a8  Churchill's  Tincture  of  Iodine.      {A™-  Jour-  Pharm- 
o°  J  January,  19 19. 
Napoleon's  wars,  Courtois  developed  a  process  for  the  manufacture 
of  artificial  saltpetre  or  sodium  nitrate.  He  employed  the  ashes  of 
seaweed  called  varec,  to  make  lye.  He  decomposed  the  extract  of 
the  ashes,  which  contained  sodium  carbonate  with  calcium  nitrate 
and  obtained  a  solution  of  sodium  nitrate  and  a  precipitate  of  cal- 
cium carbonate.  He  also  discovered  that  when  this  was  done  in  a 
copper  boiler  the  solution  attacked  the  metal.  By  further  experi- 
ments he  found  out  that  the  ashes  of  all  seaweed  had  the  same 
deteriorating  effect  on  copper.  Upon  investigating  this  more  thor- 
oughly he  discovered  that  after  the  crystallization  of  soda  from  the 
lye  of  kelp  the  remaining  mother  liquor  when  heated  with  sulphuric 
acid  evolved  violet  vapors  which  sublimed  into  scales  having  a  gray- 
black  color  and  a  bright  metalic  lustre.  He  also  found  out  that 
when  these  were  treated  with  ammonia  a  violent  explosion  resulted, 
and  he  noticed  that  the  scales  had  a  corrosive  action  on  organic 
matter. 
Courtois  communicated  his  experiments  to  his  friend  Clement, 
who.  on  November  20,  1813,  read  a  report  on  this  subject  before  the 
Academy  of  Sciences  at  Paris.  Sir  Humphry  Davy  was  one  of 
these  present  at  this  lecture  and  managed  to  obtain  some  of  the 
bright  metallic  crystals.  He  made  various  experiments  and  finallv 
concluded  that  this  new  substance  was  an  element.  The  French 
chemist  Gay-Lussac  named  the  element  iodine  from  the  Greek 
"  iodes,"  which  means  violet-colored.  However,  Sir  Humphry  Davy 
got  credit  for  the  discovery  of  the  elementary  nature  of  iodine. 
History  of  Churchill's  Tincture. 
Churchill's  tincture  of  iodine  was  originated  by  Dr.  Fleetwood 
Churchill,  the  celebrated  Dublin  gynaecologist,  professor  and  author, 
for  use  in  his  practice.  He  knew  that  iodine  was  a  strong  anti- 
septic and  also  had  an  astringent  action  and  could  be  used  success- 
fully in  gynaecology.  But  he  needed  a  "soluble  and  stronger  tinc- 
ture," one  which  would  readily  mix  with  water  and  not  have  the 
iodine  precipitated,  as  is  the  case  with  the  ordinary  tincture.  Dr. 
Churchill  then  made  the  addition  of  potassium  iodide  which  he  found 
would  keep  the  iodine  in  solution  and  prevent  its  precipitation  so  that 
the  preparation  would  be  soluble  in  water. 
