Amju°nUer;S?rnJ'}     Use  of  Wood  Alcohol  Pharmaceutically.  287 
vapor  causes  great  irritation  of  the  eyes  and  nose — almost  unbear- 
able, and  also  makes  the  exposed  skin  smart  and  tingle.  Even 
pure  methyl  alcohol  tincture  will  cause  irritation  of  the  nose  if  its 
vapor  is  inhaled,  an  irritation  quite  different  from  that  of  iodine. 
During  the  winter  I  made  a  number  of  experiments  on  wood  alcohol 
tincture  iodine,  having  a  number  of  cases  under  my  observation 
where  the  chest  was  painted  with  iodine  for  simple  cough  and  cold, 
painting  one  side  of  the  chest  with  wood  alcohol  tincture,  the  other 
with  grain  alcohol  tincture.  In  every  case  the  difference  was 
marked,  the  wood  alcohol  side  appeared  much  redder  the  second 
day,  there  was  sometimes  faint  blistering,  and  the  patients  declared 
that  this  side  "  burnt"  them  the  most.  In  applying  this  there  was 
often  caused  very  unpleasant  symptoms  from  the  irritating  effect  of 
the  vapor  on  the  eyes  and  nose,  one  case  of  mild  conjuctivitis  being 
noted.  In  a  severe  case  a  blistering  effect  was  wanted  ;  this  was 
obtained  easily  by  painting  the  wood  alcohol  tincture  on  thickly 
and  covering  it  with  a  piece  of  oiled  muslin.  The  burning  pain 
became  so  great  in  ten  or  fifteen  minutes  that  the  muslin  had  to  be 
taken  off  and  vaseline  applied.  From  this  experience  I  would  say 
that  the  wood  alcohol  tincture  of  iodine  is  only  fitted  for  veterinary 
practice,  or  for  cases  in  which  strong  irritating  effects  are  called  for, 
and  I  might  add  that  in  general  the  effects  of  this  tincture  were 
distinctively  less  satisfactory  in  my  cases  than  the  U.S. P.  tincture. 
Noting  that  the  peculiar  irritating  effects  seemed  to  come  from 
the  vapor  of  the  wood  alcohol  tincture,  I  sought  the  reason  for  this, 
and  I  think  it  lies  in  the  formaldehyde  and  formic  acid  formed  in 
this  tincture  by  the  action  of  iodine  on  wood  alcohol,  or  some  of  its 
impurities  ;  for  the  tincture  made  with  pure  methyl  alcohol  yielded 
much  less  pronounced  results.  One  hundred  c.c.  of  tincture  were 
made,  U.S.P.  strength,  and  allowed  to  stand  ten  days,  to  get  as 
much  action  by  the  iodine  as  possible;  this  was  then  distilled  in 
fractions  of  10  c.c.  and  each  of  these  examined.  The  distillation 
began  at  66°  C,  running  up  to  68°  for  the  last  four  fractions.  The 
first  lraction  was  of  a  light  straw  color,  contained  a  trace  of  iodine, 
reduced  silver  solutions  at  once  and  gave  marked  reactions  for 
formaldehyde  and  formic  acid.  To  make  sure  of  the  former,  a 
number  of  tests  were  applied  to  the  distillate — all  gave  very  positive 
reactions.  I  did  not  then  estimate  the  amount  of  formaldehyde 
formed  from  given  quantities  of  each  of  the  substances,  but  this  I 
