AmMa°y,r^7h7arm'}    Adulterations  in  Oleum  Theobromx.  237 
ON   DETECTION   OF   ADULTERATIONS   IN  OLEUM 
THEOBROMINE. 
By  Edward  Lamhofer,  Ph.G. 
{Abstract  from  an  Inaugural  Essay.) 
As  the  purity  of  some  of  the  commercial  samples  of  cacao-butter  has 
lately  been  suspected,  I  have  made,  at  the  suggestion  and  under  the 
direction  of  Prof.  Maisch,  an  investigation  of  the  article,  with  a  view 
of  ascertaining  its  fusing  point,  adulterations  and  mode  of  detection.  My 
first  object  was  to  procure  an  oil  of  doubtless  purity,  which  I  could  use 
as  a  standard  in  my  researches.  This  I  obtained  by  packing  the  finely- 
ground  seeds  of  the  principal  commercial  varieties  of  cacao  into  a  long 
conical  percolator,  and  extracting  the  fat  by  means  of  petroleum-benzin. 
The  benzin  was  then  removed  by  spontaneous  evaporation,  and  the  oil 
purified  by  melting  it  and  filtering,  while  hot,  through  paper.  The 
yield  of  oil  by  this  process  varied  from  38  to  51  per  cent.,  viz.  : 
Guayaquil,  46  per  cent.;  Carracas,  38  per  cent.;  San  Blass,  45  per  cent., 
and  Balli,  51  per  cent. 
Guayaquil,  Carracas,  San  Blass  and  Maracaibo  are  generally  used  here 
in  the  manufacture  of  chocolate,  and  it  is  from  these  varieties  that  we 
obtain  our  commercial  oil.  The  species  called  "  Balli "  is  from  the 
small  island  (Balli)  east  of  Java,  and  was  obtained  from  the  Dutch 
Department  of  the  Centennial  Exposition.  In  order  to  ascertain  the 
fusing  point,  the  oil  was  melted  and  drawn  up  in  capillary  tubes  of  the 
thickness  of  a  knitting  needle,  and  about  one  and  a  half  inch  in  length. 
To  get  the  oil  completely  congealed  and  hardened,  the  tubes  were  ex- 
posed to  a  freezing  temperature  for  several  days.  As  it  was  my  in- 
tention to  ascertain  if  and  in  what  measure  the  fusing  point  could  be 
used  as  a  criterion  for  the  purity  of  the  oil,  I  tried  also  several  com- 
mercial samples  and  samples  which  1  adulterated  with  mutton-  and 
beef-suet.  The  results  were  as  follows  :  Guayaquil  melted  at  gi°F.  ; 
Carracas  at  91*5°;  San  Blass  at  900;  Balli  at  89*5°;  commercial  sam- 
ple A  at  900;  commercial  sample  B  at  91*5°;  Carracas  contaminated 
with  5  per  cent,  mutton  suet  at  91*5°;  Carracas  with  5  per  cent,  beef 
suet  at  910,  and  Carracas  with  20  per  cent,  beef  suet  at  850. 
The  fusing  point  varies  between  890  and  9i*5°F.  The  British 
"  Pharmacopoeia  "  and  some  standard  works  in  this  country  place  the 
fusing  point  erroneously  at  I22°F.  I  came  to  the  conclusion  that  the 
fusing  point,  as  a  means  for  determining  any  adulteration  of  the  oil, 
