412 
ON  CROTON  OIL. 
Crotonole,  is  obtained  in  the  following  manner.  Croton  oil  is 
agitated  with  a  sufficient  quantity  of  an  alcoholic  solution  of 
soda  to  form  a  milky  fluid  ;  this  is  gently  heated  for  some 
hours,  and  then,  by  the  addition  of  water  or  of  solution  of 
chloride  of  sodium,  the  milky  oil-particles  are  driven  to  the 
surface,  where  they  unite  to  form  a  continuous  oily  stratum. 
This  fatty  oil  is  entirely  got  rid  of  by  repeated  filtration 
through  a  moist  filter.  From  the  filtrate,  water  and  muriatic 
acid  separate  another  oil,  which  is  dissolved  in  cold  alcohol,  and 
mixed  with  fresh  hydrated  oxide  of  lead ;  by  this  means  a 
flocculent  precipitate  is  formed,  which  towards  the  end  often 
coheres  to  form  a  slimy  mass.  When  the  acid  reaction  has 
entirely  disappeared,  a  little  soda  and  a  large  quantity  of  water 
are  added,  by  which  the  fluid  is  first  rendered  milky,  .but  after- 
wards divides  into  a  clear  fluid  and  a  clear  oil  which  sinks  to 
the  bottom.  To  attain  this,  an  addition  of  large  quantities  of 
chloride  of  calcium  to  the  alcoholic  solution  was  frequently 
indispensable.  The  oil  thus  separated  is  washed  with  water  for 
some  time  upon  a  moist  filter,  and  then  dissolved  in  ether  ;  the 
ethereal  solution  is  agitated  with  water  in  a  cylindrical  glass, 
the  clear  etherial  solution  is  then  drawn  off  and  freed  from 
ether  in  a  capsule  in  vacuo.  The  crotonole  remains  as  a 
tenacious  mass,  resembling  turpentine.  It  is  colorless,  or  of  a 
slight  wine-yellow  color.  The  odor  is  weak  and  peculiar.  In 
its  properties  it  most  closely  approaches  the  alcohols. 
When  boiled  with  solution  of  potash  or  soda,  crotonole  is 
converted  into  a  brown,  resinous  matter,  which  has  no  action 
upon  the  skin. 
When  boiled  with  water,  or  still  better  with  dilute  sulphuric 
acid,  an  oil  with  a  mouldy  odor  appears  to  be  formed ;  this 
passes  over  in  considerable  a  quantity  when  water  acidified  with 
sulphuric  acid,  in  which  croton  oil  is  suspended,  is  distilled  ;  it 
floats  upon  the  distillate,  without  being  dissolved  in  the  least. 
It  is  only  the  oil  that  passes,  at  the  commencement,  that  is 
colorless ;  for  it  soon  goes  over,  nearly  black.  Without  the 
assistance  of  aqueous  vapors,  it  is  not  distillable ;  for  in  a  space 
exhausted  of  air  to  a  pressure  of  50  millims.  nothing  could  be 
distilled  even  at  392*  F.  ;  but  by  this  means  it  became  black 
