316  GLEANINGS  FROM  THE  GERMAN  JOURNALS. 
Detection  of  Phosphorus. — The  phosphorus  globules  obtained 
in  Mitscherlich's  apparatus,  contain,  according  to  W.  Dankworth, 
also  sulphide  of  phosphorus,  if  the  original  mass  was  contami- 
nated with  sulphur.— (Arch.  d.  Ph.  civ.  168,  169.) 
Gun  Cotton  for  Collodium. — The  Archiv  der  Pharmacie,  civ. 
270-275,  reports  on  the  results  of  experiments  with  saltpetre 
and  sulphuric  acid,  from  which  the  following  process  is  deduced: 
1  oz.  cotton — from  a  larger  quantity,  a  less  good  product  is  ob- 
tained— is  introduced  into  a  mixture  of  16  oz.  saltpetre,^  12  oz. 
English,  and  12  oz.  Nordhausen  oil  of  vitriol  of  55  to  56^  R. 
(156  to  158^F),  and  continually  stirred  for  5  minutes ;  the  whole 
is  then  thrown  in  much  warm  water,  and  finally  well  washed. 
The  yield  is  about  120  per  cent,  and  the  cotton  readily  soluble 
in  ether. 
Titration  of  Alumina  in  Alum.  — 1.717  grm.  alum  are  dis- 
solved in  water,  2  grm.  chloride  of  barium  are  added,  and  the 
titration  carried  out  with  potassa  in  the  presence  of  litmus;  each 
cubic  centimetre  corresponds  with  1  per  cent,  alumina.  Or 
7.927  grm.  alum  and  10  grm.  chloride  of  barium  are  employed 
when  each  c.  c.  m.  potassa  indicates  2  per  cent.  alum. — (Archiv 
d.  Ph.  civ.  275-278.) 
Tin  and  Terchloride  of  Gold. — Dr.  Witting,  sen.,  found  that 
terchloride  of  gold  in  11.520  parts  water  rapidly  assumes  a  pur- 
ple color  in  contact  with  pure  tin  filings.  With  f  lead,  the  tin  re- 
acted slower  in  6000  water  ;  tin  with  copper  similar  in  8000  water, 
but  instantly  in  the  presence  of  electricity,  if  the  filings  were 
contained  in  spirally  wound  copper  and  silver  wire  (Arch.  d. 
Ph.  civ.  279.)' 
Bitter  Yeast. — C.  L.  Ludersen  removes  the  bitter  taste  of  30 
parts  of  yeast,  by  macerating  it  with  a  solution  of  1  p.  carbonate 
of  soda  in  240  p.  water,  and  washing  with  water;  an  increase  of 
soda  is  apt  to  produce  in  the  bread  a  peculiar,  though  not  un- 
pleasant odor  (Arch.  d.  Ph.  civ.  280,  281.) 
Perchromic  Acid. — The  blue  compound  resulting  from  mixing 
very  dilute  solutions  of  bichromate  of  potassa  and  binoxide  of 
hydrogen  with  free  acid,  was  dissolved  by  H.  AschoiF  in  ether. 
