AmAprii%8?8.r,D'}  Oil  °f  Sweet  Almonds. — Impure  Magnesia.  161 
OIL  OF  SWEET  ALMONDS. 
By  C.  E.  Df.Puy,  Ph.G. 
Having  noticed,  while  preparing  unguentum  aquae  rosae,  an  almond- 
like odor,  and,  thinking  it  came  from  the  supposed  oil  of  sweet 
almonds  which  I  was  using,  it  led  me  to  an  examination  of  the  article. 
I  observed  that  the  oil  possessed  an  odor  resembling  that  of  oil  of 
bitter  almonds,  and,  that  by  heating  a  short  time,  this  odor  disappeared 
and  in  its  stead  the  oil  had  acquired  a  slightly  rancid  odor.  It  also 
soon  produced  quite  a  heavy  precipitate  of  a  white  flocculent  character. 
The  oil  congealed  at  a  temperature  of  I5°F.,  and  had  the  sp.  gr. 
0*945.  It  was  insoluble  in  ether,  soluble  in  two  volumes  of  oil  of 
turpentine  and  in  an  equal  portion  of  chloroform,  insoluble  in  cold 
alcohol  of  the  sp.  gr.  0*827,  but  soluble  m  3°  volumes  of  boiling 
alcohol  of  the  same  sp.  gr. 
Treated  with  cold  HNOs  the  oil  assumed  a  violet  tinge,  which  soon 
developed  into  a  bright  yellow  color.  But  even  after  long  standing  it 
neither  became  hard  or  emulsionized.  The  action  of  HN02  fully 
coroborated  this  test  in  neither  solidifying  the  oil  nor  separating  crys- 
talline particles  of  elaidin,  thus  proving  it  to  be  a  drying  oil,  while,  on 
the  contrary,  the  true  oil  of  almonds  belongs  to  the  class  of  none- 
drying  oils. 
Heated  with  HNOs  the  oil  at  first  changed  to  a  dark-yellow  and 
finally  to  a  reddish-brown  color. 
With  H2S04  the  oil  at  first  assumed  a  bright  yellow  color,  which 
gradually  changed  to  a  dark  purple,  a  test  which,  as  well  as  the  previous 
one  with  cold  HN03,  would  particularly  indicate  the  presence  of  large 
quantities  of  poppy  seed  oil,  while  the  reaction  obtained  by  heating 
with  HNO3  would  indicate  probable  admixture  (though  I  think  in  a 
small  degree)  of  the  oil  obtained  from  either  the  peach  or  apricot 
kernel,  which,  if  present,  might  furnish  the  almond-like  odora  first 
noticed. 
Chelsea,  Mich.,  March  Sth,  1878. 
IMPURE  MAGNESIA. 
By  H.  C.  Archibald  Ph.G. 
In  the  course  of  ordinary  business,  I  had  occasion  to  order  from  a 
wholesale  druggist  some  heavy  oxide  of  magnesium,  for  which  there  is 
