« 
408  The  Ptomaines.  {^au^IiYmssT' 
raised,  as  made  upon  the  latter  point  with  regard  to  veratrine.  Hap- 
piljj  and  this  is  a  point  upon  which  we  have  ah-eady  insisted,  the 
production  of  the  ptomaines,  although  commencing  a  very  short  time 
after  death,  does  not  attain  to  but  a  very  small  quantity,  which,  if  in 
most  cases  sufficient  to  admit  of  its  characterization,  is  not  capable 
of  influencing  the  special  reactions  of  the  vegetable  poison,  except 
within  very  restricted  limits. 
There  is,  however,  a  case  where  an  error  will  be  more  difficult  to- 
avoid,  at  least  from  a  theoretical  point  of  view :  it  is  that  when  besides- 
a  certain  quantity  of  a  ptomaine  only  traces  of  an  alkaloid  are  found, 
which  was  the  cause  of  death ;  the  case,  for  example,  of  poisoning  by 
a  minimum  dose  of  strychnine,  and  that  the  toxicological  research  is 
made  several  months  afterward.  Under  these  conditions  the  develop- 
ment of  the  ptomaines  will  be  advanced,  and  if  it  be  true  that  the 
strychnine  gradually  disappears  in  the  tissues  of  the  poisoned  animals, 
which,  moreover,  with  Dragendorff,  we  place  in  doubt,  one  conceives 
that  tlie  characters  of  the  trace  of  isolated  strychnine  may  be  completely 
concealed  by  those  of  the  predominating  ptomaine,  and  notably  the 
blue-violet  coloration  which  it  gives  with  potassium  bichromate  and 
sulphuric  acid,  a  coloration  which  quickly  disappears,  concealed  by  the 
brown  and  then  green  coloration  which  is  produced  under  ti  e  same 
conditions  by  the  ptomaine  and  the  impurities  which  are  ahvays  mixed 
with  the  isolated  toxic  substance. 
But  the  situation  will  no  longer  be  the  same  if  the  expert  examina- 
tion is  made  a  short  time  after  death ;  and  under  these  conditions  on 
the  one  hand  the  development  of  the  cadaver  alkaloids  will  be  but 
slightly  advanced,  and  on  the  other  the  poison  sought  for  will  not  have 
become  subjected  to  alteration.  If  one  thus  arrives  at  the  isolation  of 
a  certain  proportion  of  crystallizable  alkaloid  in  the  free  state,  and 
presenting  a  perfect  accordance  in  physical,  chemical  and  physiological 
properties  with  a  vegetable  poison,  one  will  have  the  right  to  conclude 
as  to  the  presence  of  the  alkaloid  which  presents  these  properties^ 
especially  if  one  recalls  the  fact  that,  notwithstanding  the  assertion 
of  a  certain  advocate,  the  physiological  reaction  accompanied  by  a, 
miographic  study  is  decisive,  and  that  the  persistence  of  sensitiveness 
of  the  muscle  to  the  induction  current  is  a  reaction  foreign  to  the 
ptomaines. 
From  that  which  precedes  it  results  that,  if  in  certain  cases  the 
difficulties  of  the  expert  examination  may  be  great,  they  are  not  insure 
