428 
PRODUCTION  OF  IODINE  AND  BROMINE. 
Kreushnach,  Ure  found  10-8  grns. ;  in  Kissengen  water,  deter- 
mined bj  Kastner,  044  grns.  ;  at  Tenbury,  in  Worcestershire, 
examined  by  Dr.  Ure,  as  high  as  12*5  grns.  ;  and  at  Arnstadt, 
according  to  Hartung,  13-6  grns.  Iodine  occurs  in  far  less 
quantities,  from  mere  traces  to  2*2  grns.  per  gallon,  this  latter 
quantity  being  found  in  the  iodine  spring  at  Halle. 
In  the  United  States,  both  bromine  and  iodine  have  been 
detected  in  the  various  saline  and  mineral  springs.  Iodine  was 
first  detected  in  this  country,  in  the  Saratoga  Spring  waters,  by 
Drs.  Usher  and  Steel,  in  1830,  and  bromine  in  the  same  waters 
by  Dr.  A.  A.  Hayes,  and  in  the  salines  of  Onondaga  by  Prof.  B. 
Silliman,  in  the  same  year.  The  quantity  of  bromine  in  the 
spring  waters  of  Saratoga  county,  determined  by  Prof.  Chand- 
ler, reaches  3*63  grns.  per  gallon  in  the  water  of  one  of  the 
Artesian  wells,  the  largest  amount  of  iodine  found  being  0*2 
grn. ;  but  in  this  country,  as  in  Europe,  it  is  in  the  salines  that 
the  quantity  of  these  substances  becomes  of  economical  impor- 
tance, and  in  a  brine  of  the  Saginaw  valley.  Dr.  Chilton  found 
7*65  grns.  of  bromine;  at  Tarentum,  Pa.,  6  grns.  bromine  and 
4  grns.  iodine  were  reported  by  Slieren;  in  the  Salina  brine 
analyzed  by  Prof.  Goessmann,  however,  only  1'36  grns.  of  bro- 
mine per  gallon  are  reported. 
Besides  these  various  sources,  iodine  has  been  detected  in  the 
soda  deposits  of  Peru,  in  the  ashes  of  sponges,  and  in  the  ashes 
of  the  Spanish  barilla  plants.  Cod-liver  oil  is  said  to  owe  some 
of  its  medicinal  properties  to  a  trace  of  iodine.  Though  the 
distribution  of  bromine  and  iodine  is  thus  very  general,  yet 
owing  to  their  existence  in  such  comparatively  minute  quantities, 
the  sources  of  our  commercial  supply  are  much  more  restricted. 
Up  to  the  beginning  of  this  century  the  alkalies  of  commerce 
were  derived  from  the  ashes  of  plants,  and  the  burning  of  sea- 
weeds was  an  important  industry,  especially  in  Great  Britain 
and  Ireland. 
The  amount  of  ashes  of  sea-weed,  the  so-called  kelp,  reached 
its  maximum  production  in  1800,  when  20,000  tons  were  collected. 
To  produce  this,  400,000  tons  of  wet  weed  were  burned.  From 
this  time,  owing  to  the  removal  of  the  import  duty  and  to  the 
introduction  of  the  manufacture  of  soda  ash  from  common  salt, 
