LARIXINIC  ACID. 
555 
offer.  Our  processes  can  be  applied  with  like  success  to  the 
manufacture  of  cane  sugar  as  well  as  sugar  refining.. — Chem. 
News,  May 10,  1862. 
ON  LARIXINIC  ACID,  A  CRYSTALLIZABLE  VOLATILE  PRIN- 
CIPLE FOUND  IN  THE  BARK  OF  THE  LARCH  TREE  (PINUS 
LARIX,  Linn.) 
•   By  Dr.  John  Stenhouse,  F.R.S. 
The  most  convenient  way  of  preparing  this  somewhat  sin- 
gular substance  consists  in  cutting  the  bark  of  the  larch  into 
small  pieces,  and  then  digesting  it  in  water  for  twenty-four 
hours,  at  a  temperature  of  about  80°  C.  The  solution,  which 
has  a  deep  reddish-brown  color,  is  then  poured  off  on  to  a  sec- 
ond portion  of  larch  bark,  and  digested  as  before.  The  con- 
centrated infusion  is  then  cautiously  heated  in  an  open  porce- 
lain dish,  at  the  temperature  of  about  80°  C,  till  it  is  converted 
into  a  syrup.  A  portion  of  this  syrup  is  then  distilled,  either 
in  glass  or  porcelain  retorts,  or,  what  is  better  than  either,  in 
a  silver  alembic.  Iron  retorts  cannot  be  employed  for  this  pur- 
pose, as  the  acetic  acid,  which  is  always  produced  during  distil- 
lation, by  forming  acetate  of  iron,  instantly  destroys  the  larix- 
inic  acid,  by  changing  it  into  a  deep  purple-colored  liquid. 
When  a  silver  alembic  cannot  be  procured,  a  very  convenient 
way  of  distilling  the  extract  of  the  larch  is  to  pour  it  into  a 
large  Florence  flask,  the  neck  of  which  is  passed  obliquely 
through  a  cork  or  bung,  which  is  inserted  into  a  glass  con- 
denser. When  the  flask  is  cautiously  heated  on  a  sand-bath, 
the  larixinic  acid  comes  over  with  the  first  portions  of  the 
liquid,  but  becomes  more  abundant  as  the  distillation  proceeds, 
and  usually  forms  large  flat  crystals,  which  cohdense  on  the 
sides  and  neck  of  the  receiver.  The  liquid  which  is  distilled 
over,  and  which  contains  the  greater  portion  of  the  larixinic 
acid,  should  be  poured  into  small  flat  basins,  and  cautiously  con- 
centrated at  about  60°  C.  When  the  greater  portion  of  the 
water  has  been  dissipated,  it  is  advisable,  especially  in  warm 
weather,  to  complete  the  operation  by  spontaneous  evaporation ; 
for  unless  the  concentration  of  the  aqueous  solution  of  larixinic 
acid  is  conducted  cautiously,  the  larixinic  acid  volatilises  along 
