428 
Ed  itorial. 
j  Am.  Jour.  Phar», 
t     Sept.  1, 1873. 
that  this  is  due  to  the  fact  that  few  medical  students  pay  due  attention  to  the 
lecturer  on  chemistry.  This  may  be  the  case,  and,  in  our  opinion,  it  would  do 
no  harm  for  medical  students  to  go  through  a  regular  course  of  practical  chem- 
istry, as  we  conceive  it  to  be  conducive  of  superior  qualifications,  if  the  large 
majority  of  pharmaceutical  students  were  to  devote  considerable  of  their  time 
to  systematic  experiments  in  practical  and  analytical  chemistry.  Experience- 
is  by  far  the  best  teacher  of  manipulations  and  of  scientific  facts.  Where  this- 
experience  is  wanting,  tables  of  incompatibilities  are  often  resorted  to,  to  sup- 
ply this  deficient  knowledge.  These  tables  are  often  far  too  cumbersome,  and, 
instead  of  enumerating  what  certain  articles  should  not  be  combined  with,  the 
facts  are  often  arrived  at  much  better  by  stating  the  compounds  with  which 
they  may  be  mixed  without  causing  precipitates  or  decomposition.  Thus,  of 
nitrate  of  silver  it  may  be  said,  that  it  can  only  be  combined  with  nitrates  and 
pure  soluble  chlorates  ;  all  the  other  officinal  articles,  whether  organic  or  inor- 
ganic, will  either  cause  a  reduction  or  produce  insoluble  or  sparingly  soluble 
silver  compounds. 
It  must,  however,  be  remembered  that  certain  combinations  which  are  truly 
incompatible  in  a  chemical  sense,  are;  notwithstanding,  largely  employed  in 
medicine,  and  that  many  compounds,  insoluble  in  simple  solvents,  possess  con- 
siderable medicinal  activity.  Acetate  of  lead  is  prescribed  together  with 
tannin  or  opium  preparations,  quinia  with  tannin,  opium  with  astringents,  sul- 
phate of  zinc  with  acetate  of  lead,  &c,  and  many  of  such  combinations,  used' 
internally  as  well  as  externally,  have  been  sanctioned  by  high  authorities  and 
long  usage.  It  is,  therefore,  not  always  possible  for  the  pharmacist  to  deter- 
mine whether  the  intention  of  a  physician  can  be  arrived  at  by  following  lite- 
rally the  directions  of  the  prescription,  and  in  all  cases  of  novel  combinations 
which  are  followed  by  decomposition,  it  is  well  to  call  the  attention  of  the  phy- 
sician thereto;  such  care  and  attentiveness  will  always  be  appreciated  by  well- 
meaning  practitioners. 
We  remember  a  physician  who  wanted  a  clear  liquid  when  prescribing  ace- 
tate of  lead  and  sulphate  of  zinc.  On  explaining  to  him  that  either  the  sul- 
phate of  lead  formed  would  have  to  be  filtered  out,  or  the  acetate  of  zinc  sub- 
stituted for  the  sulphate,  he  at  once  directed  the  latter  to  be  done. 
Nitrate  of  siver  dissolved  in  distilled  water  is  often  directed  by  physicians  to 
be  put  up  in  dark  colored  vials.  We  have  explained  to  several  that  the  solu- 
tion is  not  blackened  by  the  influence  of  the  light,  but  mainly  in  consf  quence- 
of  the  contact  with  inorganic  matter,  such  as  dust,  hair  pencil,  cork,  volatile 
oil  (if  rose-water  is  directed),  and  the  like.  Many  of  these  practitioners  sub- 
sequently prescribed  silver  solution  in  ordinary  glass  stoppered  vials. 
But  it  is  useless  to  enumerate  instances  of  this  kind.  We  merely  desire  to 
draw  attention  to  one  of  the  prescriptions  sent  us,  which  appears  to  be  written 
with  such  a  glaring  disregard  of  chemical  laws,  that  the  physician  should  have 
been  consulted  before  it  was  dispensed.  The  prescription  alluded  to  is  as  fol- 
lows : 
R.    Potass.  Iod.,       .  .  .  .  ^i, 
Argenti  Nitr.,  .  .  ■  3h 
Aquae,      .....    *iv.  Mix.. 
