240         THE  PRODUCTS  OF  THE  DISTILLATION  OF  ROSIN. 
tic  applications  of  this  plant  very  much  Journ.  and  Tram.  Md, 
Col.  Pharm,  March,  1861, /row  Repertoire  de  Pliarm,  S. 
THE  PRODUCTS  OF  THE  DISTILLATION  OF  ROSIN. 
By  J.  ScHEiL. 
The  product  of  the  first  action  of  heat  on  rosin  is  a  mobile 
liquid  of  a  yellow  color,  and  strong  but  not  repulsive  odor ;  at  a 
higher  temperature  a  thicker  iridescent  liquid  of  less  agreeable 
odor,  the  rosin  oil,  is  obtained. 
By  repeated  fractional  distillation  the  first  yields  two  liquids. 
One,  named  Colophonon  by  the  author,  is  colorless,  very  mobile, 
of  strong  refracting  power,  spec.  grav.  =  -84  at  74^0.,  and  boil- 
ing point  =97°  (206°  F.)  It  is  miscible  with  concentrated  sul- 
phuric acid  to  a  brown  liquid,  from  which  water  separates  a 
green  stratum,  resembling  thyme  and  rosemary  in  odor ;  hydro- 
chloric acid  has  a  similar  result ;  nitric  acid  yields  a  brown 
resin,  and  potassium,  with  the  evolution  of  gas,  a  brown  mass, 
turning  yellow.  After  heating  above  its  boiling  point,  with  the 
atmosphere  excluded,  it  has  an  odor  of  peppermint.  Its  com- 
position is  Co2Hjg02,  the  density  of  its  vapor  5-1. 
The  second  liquid  is  greenish  yellow,  boils  at  160°  C.  (320°  F.^ 
and  has  the  odor  and  other  properties  of  oil  of  turpentine;  it  is 
probably  identical  with  Deville's  terebene.  Both  liquids  are 
neutral  to  polarized  light. 
The  crude  rosin  oil  showed  the  composition  Q^^^fi  ;  the  re- 
fined, which  was  not  iridescent,  after  remaining  in  contact  with 
lime  for  24  hours,  =  Q^^^^O^. 
The  gases,  eliminated  by  the  dry  distillation,  were  collected 
at  three  different  periods.  The  atmospheric  oxygen  and  nitrogen 
in  the  retort  remained  nearly  in  the  same  relative  proportion  ; 
the  first  portion  of  the  gases  contained  14-96  per  cent,  carbonic 
acid,  11-48  per  cent,  carbonic  oxide,  and  5*89  per  cent,  elayle 
and  ditetryle.  Towards  the  close,  the  free  oxygen  had  nearly 
disappeared,  carbonic  acid  increased,  and  a  little  marsh  gas  was 
present ;  the  presence  of  propylene  could  not  be  proved.  Not- 
withstanding  a  long  condensing  tube  was  employed,  the  gases 
retain  a  portion  of  the  liquid  hydrocarbons,  and  it  is  probable 
that  the  disagreeable  odor  of  the  light-gas  is  due  to  such  a  body, 
^Ann,  d.  Qhem,  u.  Ph.,  xxxix.  96 — 102.  j.  M.  M. 
