ANTAGONISM  OF  ATROPIA  AND  MORPHIA,  ETC.  389 
When  prepared  by  either  of  the  above  methods,  spirits  of 
mindererus  is  a  colorless  liquid,  of  a  sweetish  saline  taste,  very 
agreeable  to  patients  suffering  from  fever;  the  solution  should 
not  yield  a  precipitate  with  nitrate  of  silver,  chloride  of  barium 
or  acetate  of  lead,  nor  be  darkened  by  sulphuretted  hydrogen. — 
Med.  and  Surg.  Reporter,  July  15,  1865. 
ON  THE  ANTAGONISM  OF  ATROPIA  AND  MORPHIA,  &c. 
By  Drs.  Weir  Mitchell,  Keen  and  Morehouse. 
The  foregoing  experiments  and  observations  authorize  us,  we 
think,  to  draw  the  following  conclusions  as  to  the  use  of  hypo- 
dermic injections,  and  as  to  the  antagonism  of  atropia  and 
morphia : — 
1.  Conia,  atropia,  and  daturia  have  no  power  to  lessen  pain 
when  used  subdermally. 
2.  Morphia  thus  used  is  of  the  utmost  value  to  relieve  pain, 
and  is  most  potent,  in  certain  forms  of  neuralgia,  the  nearer  it 
is  applied  to  the  seat  of  the  suffering. 
3.  Morphia  lowers  the  pulse  slightly  or  not  at  all ;  atropia 
usually  lowers  the  pulse  a  few  beats  within  ten  minutes,  and  then 
raises  it  twenty  to  fifty  beats  within  an  hour.  The  pulse  finally 
falls  about  the  tenth  hour  below  the  normal  number,  and  regains 
its  healthy  rate  within  twenty-four  hours. 
4.  Morphia  has  no  power  to  prevent  atropia  from  thus  in- 
influencing  the  pulse,  so  that,  as  regards  the  circulation,  they 
do  not  counteract  one  another. 
5.  During  the  change  of  the  pulse  under  atropia,  the  number 
of  respirations  is  hardly  altered  at  all. 
6.  As  regards  the  eye,  the  two  agents  in  question  are  mutually 
antagonistic,  but  atropia  continues  to' act  for  a  much  longer  time 
than  morphia. 
7.  The  cerebral  symptoms  caused  by  either  drug  are,  to  a 
great  extent,  capable  of  being  overcome  by  the  other,  but  owing 
to  the  different  rates  at  which  they  move  to  affect  the  system,  it 
is  not  easy  to  obtain  a  perfect  balance  of  effects,  and  this  is  made 
the  more  difficult  from  the  fact  already  mentioned,  that  atropia 
has  the  greater  duration  of  toxic  activity. 
