AmMi?cbr;584.rm'}        Aqueous  Mixtures  of  Chlorate  of  Potash.  139 
observing  that  when  such  gargles,  etc.,  had  to  be  repeated  there  were 
very  often  present,  in  the  bottle  which  had  previously  contained  them, 
a  few  pretty  large  crystals  of  chlorate  of  potash.  A  short  time  since 
the  subject  was  again  brought  very  forcibly  under  my  notice  in  the 
following  manner. 
About  twelve  months  ago  I  dispensed  a  gargle  containing  ^iv  chlo- 
rate of  potash  in  eight  ounces  of  water.  About  one  half  had  been 
used  at  the  time  and  the  remainder  set  aside  until  about  two  months 
ago,  at  which  time  circumstances  arose  calling  for  the  use  of  a  similar 
remedy.  The  half  empty  bottle  was  brought  to  me  to  see  if  the  same 
gargle  would  be  suitable  for  this  case,  and  I  found  that  the  whole  of 
the  undissolved  chlorate  of  potash  had,  in  the  interval,  passed  from  a 
condition  of  fine  powder  to  that  of  pretty  large  tabular  crystals,  and 
the  gargle  was  therefore  in  a  state  quite  unfit  for  use. 
It  occurred  to  me  that  it  might  be  possible  to  prevent  the  chlorate 
resuming  the  crystalline  form,  at  least  for  a  reasonable  length  of  time, 
by  adding  to  the  gargle  some  substance  likely  to  interfere  with 
crystallization.  To  determine  this  point  the  following  mixtures  were 
prepared : 
No.  1.  Chlorate  of  potash  3j.  water  to  3j. 
No.  2.  Chlorate  of  potash  3j.  glycerin  3j.  water  to  ^j. 
No.  3.  Chlorate  of  potash  3j.  simple  syrup  3ij.  water  to 
No.  4.  Chlorate  of  potash  3j.  gum  arabic  gr.  x.  water  to  3j. 
No.  5.  Chlorate  of  potash  sj.  gum  tragacanth  gr.  iij.  water  to  3j. 
No.  6.  Chlorate  of  potash  3j.  honey  3j.  water  to  Ej. 
No.  7.  Chlorate  of  potash  3j.  treacle  sj.  water  to  ^j. 
The  chlorate  of  potash  was  in  each  case  reduced  to  very  fine  powder, 
and  the  mixtures  were  all  equally  exposed  to  the  variable  temperature 
of  an  ordinary  sitting-room. 
On  examining  the  specimens  about  twenty-four  hours  after  they  had 
been  so  exposed  I  found  that  in  every  one  of  them  a  portion  of  the 
chlorate  had  passed  into  the  condition  of  very  thin,  sharp-edged  tabu- 
lar crystals,  exhibiting  in  many  cases  iridescent  properties  of  thin  trans- 
parent plates.  The  time  of  examination  was  on  the  morning  of  the 
second  day  when  the  temperature  of  the  room  was  several  degrees  less 
than  it  had  been  in  the  course  of  the  previous  night;  a  circumstance 
which,  I  believe,  has  a  good  deal  to  do  with  the  rapid  change  of  the 
chlorate  from  a  state  of  fine  powder  to  that  of  sharp  crystals. 
When  the  temperature  of  the  room  rises  a  quantity  of  the  chlorate 
