AmjJ°nue^1f0h2armi}     Recent  Literature  Relating  to  Pharmacy.  301 
'*  A  decoction  of  coffee  was  prepared  by  boiling  for  forty-five 
minutes  ground,  roasted  coffee  with  ten  parts  of  water,  replacing 
from  time  to  time  the  liquid  lost  by  evaporation,  filtering  whilst  hot . 
and  percolating  through  the  marc  and  filter  enough  hot  water  to 
make  ten  parts.  A  decoction  of  black  '  English  Breakfast '  tea 
was  made  in  a  precisely  similar  manner.  Both  liquids  were  some- 
what acid  to  litmus.  The  coffee  became  somewhat  turbid  on  cool- 
ing. The  tea  showed  a  very  pronounced  diffuse  precipitate,  and 
became  almost  opaque  in  thick  layers.  This  could  not  be  removed 
by  filtration  through  paper.  It  could  be  made  to  disappear  by 
heating  or  by  the  addition  of  alcohol.  On  account  of  this  turbidity 
the  reactions  were  always  compared  with  corresponding  dilutions  of 
the  decoctions  with  water.  Neither  decoction  gave  any  precipitate 
with  dilute  hydrochloric  acid,  nor  with  Mayer's  reagent,  in  the  pro- 
portions which  were  used.  The  tests  were  made  by  adding  definite 
proportions  of  the  decoctions  to  solutions  of  the  substances  to  be 
investigated,  and  noting  the  resulting  phenomena  at  once,  and  after 
standing.  If  a  turbidity  or  precipitate  occurred,  a  portion  of  the 
unfiltered  liquid,  in  the  case  of  alkaloids,  was  mixed  with  about 
one- fifth  volume  of  5  per  cent,  hydrochloric  acid,  and  with  one 
volume  of  alcohol,  to  test  the  solubility.  Another  portion  of  the 
liquid  was  filtered,  and  a  part  of  the  filtrate  was  put  with  more  of 
the  decoction.  If  no  further  precipitate  occurred,  a  few  drops  of 
Mayer's  reagent  were  added.  In  the  case  of  metallic  salts  the 
decoction  was  added  until  a  further  portion  ceased  to  affect  the  fil- 
trate, and  the  latter  was  then  tested  for  the  metals.  The  propor- 
tions usually  employed  for  the  alkaloids  were  2  c.c.  of  1  :  100 
aqueous  solution  of  the  alkaloid1  to  I  c.c.  of  the  decoction  (expressed 
in  the  table  as  1:150 — 3  ^  per  cent.)  or  5  c.c.  each  of  1  :  icoo 
solution  of  alkaloid,  and  of  the  decoction  (expressed  as  1  :  2000 — 
5  per  cent.)." 
Details  of  the  experiments  are  then  given  in  extenso,  after 
which  the  conclusions  are  stated  as  follows  : 
I. — Precipitation  of  Alkaloids. — Atropine,  coniine,  morphine  and 
pyridine  are  not  precipitated  even  in  fairly  strong  solution  by  coffee, 
Tea  precipitates  them  from  strong,  but  not  from  weak,  solutions. 
1  Or  one  of  its  salts,  brought  into  solution  if  necessary  by  the  addition  of  a 
few  drops  of  5  per  cent.  H2S04. 
