ON  BURGUNDY  PITCH. 
545 
stem  of  the  Spruce  Fir,  Abies  excelsa,  D.  C.  (Pinus  Abies,  L., 
P.  excclsa,  Lam.),  melted  and  strained.  They  have  thus  fol- 
lowed the  London  College  of  Physicians,  which  for  nearly  a  cen- 
tury and  a  half  has  included  this  substance  in  its  Materia  Med- 
ica,  indicating  in  the  latter  editions  of  its  pharmacopoeia  a  simi- 
lar botanical  origin. 
On  the  Continent  the  term  Pix  Burgnndica  (which  is  not  fre- 
quently applied)  appears  to  have  a  less  definite  signification  than 
with  us,  being  used  synonymously  with  Resina  alba,  to  designate 
the  resins  of  various  coniferous  trees  after  purification,  by  being 
boiled  in  Yfater  and  strained.  The  following  description  is  trans- 
lated from  one  of  the  more  recent  and  esteemed  works  on  phar- 
macology, that  of  the  late  Dr.  Berg  : — * 
"  White  Resin,  White  Pitch,  Yellow  Resin,  Yellow  Pitch  ( Weis- 
ses  Harz,  weisses  Peek,  gelbes  Harz,  gelbes  Peek),  Resina  s, 
Pix  flava  s.  citrina. 
"  It  is  obtained  by  melting  common  resin,  with  the  frequent 
additions  of  water,  and  subsequently  straining.  According  as 
the  melting  has  lasted  a  longer  or  shorter  time,  the  resin  remains 
paler  in  color,  and  constitutes  White  Resin,  or  becomes  darker, 
and  is  called  Yellow  Resin,  and  is  thereby  richer  or  poorer  in  oil 
of  turpentine.  The  first,  owing  to  the  water  which  it  contains, 
is  almost  entirely  opaque,  white,  brittle,  and  becomes  gradually 
yellow.  The  second,  through  the  formation  of  a  little  colopholic 
acid,  by  reason  of  the  longer  melting,  is  of  a  yellow,  dark  yel- 
low, or  brownish,  color,  very  brittle,  here  and  there  clear,  and 
has  a  conchoidal,  glassy  fracture.  An  inferior  kind,  called 
White  Pitch,  is  obtained  from  the  resin  that  is  first  produced  in 
the  manufacture  of  tar,  and  has  a  brownish  yellow  color.  The 
true  Burgundy  Resin  or  Pitch,  {Resina  s.  Pix  Burgnndica)  is 
the  similarly  prepared  resin  of  Picea  excelsa  and  Pinus  Pinaster, 
which  is  brought  into  commerce  in  the  form  of  dull,  dirty-yellow, 
brittle  masses,  of  a  glassy  fracture,  softening  in  the  hand.  Or- 
dinary Burgundy  Pitch  is  White  Resin,  which  has  been  gently 
melted  for  a  short  time  without  the  addition  of  water,  so  that  it 
is  in  fact  freed  from  a  part  of  its  water,  but  has  not  yet  acquired 
the  brown  color  of  colophony." 
*  Pharmazeutische  Waarenkunde,  Berlin,  1863,  p.  566. 
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