Am.  Jour.  Pharm. 
Oct.,  1884. 
Estimation  of  Nicotine. 
503 
0*690  of  the  concrete  resin  gave  0*200  HgS,  corresponding  to  0*391 
Hgl2,  an  amount  much  larger  than  in  the  successful  experiments. 
To  20  cc.  of  B.  c.  were  at  first  added  12  cc.  of  M.  S. ;  the  crystal- 
line deep  yellow  precipitate  was  collected  on  a  tared  filter,  washed  and 
dried ;  to  the  liquid  more  M.  S.  was  added  until  it  ceased  to  give  pre- 
cipitate ;  10*4  cc.  were  required.  The  second  precipitate  was  also  col- 
lected on  a  tared  filter,  washed  and  dried,  and  from  the  liquid  the  Hg 
was  precipitated  by  H2S,  yielding  0*033  HgS. 
First  precipitate  weighed  0*482 
Second       "  "  0*353 
In  regard  to  the  circumstance  that  a  more  dilute  solution  of  nico- 
tine requires  more  M.  S.  than  one  of  a  certain  concentration,  it  is  my 
impression  that  it  is  owing  principally  to  the  formation  of  resinous 
precipitate,  which  is  more  apt  to  be  formed  in  very  dilute  solutions. 
The  resinous  precipitate  has  a  different  composition  from  the  regular 
crystalline  precipitate,  and  contains  proportionally  a  larger  amount  of 
Hgl2.  Experiments  made  with  dilute  solutions  of  A.  and  B.  showed 
that  the  more  resinous  precipitate  is  formed  the  more  M.  S.  was 
required. 
A  solution  for  testing  ought  to  contain  at  least  0*5  per  cent,  of  nico- 
tine to  obtain  correct  results. 
Louisville,  Ky.,  September,  1884. 
Menthol. — I  think  it  was  Mr.  Malcolm  Morris  who,  someHime  ago, 
spoke  of  the  antiseptic  use  of  menthol  in  ringworm  of  the  scalp.  I  applied 
a  solution  in  rectified  spirit  to  the  tinea  tonsurans  of  a  young  friend  in  the 
winter  of  1879,  and  cure  resulted  ;  and  recently  I  have  met  with  success  in 
this  disease  from  a  pomade  of  menthol,  iodoform  and  vaseline. 
In  facial  neuralgia,  in  some  forms  of  sciatica,  in  neuralgic  headache 
(clavus)  and  in  toothache,  the  most  recent  instance  being  in  a  severe  case 
of  a  lady  recovering  from  acute  alcoholism,  I  have  repeatedly  found  relief 
to  follow  within  a  few  minutes  of  its  application.  The  cones  or  sticks  are 
useful  for  external  application.  Frequently,  however,  I  use  now  the  follow- 
ing formula:  Menthol,  30  grains;  and  spirit  of  rosemary,  rectified  spirit, 
each  two  drachms  ;  or  compound  spirit  of  lavender  may  be  used  instead  of 
the  rosemary  for  application  to  the  cavity  of  a  carious  tooth.  I  have  only 
taken  it  once  internally  myself,  but  never  have  prescribed  it.  This  has, 
however,  been  done. — Brit.  Med.  Jour.;  Louisv.  Med.  News. 
