ASSAFCETIDA. 
351 
economy,  and  satisfactory  performance  induce  me  to  reproduce 
it  here. 
7*8  grains  of  argentic  nitrate  are  dissolved  in  60  cc.  of  water 
and  the  solution  is  divided  into  two  equal  portions.  A  solution 
of  3*11  grams,  potassio-sodic  tartrate  (Rochelle  salt)  in  1420  cc. 
of  water  being  brought  to  active  ebullition,  one  of  the  above 
portions  of  the  silver  solution  is  gradually  added,  the  boiling  is 
continued  8  or  10  minutes,  the  whole  is  allowed  to  cool  and  is 
then  filtered.    This  is  the  reducing  solution. 
To  the  second  portion  of  the  silver  solution,  caustic  ammonia 
is  added  till  the  precipitate  is  almost  redissolved,  care  being 
taken  to  avoid  an  excess,  and  then  355  cc.  of  water  being  added, 
the  whole  is  filtered. 
To  silver  the  glass,  equal  portions  of  these  two  fluids, 
thoroughly  mixed  and  perfectly  clear,  are  poured  upon  it. 
After  the  lapse  of  about  ten  minutes,  a  most  brilliant  layer  of 
metallic  silver  is  deposited,  which  may  be  thickened  to  any  de- 
sired extent  by  repeating  the  process.  The  film  is  protected  by 
a  layer  of  varnish. — G.  F.  B. — Amer,  Jour,  of  Science  and 
Arts,  March,  1867. 
ASSAFCETIDA. 
By  Dr.  J.  E.  Polak. 
Asafoetida,  called  in  Persian  Anguzeh  (of  which  our  word  asa 
may  be  an  abbreviation),  and  in  Arabic  Heltit  el  mumtin,  was  in 
former  times  abundant  on  the  trachyte  range  lying  between 
Ispahan  and  Mahiar.  Thither  the  assafoetida  collectors  from 
Khorassan  came  every  year  in  spring ;  they  surrounded  the 
plant  with  a  bank  of  stones,  cut  off  its  stem,  and  then  collected 
the  gum-resin.  But  as  they  left  no  stem  for  producing  seed,  * 
only  some  isolated  plants  are  now  to  be  found  in  this  locality. 
The  plant  is  however  still  plentiful  between  Abadeh  and  Murgab, 
where,  as  well  as  in  the  southern  province  of  Laar,  assafoetida  is 
collected.  About  Abadeh  in  the  spring  the  sheep  feed  on  the 
leaves  of  the  plants  ;  and  I  was  assured  by  credible  witnesses 
that  the  milk  and  butter  obtained  from  the  animals  thus  pastured, 
is  so  foetid  that  none  but  the  inhabitants  can  make  use  of  them. 
I  have  also  received  from  Herat,  through  an  English  physician, 
