Am.  Jour.  Pharm.  \ 
Dec.  1,  1872.  J 
A  New  Filter. 
541 
Wine  of  eucalyptus. — Eucalyptus  leaves,  dried  and  cut,      30  p. 
Alcohol  of  60  per  cent.,  .       .        60  p. 
White  wine,    ....     1000  p. 
Macerate  the  leaves  in  the  alcohol  for  24  hours,  add  the  wine,  ma- 
cerate for  ten  days,  express  and  filter. 
Extract  of  eucalyptus. — Eucalyptus  leaves  dried  and  cut,  1000  p. 
Water,  ...  .     5000  p. 
Obtain  by  distillation  the  volatile  oil.  Of  the  residue  in  the  still 
prepare  an  aqueous  extract,  which  treat  with  1000  p.  of  alcohol  of  60 
per  cent.,  filter,  concentrate  the  alcoholic  liquid  to  the  consistence  of 
an  extract,  to  which,  while  cooling,  add  the  volatile  oil  and  mix  inti- 
mately. 
Detection  and  estimation  of  Ground-nut  oil  in  olive  oil. — Renard. — 
10  grams,  of  the  oil  are  saponified,  the  soap  is  decomposed  by  HC1, 
and  the  fatty  acids  resulting  are  dissolved  in  50  c.  c.  of  90  per  cent, 
alcohol,  and  precipitated  with  acetate  of  lead.  The  precipitate  is  ex- 
hausted with  ether  to  remove  the  lead  oleate,  the  solid  fatty  acids  ob- 
tained by  boiling  the  residue  with  HC1  and  cooling,  are  dissolved  in 
50  c.  c.  alcohol  of  90  per  cent.,  and  cooled.  If  ground-nut  oil  be  pre- 
sent, abundant  crystals  of  arachidic  acid  will  form  in  the  liquid.  These 
may  be  removed  and  washed,  first  with  alcohol  at  90  per  cent.,  and 
then  with  70  per  cent.,  and  then  dissolved  in  boiling  absolute  alcohol, 
received  in  a  tared  dish,  evaporated  to  dryness  and  weighed.  Since 
pure  ground-nut  oil  contains  4-5  to  4  98  per  cent,  of  arachidic  acid,  it 
is  easy  to  calculate  the  amount  of  this  oil  present.  The  method  is  capa- 
ble of  detecting  an  adulteration  of  even  four  per  cent. — Amer.  Chem.y 
Oct.,  from  Compt.  rend.,  No.  23. 
A  NEW  FILTER. 
By  R.  Rother. 
For  most  pharmaceutical  purposes  the  ordinary  plaited  filter  meets 
all  indications.  But  for  analytical  operations  the  plaited  filter  cannot 
be  successfully  applied.  The  numerous  folds,  while  favoring  the 
rapid  transmission  of  liquids,  expose  too  much  surface  for  the  con- 
venient collection  of  precipitates,  and  at  the  same  time  greatly  and 
seriously  interfere  with  their  washing.  The  plain  filter  is  the  only 
practical  form  for  analytical  uses,  but  as  it  exposes  only  half  as  much 
surface  as  the  plaited  filter,  the  passage  of  the  liquid  will  naturally  be 
