AD4imb«jSt '}    On  Some  of  the  Tests  for  Quinine.  563 
the  washed  gas.  This  solution,  for  uniformity  of  results,  should  be 
freshly  prepared  and  preserved  from  the  action  of  light.  When  this 
reagent  was  used  in  the  form  of  drops,  these  were  delivered  from  a 
pipette  delivering  on  an  average  twenty-five  drops  per  cubic  centi- 
metre.   The  ammonia  employed  had  a  density  of  950. 
A.    I-IOOth  solution  of  quinine, 
1.  5  c.c.  of  this  solution  (=  50  mgms.  quinine)  yields  with: 
(a)  o-i  c.c.  of  chlorine  water:  a  colorless  solution  which, 
on  the  addition  of  a  drop  of  ammonia,  yields  a  copious 
white  precipitate  (of  quinine),  and  after  a  little  time,  the 
mixture  acquires  a  rose-red  color ;  on  the  addition  of  a 
second  drop  of  ammonia,  the  mixture  becomes  colorless, 
then  slowly  assumes  a  greenish  hue  which  becomes  well, 
marked. 
(b)  0  5  c.c.  of  chlorine  water,  followed  by  a  drop  of 
ammonia,  yields  a  copious  white  precipitate,  and  the  mix- 
ture quickly  assumes  a  green  color,  then  becomes  dark 
rose-red  and  finally  green. 
(c)  10  c.c.  chlorine  water  and  a  drop  of  ammonia:  an 
immediate  green  color,  which  quickly  changes  to  dark  red, 
then  to  purple  or  blue. 
2.  1  c.c.  of  a  i-iooth  solution  (=  10  mgms.  quinine)  yields  with: 
(a)  One  drop  chlorine  water  and  then  a  drop  of 
ammonia :  a  copious  white  precipitate,  which  quickly 
assumes  a  green  color. 
(b)  0  5  c.c.  chlorine  water  and  a  drop  of  ammonia:  an 
intense  green  coloration. 
(c)  10  c.c.  chlorine  water  and  one  drop  of  ammonia: 
a  bright  green  coloration,  which  becomes  darker  in  color 
and  finally  nearly  black. 
3.  01  c.c.  of  a  i-iooth  solution  (=  1  mgm.  quinine)  in  a  very 
small,  narrow  test  tube,  yields  with : 
(a)  One  drop  of  chlorine  water  and  a  drop  of  ammonia: 
a  copious  green  precipitate. 
{b)  Two  drops  chlorine  water  and  a  drop  of  ammonia : 
a  bright  green  coloration. 
(r)  Three  drops  chlorine  water  and  a  drop  of  ammonia : 
no  precipitate,  but  the  mixture  immediately  acquires  a 
bright  green  color,  which  quickly  darkens. 
