THE  ESSENTIAL  OIL  OF  BITTER  ALMONDS. 
347 
No  effect  was  produced  for  twenty  minutes ;  it  looked  a  little 
dull,  but  revived  shortly,  and  remained  quite  well  for  four  hours 
and  a  half,  during  which  it  was  under  examination,  but  it  died 
in  the  course  of  the  night. 
With  the  urine  of  these  rabits  Dr.  Maclagan  was  enabled  to 
confirm  the  observation  of  Wohler  and  Frerichs,  that  the  oil  in 
its  passage  through  the  system  was  converted  into  hippuric  acid, 
and  if  administered  in  a  large  quantity,  partly  passed  unchanged 
into  the  urine. 
To  contrast  the  action  of  the  oil  on  rabbits  with  that  of  other 
volatile  oils,  the  author  made  some  further  experiments.  of 
oil  of  carraway  on  a  dog  produced  no  other  effect  than  slight 
vomiting,  z].  of  oil  of  cloves  on  a  rabbit  the  animal  fell  mo- 
tionless on  its  side  in  fifteen  minutes,  and  died  in  an  hour  and  a 
quarter.  The  symptoms  were  essentially  the  same  as  those  pro- 
duced by  the  rectified  oil  of  bitter  almonds,  though  the  fatal  re- 
sult was  not  so  speedy. 
Dr.  Maclagan  summed  up  the  evidence  afforded  by  the  experi- 
ments of  others  by  stating  the  following  conclusions  to  which  he 
had  been  led. 
1.  That  the  marked  difference  between  rectified  and  unrecti- 
fied  oil  shows  that  the  poisonous  action  of  the  latter  is  essen- 
tially due  to  the  hydrocyanic  acid  which  it  contains. 
2.  That  the  oil  really  free  from  hydrocyanic  acid,  in  doses  of 
a  few  drops,  does  not  act  as  a  poison  on  animals  generally  ;  and 
that  the  instances  of  fatal  effect  on  man  and  animals  from  such 
doses  of  unrectified  oil  must  be  referred  entirely  to  the  hydro- 
cyanic acid. 
3.  That  experiments  on  rabbits  with  quantities  of  half-a- 
drachm  and  under,  invariably  show  that  if  quite  free  from  prus- 
sic  acid,  such  doses  do  not  cause  fatal  effects.  But  in  larger 
doses  [a  drachm  and  upwards]  it  does,  even  when  quite  free  from 
hydrocyanic  acid,  prove  fatal  to  rabbits,  but  with  great  variation 
in  respect  to  the  rapidity  of  the  death,  which  variation  is  due  to 
the  physiological  peculiarities  of  these  animals. 
4.  That  in  dogs,  whose  organization  renders  them  much  better 
subjects  for  testing  the  probable  effects  of  the  substance  on  man, 
dose  seven  so  large  as  three  drachms  of  the  oil,  nearly  or  entirely 
free  from  prussic  acid,  produce  no  other  affect  than  a  little  vom- 
iting, and  do  not  cause  death  or  even  dangerous  symptoms. 
