86 
NEW  PROCESS  FOR  MAKING  FLUID  EXTRACTS. 
made  so  that  a  certain  amount  of  Liquid  shall  represent,  pound  by 
pound,  medically  the  same  quantity  of  crude  Drug,  and  which  are 
generally  obtained  by  extracting  with  a  large  excess  of  liquid  and  eva- 
porating down  to  the  desired  strength.  The  disadvantages  of  the  old 
process  are  well  known  to  every  chemist.  The  menstrua  used  for  making 
extracts  are  usually  of  an  etherial  or  volatile  nature — such  as  alcohol  of 
various  strength — and  their  strength  changes  by  evaporation  as  they  are 
exposed  for  a  longer  or  shorter  period  to  the  open  atmosphere.  If  such 
menstruum  is  poured  over  a  certain  drug,  it  dissolves  and  extracts  more 
or  less  of  the  soluble  parts  of  the  same  according  to  its  strength ;  but  if 
the  same  liquid  has  to  be  poured  repeatedly  over  the  same  drag,  it  loses 
its  strength  alcoholically,  and  some  of  those  portions  first  dissolved  are 
precipitated,  and  an  imperfect  extract  is  the  result.  The  value  of  the  ex- 
tract being  determined  by  its  alcoholic  strength  when  finished,  the  same 
or  similar  reasons  render  it  objectionable,  to  subject  the  extract,  when 
first  obtained,  to  the  evaporating  process ;  for  by  this  process,  the  vola- 
tile or  spirituous  parts  of  the  menstruum  are  first  evaporated,  and  the 
weaker  liquid  is  not  capable  to  keep  in  solution  many  of  those  parts  of 
the  drug  which  originally  had  been  dissolved  in  the  extract. 
These  objections  are  obviated  by  my  process,  which  is  carried  out  in 
the  following  manner  :  I  first  weigh  off  a  quantity  of  drug,  and  the  same 
quantity,  or  more  by  weight,  of  the  menstruum  or  liquid  by  means  of 
which  the  extract  is  to  be  made.  A  little  more  of  the  menstruum  being 
required,  as  a  little  moisture  is  left  in  at  last  pressing.  The  drug  being 
ground  to  proper  fineness,  is  then  dampened  with  a  small  portion  of  the 
liquid  and  subjected  to  heavy  pressure  (say  from  800  to  1000  tons), 
whereby  all  the  liquid,  or  nearly  so,  together  with  such  parts  of  the  drug 
which  have  dissolved  in  the  same,  is  expressed.  A  fresh  portion  of  the 
liquid  is  then  sprinkled  over  the  drug;  a  little  time  being  allowed  for  the 
liquid  to  dissolve  the  soluble  parts  of  the  drug,  and  the  same  process  of 
pressing  repeated  until  the  whole  quantity  of  liquid  is  used  up  and  the 
drug  is  completely  exhausted,  and  the  required  measure  obtained.  By  this 
process,  an  extract  is  obtained  which  represents,  pound  by  pound,  the 
crude  drug.  The  drug  is  perfectly  extracted,  and  the  menstruum  pre- 
serves its  original  strength  throughout,  so  that  the  same  is  capable  to 
retain  in  solution  all  those  parts  which  are  dissolved  during  the  various 
stages  of  the  process.  Furthermore,  by  my  process,  the  tedious  and  ex- 
pensive process  of  evaporation  is  dispensed  with,  and  concentrated  fluid 
extracts  of  any  description  can  be  produced  cheaper  and  better  than  by 
any  process  heretofore  applied  ;  and  as  the  application  of  heat  is  entirely 
avoided,  the  preparation  does  not  receive  the  injury  by  heat  that  all 
such  preparations  are  liable  to,  if  heat  is  applied  to  them,  no  matter  how 
carefully  applied  or  moderate  the  degree  of  temperature ;  and  further- 
more, the  change  thereby  of  strength  of  solvent  is  avoided. 
What  I  claim  as  new  and  desire  to  secure  by  Letters  Patent,  is  the 
