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CONSTITUENTS  OF  COCA  LEAVES. 
be  perfectly  clear,  and  the  Magnesia  and  Citric  Acid  free  from 
all  insoluble  matter. 
I  hope  that  the  publication  of  this  formula  will  prove  of  ser- 
vice to  those  who  have  heretofore  been  disappointed  in  the  pre- 
paration of  this  article. 
Very  respectfully, 
William  J.  Watson. 
Brooklyn,  N.  Y.,  Feb.  18,  1861. 
ON  THE   ALKALOID  AND  OTHER  CONSTITUENTS  OP  COCA 
LEAVES. 
By  Dr.  Albert  Niemann,  of  Goslar. 
The  inaugural  dissertation  of  the  author  is  published  in  Witt- 
stein's  Y.  Schrift.  ix.  489-524 ;  it  contains  many  interesting 
facts,  but  is  too  lengthy  for  translation  ;  we  therefore  give  in  the 
following  a  condensed  account  of  it. 
After  discussing  the  importance  of  the  vegetable  alkaloids  in 
a  medicinal  point  of  view,  and  for  the  examination  of  crude 
drugs,  the  author  disapproves  of  such  incomplete  investigations 
as  enrich  our  knowledge  with  nothing  else  but  names,  and 
then  considers  the  interest  attached  to  those  stimulating  vegeta- 
bles, denominated  by  vou  Bibra,  narcotic  victuals,"  like  coffee, 
tea,  cacao  and  tobacco  ;  the  coca  leaves  are  employed  for  similar 
purposes  by  the  natives  of  Peru  and  Bolivia. 
The  Austrian  frigate  Novara  brought  from  Lima  a  quantity  of 
good  coca  leaves,  which  Professor  Woehler  handed  to  the  author 
for  investigation. 
After  treatinoj  at  leno-th  of  the  botanical  characteristics  of  the 
order  Erythroxylaceae,  which  comprises  only  the  genus  Ery- 
throxylon,  and  its  geographical  extension,  he  gives  a  minute 
description  of  E.  coca,  its  culture  and  the  use  and  properties  of 
its  leaves,  referring  to  the  observations  and  opinions  of  von  Mar- 
tins, Poeppig,  von  Tschudi,  Weddell  and  Scherzer,  some  of 
whom  have  advocated  the  introduction  of  the  coca  into  the  Eu- 
ropean navies  and  armies  on  account  of  its  well  known  qual- 
ities to  preserve  life  and  strength  for  a  considerable  time  with- 
out food. 
The  author  reviews  the  various  incomplete  investigations  of 
