Cherry  Laurel, 
J  Am.  Jour.  Pharm. 
(      June,  1880. 
'each  case  the  first  portions  of  the  distilled  liquid  were  tried  for  hydro- 
cyanic acid  with  the  usual  tests,  viz.,  sulphate  of  copper  and  guaiac, 
the  production  of  sulphocyanate  and  that  of  Prussian  blue.  No  trace 
of  hydrocyanic  acid  was  proved  to  be  present  by  these  means.  Another 
distillation,  like  the  former,  also  performed  by  using  the  leaves  minutely 
cut,  was  carried  on  for  an  hour  or  two,  so  as  to  afford  a  large  quantity 
■of  water,  say  about  gallon.  It  had  nearly  the  usual  odor  of  cherry- 
laurel  water,  yet  no  essential  oil  made  its  appearance.  The  whole 
quantity  of  the  distilled  water  was  now  repeatedly  shaken  with  ether  \ 
from  the  ethereal  layers  afterwards  the  ether  was  cautiously  distilled  off 
and  the  residue  exposed  to  spontaneous  evaporation  at  a  temperature 
not  exceeding  20°C.  (68°F.),  It  afforded  about  \\  gram  of  an  oily 
liquid  reminding,  not  exactly  of  cherry-laurel  oil,  but  a  little  suggestive 
of  acetic  or  similar  compound  ethers,  and  displaying  at  the  same  time 
a  certain  pungency  ;  it  was  of  a  decidedly  acid  reaction.  Supposing  it 
to  be  (impure)  cherry-laurel  oil,  I  thought  it  quite  in  accordance  that 
small  crystals  began  to  be  formed  on  the  sides  of  the  phial.  To  inves- 
tigate the  nature  of  the  essential  oil  I  shook  it  with  a  saturated  solution 
of  bisulphite  of  potassium,  SO3KH,  after  having  ascertained  that  this 
solution  immediately  combined  with  true  benzylic  aldehyd,  /.  essen- 
tial oil  of  laurocerasus,  yielding  crystallized  scales  of  the  compound 
CgH5.COH,S03KH.  But  such  was  by  no  means  the  case  with  the 
oily  liquid  which  had  been  extracted  from  the  water.  And  as  to  the 
small  crystals  which  had  separated  from  the  same  oily  liquid,  they 
proved  not  to  be  benzoic  acid  inasmuch  as  they  readily  melted  at  about 
6o°C.  (i40°F.).  Nor  was  it  possible  to  ascertain  the  cause  of  the 
acid  reaction  of  the  oily  liquid  ;  it  was  due  neither  to  formic  acid  nor 
to  any  other  acid  of  the  fatty  series.  The  aqueous  residue  in  the  still 
was  duly  concentrated  and  found  to  be  very  rich  in  mucilage  and 
uncrystallizable  sugar. 
These  experiments,  which  were  for  the  most  part  performed  by  Mr. 
Fels,  a  pupil  of  mine,  show  that  the  source  of  hydrocyanic  acid  and 
benzylic  aldehyd  in  the  laurel  leaves  is  destroyed  by  intense  cold.  A 
minute  quantity  of  an  essential  oil  is  still  afforded  by  the  leaves,  but  it 
does  not  agree  with  the  oil  as  yielded  by  the  living  plant.  Dried  leaves 
are  sometimes  said  likewise  to  yield  no  longer  any  hydrocyanic  acid  ; 
I  am  not  able  to  confirm  this  statement,  having  ascertained  that  fresh 
cherry-laurel  leaves,  which  I  dried  for  several  days  at  the  temperature 
