Varieties.  129 
ments  and  treated  with  boiling  water,  which  dissolves  about  one-half  the  ash/' 
*'The  liquid,  thus  obtained,  is  evaporated,  and  in  cooling,  the  more  crystallizable 
salts  separate,  namely,  sulphate  and  carbonate  of  sodium,  with  some  chloride  of 
potassium.  The  mother-liquor  still  contains  the  iodide  of  sodium,  sulphite  of  sodium, 
sulphide  and  carbonate  of  sodium." 
"  The  liquor  is  then  mixed  with  sulphuric  acid,  and  allowed  to  stand  for  some 
hours.  Carbonic  and  sulphurous  acid  and  sulphuretted  hydrogen  gases  escape,  a 
fresh  quantity  of  sulphate  of  sodium  crystallizing  out,  mixed  with  a  precipitate  of 
.sulphur." 
"  The  supernatant  acid-liquor  is  then  transferred  to  the  still,  and  then  heated  and 
binoxide  of  manganese  added.  The  iodine  sublimes  into  condensers,  and  may  be 
purified  by  resublimation." 
"  The  average  produce  of  a  ton  of  kelp  is  about  ten  ( lo)  pounds  of  iodine.  Besides 
Iodine,  kelp  yields  muriate  and  sulphate  of  potassium." 
"  Iodine  is  also  made  in  Peru,  from  the  mother-liquor  of  the  '  caliche,'  which 
contains,  on  an  average,  about  one-third  of  one  per  cent,  of  iodate  of  soduim." 
*'  Iodine  is  imported  into  England  as  iodine  and  iodide  of  copper.  The  present 
quotation  is  %d.  per  ounce.  Since  July,  1874,  price  has,  in  consequence  of  the 
accumulation  of  the  Chilian  make  in  England  and  on  the  continent  of  Europe, 
gradually  declined  from  one  shilling  to  the  above  quotation." 
"  The  demand  for  the  article  not  being  sufficient  to  absorb  the  Chilian  importa- 
tions, as  well  as  the  undiminished  production  of  Scotland,  it  is  now  thought  that  we 
are  at  a  point  where  makers,  either  in  Peru  or  in  Scotland — or  probably  in  both 
countries — will  regulate  their  productions  more  in  accordance  with  the  wants  of  con- 
sumers. Indeed,  there  are  already  symptoms  of  such  a  policy  being  adopted  by 
makers  and  importers,  and  therefore  buyers  have  great  confidence  in  the  stability  of 
prices,  and  are  making  contracts  with  greater  freedom." 
^^Peru. — Regarding  iodine,  we  beg  to  state  that  we  have  never  heard  of  its  being 
produced  in  Chili,  but  only  in  Peru,  on  this  side.  It  is  produced  in  the  province  of 
Tarapaca,  out  of  the  'caliche.' 
"In  our  *  officinas,'  we  produce  it  in  the  form  of  iodide  of  copper,  which  contains 
about  60  per  cent,  of  pure  iodine.  This  iodide  of  copper  has  been  frequently  sent 
to  London,  but  it  has  met  with  very  few  buyers.  Of  late  it  has  been  sent  to  Ger- 
many, where  it  is  sold  in  its  original  form  as  iodide,  or  after  having  been  trans- 
formed into  kalium  iodatum  or  iodum  resublimatum.  .... 
"  In  some  of  our  '  officinas,'  in  Tarapaca,  it  is  produced  in  the  form  of  pure 
iodine,  and,  so  far  as  we  know,  sent,  for  sale,  to  England. 
"  When,  formerly,  the  production  of  iodine  was  a  monopoly  in  this  country,  it 
was  separated  in  the  form  of  moist,  diity  paste  5  but  now  this  has  ceased. 
"The  form  in  which  the  iodine  is  extracted  out  of  the  'caliche,'  depends  upon 
the  opinions  of  the  different  chemists.  Some  consider  that  the  form  of  cuprum 
iodidum  is  the  most  profitable  one,  and  that  the  production  of  pure  iodine  is 
too  expensive.  The  necessary  arrangements  for  the  manufacture  of  iodine  are  quite 
costly,  and  the  machinery  to  be  used  requires  a  large  sum  of  money,  and  therefore 
only  iu  few  '  officinas'  in  Tarapaca,  this  article,  as  such  is  produced. 
"  The  manufacturers  all  consign  their  product  to  England,  or  elsewhere,  so  that 
there  is  no  possibility  to  buy  it  here  in  this  country. 
9 
Am.  Jour.  Pharm. 
Mar.  1875. 
