82 
VARIETIES. 
A  Test  for  Alcohol  in  Essential  Oils. — J.  J.  Bernoulli  recommends  for 
this  purpose  acetate  of  potash.  "When  to  an  ethereal  oil,  contaminated  with 
alcohol,  dry  acetate  of  potash  is  added,  this  salt  dissolves  in  the  alcohol, 
and  forms  a  solution  from  which  the  volatile  oil  separates.  If  the  oil  be 
free  from  alcohol,  this  salt  remains  dry  therein. 
Wittstein,  who  speaks  highly  of  this  test,  has  suggested  the  following 
method  of  applying  it  as  the  best : — In  a  dry  test  tube,  about  half  an  inch 
in  diameter,  and  five  or  six  inches  long,  put  not  more  than  eight  grains  of 
powdered  dry  acetate  of  potash;  then  fill  the  tube  two-thirds  full  with  the 
essential  oil  to  be  examined.  The  contents  of  the  tube  must  be  well  stirred 
with  a  glass  rod,  taking  care  not  to  allow  the  salt  to  rise  above  the  oil ; 
afterwards  set  aside  for  a  short  time.  If  the  salt  be  found  at  the  bottom  of 
the  tube  dry,  it  is  evident  that  the  oil  contains  no  spirit.  Oftentimes, 
instead  of  the  dry  salt,  beneath  the  oil  is  found  a  clear  syrupy  fluid,  which 
is  a  solution  of  the  salt  in  the  spirit,  with  which  the  oil  was  mixed.  "When 
the  oil  contains  only  a  little  spirit,  a  small  portion  of  the  solid  salt  will  be 
found  under  the  syrupy  solution.  Many  essential  oils  frequently  contain  a 
trace  of  water,  which  does  not  materially  interfere  with  this  test,  because, 
although  the  acetate  of  potash  becomes  moist  thereby,  it  still  retains  its  pul- 
verulent form. 
A  still  more  certain  result  may  be  obtained  by  distillation  in  a  water 
bath.  All  the  essential  oils  which  have  a  higher  boiling  point  than  spirit, 
remain  in  the  retort,  whilst  the  spirit  passes  into  the  receiver  with  only  a 
trace  of  the  oil,  where  the  alcohol  may  be  recognised  by  the  smell  and  taste. 
Should,  however,  a  doubt  exist,  add  to  the  distillate  a  little  acetate  of  potash 
and  strong  sulphuric  acid,  and  heat  the  mixture  in  a  test  tube  to  the  boiling 
point,  when  the  characteristic  odor  of  acetic  ether  will  be  manifest,  if  any 
alcohol  be  present. — Ibid. 
Saponaceous  Cream  of  Almonds. — (Crime  d'Amandcs  ameres.) — The  pre- 
paration sold  under  this  name  is  a  potash  soft  soap,  made  with  lard  and 
perfumed  with  essential  oil  of  almonds.  It  has  a  beautiful  pearly  appear- 
ance, and  makes  an  excellent  lather  with  a  brush,  and  has  met  with  an 
extensive  demand  as  a  shaving  soap,  especially  in  Paris.  It  is  prepared 
thus: — Take  of  fine  clarified  lard,  7  lbs;  of  potash  ley,  containing  about  26 
per  cent,  of  caustic  potash,  3  lbs.  12  oz. ;  of  rectified  spirit,  2  oz. ;  of  essen- 
tial oil  of  almonds,  2  drachms.  Melt  the  lard  in  a  porcelain  vessel,  by  a 
salt-water  bath  or  a  steam  heat  under  15  lbs.  pressure,  then  run  in  the  ley 
very  slowly,  agitating  continually  from  right  to  left  during  the  whole  time  ; 
when  about  half  the  ley  is  run  in,  the  mixture  begins  to  curdle  ;  it  will, 
however,  finally  become  so  firm  and  compact  that  it  cannot  be  stirred,  if 
the  operation  is  successful.  The  soap  is  now  finished,  but  is  not  pearly  ;  it 
will,  however,  assume  that  appearance  by  long  trituration  in  a  mortar, 
gradually  adding  the  alcohol,  in  which  is  previously  dissolved  the  perfume. 
— Annals  of  Pharmacy,  April,  1852. 
