492  OIT  ASCLEPIAS  TUBEROSA   (PLEURISY  ROOT.) 
tained  in  so  small  a  quantity  that  its  other  properties  were  not 
investigated. 
When  the  powdered  bark  is  treated  with  ether,  the  tincture 
yields  by  evaporation  a  resinous  matter,  which,  when  taken  in- 
ternally, had  no  perceptible  action  analogous  to  the  alcoholic 
resin. 
The  bark,  when  distilled  with  water,  yields  a  transparent 
distillate  without  a  trace  of  volatile  oil. 
The  aqueous  extract  of  wahoo  bark  is  black,  intensely  bitter 
and  contains  much  extractive  matter.  Diluted  alcohol  is  the 
best  menstruum  for  exhausting  this  bark  in  preparing  from  it  a 
fluid  extract.  This  preparation  should  be  of  the  strength  of  an 
ounce  to  the  fluid  ounce,  and  may  be  given  as  a  purgative  in 
tablespoonful  doses,  and  as  a  tonic  in  teaspoonful  doses. 
ON  ASCLEPIAS  TUBEROSA  (PLEURISY  ROOT.j 
By  Elam  Rhoads. 
(Extracted  from  an  Inaugural  Essay.) 
The  Butterfly  weed,  or  pleurisy  root  as  it  is  frequently  called, 
is  a  perennial  plant  indigenous  to  the  United  States,  but  more 
abundant  south  than  north.  The  root  is  an  officinal  of  the 
U.  S.  Pharmacopoeia.  It  is  a  large,  irregularly  tuberous,  often 
branching,  somewhat  fleshy  root,  externally  brown,  internally 
white  and  striated,  and  in  the  recent  state  of  a  subacrid,  nause- 
ous taste.    When  dried,  its  taste  is  bitter  but  not  unpleasant. 
It  was  subjected  to  a  chemical  examination  ;  the  infusion, 
obtained  by  percolation  was  blackened  by  a  sesquisalt  of  iron, 
and  was  precipitated  by  solution  of  morphia  and  by  solution  of 
gelatin  ;  and  when  exhausted  by  the  latter,  the  filtered  solution 
yielded  a  black  coloration  with  sesquichloride  of  iron,  which 
was  discharged  by  heat — indicating  the  presence  of  tannic  and 
galUo  acids.  The  cold  infusion  was  precipitated  by  infusion  of 
galls  and  by  corrosive  sublimate,  and  when  boiled  was  rendered 
cloudy,  indicative  of  albumen. 
The  percolate  obtained  from  the  root  by  an  alkaline  solution 
afforded  a  gelatinous  precipitate  of  pectin  when  saturated  with 
dilute  sulphuric  acid. 
