44^  Eugenic  Acid, 
Am.  Jour.  Pharm 
Sept.,  1880. 
green  color  was  accompanied  with  a  light  brown  layer  around  the  edges 
of  the  liquid. 
The  reaction  of  the  oil  of  pimento  and  acid  from  it  with  iodine 
gave  rise  to  a  red-brown  color  that  became  very  dark  on  standing 
twenty-four  hours  ;  oil  of  cloves  and  the  acid  from  it  when  treated  in 
like  manner  gave  similar  coloration,  but  not  so  deep  ;  when  treated 
with  mercuric  chloride  the  oil  of  cloves  and  its  acid  at  a  gentle  heat 
gave  a  deep  purple  color  ;  the  oil  of  pimento  under  similar  treatment 
gave  less  color. 
Strong  nitric  acid  produced  a  violent  reaction  with  each  of  the  oils, 
but  did  not  inflame.  The  color  by  oil  of  pimento  was  a  light  red- 
brown,  that  by  oil  of  cloves  darker. 
The  eugenic  acid  prepared  from  each  gave  effervescence  and  deep 
red-brown  color,  and  on  standing  for  twenty-four  hours  with  nitric  acid, 
both  oils  and  acid  gave  crystalline  deposits,  greater  in  amount  from  the 
oil  of  cloves  than  from  the  other.  The  crystals  were  very  soluble  in 
water,  yielding  precipitates  with  chloride  of  calcium  soluble  in  hydro- 
chloric but  insoluble  in  acetic  acid  ;  solution  of  permanganate  of  potas- 
sium with  sulphuric  acid  turns  light  brown  with  oil  of  pimento,  and 
this  becomes  darker  on  further  additions  of  the  reagent  ;  oil  of  cloves 
gives  similar  reactions,  but  more  decided.  The  eugenic  acid  derived 
from  both  oils  gives  crimson-red  color  \  both  oils  and  acids  decolorize 
the  solution  and  give  brown  precipitates. 
The  specific  gravity  of  eugenic  acid  was  found  by  experiment  to  be 
1*0785  ;  this  applies  to  acid  obtained  from  oil  of  pimento. 
Throughout  these  experiments  the  acid  prepared  from  the  oils  gave 
similar  reactions  under  the  same  treatment,  and  their  physical  proper- 
ties were  alike  \  the  odors  of  oils  of  pimento  and  bay  seemed  to  be 
due  to  their  hydrocarbons,  but  the  odor  of  that  from  oil  of  cloves  does 
not  have  the  characteristic  odor  of  the  oil.  Eugenic  acid  can  be 
obtained  more  economically  from  oil  of  cloves,  but  with  less  trouble 
from  oil  of  pimento. 
When  applied  to  the  skin  it  produces  a  burning  sensation.  Chlo- 
rine gas  when  passed  into  it  produces  a  greenish-white  turbidity, 
increasing  as  more  gas  is  passed  through  it.  Hydrochloric  acid  pro- 
duces the  same  color,  but  is  not  increased  in  intensity.  It  is  insoluble 
in  glycerin. 
After  drying  over  concentrated  sulphuric  acid,  at  a  low  temperature, 
small  crystals  were  seen  floating  on  the  top  of  the  eugenic  acid  ;  strong 
