GLEANINGS  FROM  GERMAN  JOURNALS. 
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GLEANINGS  FROM  GERMAN  JOURNALS. 
By  John  M.  Maisch. 
G-as  G-enerators. — Clemens  Ullgren,  of  Stockholm,  has  con- 
structed a  convenient  apparatus  for  the  generation  of  carbonic 
acid,  hydrogen  and  sulph-hydric  acid  gas  in  laboratories.  The 
generator  consists  of  a  cylindrical  glass  vessel,  the  mouth  of 
which  is  closed  by  a  twice  perforated  cork,  and  which,  through  a 
narrow  opening  at  its  bottom,  is  permanently  fastened  to  a  larger 
flat  glass  vessel,  intended  to  receive  from  the  cylinder  the  saline 
solution,  which  can  be  drawn  off  as  well  through  a  stop-cock  or  a 
bent  glass  tube  inserted  near  the  bottom.  The  generator,  through 
the  perforated  cork,  connects  with  a  wash  bottle  by  means  of  a 
bent  glass  and  caoutchouc  tube,  and  with  the  acid  receiver  near 
its  bottom  by  means  of  a  glass  tube  supplied  with  a  stop-cock  and 
a  strong  rubber  tube.  The  acid  receiver — a  plain  bottle  perforated 
on  one  side  near  its  bottom — is  imperfectly  closed  by  a  cork, 
through  which  a  bent  glass  tube  is  inserted.  The  author  uses 
muriatic  acid  diluted  with  water  until  it  ceases  to  give  off  fumes ; 
the  generator  is  filled  with  pieces  of  marble,  zinc  or  sulphide  of 
iron,  which,  by  some  pieces  of  glass,  are  prevented  from  falling 
into  the  vessel  below ;  the  acid  is  admitted  by  opening  the  stop- 
cock above  the  generator,  and  passing  through  the  material  in 
the  latter  is  completely  saturated,  while  a  uniform  current  of 
gas  is  evolved.  The  advantages  of  this  apparatus  are  that  the 
current  of  gas  can  be  regulated  by  the  flow  of  the  acid  through 
the  stop-cock,  and  can  be  discontinued  at  will ;  that  the  saline 
solution  is  not  in  contact  with  the  generating  material  and  may 
be  drawn  off  even  during  the  generation  of  the  gas,  and  that  the 
apparatus  is  easily  handled  and  always  ready  for  use. — Zeitschr. 
\  Analyt.  Chem.,  1869,  43-45. 
A  portable  sulphuretted  hydrogen  apparatus  has  been  con- 
structed by  F.  Jicinsky.  It  consists  of  a  small  glass  stoppered 
vial,  with  a  plug  of  caoutchouc  firmly  inserted  in  the  upper  half 
and  with  a  caoutchouc  stopper  in  place  of  the  bottom ;  both  the 
rubber  stopper  and  plug  are  perforated  for  receiving  a  glass 
tube  filled  with  cotton  and  closed  at  the  upper  end,  but  with  a 
small  aperture  a  little  below  ;  the  lower  end  is  open.  Sulphide 
