Aocfo°berSym"}       The  Alkaloids  of  Ipecacuanha.  529 
tion  of  emetine  or  of  cephaeline.  With  that  object  the  following 
experiments  were  made  with  the  pure  alkaloids  : 
A  solution  of  -0968  gramme  emetine  in  53  minims  strong  hydro- 
chloric acid,  diluted  with  two  fluid  ounces  of  water,  was  evaporated, 
and  the  dry  residue  heated  for  sixteen  hours  upon  a  water  bath. 
At  the  end  of  that  time  the  residue  was  but  very  slightly  colored, 
and  was  found  to  contain -095 12  gramme  of  alkaloid,  a  difference 
from  the  quantity  taken  not  greater  than  may  be  ascribed  to  exper- 
imental error. 
In  a  similar  experiment  with  -09504  gramme  cephaeline  a  like 
result  was  obtained,  the  quantity  of  alkaloid  found  in  the  residue 
after  evaporation  being  -09328  gramme. 
The  effect  of  long-continued  boiling  (sixteen  hours)  of  solutions 
of  emetine  and  cephaeline  containing  excess  of  acetic  acid  was  then 
tried.  In  both  instances  there  was  but  little  alteration  in  the  color 
of  the  solutions,  and  the  quantity  of  alkaloid  afterwards  extracted 
was  almost  the  same  as  that  originally  taken  for  the  treatment. 
Under  both  of  these  conditions  there  appears  to  be  very  little 
alteration  of  either  emetine  or  cephaeline.  The  result  is,  however, 
very  different  when  solutions  of  either  of  these  alkaloids  in  acetic 
acid  are  evaporated,  and  the  dry  residue  is  heated  for  some  length 
of  time.  In  that  case  the  solution  becomes  colored  as  the  evapora- 
tion advances,  and  the  dry  residue  has  a  dark  brown  color,  which  is 
more  marked  with  cephaeline.  The  residues  left  on  evaporating 
acetic  solutions  of  the  alkaloids  have  an  alkaline  reaction,  from 
which  it  would  appear  that  the  acetates  are  decomposed  by  heating, 
and  that  the  alteration  of  the  alkaloids  is  due  to  the  action  of  heat 
upon  them  in  the  free  state.  An  experiment  made  to  ascertain  this 
point,  by  heating  cephaeline  moistened  with  water  in  an  open  basin, 
and  keeping  the  dry  residue  hot  on  a  water  bath  for  sixteen  hours, 
showed  that,  under  these  conditions)  there  was  a  loss  of  alkaloid 
amounting  to  17-6  per  cent.,  with  considerable  darkening.  On  dis- 
solving the  residue  in  hydrochloric  acid,  adding  ammonia,  and  shak- 
ing out  with  ether,  only  a  few  crystals  were  obtained,  and  the  am- 
moniacal  liquor  presented  a  marked  fluorescent  appearance. 
To  ascertain  more  exactly  the  extent  to  which  each  of  the  two 
different  alkaloids  of  ipecacuanha  is  altered  when  the  dry  residue  of 
an  acetic  solution  is  exposed  to  heat,  the  following  experiments 
were  made  : 
