FACILITIES  FOR  DISPENSING  MEDICINES. 
545 
of  water,  then  drop  carefully  into  it  concentrated  sulphuric  acid, 
and  stir  until  the  quinine  is  dissolved ;  then  add  sufficient  water 
to  make  the  whole  measure  ten  fluidounces.  Ten  parts  of  this 
solution  will  represent  one  part  of  quinine. 
A  similar  solution  may  be  made  with  aromatic  sulphuric  acid. 
2.  A  Solution  of  Nitrate  of  Silver.* — The  exact  weighing  of 
nitrate  of  silver  in  small  quantities  is  very  difficult,  and  takes 
up  a  great  deal  of  time,  which  in  dispensing  is  of  great  impor- 
tance. The  solution  is  made  by  dissolving  an  ounce  of  nitrate 
of  silver  in  sufficient  distilled  water  to  make  it  measure  ten  fluid- 
ounces.  This  solution  has  to  be  kept  in  dark-colored  bottles,  to 
prevent  its  decomposition  by  light. 
3.  A  Solution  of  Chloride  of  Zinc. — Chloride  of  zinc,  being 
a  deliquescent  salt,  will  soon  become  unfit  for  weighing  by  using 
it  often.  The  solution  is  made  in  the  same  way  as  the  above,  by 
dissolving  one  ounce  of  chloride  of  zinc  in  sufficient  distilled 
water  to  make  it  measure  ten  fluidounces. 
4.  A  Mixture  of  Strychnia  with  Sugar. — This  is  an  import- 
ant mixture,  as  strychnia  can  not  be  too  carefully  handled. 
Doses  of  one-twelfth,  one-eighth  or  one-quarter  of  a  grain  can 
not  be  weighed  with  as  much  accuracy  as  when  mixed  with 
sugar ;  the  lightest  breeze  of  air  often  affecting  the  correctness 
of  the  scale.  One  drachm  of  strychnia  mixed  wish  sufficient 
white  sugar  t  >  make  the  whole  weigh  twelve  drachms,  is  a  con- 
venient mixture  in  most  all  cases  where  small  portions  of  strych- 
nia are  prescribed. 
*  [The  propriety  of  this  recommendation  for  nitrate  of  silver,  may  be 
doubted — except  in  those  eases  where  the  demand  is  very  frequent. 
With  the  utmost  care  it  will  be  difficult  to  prevent  access  of  organic 
matter,  and  the  salt  is  so  easily  dissolved  that  a  mortar  is  not  needed. 
The  strychnia  mixture  is  another  instance  of  doubtful  propriety  as  a 
standard  preparation.  Less  than  half  a  grain  is  rarely  prescribed,  and 
the  care  required  in  weighing  it  is  a  salutary  accompaniment  of  the  dis- 
pensing of  so  potent  an  agent.  The  objection  is  mainly  in  the  increased 
liability  to  accident  by  complicating  the  process  of  dispensing-.  Strych- 
nia, atropia  and  other  powerful  alkaloids  should  be  each  kept  in  a  single  re- 
ceptacle— plainly  marked — and  when  dispensed  they  deserve  to  receive 
the  time  and  care  needful  to  measure  them  carefully.  W.  P.  Jr  ] 
35 
