618 
ME.  J.  LISTEE  ON  THE  PAETS  OF  THE  NEETOHS  SYSTEM 
G''  P.M.,  an  hour  and  a half  after  the  amputation,  the  vessel  still  maintained  the  same 
calibre,  but  at  7*^  35“  it  was  shghtly  less,  viz.  4°,  which  was  still  its  measurement  at 
11  o’clock.  Hitherto  no  change  distinctly  referable  to  -vital  contractility  had  taken 
place,  but  on  the  folio-wing  mornmg  the  vessel  was  reduced  to  3°  in  diameter,  and  on 
the  4th  of  April  it  was  of  different  sizes  in  different  parts,  -viz.  from  1^°  to  3°,  and  varied 
somewhat  during  the  course  of  the  day.  Still  more  striking  changes  in  the  diameter  of 
the  artery  appeared  on  subsequent  days ; thus  the  vessel  was  sometimes  constricted  to 
absolute  closure  in  one  part  of  its  com’se,  and  dilated  to  a very  considerable  degree, 
e.  g.  in,  another  part.  More  commonly,  however,  the  artery,  though  never  uniform 
in  size  as  in  health,  had  a general  tendency  either  to  moderate  constriction  or  dilatation. 
The  variations  occurred  frequently  during  the  twenty-four  hours,  and  on  one  occasion  I 
saw  the  artery  in  the  act  of  slow  contraction  at  one  part  driving  the  blood  into  a 
dilated  portion  at  a little  distance.  So  late  as  the  evening  of  the  10th  of  April,  i.  e. 
during  the  ninth  day  after  amputation,  far  later  than  vital  contractility  is  generally 
believed  to  last  in  a limb  so  circumstanced,  variations  of  calibre  continued  to  show  them- 
selves ; but  on  the  11th  of  April  the  vessel  had  an  almost  uniform  width  of  nearly  3°, 
and  exhibited  no  variations,  while,  at  the  same  time,  other  evidences  of  loss  of  vitality 
in  the  tissues  began  to  show  themselves.  The  accompanying  outlines  of  the  cahbre  of 
a limited  portion  of  the  artery,  which  was  the  subject  of  special  observation,  have  been 
made  from  micrometrical  measurements  selected  from  among  a large  number  daily 
registered.  They  will  serve  to  convey  an  idea  of  the  more  striking  vaiieties  of  appeai-- 
ance  presented  at  different  times.  It  may  be  mentioned,  that  the  diameter  of  the  vessel, 
when  most  dilated,  was  about  4^  times  the  length  of  a red  corpuscle  of  the  frog’s  blood. 
April  2. 
April  5. 
April  7. 
April  7. 
April  10. 
April  11. 
It  must  be  added,  that  the  limb  was  kept  wrapped  in  clean  wet  Imt  hi  a cool  place 
in  the  intervals  of  the  observations,  and  that  during  the  periods  of  examination  care  was 
