AmsJeptr;i889arm'}         Notes  from  Various  Journals.  469 
alcoholic  solution  of  resorcin,  a  violet  color,  rapidly  changing  to  yel- 
low, is  produced.  On  warming  or  adding  excess  of  the  reagent  the 
liquid  gets  dark  brown.  One  part  of  resorcin  dissolved  in  10,000 
parts  of  water  will  still  show  the  reaction.  Carbolic,  salicylic,  ben- 
zoic and  other  allied  acids  do  not  show  the  reaction,  and  at  the  roost 
turn  only  slightly  yellow  on  warming.  Pyrocatechin,  when  treated 
with  the  reagent,  turns  a  vanishing  green ;  hydroquinone  soon  gets 
yellow  or  red.  Another  test  is  to  first  add  a  little  liquor  ammonise 
and  then  a  few  drops  of  the  hypochlorite,  when  the  liquid  will  give  a 
reddish  violet  color,  which  changes  green  on  boiling.  The  coloring 
matter  is  not  taken  up  by  benzol.  The  reaction  is  not  shared  by 
salicylic  acid,  benzoic  acid  or  antifebrin,  but  carbolic  acid  thus  treated 
turns  a  greenish  blue,  which  is  partly  decomposed  by  benzol.  The 
colors  are  changed  to  red  by  dilute  sulphuric  acid. — H.  Bodde,  Nederl. 
Zydschr.  v.  Pharmacie  ;  reprint  from  The  Analyst. 
Dextrin  Substitute  for  Gum  Arabic. — A.  Schumann  has  been  granted 
patents  in  Germany  for  a  process  of  manufacturing  dextrin  free  from 
sugar  as  a  substitute  for  gum  arabic.  Starch  is  mixed  to  a  thick 
cream  with  cold  water  and  treated  with  one  per  cent,  of  mineral  acid. 
After  24  hours  the  mixture  is  washed  until  free  from  acid.  The 
starch  is  again  mixed  with  water  to  a  cream  and  heated  to  160-170°C. 
by  superheated  steam  until  all  the  starch  is  converted.  This  solution 
is  refined  and  evaporated  to  dryness. 
The  active  principle  of  Strophanthus  glaber. — M.  Arnaud  in  Compt. 
rend,  described  recently  two  crystallized  substances,  ouabain,  C30H46O12, 
obtained  from  the  wood  of  Aconkaihera  Ouabaio,  and  strophanthin 
C31H48012,  from  the  seeds  of  Strophanthus  Kombe.  He  has  since  exa- 
mined the  crystallized  substance  contained  in  the  seeds  of  Strophan- 
thus glaber  of  Gabon,  which  furnish  the  arrow-poison  of  the  Pahonin 
tribe.  This  principle  appears  to  be  identical  with  ouabain,  which  ex- 
hibits toxic  effects  almost  identical  with  strophanthin.  Hardy  and 
Galois  have  also  described  a  crystallized  substance  from  Strophanthus 
glaber,  but  imperfectly  for  want  of  material.  These  substances  are 
glucosides,  and  low  temperatures  must  be  adhered  to  in  the  extraction 
in  order  to  avoid  decomposition.  The  crystals  of  the  glucoside  from 
the  seeds  of  strophanthus  glaber  (which  gave  the  remarkably  high 
yield  of  4#7  per  cent.)  are  transparent,  very  slender,  and  of  rectangular 
form ;  by  slow  crystallization  they  are  thicker  and  become  opaque. 
The  melting  point  is  about  185°  O,  but  a  pasty  condition  obscures 
