390 
APPARATUS  FOR  PREPARING  ETHER  BY  STEAM. 
In  working  the  apparatus  for  three  consecutive  days,  however? 
55  gallons  of  alcohol,  and  101  lbs.  of  sulphuric  acid  were  used. 
From  these  materials  26J  gallons  of  rectified  ether,  of  s.  g.  -728 
were  obtained.  Beside  this,  5  gallons  of  alcoholic  ether  s.  g. 
•795  (for  tannic  acid  process)  and  2£  gallons  of  alcohol  s.  g. 
•840,  were  obtained  as  collateral  products  from  the  same  ma- 
terials. 
This  is  what  the  apparatus  has  done,  but  with  more  experience 
and  better  management  it  is  doubtless  capable  of  doing  better, 
so  that  at  the  next  operation  there  is  reason  to  expect  a  yield  of 
28  gallons  of  ether  s.  g,  «728  from  51  gallons  alcohol  s.  g.  -820, 
and  a  value  in  collateral  products  equal  to  the  expenses  of  the 
process,  if  wear  and  tear  of  apparatus  be  excluded. 
An  improvement  that  suggested  itself  at  the  last  operation, 
but  which  as  yet  has  only  been  experimentally  tried,  appears 
likely  to  render  practicably  applicable  the  method  of  Soubeiran, 
by  which  he  proposed  to  obtain  pure  concentrated  ether  at  one 
operation.  This  consists  in  substituting  for  the  ordinary 
Liebig's  condenser,  a  special  one  of  the  construction  shown  in 
figure  3. 
A  layer  of  sponge  or  curled  hair  being  placed  at  a,  the  large 
tube  is  to  be  loosely  filled  with  lumps  of  the  dried  residue  of  the 
ammonia  process,  (chloride  of  calcium  and  hydrate  of  lime,)  or, 
more  loosely  still  with  lumps  of  quick  lime.  The  hot  vapors  are 
thus  deprived  of  acid  entirely,  and  of  water,  in  a  measure,  and 
both  the  alcohol  and  ether  are  obtained  in  good  condition.  But 
how  long  the  good  effect  would  continue  to  be  produced  without 
renewing  the  contents  of  the  cooler,  remains  yet  to  be  deter- 
mined, whilst  upon  this  point  the  practicability  of  the  plan  en- 
tirely depends. 
If  this  fails,  however,  there  is  no  good  reason  why  the  mixed 
vapors  from  such  a  still  might  not  be  made  to  bubble  through  a 
warm  solution  of  chloride  of  calcium  and  milk  of  lime  before 
reaching  the  condensers,  provided  the  feeding  vessel  be  suf- 
ficiently elevated  to  oppose  the  increased  vapor  tension  in  the 
still,  and  provided  the  proportion  of  alcohol  in  the  charge  be  so 
varied  as  to  maintain  the  same  boiling  point  under  the  increased 
pressure. 
