rt%rm- }       Glycerol  of  Nitrate  of  Bismuth.  2  5 
Now  I  think  that  henceforth  the  nitrate  should  be  kept  by  every 
chemist.  I  will  explain  why  I  think  so.  In  the  first  place  its  solution 
in  glycerin  will  prove  without  doubt  the  most  valuable  means  of  apply- 
ing the  remedy  to  any  external  surface,  and  in  the  next  place  it  will 
serve  equally  as  a  means  of  administering  bismuth  internally,  or  if  it 
be  desired  that  an  aqueous  solution  should  be  so  administered, 
even  that  may  be  done.  For  on  diluting  freely  the  glycerol  with 
water,  the  presence  of  glycerin,  as  I  find,  serves  to  delay  the  precipita- 
tion of  the  bismuth  by  water,  so  that  for  quite  half  an  hour,  at  the 
least,  no  turbidity  whatever  takes  place,  provided  the  water  used  be 
cold  water.  It  seems  to  me,  moreover,  that  the  presence  of  glycerin 
absolutely  prevents,  even  after  the  lapse  of  several  hours,  the  precipi- 
tation of  more  than  a  small  proportion  of  the  contained  nitrate ; 
insomuch  that  I  have  reason  to  believe  that  a  merely  moderate  dilution 
of  the  glycerol  might  leave  a  permanently  clear  solution,  but  I  have 
Dot  as  yet  made  quantitative  experiments  on  this  head. 
We  accordingly  have  henceforward  at  our  command  a  preparation 
which  has  for  long  been  a  desideratum,  and  one  the  contrivance  of 
which  has  baffled  the  efforts  of  the  compilers  of  our  "  Pharmacopoeia," 
and  indeed  the  efforts  of  every  one  who  has  devoted  attention  to  the 
point. 
I  was  assured  on  all  hands  that'  if  I  ever  should  succeed  in  getting 
o  to 
by  any  means  a  solution  of  nitrate  of  bismuth,  I  should  find  that  I  had 
'before  me  a  very  irritating  application  instead  of  what  I  desired,  that 
is  to  say,  a  bland  astringent.  But  I  have  sucked  my  glycerol  ;  I  have 
*even  rubbed  it  into  my  tongue,  and  I  find  it  to  be  merely  what  I  had 
designed  it  to  be,  and  that  is  a  bland  and  mild  astringent.  It  is  obvious 
that  a  soluble  preparation  of  a  drug  is  a  much  more  efficient  and  cer- 
tain mode  of  employing  it  than  an  insoluble  one,  and  that  a  simpler 
preparation  of  the  article  is  likely  to  prove  a  more  active  and  service- 
able mode  of  administering  it  than  any  more  complicated  preparation 
•of  it.  I  accordingly  lay  the  results  of  my  investigation  before  the 
pharmaceutical  body  in  the  confidence  that  they  will  soon  develop  its 
capabilities  in  a  very  considerable  degree. 
As  an  application  to  the  throat,  the  larynx,  the  vagina,  the  uterus 
and  the  urethra,  as  well  as  to  the  skin,  and  no  less  as  an  internal 
remedy,  I  believe  the  preparation  of  glycerol  of  nitrate  of  bismuth 
will  be  found  to  open  out  a  new  field  of  therapeutics. 
