Amj^yri8P9Sarm'}  Observations  on  Some  Fluid  Extracts.  333 
sufficient  powder  on  one  slide  to  make  six  or  more  useful  slides.  The 
thinner  the  layer  of  powder,  and,  one  might  say,  the  less  of  it  there 
is,  the  easier  the  mount  can  be  examined. 
Hard  Oil  Finish. — The  writer  would  recommend  a  trial  of  hard  oil 
finish  (Berry  Bros.  "  white  ")  as  a  substitute  for  the  smeary,  sticky 
benzol  balsam,  it  being  much  more  agreeable  to  handle,  and  drying 
in  a  much  shorter  time.  Its  drawbacks  are  that  i-t  imparts  a 
decidedly  yellowish  cast  to  the  mount,  and  that  the  mounts  are  not 
so  glassy-like  as  the  pure  balsam  mounts. 
Adulterations. — It  is  advisable  to  become  familiar  with  the  micro- 
scopical appearance  (both  dry,  and  in  different  media)  of  the  follow- 
ing substances,  which  are  most  commonly  met  with  as  impurities 
and  adulterations:  Fibres,  starches,  wheat,  rye,  corn,  rice  and  oat 
flour,  ground  cocoanut  shells  (not  cacao),  cedarwood  (''se^ar-box 
wood"),  mineral  colors  (chrome  yellow,  Venetian  red,  Spanish 
brown,  oxide  of  iron),  sand,  charcoal,  dried  bread  ("  cracker  dust  "). 
OBSERVATIONS  ON  SOME  FLUID  EXTRACTS. 
Abstracts  from  Theses. 
Extr actum  Buchu  Fluidum. — Edward  Moor,  Jr.,  Ph.G.,  made  a 
series  of  experiments  with  the  view  of  determining  the  amount  of 
soluble  matter  taken  up  from  short  buchu  leaves,  in  No.  60  powder 
in  different  portions  of  percolate.  1,000  grams  of  the  powder  were 
used  for  each  experiment.  In  Nos.  2  and  6  the  ordinary  percolator 
of  rather  large  diameter  was  employed,  while  for  the  remaining  four 
the  narrow  Oldberg's  percolator  was  taken.  The  menstruum  was 
that  directed  by  the  Pharmacopoeia.  In  the  two  experiments  made 
by  the  pharmacopoeial  process  the  first  portion  reserved  measured 
850  cc,  and  the  weaker  percolates  were  collected  in  fractions  of 
1 ,000  cc.  Commencing  in  experiment  No.  3  with  repercolation,  the 
first  portion  reserved  measured  750  cc,  and  the  weaker  portions 
were  again  collected  in  fractions  of  1 ,000  cc.  For  the  remaining  three 
percolations  the  weaker  percolates  of  the  preceding  experiment 
were  employed  in  the  place  of  alcohol  and  water,  and  each  of  the 
five  portions  of  percolate  measured  1,000  cc.  The  first  portions  of 
the  repercolation  experiments  correspond  to  the  finished  fluid 
extract.  The  amount  of  extractive  matter  taken  up  was  determined 
by  evaporating,  in  a  water  bath,  100  cc.  of  each  fraction  to  nearly 
a  pilular  consistence.    The  finished  fluid  extract  made  by  process 
