388  Oxy  Salts  oj  Bismuth.  {^"'iug-^iS^''"'' 
addition  of  the  latter  solution.  Although  yielding  an  anhydrous  pro- 
duct, it  will  be  free  from  more  than  traces  of  nitrate. 
BISMUTH  OXYIODIDE. 
Although  this  preparation  does  not  excite  so  much  attention  as  it 
did  about  a  year  ago,  attention  is  called  to  it  again  in  this  paper  be- 
cause of  the  examination  of  the  other  two  salts.  The  difficulties  which 
were  experienced  by  most  writers  on  this  subject  are  to  be  traced  to 
the  admixture  of  the  subnitrate  with  oxide,  the  latter  compound  not 
being  altered  by  KI,  and  also  preventing  a  portion  of  the  subnitrate 
from  undergoing  this  change  into  oxyiodide. 
But  now  knowing  the  limits  in  which  oxide  is  present  in  the  subni- 
trate, the  requisite  amount  of  HNO3  can  be  added  to  the  so-called  subni- 
trate, and  the  true  subnitrate  or  its  equivalent  obtained,  which  easily 
enters  into  reaction  with  KI  and  forms  the  pure  oxyiodide  and  KNO3. 
In  the  following  formula  sufficient  nitric  acid  is  used  to  convert  a 
subnitrate  containing  about  18  per  cent,  of  oxide  into  the  true  subni- 
trate, the  presence  of  the  small  quantity  of  free  HNO3  which  may  be 
present  being  in  a  large  quantity  of  water  exerts  no  decomposing 
action  upon  the  oxyiodide,  although  if  an  excess  of  KI  be  present, 
vapors  of  iodine  may  be  evolved. 
Bismuth  subnitrate   20  gm. 
HNO3  (sp.  gr.  1-42)   1  cc. 
Water   300  cc. 
KI   12  gm. 
Boil  the  subnitrate  with  the  nitric  acid  and  200  cc.  water  for  10 
minutes,  then  add  the  potassium  iodide  dissolved  in  100  cc.  water, 
boil  for  half  hour,  filter  and  wash  thoroughly  until  washings  cease  to 
give  more  than  turbidity  with  silver  nitrate.  Dry  at  a  temperature 
not  above  100°  C. 
This  furnishes  a  pure  salt,  and  although  in  an  extremely  fine  crys- 
talline powder,  shows  its  crystalline  characteristic  by  a  glistening  film 
on  the  interior  of  the  bottle  in  which  it  is  kept. 
lErgot  of  Oats  has  been  used  by  Dr.  Bousquet  ( Union  Med.,  Feb.  19, 1888) 
who  observed  that  its  action  was  as  prompt  and  lasting  as  that  of  ergot  of  rye, 
and  that  it  has  the  advantage  of  acting  as  a  general  excitant  and  restorative  in 
cases  of  prostration  from  prolonged  labor  or  copious  loss  of  blood. 
