PHARMACY  OF  THE  CINCHONAS. 
401 
cheap,  easy,  perfect  and  speedy  exhaustion  of  its  medicinal  pro- 
perties, but  also  involves  the  leaving  behind  it  all  that  is  not 
medicinal,  because  such  matters  are  objectionable  not  only  as 
being  useless,  but  as  overloading  the  preparation.    The  question 
also  involves  the  extraction  of  the  medicinal  properties  in  their 
natural  condition  and  combinations  in  the  case  of  the  Cinchonas. 
In  assisting  to  decide  between  these  two  menstrua,  the  following 
results  of  a  carefully  conducted  experiment  may  be  given.  Two 
portions  of  16  troyounces  each  were  moistened  with  10  fluid- 
ounces  of  menstruum,  packed  as  nearly  alike  as  practicable,  in 
cylindrical  glass  percolators  of  the  same  size  and  form,  and  then 
managed  throughout  as  nearly  the  same  as  was  easily  practica- 
ble, the  only  intentional  difference  being  that  Alcohol  was  used 
with  one  and  Diluted  Alcohol  with  the  other.    The  percolates 
were  received  in  separate  portions,  the  first  portion  of  16  fs., 
aud  then  six  other  portions  of  8  fg.  each,  making  in  all  four 
pints  of  percolate  in  seven  portions.    From  each  portion,  as  re- 
ceived, 30  c.  c.  or  1  f 3 .  was  taken,  to  determine  the  proportion 
of  extract,  and  exactly  the  same  quantity  to  determine  the  im- 
pure alkaloids  by  the  process  of  assay  previously  described.  The 
portions  for  extract  were  dried  at  a  temperature  of  220°  F.,  or 
105°  C,  for  five  hours,  and  thus  gave  a  uniform  resinous  extract 
that  was  quite  dry.    The  portions  for  assay  were  managed  in  a 
uniform  way,  so  that  their  relations  as  series  might  be  tolerably 
accurate,  though  their  relations  to  the  Cinchona  might  be  less  so. 
This  trial  was  repeated  three  times  without  obtaining  the  uniform- 
ity of  result  that  was  desired  and  expected,  though  two  of  the 
pairs  agreed  within  useful  practical  limits,  and  all  agreed  in 
their  general  indications.    The  general  result  is  that  the  alco- 
holic menstruum  yields  the  most  extract  and  the  most  alkaloids, 
though  even  as  a  general  result,  this  must  be  received  subject  to 
farther  confirmation,  because  slight  differences  in  managing  the 
percolations  materially  modify  the  results.    For  example,  the 
alcoholic  menstruum,  everything  else  being  equal,  passes  most 
rapidly ;  and  this  circumstance  is  not  favorable  to  rapid  or  per- 
fect exhaustion  with  a  given  amount  of  menstruum.    Then  if  the 
packing  for  alcohol  be  harder,  so  as  to  bring  the  rate  of  percola- 
26 
