Am.  Jour.  Pharm. 
Sept.,  1887. 
Gleanings  in  Materia  M*?dica. 
447 
a  little  empyreumatie  oil.  In  roasting  coffee  on  a  large  scale,  a  por- 
tion of  the  water  is  at  first  condensed  upon  the  cooler  portion  of  the 
charge,  where  it  dissolves  some  caffeine ;  this  solution  is  absorbed  by 
the  thin  membrane,  and  the  latter,  as  the  roasting  progresses,  is  de- 
tached and  carried  off  into  the  flue ;  this  appears  to  be  the  source  of 
caffeine  in  the  "  flights."  Properly  roasted  coffee  contains  1.3  per 
cent,  of  caffeine,  but  in  an  over-roasted  coffee,  which  had  lost  31.  7  per 
cent.,  only  1.25  caffeine  was  found,  while  by  calculation  it  should 
have  contained  1.61  per  cent. 
Infusion  of  coffee,  prepared  by  percolation  from  J  oz.  of  coffee  with 
sufficient  boiling  water  to  yield  3  fluid-ounces,  was  found  to  contain 
45  grains  of  extractive,  including  2*36  grains  of  caffeine,  about  12  per 
cent,  of  the  latter  remaining  in  the  grounds  (from  which  it  may  be 
exhausted  by  more  water).  A  cup  of  coffee  made  in  the  way  indica- 
ted may  be  expected  to  have  a  marked  effect  as  a  stimulant. — Phar. 
Jour,  and  Trans.,  April  9,  1887,  p.  821. 
Nettle  poison. — Some  time  ago  Dr.  G.  Haberlandt,  in  a  paper  read 
before  the  Academy  of  Sciences,  at  Vienna,  opposed  the  generally 
accepted  view  of  the  presence  of  formic  acid  in  the  stinging  hairs  of 
Urtica  dioica  Lin.,  and  U.  urens,  Lin.,  showing  that  formic  acid 
had  no  such  virulent  properties  in  the  minute  quantities  in  which  it 
could  be  present  in  the  nettle  hairs ;  he  considered  it  probable  that 
the  poison  was  a  non-volatile  albuminoid  compound,  perhaps  an 
unformed  ferment. 
David  Hooper,  however,  shows  (Phar.  Jour,  and  Trans.,  April  9, 
1887,  p.  822)  that  the  Nilgiri  nettle  (Girardinia  palmata,  WeddL, 
contains  in  its  hairs  a  volatile  acid,  reducing  permanganate  and  salts 
of  silver  and  mercury,  and  forming  a  lead  salt  soluble  in  water,  but 
insoluble  in  alcohol ;  this  behavior  points  to  formic  acid.  The  solid 
contents,  obtained  on  evaporation,  consisted  apparently  of  albuminous 
matter  with  a  trace  of  ash. 
Euphorbiumn  consists,  according  to  G.  Henke,  (Archiv  d.  Phar., 
1886,  p.  729-759,)  of  34-6.  euphorbone,  26*95  resin  soluble  in  ether, 
14*25  resin  insoluble  in  ether,  1*1  caoutchene,  1*5  malic  acid,  20*40 
gum  and  salts,  of  which  two-fifths  are  precipitated  by  alcohol,  and  1*2 
other  substances  soluble  in  ammonia.  Euphorbone  is  extracted  by 
petroleum  benzin  (boiling  point  65°C.  =  149CF.),  and  is  best  puri- 
fied by  dissolving  in  ether,  adding  alcohol  until  a  permanent  turbi- 
