'^M/rch'il'rsT  }  On  Pi^actical  Pharmacy.  *  99 
arrangement,  based  on  a  botanical  alliance  of  plants  yielding  drugs, 
all  the  simple  preparations  of  each  drug  being  together.  The 
most  simple  plan  is  that  of  the  Pharmacopoeia.  The  most  rational, 
and  that  which  appeals  most  forcibly  to  the  reflective  mind,  is  that  of 
groups  based  on  the  similarity  of  active  principles,  the  preparations 
of  each  drug  being  together.  Thus,  the  starches,  the  gums,  the  sac- 
charine drugs,  the  acid  fruits  and  their  products,  the  principal  vege- 
table acids,  the  alkaloids,  the  neutral  principles,  the  fixed  oils,  the 
volatile  oils,  the  astringents,  etc. 
We  hold  that  the  lecturer  on  Pharmacy  should  exhibit  a  fair  speci- 
men of  each  drug  the  preparations  of  which  he  is  speaking  about,  and 
in  important  cases  deteriorated  samples,  not  to  trench  on  Materia 
Medica,  but  to  serve  as  a  practical  text  in  his  remarks  upon  prepara- 
tions, tie  should  have  the  powder  of  the  drug  and  each  of  its  offici- 
nal preparations  when  these  are  at  all  important.  When  the  drug  is 
much  employed  in  infusion  or  decoction,  these  preparations  should  be 
at  hand,  as  the  infusion  of  digitalis  or  the  decoction  of  cinchona, 
so  as  to  point  out  their  peculiarities.  Before  speaking  of  the  prepa- 
rations of  a  drug,  its  proximate  constitution  should  always  be  stated, 
and  when  several  principles  have  been  isolated  for  medical  use,  the 
mode  of  preparing  these  should  be  first  dwelt  upon.  This  acquaints 
the  student  with  the  nature  of  the  principles  entering  the  preparations 
discussed,  and  the  precautions  necessary  to  insure  their  solution  or  to 
avoid  their  injury. 
Where  preparations  are  liable  to  deteriorate  by  age,  it  is  well  to 
have  samples  for  illustration,  a  point  easy  to  accomplish  after  several 
years  of  experience,  and  in  relation  to  tinctures,  extracts,  syrups  and 
the  volatile  and  fixed  oils,  a  valuable  museum  will  soon  accumulate, 
illustrating  some  curious  points  in  relation  to  the  action  of  lights 
oxygen,  and  eremacausis,  together  with  the  influence  of  insects  and 
cryptogamic  vegetation. 
It  remains  to  say  a  few  words  in  regard  to  the  manner  of  treating 
the  subject  experimentally,  so  as  to  carry  out  the  ideas  above  stated. 
In  chemical  preparations  requiring  distillation  or  involving  the  con- 
densation of  gases,  like  the  ethers,  chloroform,  oil  of  wine,  water  and 
spirit  of  ammonia,  the  dehydration  and  rectification  of  alcohol,  the  pre- 
paration of  the  oils  of  cloves,  copaiba,  cubebs  and  the  distilled  waters 
and  spirits,  all  may  be  shown  without  difficulty  and  with  safety  by  suit- 
able preliminary  preparation  and  the  help  of  an  assistant  in  a  few 
