180  Precautions  in  Dispensing  Poisons.  {^"^■4^^188^'" 
error  of  considering  all  medicines  dispensed  in  ordinary  bottles  as  non- 
poison  on  s. 
The  necessity  of  a  knowledge  of  tlie  chemical  reactions  of  poisons 
in  compounding  prescriptions  is  apjiarent.  The  neglect  to  paste  the 
label  "shake  the  vial"  on  the  bottle  containing  strychnia  has  been  the 
cause  of  death  through  the  patient  taking  an  overdose  when  the  last 
dose  in  the  bottle  was  given,  as  nearly  all  the  strychnia  in  the  pre- 
scription was  precipitated.  This  preci^iitation  would  take  place  in  the 
presence  of  many  substances  in  common  use  when  solutions  of  strych- 
nia, atropia,  morphia,  etc.,  are  mixed  with  them,  as  Huxham's  tinc- 
ture, salicylate  of  sodium,  etc.  Again,  some  innocent  substances  are- 
converted  into  a  dangerous  one,  as  calomel  into  a  corrosive  poison,, 
wlien  mixed  with  chloride  of  ammonium,  nitro-muriatic  or  hydrocy- 
anic acids. 
Where  there  are  two  substances  bearing  considerable  resemblance  to- 
each  other,  such  as  morphia  sulphate  and  quinia  sulphate,  it  is  perhaps 
as  well  to  keep  them  in  bottles  that  differ  both  in  appearance  and  size. 
It  has  been  my  practice  to  dispense  quinia  from  the  bottle  as  it  comes 
from  tlie  manufacturer,  whilst  the  morphia  has  been  kept  in  a  black- 
ened bottle.  It  is  also  a  good  plan  to  paint  the  store  bottles  contain- 
ing powerful  poisons  black,  as  a  distinguishing  mark,  and  those  that 
are  very  strong,  such  as  aconitia,  atropia,  etc.,  if  kept  in  small  vials 
and  these  again  placed  inside  larger  bottles  can  scarcely  be  dispensed 
in  mistake  for  other  substances. 
Contrary  to  the  practice  in  many  stores  I  believe  that  mistakes  can 
be  avoided  in  many  cases,  or,  I  may  say  in  most  cases  by  leaving  the 
bottles  from  which  medicines  have  l)een  taken  for  use  in  prescriptions 
on  some  part  of  the  counter,  especially  devoted  for  the  purpose,  so  that 
they  may  be  examined  before  the  customer  leaves  the  store  and  each 
bottle  compared  with  the  ingredients  of  the  prescription.  This  prac- 
tice, although  accompanied  with  some  inconvenience,  enables  the  pro- 
prietor or  superintendent  of  the  store  to  inspect  each  article  employed 
in  compounding,  so  that  nothing  need  be  left  to  the  responsibility  of 
inexperienced  persons,  Avhereas  this  cannot  be  done  if  the  bottles  are- 
taken  from  the  shelf  and  instantly  replaced,  unless  some  one  could 
follow  each  movement  of  each  individual  so  employed. 
Another  practice,  which  I  think  a  good  one,  is  to  paste  poison  or 
caution  labels  on  both  sides  of  the  bottles  that  require  to  be  so  marked 
when  sent  out  of  the  store,  so  that  there  will  be  an  additional  safe- 
