224  Gleanings  from  the  German  Journals.  {AmMay?i§3arm' 
young  trees,  Sty  rax  Benzoin,  Dryand.  To  aid  this  examination 
authentic  Sumatra  benzoin  was  first  investigated.  Contrary  to  the 
published  statements  it  was  found  that  benzoin  was  entirely,  although 
somewhat  slowly,  soluble  in  ether.  By  agitating  this  solution  with 
4  per  cent,  solution  of  soda  until  neutral  reaction  resulted,  separat- 
ing the  ethereal  layer  and  carefully  evaporating  it,  an  oily  residue 
was  obtained^  in  which  traces  of  styrol,  benzol  and  benzaldehyde, 
2-3  per  cent,  styracin  and  about  I  per  cent,  phenylpropyl  cinna- 
mate  were  found.  From  the  sodium  hydrate  solution,  vanillin, 
benzoic  and  cinnamic  acids  and  the  three  resins  were  isolated, 
y'-resin  soluble  in  sodium  carbonate  solution;  the  part  insoluble, 
treated  with  ether,  was  again  separated,  a-resin  dissolving  while 
ft- resin  remained  insoluble.  Prolonged  boiling  of  a-  and  ^-resins  with 
sodium  carbonate  solution  caused  them  to  change  into  ^-resin  ;  this 
again  by  boiling  with  potassium  hydrate  solution  was  decomposed, 
cinnamic  acid  and  two  alcohols  resulting ;  white  crystallizable  ben- 
zoresinol,  C16H2604  (present  in  small  quantity  only),  and  amorphous 
brown  resinotannol,  C18H20O4.  The  three  resins  of  previous  investi- 
gators making  up  the  larger  part  of  benzoin,  therefore  are  mixtures 
of  the  more  or  less  decomposed  esters  of  cinnamic  acid  with  these 
two  alcohols.  Besides  free  benzoic  acid  there  is  also  present  a  quan- 
tity of  free  cinnamic  acid.  The  bark  of  the  uninjured  trees  by 
analysis  contained  traces  of  wax,  small  quantities  of  phloroglucin 
and  sugar  and  large  quantities  of  a  tannin  easily  oxidized  to  a 
phlobaphen  (benzophlobaphen)  having  the  formula  C51H50O21.  As 
the  uninjured  bark  contains  neither  secretion  nor  secretion-cells,  but 
does  contain  large  quantities  of  tannin,  and  as  the  balsam  contains  a 
large  quantity  of  resinotannol  (an  alcohol  reacting  like  a  tannin)  and 
the  balsam  formation  first  takes  place  in  the  parts  of  the  bark  con- 
taining the  tannin,  it  is  very  probable  that  benzoin  balsam  is  pro- 
duced from  the  tannin  of  the  bark. — Fritz  Ludy,  Arch,  der  Pharm., 
1893,43-95- 
Sumatra  benzoin. — Professor  E.  Schmidt,  supplemental  to  the  pre- 
vious article,  gives  some  results  of  an  elaborate  examination  made 
by  C.  Denner  some  years  ago,  but  of  which  no  complete  statement 
ever  appeared  in  print.  He  isolated  free  benzoic  cinnamic  acids , 
styrol,  vanillin,  benzaldehyde,  styracin,  benzyl  cinnamate,  and  three 
so-called  benzoresins  ;  the  styrol  and  benzaldehyde  were  obtained  in 
much  larger  quantity  than  by  Ludy  so  that  they  could  be  identified 
