298 
GLEANINGS  FROM  GERMAN  JOURNALS. 
of  iron  is  first  placed  upon  the  caoutchouc  stopper,  and  after  re- 
placing it  and  the  tube,  dilute  sulphuric  acid  is  poured  into  the 
upper  portion  of  the  vial.  When  gas  is  to  be  generated,  the 
tube  is  withdrawn  from  the  plug  so  as  to  let  the  acid  pass  into 
the  lower  portion  of  the  vial,  when  the  tube  is  again  inserted 
into  the  plug,  the  lower  portion  communicating  through  the 
aperture  with  the  open  end  of  the  tube  through  which  the  gas 
escapes  after  having  been  filtered  through  the  cotton. 
When  the  tube  is  pushed  through  the  plug  to  near  the  glass 
stopper,  the  apparatus  can  be  conveniently  carried  in  the  vest 
pocket. — Ihid.,  56-58. 
Water-hath. — C.  Ullgren  has  constructed  a  water-bath,  which 
is  almost  identical  with  the  water-baths  in  use  in  the  restaurants 
and  oyster  saloons  in  the  United  States  ;  the  water  is  heated  by 
a  Bunsen's  gas-lamp,  and  not  only  the  direct  heat,  but  also  the 
heat  of  the  hot  gases  of  combustion  is  utilized. — Ibid.  47. 
Test  f 07'  Sulphur. — Dr.  Schonn,  of  Stettin,  detects  sulphur  in 
organic  compounds  and  in  all  inorganic  sulphosalts,  sulphides, 
sulphocyanides,  sulphates,  &c.,  by  placing  a  little  of  the  dry 
substance  in  a  test  tube,  adding  a  small  piece  of  potassium  or 
sodium,  annd  covering  it  v/ith  more  of  the  dry  substance.  The 
tube  is  heated  until  the  reduction  is  completed  in  a  few  seconds, 
when  the  tube  is  broken  and  its  contents  thrown  into  a  dilute 
acid  or  a  solution  of  nitroprusside  of  sodium  ;  the  former  evolves 
sulphuretted  hydrogen,  the  latter  produces  the  well  known  violet 
color. — Ihid.  51-53. 
Test  for  Phosphorus. — Dr.  Schonn  detects  phosphorus  in  or- 
ganic and  inorganic  substances  by  mixing  the  anhydrous  powder 
with  magnesium  filings  and  heating  the  mixture  for  some  time 
in  a  test  tube.  If  now  a  few  drops  of  water  are  added,  phos- 
phoretted  hydrogen  is  given  oif  and  recognized  by  its  onion-like 
odor  ;  a  sublimation  of  red  phosphorus  and  phosphorescence  is 
often  observed,  if  magnesium  is  used  in  somewhat  larger  pro- 
portion ;  ammonio-phosphate  of  soda,  phosphate  of  soda,  burned 
bones,  &c.,  show  this  reaction  well. — Ibid.  53-56. 
Reduction  of  Silver. — Grager  (N.  Jahrb.  f.  Ph.  xxix,  9,)  ob- 
tains chemically  pure  silver  from  an  ammoniacal  solution  of 
