SYRUP  OF  LACTUCARIUM. 
515 
mouth  covered  with  a  slip  of  glass  moistened  on  the  under  side 
with  nitrate  of  silver  in  solution.  In  a  short  time,  the  solution 
was  observed  to  become  opake  and  white.  This  white  film  was 
treated  with  N05,  without  effect ;  but  cyanide  of  potassium  imme- 
diately dissolved  it. 
The  mouth  of  the  vial  was  now  covered  with  another  piece  of 
glass  moistened  with  NH4  3,  HS.  After  some  minutes  the  glass 
was  removed,  and  the  moisture,  now  milky,  gently  evaporated. 
To  the  dried  residue  a  solution  of  a  persulphate  of  iron  was  applied 
by  means  of  a  glass  rod  drawn  over  the  surface.  The  modena 
red  streaks  which  appeared,  confirmed  the  former  results  with 
Ag  N05,  and  left  no  doubt  of  the  presence  of  hydrocyanic  acid. 
As  further  evidence,  however,  of  the  existence  of  HCy  in  the 
fluid,  T  added  to  the  filtrate,  (about  ounce  of  it,)  solution  of 
Ag  N05,  till  all  precipitation  ceased.  The  precipitate  was  collected 
and  washed;  and  N05  added.  By  this  means  the  carbonate  of 
silver,  &c.  were  removed.  The  undissolved  residue  was  washed, 
and  was  found  to  be  soluble  in  cyanide  of  potassium  ;  and  to  be 
decomposed  by  HC1  with  liberation  of  the  prussic  acid  odor. 
This  was  the  extent  of  my  analysis.  The  reader  must  judge  for 
himself  whether  I  found  sufficient  cause  for  the  alarming  symptoms 
manifested  by  the  patient.  He  took  no  more  of  the  medicine. 
More  than  a  month  has  elapsed  since  the  attack,  and  there  has 
been  no  return  of  the  symptoms. 
Judging  from  the  presence  of  HCy  in  the  fumes  over  the  soap 
kettle,  and  in  the  odor  of  crude  potash,  I  suspect  it  will  be  found, 
that  with  moisture,  potash  and  carbonate  of  potash  by  their  re- 
action on  organic  matter,  generally  generate  this  dangerous 
remedial  agent. 
SYRUP  OF  LACTUCARIUM. 
By  Thomas  S.  Wiegand. 
The  importance  of  Lactucarium  as  an  article  of  the  Materia 
Medica,  has  long  been  acknowledged  by  many  of  the  most  authori- 
tative writers  upon  medicine,  being  regarded  by  them  as  particu- 
larly suitable  to  the  case  of  those  whose  idiosyncrasy  forbids  the 
employment  of  opium,  or  any  of  the  opiate  products. 
From  the  experiments  of  M.  Emile  Mouchon,  detailed  in  the 
