ON  ACONITIA  AND  ITS  PHYSIOLOGICAL  EFFECTS.  311 
and  winch,  after  three  successive  crystallizations  and  evidently 
chemically  pure,  determined  the  same  symptoms  as  amorphous 
aconiiia,  though  in  a  much  weaker  degree.  What  is  the  nature 
of  this  substance  which  has  been  obtained  by  Mr.  Morson,  and 
for  which  he  proposes  the  name  of  napeliina  ?  Is  it  a  transfor- 
mation of  aconitia,  or  a  co-extstant  body?  Whatever  it  be,  M. 
Hottot  has  studied  aconitia,  which  presents  the  following  pro- 
perties : 
Aconitia  blues  reddened  litmus  paper,  saturates  acid3  and 
forms  salts  which  do  not  crystallize.  It  is  a  nitrogenous  alka- 
loid, of  which,  the  composition,  according  to  M.  Stahlschmidt, 
is  represented  by  C60  H17  Ou  N.  Treated  hot  by  S03,  HO,  it 
is  colored  first  yellow,  and  afterwards  violet  red  ;  tannin  pre- 
cipitates it  abundantly;  ioduretted  iodide  of  potassium  a  kermes 
colored  precipitate,  and  this  reagent  is  its  best  antidote.  Iodo- 
foydrargyrate  of  potassium  gives  a  curdy  yellowish-white  precipi- 
tate ;  chloride  of  gold,  yellow,  and  with  chloride  of  piatinum 
no  precipitate. 
M.  Hottot  employs  aconitia  in  the  form  of  pills,  each  con- 
taining the  fifth  of  a  milligramme  (^sth  grain)  or  in  the  form 
of  tincture  one  sixteenth  of  a  grain  to- the  drachm.  The  dose 
of  the  pills  is  from  2  to  10  per  day,  and  of  the  tincture  10  to 
40  drops. 
The  author  has  arrived  at  the  following  conclusions  as  to 
the  physiological  action  of  aconitia  : 
The  root  of  aconite  only  should  be  used  for  making  the  pre- 
parations of  aconite. 
Aconitia  has  the  same  physiological  properties  as  the  root. 
The  irritant  properties  of  aconite,  usually  attributed  to  an  acrid 
principle,  belongs  to  aconitia.  Its  action  is  exercised  on  the 
mucous  membranes. 
The  absorption  of  aconitia  by  the  intestinal  canal  is  more 
rapid  than  is  that  of  curara  and  strychnia  by  the  s:ime  tissue, 
and  this  explains  the  rapidity  of  the  death  of  animals  to  which 
even  small  doses  of  aconitia  have  been  given. 
Aconitia  acts  on  the  nervous  centres  and  successively  on  the 
bulb,  the  spinal  marrow,  and  the  brain. 
The  symptoms  manifest  themselves  in  the  following  order : 
