AM,  Jour  Pharm.  ) 
.Mar.  1, 1873.  j 
Gaffeina  in  Coffee,  etc. 
121 
Nation.  The  fruit  gets  soft,  it  becomes  wet  through  continually,  and, 
af  distilled,  pure  alcohol  is  obtained  and  carbonic  acid  becomes  free. 
Pasteur  repeatedly  recurs  to  these  facts,  for  they  are  the  basis  of 
m  discovery  of  endless  importance,  and  are  of  greater  weight  because 
they  will  form  the  connecting  link  between  theories  at  present  opposed 
to  each  other. 
At  the  first  glance  we  might  suppose  that  this  second  discovery  was 
a  contradiction  of  the  first,  and  that  the  views  of  Liebig  and  Fremy — 
that  ferment  germs  and  fermentation  itself  develop  spontaneously  in 
•organisms  of  themselves,  without  any  action  from  without — were  cor- 
rect ;  but  Pasteur  insists  that  he  will  soon  complete  his  observations 
and  make  all  clear. — Journ.  Applied  Chem.,  Feb.,  187-3. 
THE  AMOUNT  OF  GAFFEINA  CONTAINED  IN  COFFEE,  AND  ON 
ITS  PHYSIOLOGICAL  ACTION. 
By  Hermann  Aubert. 
Although  the  quantity  of  caffeina  contained  in  raw  coffee  is  known, 
«k>  attempt  has  ever  been  made  to  ascertain  how  much  of  the  alka- 
loid is  contained  in  a  cup  of  coffee,  and  it  is  also  uncertain  whether 
the  beans  should  be  slightly  or  strongly  roasted,  and  whether  the 
ground  coffee  must  be  boiled  to  extract  its  active  principles  or  simple 
Iiifusion  is  sufficient.  By  extracting  the  coffee  with  water,  either  by 
percolation  or  decoction,  and  evaporating  to  a  syrup,  which  is  then 
treated  from  five  to  eight  times  with  chloroform  at  nearly  60°  till  all 
the  caffeina  has  been  dissolved  out,  he  obtains  a  larger  quantity  than 
previous  experimenters.  Raw  beans  of  the  yellow  Java  kind  yielded 
'0-709 — 0.849  per  cent,  by  this  method,  while  they  gave  only  0-474  by 
Crarot's  method  of  precipitation  with  basic  lead  acetate.  AVhen  much 
roasted,  coffee  loses  a  certain  quantity  of  caffeina  which  sublimes, 
•whereas  it  loses  none  by  slight  roasting.  Notwithstanding  this,  the 
coffee  made  in  the  usual  way  by  percolation  from  strongly  roasted  cof- 
<f«e  contains  rather  more  caffeina  than  that  made  from  an  equal 
wight  of  slightly  roasted  coffee,  as  the  roasting  renders  it  more  easy 
to  extract. 
When  coffee  is  prepared  in  the  usual  domestic  fashion  by  pouring 
six  to  ten  times  its  weight  of  boiling  water  three  or  four  times  over 
ground  coffee,  nearly  the  whole  of  the  caffeina  is  extracted,  hardly 
one-fifth  of  it  remaining  in  the  grounds.  The  quantity  of  caffeina  in  a 
<eup  of  coffee  prepared  from  16§  grams  of  coffee  is  about  0.1  to  0*12 
