5 1 2  Medicinal  Gum  Resins  of  Persia.    { AmNJ0°vu%87h6arm' 
color,  when  60  parts  more  of  the  oil  are  added,  and  the  liquid,  after 
standing,  is  decanted  and  kept  in  well-corked  bottles  sheltered  from 
the  light. 
It  differs  in  taste  but  little  from  the  ordinary  medicinal  codliver  oil- 
Exposed  to  the  light,  it  changes  after  a  few  days  to  a  red  brown  color, 
indicating  the  liberation  of  iodine.  Taste  and  color  furnish  a  good 
criterion  for  its  condition.  It  is  well  not  to  prepare  too  much  in  ad- 
vance.— Phar.  Jour,  and  Trans.,  July  8th,  from  Nieu  Tydschr.  voor  de 
Phar.  in  Nederland. 
Colorless  Tincture  of  Iodine. — Schonbein  states  that  ammonium  hypo- 
iodite  is  formed  when  iodine  acts  upon  an  excess  of  ammonia.  The 
hypoiodite  reacting  with  alcohol  produces  iodoform  in  the  same  manner 
as  chloroform  is  formed  by  the  action  of  calcium  hypochlorite  upon 
alcohol.  In  preparing  the  colorless  tincture  from  iodine,  ammonia- 
water  and  alcohol,  Wm.  H.  Darling  has  separated  some  iodoform,  and 
attributes  the  efficacy  of  this  tincture,  for  the  most  part,  to  the  iodo- 
form.— Ibid,  July  15. 
MEDICINAL  GUM  RESINS  OF  PERSIA. 
Ammoniacum  [Dorema  Ammoniacum,  Don  ) 
This  resin  is  called  Uschekh  in  Persia.  The  plant  grows  on  plateaux 
and  mountain  slopes  in  the  cold  climate  (Serdesir  or  Jeylak).  I  found 
it  on  the  far-stretching  plateaux  between  Mahiar  and  Yezdechast, 
especially  between  Aminabad  and  Yezdechast,  where,  together  with 
some  Salsola,  it  nearly  covered  the  whole  plain.  But  it  also  grows  in 
an  easterly  direction  from  Ispahan,  in  the  district  of  Ardistan,  by  the 
station  Najin  (on  the  route  to  Yezd).  According  to  the  authority  of 
the  inhabitants,  it  puts  forth  leaves  and  sprouts  towards  the  end  of 
March  ;  the  leaves  develop  quickly,  dry  just  as  rapidly,  and  serve  as 
excellent  food  for  sheep,  which  eat  them  with  avidity.  When  I  passed 
through  the  plateau  on  the  25th  of  June,  1859,  I  on^Y  saw  fallen  leaves, 
resembling  those  of  celery,  blown  about  by  the  wind.  The  stems,  how- 
ever, attain  a  height  of  about  six  feet,  and  I  could  easily  reach  the  tops  of 
them  on  horseback.  The  blossoming  season  was  already  over,  but  the 
sticky  seeds  were  still  young,  round  and  full  of  sap  (not  flattened  as  at 
the  end  of  the  journey) ;  above  all,  there  were  on  the  plants  and  tops 
small  tears  of  gum  resin.    The  bare  stems,  about  one  and  a  half  to 
