wound,  decomposition  of  the  blood,  and  occasion  suppura-
tion.
Before  speaking  of  the  materials  for  repair,  I  must  briefly  state  that
the  healing  of  open  Wounds  may  be  accomplished  by  five  different
m^odes  :  namelyj  1.  By  immediate  union  ;  2.  By  primary  adhesion  ;  8.
By  granulation  ;  4.  By  secondary  adhesion,  or  the  union  of  granulations;
5.  By  healing  under  a  scab.^  The  repair  of  subcutaneous  wounds  may
be  effected  by  immediate  union,  but  is  generally  accomphshed  by  con-
nection, or  the  formation  of  bonds  of  union  between  the  divided  and
retracted  parts.  Very  rarely  it  is  effected  by  means  of  granulations
without  suppuration.
Of  these  modes,  which  I  hope  to  describe  hereafter  in  detail,  it  is
the  peculiarity  of  the  first,  or  process  of  immediate  union,  that  it  is  ac-

'  Lancet,  March  16,  1867.
