214 
EXTRACT  OF  HEMLOCK  BARK. 
mentation,  that  is  to  say,  myrtle  wine,  acquires  by  time  a  pecu- 
liar ethereal,  very  agreeable  odor,  which  is  the  boquet  of  the 
wine.  The  same  juice,  not  fermented,  gives  by  evaporation  a 
syrupy  sweet  substance  like  that  from  grape  juice. 
Myrtle  wine,  when  evaporated  to  a  tenth  part,  and  allowed  to 
repose  during  twenty-four  hours,  deposits  crystals  of  cream  of 
tartar.  This  same  wine,  agitated  with  double  its  volume  of  a 
mixure  of  ether  and  ordinary  alcohol  in  equal  parts,  deposits 
little  crystals  of  cream  of  tartar  on  the  sides  of  a  matrass, 
well  stopped,  after  twenty -four  hours  repose. 
Lastly,  this  wine,  besides  cream  of  tartar,  contains  free  tar- 
taric acid,  which  can  be  precipitated  by  alcoholic  ether,  after 
transformation  into  cream  of  tartar,  by  adding  a  little  potassa. 
All  these  experiments  show  a  close  relationship  between  the 
fruit  of  the  grape  and  that  of  this  myrtle  of  Australia. 
The  myrtle  indigenous  to  Sicily,  bearing  small  white  fruit 
which  contains  cream  of  tartar  and  free  tartaric  acid,  also  will 
yield  wine. — Jour,  de  Pharmacie,  Jan.,  1866.        W.  P.,  Jr. 
EXTRACT  OF  HEMLOCK  BARK  {ABIES  CANADENSIS)— 
A  NEW  AND  VERY  CHEAP  ASTRINGENT. 
By  N.  Spencer  Thomas. 
Mr.  Editor: — Having  become  extensively  engaged  in  the 
manufacture  of  Extract  of  Hemlock  Bark  "  evaporated  in 
vacuo  "  for  tanning  leather,  I  have  frequently  observed  a  very 
great  similarity  between  it  and  the  Extract  of  Rhatany,  of 
which  I  used  to  make  large  quantities,  both  for  my  own  sales 
and  for  other  parties.  The  Extract  of  Hemlock  seems  to  have 
exactly  the  same  appearance,  both  before  and  after  drying,  as 
the  Extract  of  Rhatany.  As  far  as  I  know,  it  has  no  other 
properties  about  it  than  the  astringency  of  the  tannic  acid.  I 
should  suppose  it  would  answer  all  the  purposes  for  which  Ex- 
tract of  Rhatany  is  used  in  medicine  and  for  the  purposes  of 
dyeing  its  own  natural  tan  color,  and  black,  and  also  for  making 
ink.  As  it  is  the  cheapest  form  in  which  tannic  acid  can  be  pur- 
chased, it  will  undoubtedly  be  applied  to  many  useful  purposes 
when  it  becomes  known.    As  I  am  under  the  impression  tha 
