URTICA  DIOICA,  (STINGING  NETTLE.) 
493 
odor  was  given  off  at  the  beginning,  but  none  toward  the  last. 
The  fluid  extract  thus  prepared  had  a  syrupy  consistence,  and  a 
dark  brown  color.  This  was  tried  in  doses  of  a  fluidounce  without 
any  perceptible  diuretic  effect,  which  led  to  the  conclusion  that 
the  diuretic  principle  was  lost  or  destroyed  in  the  process  of 
making. 
A  pound  and  a  half  of  the  bruised  root  was  macerated  in  seven 
pints  of  alcohol  (sp.  gr.  -835)  for  two  weeks.  The  tincture  when 
decanted  had  a  light  green  color  ;  it  was  distilled  till  nearly  all 
the  alcohol  was  recovered  ;  and  the  residue,  on  being  thrown  into 
water,  afforded  a  resinous  precipitate.  This  was  collected,  fur- 
ther purified  by  solution  in  alcohol  and  evaporation,  when  a  soft 
green  resin  was  obtained,  which  possessed  no  diuretic  power. 
The  portion  of  precipitate  left  undissolved  by  the  alcohol  was 
treated  by  ether,  which  took  up  from  it  a  brown  resinous  matter, 
that,  when  isolated,  had  no  diuretic  power. 
The  author  then  sought  for  the  diuretic  principle  in  the  dregs 
of  the  root  left  by  the  alcohol,  by  putting  it  in  a  still  with  eight 
pints  of  water,  and  distilled  first  one  pint,  which  was  set  aside 
on  account  of  its  being  strongly  alcoholic,  and  then  four  pints. 
Both  distillates  had  a  very  disagreeable  odor ;  the  alcoholic  dis- 
tillate had  a  greenish  yellow  color,  and  the  aqueous  was  milky. 
The  liquid  remaining  in  the  still  had  no  active  properties,  but 
both  the  distillates  were  quite  powerfully  diuretic. 
The  author  took  the  aqueous  distillate  in  doses  of  two  fluid- 
ounces,  at  intervals  of  half  an  hour,  until  he  had  taken  half  a  pint. 
The  effect  of  the  medicine  on  the  kidneys  became  evident  after  the 
second  dose,  and  did  not  pass  off  until  next  morning.  The  alco- 
holic distillate,  in  doses  of  half  a  fluidounce,  also  had  a  diuretic 
action. 
The  author's  reasons  for  believing  the  active  principle  to  be  a 
volatile  oil,  are,  that  it  has  a  warm  penetrating  odor,  made  a 
clear  solution  in  alcohol,  and  a  milky  mixture  with  water.  Tannin 
and  iodohydrargyrate  of  potassium  did  not  give  any  indications 
of  a  volatile  alkaloid.  He  did  not  pursue  the  subject  further  in 
this  direction,  but  states  that  among  the  fixed  principles  of  the 
root  are  starch,  gum,  albumen,  lignin,  sugar,  and  two  resins. 
