ME.  J.  LISTEE  ON  THE  EAELY  STAGES  OF  INFLAMMATION. 
665 
retardation  and  ultimate  stagnation.  Accordingly,  various  theories,  mechanical,  che- 
mical and  vital,  have  been  proposed  * to  explain  the  transition  from  “ determination  of 
blood,”  as  the  condition  of  dilatation  of  the  arteries  with  increased  flow  through  the 
capillaries  has  been  termed,  to  inflammatory  congestion,  as  the  accumulation  of  cor- 
puscles in  the  vessels  may  perhaps  be  most  fitly  designated.  But  the  second  simple 
experiment  with  mustard,  to  which  I would  again  direct  the  attention  of  the  reader, 
proves  in  a very  beautiful  manner  that  these  two  results  of  irritation  are  totally  distinct 
in  nature  and  independent  in  cause.  The  dilatation  of  the  arteries,  it  will  be  remem- 
bered, afiected  not  only  the  part  on  which  the  mustard  lay,  but  also  all  the  rest  of  the 
web,  showing  that  it  was  developed  indirectly  through  the  medium  of  the  nervous 
system ; whereas  the  accumulation  of  the  blood-corpuscles  in  the  vessels  below  the 
mustard  was,  as  we  have  seen,  the  result  of  the  duect  action  of  the  irritant  upon  the 
tissues.  The  arterial  dilatation  in  the  web  generally  led  to  no  changes  in  the  quahty 
of  the  blood,  which,  though  the  experiment  was  continued  for  some  hours,  retained  to 
the  last  its  natural  characters,  just  as  would  have  been  the  case  had  the  enlargement  of 
the  vessels  depended  on  an  operation  performed  upon  the  spinal  cord.  The  accumula- 
tion of  corpuscles,  on  the  other  hand,  implied  an  alteration  in  the  properties  of  the 
blood,  \iz.  an  abnormal  adhesiveness  in  the  red  discs.  Determination  of  blood  is  thus 
a pruely  functional  phenomenon,  and,  lihe  a blush  upon  the  cheek,  becomes  obliterated 
after  death  by  the  post-mortem  contractions  of  the  vessels : inflammatory  congestion,  on 
the  contrary,  is  the  first  evidence  of  organic  lesion,  and  declares  itself  as  distinctly  in 
the  dead  as  in  the  Imng,  being  the  most  important  if  not  the  only  sign  of  the  early 
stages  of  inflammation  discoverable  on  dissection  f,  as  for  instance  in  the  case  of  inci- 
pient meningitis  mentioned  in  the  Introduction  to  this  paper. 
Although  determination  of  blood,  as  met  with  in  the  frog,  is  thus  entirely  inde- 
pendent of  inflammatory  congestion,  yet  it  is  of  great  interest  with  reference  to  human 
inflammation.  Dilatation  of  the  arteries  is  now  generally  admitted  to  be  the  result  of 
the  relaxation  of  their  muscular  fibres;  and  that  it  is  a purely  passive  phenomenon, 
seems  to  be  absolutely  demonstrated  by  the  fact  which  I have  pointed  out  elsewhere 
that  after  the  vessels  have  been  liberated  from  the  control  of  the  nervous  system  by 
removal  of  the  spinal  cord,  they  dilate  fully  if  the  heart  continues  to  act  sufficiently 
* See  ‘Pathology  and  Practice  of  Medicine,’  by  W.  P.  Alison,  M.D.,  F.E.S.E. ; ‘Principles  of  Medicine,’ 
by  C.  J.  B.  Williams,  M.D.,  F.E.S.;  ‘Lectures  on  Surgical  Pathology,’  by  James  Paget,  F.E.S.;  ‘Essay 
on  the  state  of  the  Blood  and  the  Blood-vessels  in  Inflammation,’  by  T.  Wharton  Jones,  F.E.S.  ; ‘ Guy’s 
Hospital  Eeports,’  vol.  viii.;  ‘ Clinical  Lectures,’  by  J.  H.  Bennett,  M.D.,  F.E.S.E.;  also  Professor  Henle, 
as  quoted  by  Wharton  Jones,  op.  cit. 
t Since  the  reading  of  the  paper,  I have  pointed  out,  that  in  consequence  of  the  persistent  fluidity  of  the 
blood  which  continues  in  the  smaller  vessels  for  days  after  death,  the  red  corpuscles  have  time  to  gravitate 
into  dependent  parts,  and  thus  give  rise  to  that  appearance  oi post-mortem  congestion  which  more  or  less 
closely  simulates  to  the  naked  eye  what  would  have  resulted  from  inflammation  during  life.  See  a paper  by 
the  author  on  spontaneous  gangrene  from  arteritis,  and  the  causes  of  coagulation  of  the  blood  in  diseases 
of  the  blood-vessels,  Edinb.  Med.  Journal,  March  1858. 
J See  page  624  of  this  volume. 
4 S 2 
