476 
Alkaloids  of  Coca  Leaves. 
A.m.  Jour.  Pharm. 
Oct.,  1885. 
salt.  The  limit  of  sensitiveness  with  different  reagents  was  also  in 
some  cases  strikingly  different,  although  we  must  remember  that  the 
solution  of  the  amorphous  product  is  itself  probably  complex  in  char- 
-acter. 
With  alkalies  the  limit  was  found  to  be  at  a  dihition  of  about 
1 : 1000,  with  platinum  chloride  1 : 1,200,  with  gold  chloride  1 : 9,000, 
with  picric  acid  1 : 5,000  (that  of  the  crystallizable  salt  being  only 
1 : 1,000),  with  Mayer's  reagent  1:18,000  (that  of  the  crystallizable 
salt  being  1:200,000). 
Solutions  prepared  from  the  amorphous  alkaloid,  if  evaporated  even 
at  a  very  gentle  heat,  have  invariably  turned  dark,  and  if  the  salt  is 
evaporated  quite  to  dryness  it  is  found  to  be  then  imperfectly  soluble 
in  water.  A  solution  of  the  crystallizable  salt  can  be  evaporated  even 
at  100°C.  without  changing  color,  and  the  residue  is  perfectly  soluble. 
It  is  probable,  however,  that  the  body  which  sutlers  decomposition  in 
evaporation  is  a  distinct  alkaloid  or  a  non-alkaloidal  substance,  for 
solutions  which  have  been  treated  with  animal  charcoal,  or  by  some 
other  plans  for  purification,  while  they  still  contain  amorphous  alka- 
loid in  abundance,  do  not  exhibit  this  behavior. 
One  peculiarity  of  even  the  purest  cocaine  salts  is  their  disposition 
to  give  up  their  acid,  probably  a  result  of  the  instability  of  the  base. 
Steel  spatulas,  etc.,  exposed  to  the  air  in  contact  with  the  dry  hydro- 
chlorate  soon  become  rusted,  but  the  same  thing  is  often  observed  in 
regard  to  the  salts  of  ammonia  and  other  volatile  bases. 
The  important  points  which  I  wish  to  emphasize  are:  1.  That  the 
alkaloid  obtained  from  coca  leaves  consists  of  a  mixture  of  several 
different  substances,  only  one  of  which  is  entitled  to  the  name  of 
cocaine.  2.  That  the  separation  of  normal  cocaine  from  its  accompa- 
nying alkaloids  can  only  be  effected  by  processes  of  crystallization, 
either  of  the  alkaloid  itself  or  of  some  of  its  salts. 
In  comiluding  I  desire  to  express  my  obligations  to  the  firm  of 
Parke  Davis  &  Co.  for  the  use  of  their  laboratory  facilities,  and  espe- 
'cially  for  the  material  aid  rendered  by  them  in  supplying  the  illustra- 
tions that  accompany  these  notes.  I  trust  that  some  one  more  bur- 
dened with  leisure  than  the  writer  will  be  found  to  pursue  lines  of 
inquiry  that  I  have  been  able  only  to  indicate,  and  that  our  knowledge 
of  the  alkaloids  of  erythroxylon  will  soon  be  as  full  and  exact  as  that 
of  the  cinchona  group. 
Detroit,  Mich.,  Aug.  24,  1885. 
