12  Oxygen  and  its  Medicinal  Application .{Ami£i*'$Q*rm- 
now  on  the  market.  The  one  in  use  by  the  writer  consists  of  a 
wooden  box  having  five  parallel  compartments  in  the  back  for 
wash  bottles  of  a  pint  capacity,  each  bottle  having  a  rubber 
cork  with  two  tubes,  one  dipping  down  into  the  contained  liquid, 
the  other  for  the  escape  of  the  washed  gas.  Each  of  the  bottles  is 
connected  with  the  other  by  means  of  rubber  tubing,  very  much 
in  the  same  way  as  in  the  Woulff  bottle.  The  first  bottle,  however, 
is  connected  with  the  generator,  and  this  needs  to  be  described. 
The  generator  is  placed  in  front  of  the  wash  bottles  and  consists 
of  two  cylinders  joined  together  at  the  centre  in  an  |_-shaped  fashion 
by  means  of  a  conical  stand  or  support,  both  of  which  cylinders  or 
retorts  are  removable  from  the  stand,  which  latter  is  firmly  attached 
to  the  box.  In  the  horizontal  copper  cylinder  there  is  placed  the 
mixture  for  generating  the  oxygen  gas,  while  through  the  upright 
one  passes  the  gas  generated.  Attached  to  the  posterior  part  of  the 
upright  cylinder,  there  is  connected  a  somewhat  smaller  cylinder  by 
means  of  a  lateral  tube  at  the  top  for  the  purpose  of  condensing 
any  moisture  which  may  be  present  in  the  oxygen-producing  mix- 
ture (which  liquid  may  be  removed  at  a  bottom  orifice  on  removing 
a  rubber  cork),  and  also,  to  receive  the  powdered  mixture  in  case  it 
should  be  carried  over  mechanically  from  the  horizontal  tube  by 
excessive  heat.    Were  this  not  the  case  explosion  might  result. 
After  the  gas  is  generated  by  heating  the  horizontal  tube,  it 
passes  in  succession  through  the  lateral  upright  cylinder  and  then 
through  two  series  of  wash  bottles.  The  first  two  contain  a  solution 
of  sodium  hydrate,  90  grains  in  ten  fluidounces  of  distilled  water. 
The  third  and  fourth  contain  a  solution  of  silver  nitrate,  15  grains 
in  ten  fluidounces  of  distilled  water.  The  last  bottle  is  filled  with 
absorbent  cotton  to  dry  the  gas  as  it  passes  through  it.  After  this, 
by  means  of  rubber  tubing,  the  dried  gas  passes  into  rubber  bags  of 
ten  gallons  capacity,  closed  by  means  of  a  vulcanite  stopcock.  When 
full  the  bag  is  disconnected.  To  use  the  gas,  there  comes  a  pint 
inhaling  bottle,  which  is  to  be  half  filled  with  water  prior  to  use.  It  is 
simply  an  ordinary  wash  bottle  with  rubber  cork,  tubes  and  tubing 
for  connection  with  the  mouth  and  the  supply  in  bag. 
The  mixture  for  generating  the  gas  is  composed  of  powdered 
potassium  chlorate,  four  pounds;  manganese  dioxide,  one  pound; 
and  precipitated  ferrous  carbonate,  sixty  grains.  Mix  and  triturate 
well  in  a  wedgwood  or  porcelain  mortar,  avoiding  force  or  severe  con- 
