606  Gleanings  from  Foreign  Journals.        { ^"''DeT^Sr"^"""' 
The  benzin  odor  of  old  syrup  of  tolu  is  attributed  to  the  action  of  the 
calcium  salts  of  ordinary  water  on  the  balsam  of  tolu  at  a  higher  tem- 
perature. M.  Labre  bases  his  observation  on  Mitscherlich's  synthesis 
of  benzin,  i.  e.,  distilling  benzoate  of  calcium  with  quick  lime,  thus 
forming  carbonate  of  calcium  and  benzin,  C,4Hg04-{-2CaO=2(CaO,C02) 
-f-CigHg.  Syriip  of  tolu  made  with  distilled  water  does  not  acquire  a 
benzin  odor  on  standing. — Repert.  de  Phar.,  Oct.,  1885,  p.  438. 
Papaverine. — Dr.  Guido  Goldschmiedt  states  that  the  formula  of 
papaverine  as  given  by  Hesse  (C2iH2iN04)  is  incorrect.  He  proved 
by  a  number  of  experiments  that  the  formula  as  originally  given  by 
Merck  (C20H21NO4)  is  correct. — Pharmac.  Post,  xviii,  p.  1077. 
To  Detect  Gamboge  in  Mixtures,  etc. — Solutions  containing  gamboge 
are  mixed  with  powdered  glass,  evaporated  to  dryness,  powdered,  and 
treated  with  benzin.  If  the  benzin  solution  is  colorless  it  is  again 
shaken  with  the  powder  and  sufficient  hydrochloric  acid  to  make  the 
solution  decidedly  acid.  Benzin  does  not  dissolve  gamboge  in  presence 
of  soap.  If  after  treating  with  benzin  and  acid  the  benzin  solution 
is  colorless,  no  gamboge  is  present.  If,  however,  the  solution  has  a 
yellow  cast,  it  is  filtered  and  tested  as  follows :  To  a  small  portion  of 
the  filtrate  is  added  a  dilute  solution  of  caustic  soda;  if  a  red  colora- 
tion is  produced,  gaseous  ammonia  is  led  into  the  remaining  solution 
until  it  is  saturated.  The  flakes  which  separate  out  are  collected  on  a 
filter  and  washed  with  benzin  before  dissolving  them  in  alcohol.  This 
solution  treated  with  an  alcoholic  solution  of  ferric  chloride  turns 
black,  and  on  adding  caustic  soda  the  color  changes  from  black  to 
dark  yellow,  but  never  red,  if  gamboge  is  present.  By  this  method 
Hirschsohn  was  able  to  detect  0*01  gram  of  gamboge. — Phar.  Zeit.f. 
RussL,  xxiv,  p.  609. 
Impurities  in  Ether. — Boerrigter  confirms  the  statement  of  other 
authors  that  ether  frequently  contains  hydrogen  peroxide  and  alde- 
hyde. Ether  should  be  kept  in  dry,  tightly  corked  bottles.  The 
ozone  produced  by  the  evaporation  of  ether,  if  water  is  present,  con- 
verts it  into  hydrogen  peroxide.  Pure  ether  is  not  discolored  by  caus- 
tic potash,  nor  is  alcohol  affected  by  it  unless  air  has  access,  when  pos- 
sibly aldehyde  is  formed. — Phar.  Zeit.f.  RussL,  xxiv,  p.  584. 
Digitalin,  Digitalein  and  Digitin. — Digitalis  is  exhausted  with  water 
and  the  infusion  is  decolorized  with  animal  charcoal,  treated  with  ace- 
tate of  lead  and  filtered.  The  filtrate  is  then  treated  with  a  mixture 
of  12  parts  of  liquor  plumbi  subacetatis  and  1  part  of  spirit  of  ammo- 
