AmMa?fi8P9?arm"}        Pharmacopmal  Preparations.  255 
tendency  to  decomposition  and  becoming  muddy  and  dark-colored. 
Still  I  have  two  solutions  here  over  18  years  old,  no  extra  sterilizing 
precautions  were  taken  when  made ;  they  are  well  preserved  and 
are  perfectly  transparent,  although  they  have  slightly  changed  color. 
One  is  of  the  strength  of  1  grain  in  6  minims,  which  I  advocated 
in  a  paper  in  1870,1  the  other  is  1  grain  in  12  minims.  A  small 
dose  is  generally  preferred  for  hypodermic  injection,  but  the  strength 
of  1  grain  in  6  minims  is  considered  now  to  be  dangerously  strong 
in  the  hands  of  an  unskilled  operator.  The  more  nearly  saturated, 
however,  the  aqueous  solution  of  any  salt  or  crystalline  principle  is, 
the  better  it  will  keep ;  in  fact,  it  was  a  curious  argument  of  an 
advocate  for  spontaneous  generation  that  there  was  a  debatable  land 
between  that  of  crystallization  and  the  germination  of  organisms  in 
these  solutions — that  is,  between  the  growth  of  crystals  and  of 
organisms ;  this  applies  widely  in  pharmacy,  as  we  well  know,  in 
keeping  syrups  for  example.  A  nearly  perfect  syrup  consists  of  two 
parts  of  sugar  and  one  of  distilled  water ;  kept  at  a  uniform  temperate 
heat,  this  neither  crystallizes  nor  grows  fungi ;  and  our  solid  medici- 
nal extracts  are  preserved  if  they  contain  no  excess  of  moisture. 
Further,  these  remarks  especially  apply  to  the  official  solutions  of 
acetate  and  citrate  of  ammonium,  which  are  much  better  kept  in  a 
concentrated  form. 
The  salicylic  acid  solution  cannot  either  be  used  for  preparing  the 
hypodermic  injection  of  apomorphine ;  a  I  per  cent,  solution  of  the 
hydrochlorate  of  apomorphine  prepared  in  it  gives  a  quantity  of  a 
crystalline  deposit. 
Hydrochlorate  of  apomorphine  in  aqueous  solution  rapidly  devel- 
ops a  green  color ;  this  has  been  attributed  to  the  influence  of 
ammonia  in  the  atmosphere,  but  although  a  drop  of  solution  of 
ammonia  does  develop  the  green  color  immediately,  it  is  apparently 
not  due  to  this  alone.  This  salt  is  now  prepared  much  purer  than 
formerly,  and  it  is  also  not  so  soluble.  The  official  strength  of  the 
hypodermic  injection,  1  grain  in  50  minims,  i.e.,  1  in  45.5  parts,  of 
camphor  water  is  not  held  in  solution  at  6o°  F.  Dott  gives  the 
solubility  in  water  as  I  in  50.89,  Squire  as  I  in  56  to  60.  I  find 
1  part  in  60  of  boiled  and  cooled  distilled  water  dissolves, 
but  turns  green  within  a  few  hours,  but  if  acidulated  with  a  trace  of 
hydrochloric  acid,  say  an  equal  weight  of  the  official  diluted  hydro- 
1 Pharmaceutical  Journal,  [2]  Vol.  XI,  p.  480. 
