Am,  Jour  Pharui.  | 
Oct.,  1885,  J 
Alkaloids  of  Coca  Leaves. 
467 
The  alkaloid  obtained  from  leaves  tliat  have  deteriorated  is  always 
TQore  or  less  dark  colored,  and  contains  a  small  proportion  only  that  is 
capable  of  taking  on  the  crystalline  form.  From  good  leaves  the 
alkaloid  obtained  in  assays  is  nearly  or  quite  colorless,  and  is  left  in 
the  form  of  a  crystalline  mass  on  evaporation  at  a  low  temperature  of 
the  ether. 
Crude  cocaine  has  a  characteristic  tobacco-like  odor,  which  suggests 
the  idea  that  some  portions  of  the  product  have  become  split  up  so  as 
to  reveal  the  pyridine  constituent  of  the  base.  This  odor,  however, 
•does  not  disappear  when  the  alkaloid  is  neutralized.  Solutions  of  the 
•crude  product  in  alcohol  have  generally  a  brownish  color,  which  is 
deep  in  proportion  to  the  amount  of  impurity  present.  From  hot 
alcoholic  solutions,  1 : 1,  a  large  portion  of  the  alkaloid  separates  on 
pooling  in  the  form  of  distinct  prismatic  crystals.  The  mother-liquor 
by  spontaneous  evaporation  yiekls  another  crop  of  less  perfect  crystals, 
which  may,  however,  be  obtained  by  repeated  recrystallization  nearly 
or  quite  colorless.  After  the  cocaine  has  all  crystallized  out  there 
remains  a  dark-colored  syrupy  liquid,  which  consists  partly  of  alka- 
loid apparently  identical  in  chemical  and  physiological  characters  with 
'Cocaine,  but  which  does  not  itself  crystallize,  and  does  not  form  crys- 
tallizable  salts.  For  this  uncrystallizable  alkaloid  the  names  cocaicine 
and  cocainoidine  have  been  proposed.  It  appears  to  bear  to  cocaine  a 
relation  similar  to  that  of  chinoidin  to  quinine,  or  of  invert  sugar  to 
sucrose,  but  no  ultimate  analysis  has  as  yet  been  made  of  it,  and  our 
knowledge  of  it  is  very  incomplete. 
Besides  this  there  is  often  present  a  feebly  basic,  extremely  bitter 
substance,  which  possibly  may  be  ecgonine,  of  which  accounts  acces- 
sible to  me  are  very  meagre.  The  malodorous  constituent  already 
mentioned  seems  not  to  have  the  character  of  an  alkaloid,  for  its  odor 
remains  unchanged  after  neutralization  with  an  acid.  It  is  easily 
separated  from  the  crystallizable  alkaloid  by  repeated  crystallizations, 
and  this  appears  to  be  the  only  way  of  obtaining  a  pure  product. 
Pure  cocaine  should  exhibit  the  following  characters :  colorless  dis- 
tinct crystals  (Fig.  1),  or  a  crystalline  white  powder,  without  odor,  at 
first  seeming  to  be  tasteless,  but  as  it  dissolves  developing  a  slightly 
bitter  taste,  and  producing  numbness  of  the  tongue ;  wholly  soluble 
in  ether,  soluble  also  in  alcohol,  chloroform,  benzol,  petroleum  ether, 
bisulphide  of  carbon,  in     petrolina     oil  and  melted  petrolatum,  and 
