198 
Gleanings  in  Materia  Medica. 
f  Am  Jour  I'liarm. 
t      April,  1883. 
reported  on  a  blue  oil  from  the  so-called  aromatic  Peruvian  guaiac 
resin,  and  on  blue  fractions  from  oil  of  valerian;  and  Fllickiger 
(^^  Phar.  Chemie/^  p.  309)  on  blue  oils  from  sumbul,  puchury, 
patchouly  and  asafoetida.  Hock  finds  that  all  these  blue  oils  show  in 
the  spectroscope  three  absorption  bands  in  red  and  orange ;  they  distil 
at  260°  C.  and  give  a  colorless  vapor,  not  blue  as  was  stated  by  Kach- 
ler  (1871),  for  oils  of  galbanum  and  German  chamomile.  Though 
the  blue  compound  seems  to  pre-exist  occasionally  in  the  plant,  Hock 
regards  it  as  being  mostly  produced  by  decomposition  at  an  elevated 
temperature.  Old  resinified  oils  were  found  to  yield  a  larger  amount 
of  the  blue  product,  Avliich,  in  contact  with  air  is  easily  altered,  turn- 
ing to  dingy  brown. — Archiv  d.  Fhar.,  Jan.  1883,  pp.  17,  18. 
Composition  of  Cacao  Butter. — Kingzett  announced  in  1877  the  iso- 
lation of  two  fatty  acids  having  the  melting  points  57°  and  72°C. ;  the 
latter  was  named  theobromic  acid,  and  was  stated  to  have  the  formula, 
^6J^m^2'  Vander  Becke  in  1880  endeavored  to  prepare  the  latter, 
but  without  success.  The  subject  was  recently  investigated  by  M.  C. 
Traub,  who  examined  five  samples  of  oil  of  theobroma,  two  of  which 
had  been  prepared  by  himself.  After  saponification  the  acids  were 
ascertained  to  be  completely  ])recipitated  by  magnesium  acetate,  and  by 
repeated  fractional  precipitation  it  was  proven  that  the  oil  consists  of  the 
glvceryl  esters  of  oleic,  lauric,  palmitic,  stearic  and  arachic  acids,  and 
that  the  solid  consistence  of  the  oil  and  its  low  melting  point  are  most 
likely  due  to,  the  peculiar  proportions  in  which  these  compounds  are 
combined  resembling  in  this  respect  the  behavior  of  certain  metals. — 
Archiv  d.  Fhar.,Jm.,  1883,  pp.  19—23. 
Free  Acids  in  Vegetable  Fats. — Ernst  Schmidt  and  H.  Roemer 
obtained  from  coeculus  indicus  23'6  per  cent,  fat,  of  which  39  per  cent. 
(0-2  per  cent,  of  the  fruit)  proved  to  be  stearic  acid,  which  was  obtained 
by  dissolving  the  oil  in  hot  alcohol,  precipitating  with  barium  acetate, 
exhausting  the  precipitate  with  petroleum  benzin,  and  decomposing 
the  barium  salt  with  hydrochloric  acid. 
By  fractional  distillation,  in  vacuo,  of  commercial  expressed  oil  of 
nutmegs  myristic  and  stearic  acids  were  obtained,  amounting  to  3  or  4 
per  cent.,  the  last-named  acid  being  present  in  small  quantity. 
A  very  small  proportion  of  free  acid  is  contained  in  laurel  oil,  the 
expressed  fat  of  the  fruit  of  Laurus  nobilis ;  but  by  exhausting  the 
fruit  with  hot  alcohol  2  to  3  per  cent,  of  fatty  acid  was  obtained, 
