Am.  Jour.  Pharm. 
Nov.,  1877. 
Laboratory  Notes. 
551 
residue.  The  six  samples  were  free  from  cinchonia,  the  precipitates  being 
completely  dissolved  in  ether.  The  samples  yielded  respectively  2,  8, 
10,  the  remaining  three  15  per  cent,  of  alkaloid. 
Iodide  of  Potassium. — Five  different  samples  were  examined  by 
Eli  L.  Klopp.  They  all  had  an  alkaline  reaction,  were  free  from 
bromide  and  chloride,  but  with  the  exception  of  one,  contained  traces 
of  iodate. 
Tincture  and  Ammoniated  Tincture  of  Guaiac— Thos.  D. 
Williams  proposes  the  following  modification  of  the  officinal  process  : 
Six  troyounces  of  guaiac  resin  in  powder  No.  40  are  mixed  with  one 
and  a  half  pints  of  alcohol  in  a  half  gallon  bottle,  and  set  aside  in  a 
warm  place  for  24  hours.  The  liquid  is  then  poured  off,  the  undis- 
solved portion  packed  into  a  funnel,  the  alcoholic  liquid  first  poured 
upon  it,  and  the  percolation  finished  with  alcohol  until  two  pints  of 
tincture  have  been  obtained.  The  ammoniacal  tincture  may  be  con- 
veniently made  in  the  same  manner.  The  amount  of  insoluble  residue 
depends  upon  the  purity  of  the  guaiac  resin. 
Elixir  of  Hops.-— Jno.  H.  Kinports  has  found  the  following  formula 
to  yield  an  agreeable  preparation  :  Hops  gii,  cloves  and  anise  each 
gr.  lx,  cinnamon  gr.  lxxx,  all  in  fine  powder,  are  mixed  and  macerated  in  a 
portion  of  the  menstruum  obtained  by  dissolving  oil  of  orange  f^iiss  in 
alcohol  and  water  each  fgxii.  After  24  hours  the  powder  is  firmly 
packed  into  a  percolator  and  displaced  until  24  fluidounces  have  been 
obtained,  in  which  sugar  ^xii  is  dissolved.  Each  fluidounce  represents 
30  grains  of  hops,  the  bitter  taste  of  which  is  nicely  blended  with  the 
aromatics. 
Unguentum  Hydrargyri  Nitratis.— By  John  A.  Gingrich,  Ph. 
G.  Purified  ox  marrow  is  recommended  as  the  base  for  this  ointment. 
The  process  found  to  answer  best  is  the  one  first  suggested  by  Mr.  R. 
Rother,  in  1871.  The  fat  is  fused,  and  at  a  moderate  heat  treated  with 
one  half  the  nitric  acid  ordered  by  the  Pharmacopoeia,  and  after  the 
reaction  has  ceased,  the  mercury,  dissolved  in  the  other  half  of  the 
nitric  acid,  is  added.  Thus  prepared  it  retains  its  handsome  color  for  a 
long  time. 
Unguentum  Zinci  Oxidi.— Walter  W.  Koehler  accounts  for  the 
difficulties  encountered  by  many  in  preparing  this  ointment,  by  the  use 
of  the  commercial  oxide  of  zinc,  which  is  often  not  as  smooth  and 
