388         APPARATUS  FOR  PREPARING  ETHER  BY  STEAM. 
just  fairly  in  sight  only;  for  if  it  rises  to  the  window  no  ordinary 
means  will  prevent  leaking  after  a  short  time. 
i.  An  ordinary  Liebig's  condenser  is  adapted  to  the  still,  and 
kept  cool  during  the  process,  by  a  current  of  water  entering 
through  india  rubber  tubing  at  j.  The  water  from  the  exit  pipe 
Jc.  is  conducted  by  india  rubber  tubing  into  the  first,  or  alcohol 
condenser  tub  as  required,  to  regulate  the  temperature  of  the 
water  there  to  about  105°. 
I.  A  curved  piece  of  thin  U  inch  lead  pipe  is  fitted  to  the  end 
of  the  Liebig,  having  a  small  lead  pipe  n  soldered  into  it  at  m, 
to  give  exit  to  the  watery  acid  liquid  condensed  in  the  Liebig. 
This  small  lead  pipe  is  «  trapped,"  or  bent  so  that  a  portion  of 
it  may  be  always  filled  with  liquid,  and  vapors  thus  prevented 
from  escaping.  The  farther  extremity  of  I  fits  into  pipe  r 
of  the  first,  or  alcohol  condenser  at  o,  and  is  regulated  in  its 
length  and  inclination  by  the  highth  at  which  the  condensers 
stand.  It  should  be  quite  as  long  as  represented,  and  with  quite 
as  much  rise. 
a'.  Two  tubs  for 
the  first  and  sec- 
ond, or  warm  and 
cold  condensers. 
The  first  for  sepa- 
rating the  alcohol 
from  the  ether  va- 
por, is  largest,  in 
order  to  accommo- 
date the  larger 
quantity  of  more 
expanded  vapors.     The  first  tub  is  kept  filled  with  water  at 
105°  to  110°,  and  the  second  with  ice,  or  cold  water. 
b'.  A  common  stand  for  the  two  tubs. 
These  condensers  and  tubes,  made  from  3  or  4  lbs.  lead,  or  from 
well  tinned  iron,  are  essentially  hollow  cylinders,  with  an  inside 
vertical  partition  to  prevent  the  vapors  from  passing  through 
them  without  circulation.  The  vapors  are  conducted  by  tubes 
r  and  v  into  these  hollow  cylinders  at  s  and  x  in  front  of  the 
vertical  partition  u\  fig.  2.    The  vapors  must  then  pass  entirely 
