^"™sepri88r"^'}  Experiments  on  Thymol  and  Carbolic  Acid.  459' 
COMPARATIVE  EXPERIMENTS  ON  THE  BEHAVIOR 
OF  THYMOL  AND  CARBOLIC  ACID  TOAYARDS  CER- 
TAIN REAGENTS. 
By  Edward  Hirschsohn,  Mag.  Pharm.,  Dorpat, 
In  the  preparation  of  bandages  impregnated  with  thymol  and  its 
solutions  it  often  becomes  a  question  how  definitely  to  determine  the 
presence  of  thymol  in  aqueous  solutions. 
In  the  literature  of  the  subject  accessible  to  me  I  could  find  no 
information,  and  consequently  I  instituted  a  series  of  experiments,  -the 
results  of  which  I  purpose  giving  in  the  following  paper. 
In  these  experiments  I  used  a  solution  of  thymol  prepared  in  the 
following  manner :  One  part  of  commercial  thymol  was  put  into  a 
stoppered  bottle  with  1,000  parts  of  water  at  60°  to  70°C.,  shaken 
until  completely  dissolved,  and  cooled.  The  solution  of  carbolic  acid^, 
also  in  water,  was  of  the  same  strength. 
L  MiLLON^s  Reagent.^ 
In  this  experiment  2  drops  of  the  reagent  were  added  to  5  cc.  of 
the  solutions,  and  the  whole  heated  to  the  boiling  point. 
a.  Experiments  with  Thymol :  1  to  1 ,000  :  turbid  by  boiling,  becom- 
ing clear  and  reddish- violet  in  color ;  on  cooling  again  turbid. 
1  to  2,000 :  the  same  as  the  previous  experiment,  but  color  paler. 
1  to  4,000  :  same  as  the  two  former,  but  the  mixture  remained  clear.. 
1  to  8,000  :  pale  rose  and  clear. 
1  to  1 6,000 :  very  pale  red  and  clear. 
1  to  32,000  :  no  perceptible  reaction. 
h.  Experiments  with  Carbolic  Acid :  In  all  these  experiments  the 
mixture,  on  boiling,  showed  a  more  or  less  intense  red  color,  depend- 
ing on  the  degree  of  concentration,  the  same  as  had  been  previously 
observed  by  Almen.^  From  these  experiments  it  results  that  Millon^s 
reagent  gives  with  thymol  only  a  pale  coloration,  and  in  a  dilute  solu- 
tion of  1  to  16,000  the  reaction  is  very  weak,  whilst  carbolic  acid,, 
according  to  Almen,  can  be  recognized  even  in  a  dilute  solution  of  1 
to  2,000,000. 
2.  Hypochlorite  of  Lime  and  Ammonia. 
To  5  cc.  of  solution  4  drops  of  ammonia  were  added,  and  then  1 
drop  of  a  chloride  of  lime  solution  (1  to  3),  and  the  whole  warmed. 
^  Neubauer  und  Vogel,  "Analyse  des  Harns,"  Weisbaden,  1876,  p.  70. 
^  "  Archiv  der  Pharmacie,"  3d  series,  vol.  x,  p.  53. 
