ON  ISOMERIC  ALKALOIDS. 
179 
dealing  with  isomers  instead  of  identical  bodies.  The  greatest 
differences  were  found  with  the  bases  produced  bj  destructive 
distillation  of  cinchonine.  Here  the  odor  of  the  alkaloids  was 
so  different  to  that  of  the  same  bodies  extracted  from  other 
sources  that  I  long  oscillated  between  two  opinions.  However, 
the  resemblances  were  too  numerous  to  justify  me  in  announcing 
the  pyridine  series,  as  obtained  from  cinchonine,  to  be  a  new 
class  of  alkaloids.  In  fact,  the  absence  of  absolutely  distinct 
reactions  rendered  such  a  course  impossible.  I  have,  however, 
at  length  discovered  a  reaction  with  the  chinoline  series  as  ob- 
tained from  cinchonine,  which  is  so  totally  different  from  any- 
thing which  can  be  obtained  with  the  chinoline  series  from  coal 
tar,  that  I  am  fully  persuaded  of  their  being  essentially  dif- 
ferent. 
Chinoline,  or  lepidine  from  cinchonine,  was  boiled  with  iodide 
of  amyle  for  a  few  minutes,  after  which  water  was  added,  and 
the  boiling  continued  for  a  short  time.  The  product  was  a 
brown  oily  looking  fluid  suspended  in  the  water.  A  little  am- 
monia was  now  poured  in,  and  the  boiling  continued  for  a  short 
time  longer,  when  the  whole  of  the  oil  became  converted  into  a 
magnificent  blue  color  of  the  utmost  intensity.  It  dissolves 
readily  in  alcohol,  and  the  diluted  fluid  dyes  silk  of  a  fast  and 
most  brilliant  blue,  having  a  slight  shade  of  purple. 
So  strong  is  the  attraction  of  silk  for  the  dye  that  the  bath 
becomes  colorless,  every  trace  of  color  being  taken  up.  It  has 
but  small  tendency  to  unite  with  cotton,  for  if  the  latter,  after 
being  dyed  blue,  be  boiled  with  silk,  the  cotton  becomes  color- 
less and  the  silk  absorbs  all  the  color. 
The  coal  tar  bases  of  the  same  composition  present  nothing 
similar.  They  may,  it  is  true,  be  made  to  yield  superb  color- 
ing matters,  but  by  totally  different  modes  of  procedure. 
I  am  at  present  endeavoring  to  ascertain  whether  the  pyri- 
dine series  from  cinchonine  possess  any  features  sufficiently  dis- 
tinct from  the  same  series  as  extracted  from  coal,  to  justify  the 
conclusion  of  their  being  a  distinct  class. — Chemical  News,  Dec. 
17, 1859. 
