LIQUOR  OPII  COMPOSITUS. 
41 
tain  twice  or  three  times  the  quantities,  equal  to  two-thirds  or 
9ne  and  one-third  grains  of  sulphate  of  morphia.  These  doses 
are,  however,  under  ordinary  circumstances  poisonous ;  and  it  is 
always  best  with  this,  as  with  all  other  opiates,  to  give  them  in 
judiciously  timed  divided  doses  until  the  object  or  indication  is 
nearly  accomplished,  and  then  stop. 
When  opiates  are  given  incautiously  in  large  doses,  they  often 
seem  to  meet  the  indications  to  their  use  with  a  shock  or  con- 
cussion, overwhelming  all  the  powers ;  and  in  proportion  as  this 
impression  is  profound  and  continued,  and  in  proportion  as  it 
over-reaches  the  desired  object,  in  the  same  proportion  is  the 
subsequent  reaction,  producing  depression,  anorexia,  nausea, 
headache,  constipation,  etc.  Now  in  medicine,  as  in  mechanics, 
it  would  be  irrational  to  expect  to  control  a  reaction  independent 
of  control  of  the  initial  action,  and  therefore  opiates  are  not 
justly  chargeable  with  the  results  of  this  not  uncommon  misuse. 
On  the  other  hand,  however,  it  is  necessary  to  avoid  the  very 
small  doses  which  serve  only  to  stimulate  and  excite  the  sensori- 
um ;  and  therefore  no  direction  for  dosing  can  be  given  that  will 
be  more  than  usefully  suggestive  to  common  sense  and  good 
judgment,  acting  upon  a  clear  conception  of  just  what  is  required 
to  be  done,  and  how  easy  it  is  to  overdo  this. 
The  plea  for  assayed  preparations  in  medicine  and  pharmacy, 
in  order  to  attain  some  degree  of  accuracy  and  uniformity  in 
therapeutic  practice  and  results,  is  well  illustrated  in  the  instance 
of  opium.  It  is  well  understood  that  hardly  any  two  lumps  in  a 
case  of  ordinary  opium  yield  the  same  proportion  of  the  useful 
alkaloids,  and  that  the  different  lumps  have  as  great  a  variation 
as  from  five  per  cent,  in  some,  to  ten  or  eleven  per  cent,  in 
others.  It  is  also  well  known  that  by  the  escape  of  moisture  the 
proportion  of  alkaloids  is  constantly  varying  until  the  opium  is 
quite  dry.  It  is  also  well  known  that  opium  is  not  the  concrete 
juice  obtained  by  incision  from  the  unripe  heads  of  Papaver 
somniferum,  but  is  a  varying  proportion  of  this  juice  mixed  with 
a  heterogenous  mass  of  foreign  matter  in  a  more  or  less  solid 
condition,  and  that  the  productive  or  unproductive  seasons,  and 
the  variations  and  speculations  in  price,  have  an  influence  in  the 
yield  of  the  alkaloids  and  also  in  the  amount  of  foreign  matters 
