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442  GLEANINGS  FROM  THE  GERMAN  JOURNALS. 
hours,  or  to  collect  the  same  and  forward  them  to  me  that  I  may 
do  so,  but  as  jet  have  received  no  answer. — London  Pharm. 
Jour.,  May  1,  1860. 
GLEANINGS  FROM  ANNALEN  DER  CIIEMIE  UND  PHARM  AO  IE. 
By  John  M.  Maisch.  t 
Behaviour  of  Sesquisalts  of  Iron  to  Sulphurous  and  Hypo- 
sulphurous  Acid. — Hugo  Schiff  confirms  the  observations  of 
Phillips  and  Schonbein,  that  sesquisalts  of  iron  are  rendered 
darker  or  red  by  S02.  Sulphocyanide  of  iron — less  readily  a 
mixture  of  sesquichloride  of  iron  and  sulphocyanide  of  sodium — 
is  decolorized,  without  being  previously  darkened  ;  previous  di- 
gestion of  S02  with  zinc,  causes  an  instantaneous  decolorization, 
likewise  a  solution  of  hyposulphite  of  soda.  Lenz's  observation, 
that  other  salts  of  Fe2  03  are  for  a  short  time  colored  violet  by 
NaO,S202,  is  correct;  it  is  only  after  several  hours,  that  sul- 
phur is  separated,  probably  the  result  of  a  secondary  reaction. 
(Vol.  cxi.  366,  367.) 
An  alcoholic  solution  of  Biniodide  of  Mercury  continues,  even 
after  15  months,  to  be  precipitated  by  water  in  the  yellow 
modification  of  the  iodide.  H.  SchifF  remarks  that  on  the 
addition  of  water,  the  solution  turns  milky  and  separates,  after 
several  hours,  tabular  rhombic  crystals,  showing  by  polarization 
under  the  microscope  beautiful  spectra,  which  are  not  observed 
with  the  red  crystals — (Vol.  cxi.  371,  372.) 
Reactions  of  Tincture  of  Guaiacum. — A  trace  of  chlorine  im- 
parts to  tincture  of  guaiacum  an  intensely  blue  color.  H. 
Schiff  has  observed  the  following  reactions  :  with  iodine  a  dirty 
green,  or  no  coloration,  on  the  addition  of  water  blue ;  acids 
prevent  this  reaction,  not  the  neutral  salts.  The  tincture  when 
colored  blue  by  Fe2Cl3,  is  rendered  bright  violet  by  NaO,S202; 
the  liquid  is  rapidly  decolorized  ;  the  same  blue  tincture 
is  slowly  decolorized  by  S02,  but  immediately,  without  impart- 
ing any  purplish  color,  if  the  S02  has  been  previously  di- 
gested with  zinc.    Resin  of  guaiacum  dissolves  in  concentrated 
