PREPARATIONS  OF  CONIUM  MACULATUM,  ETC. 
267 
importance  to  ascertain  the  characters  of  the  materials  employed 
and  the  processes  adopted.  I  shall  not  scruple,  therefore,  to 
enter  into  a  somewhat  minute  description  of  them. 
Preparation  of  the  Tincture. — Two  ounces  and  a  half  of  the 
powdered  fruit,  mixed  with  fine  sand,  in  order  to  separate  the 
vegetable  particles,  and  bring  the  spirit  into  more  ready  contact 
with  them,  were  packed  in  the  percolator,  with  a  layer  of  sand 
above  and  below,  the  lower  aperture  of  the  percolator  being 
closed  with  a  piece  of  wash-leather.  The  fruit  was  then  ex- 
hausted by  the  passage,  drop  by  drop,  and  at  a  temperature  of 
62°  F.  of  5xx  of  proof  spirit.  The  percolation  was  preceded 
and  occasionally  interrupted  by  maceration, — the  one  process 
being  substituted  for  the  other  by  a  slight  rotation  of  the  stop- 
per. The  supernatant  spirit  was  preserved  perfectly  colorless 
by  the  upper  layer  of  sand  during  the  whole  of  the  time,  and 
thus  fresh  portions  of  pure  spirit  were  constantly  brought  into 
contact  with  the  separated  fragments  of  the  fruit.  It  is  obvious 
that  no  more  perfect  process  of  exhaustion  than  this  can  be  de- 
vised. It  is  one  which  Mr.  Hemingway  tells  me  he  has  con- 
stantly adopted  in  the  preparation  of  tinctures,  and  it  certainly 
appears  desirable  that  such  a  thoroughly  practical,  cleanly,  and 
effectual  process  should  be  universally  prescribed  for  the  pre- 
paration of  this  and  similar  pharmaceutical  products. 
The  fruit  used  was  a  fine  specimen,  and  probably  of  this  year's 
growth.  It  was  clean,  and  free  from  admixture  with  other  um- 
belliferous fruits.  The  albumen  was  firm  and  solid,  the  commis- 
sure convex,  the  groove  indicating  the  involution  of  the  albumen 
broad  and  deep,  and  the  crenations  of  the  ridges  well  formed — 
all  of  which  I  take  to  be  essential  characters  of  a  well  matured 
fruit.  My  friend  Professor  Bentley  has  also  examined  the  fruit 
and  pronounced  it  mature  and  good.  The  powder  was  prepared 
by  means  of  a  fineish  hair  sieve,  and  without  the  application  of 
heat.    It  evolved  a  strong  heavy  mousy  odor. 
When  14  ounces  of  the  spirit  had  percolated,  I  collected  f  ^ss 
in  a  watch-glass,  and  allowed  it  to  evaporate  spontaneously. 
Only  a  slight  yellowish-brown  film  of  varnish  remained  upon  the 
glass.    The  last  six  ounces  of  spirit  came  through  colorless. 
Mr.  Hemingway  exposed  the  marc  to  powerful  pressure,  and 
