"  Quite  so.  They  are  in  a  state  of  extreme  con-
traction, far  exceeding  the  usual  *  rigor  mortis.'
Coupled  with  this  distortion  of  the  face,  this  Hippo-
cratio  smile,  or  '  risus  sardonicus,'  as  the  old  writers
called  it,  what  conclusion  would  it  suggest  to  your
mind?"

"Death  from  some  powerful  vegetable  alkaloid,"
I  answered  ;  "  some  strychnine-like  substance  which
would  produce  tetanus."

"  That  was  the  idea  which  occurred  to  me  the  in-
stant I  saw  the  drawn  muscles  of  the  face.  On  get-
ting into  the  room  I  at  once  looked  for  the  means


58  THE  SIGN  OF  THE  FOUR.  (

by  which  the  poison  had  entered  the  system.  As
you  saw,  I  discovered  a  thorn  which  had  been
driven  or  shot  with  no  great  force  into  the  scalp.
You  observe  that  the  part  struck  was  that  which
would  be  turned  toward  the  hole  in  the  ceiling  if
the  man  were  erect  in  his  chair.  Now  examine  this
thorn."

I  took  it  up  gingerly  and  held  it  in  the  light  of
the  lantern.  It  was  long,  sharp,  and  black,  with  a
glazed  look  near  the  point  as  though  some  gummy
substance  had  dried  upon  it.  The  blunt  end  had
been  trimmed  and  rounded  off  with  a  knife.
"  Is  that  an  English  thorn  ?  "  he  asked.
