Amju°ne?i89hiarm'}  Volatile  Oil  of Ar  is  to  lochia  Reticulata.  263 
white  crystalline  camphor-like  body.  The  distillation  was  continued 
until  the  water  coming  over  was  perfectly  clear,  and  free  from  odor 
and  taste.  # 
The  contents  of  the  flask  were  now  one  layer  only  ;  this  was  care- 
fully acidified  with  dilute  sulphuric  acid,  the  distilling  flask  again 
attached  to  a  condenser  and  the  process  continued,  when  another 
crystalline  substance  was  obtained  along  with  the  watery  distillate. 
This  last  substance  was  redistilled  with  water  vapor,  when  it  again 
appeared,  as  before,  in  a  crystalline  form  of  white  dazzling  scales 
(much  like  benzoic  acid)  floating  on  the  distillate. 
This  distillate  possessed  an  acidulous  but  not  pleasant  taste  and  a 
peculiar,  somewhat  sour,  odor,  which  was  not  like  that  of  valerianic 
acid. 
The  crystals  and  also  the  distillate  were  strongly  acid,  and 
decomposed  sodium  and  calcium  carbonates  giving  soluble  salts. 
The  ammonium  salt  was  also  soluble.  When  converted  into  these 
salts  the  odor  disappeared,  but  was  again  produced  by  acidifying 
these  compounds  with  dilute  sulphuric  acid.  The  aqueous  solution 
of  the  free  acid  gave  with  ferric  chloride  a  bulky,  flesh-colored 
precipitate.  The  solution  of  its  neutral  salts  acted  in  the  same  way, 
but  the  filtrate  (containing  the  excess  of  the  iron  compound)  from 
the  precipitate  was  not  red.  The  crystalline  acid  substance  melted 
to  a  yellowish  liquid,  at  a  temperature  below  the  boiling  point  of 
water,  probably  at  about  65  °. 
In  a  second  attempt  to  prepare  more  of  the  above  acid  from  some 
of  the  fraction  containing  a~  small  amount  of  the  terpene,  the  acid 
separated  as  an  oily  liquid,  but  possessed  the  other  physical  prop- 
erties of  the  solid  acid,  and  gave  the  same  reaction  with  ferric 
chloride,  except  that  the  filtrate  in  the  case  of  its  salts  was  red  and 
upon  boiling  gave  a  red-brown  precipitate,  the  cause  of  which  (as 
was  proved  by  mercuric  chloride  and  by  the  acetic  ether  tests)  was 
due  to  acetic  acid. 
Another  experiment  with  the  pure  fraction  gave  a  solid  acid,  but 
the  small  quantity  operated  on  did  not  yield  sufficient  to  permit  it 
being  collected  as  a  solid  ;  no  oily  layer  separated  in  this  case ;  the 
distillate  was  found  to  be  free  from  acetic  acid,  and  in  all  physical 
properties  was  the  same  as  the  distillate  obtained  with  the  first 
crystalline  acid. 
It  might  be  said  by  way  of  parenthesis  that  an  accident  prevented 
