Am.  Jour.  Pharm.  ) 
Sept.,  1885.  / 
Menthol, 
429 
MENTHOL. 
Brief  Abstracts  from  Theses. 
Elmer  B.  Kyle,  Ph.  G.  mentions  the  following  among  the  properties 
of  menthol.  When  thrown  upon  water  currents  are  produced  to  and 
from  the  dissolving  crystals,  similar  to  the  motions  observed  under  the 
same  condition  with  camphor.  Menthol  liquefies  with  chloral,  thymol 
and  camphor,  and  this  action  is  particularly  noticeable  with  thymol, 
crystals  of  the  two  substances,  placed  in  contact,  being  in  a  few  minutes 
transformed  into  a  thick  oily  liquid.  On  gently  heating  a  mixture  of 
one  drachm  of  the  aqueous  solution  of  menthol  with  half  a  drachm 
of  a  solution  of  one  grain  iodine  and  five  grains  potassium  iodide  in 
two  drachms  of  water  with  a  small  quantity  of  polassa  solution,  the 
characteristic  odor  of  iodoform  is  observed.  The  aqueous  solution  is 
not  disturbed  by  ferric  chloride  or  bromine  water,  but  yields  a  slight 
turbidity  with  chlorine  water.  One  grain  of  menthol  yields,  with  120 
drops  of  sulphuric  acid,  a  brownish-red  liquid  of  a  very  disagreeable 
odor,  and  on  the  addition  of  a  little  potassium  bichromate  becomes 
chrome-green,  the  color  remaining  unalterei  for  several  weeks.  Men- 
thol slightly  warmed  with  nitric  acid  yields  a  thick  wine  colored  oily 
liquid,  and  at  a  higher  heat  red  fumes  are  given  off ;  on  neutralizing 
now  with  ammonia,  a  precipitate  was  observed,  which  was  soluble  in 
alcohol,  the  solution,  when  evaporated  yielding  an  indistinctly  crystal- 
line mass. 
Frank  T.  Landis,  Ph.  G.,  gives  a  history  of  the  preparation  of  the 
oil  and  of  menthol  in  Japan,  and  of  the  chemical  and  medical  pro- 
perties of  menthol. 
Wm.  J.  Laval,  Ph.G.,  examined  two  samples  of  Japanese  men- 
thol and  one  of  pipmenthol,  and  found  them  to  differ  mainly 
in  the  fusing  point  which  for  the  latter  was  40°  C  and  for  the 
two  other  specimens  35°  and  36'5°C.  The  specific  gravity  was 
•9002  and  '9004,  and  for  pipmenthol  '9003.  At  39°  C.  1  Gm.  of 
alcohol  dissolved  8*327  Gm.  of  menthol,  and  20  Gm.  of  water  took 
up  '031  Gm.  of  menthol.  This  is  insoluble  in  hydrochloric  acid,  not 
affected  by  alkalies,  sparingly  soluble  in  glycerin,  somewhat  soluble  in 
warm  acetic  acid,  decomposed  on  being  heated  with  nitric  acid,  the 
mint  odor  disappearing  almost  entirely,  and  under  the  infiuence 
of  hot  sulphuric  acid  is  changed  into  a  dark  brown  or  black  liquid. 
