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On  Irrigation  in  Switzerland. 
in  the  autumn,  and  does  not  feed  them  when  in  the  stable  with 
grass  cut  from  the  water-meadows,  but  with  grass  cut  from  the 
fields  which  have  been  manured.  There  is  a spring  on  his  estate 
which  contains  a large  amount  of  carbonic  acid  gas";  indeed  the 
poor  often  drink  it  as  a mineral  water,  and  the  water  from  this 
spring  possesses  remarkably  fertilizing  qualities.  M.  d’ Erlach 
also  told  me  that  water  which  is  previously  useless  for  irrigation, 
after  passing  through  mills  or  villages,  generally  becomes  avail- 
able. 
I also  paid  a visit  to  M.  de  Fellenberg’ s farm  at  Hofwyl. 
This  is  sit  uated  on  a conical  hill,  the  sides  of  which  slope  gradually 
away.  When  the  late  M.  de  Fellenberg  first  came  there  this 
hill  was  little  better  than  a swamp,  while  the  low  ground  was 
frequently  under  water.  Forty  feet  from  the  top  of  the  hill  there 
exists  a stratum  of  gravel,  at  which  depth  springs  were  discovered. 
M.  de  Fellenberg  conceived  the  idea  of  draining  the  whole  farm, 
and  applying  the  water  which  existed  on  the  gravel  bed  to  the 
irrigation  of  the  sides  of  the  hill.  He  formed  drains  mostly  from 
10  to  12  feet  in  depth,  covering  them  above  with  flat  stones,  and 
filling  them  up  with  loose  stones  till  within  3 feet  of  the  surface, 
where  he  placed  a layer  of  moss  to  prevent  the  soil  from  being 
carried  away  by  the  drains.  A constant  supply  of  water  is 
derived  by  means  of  the  drains  constructed  on  the  hill,  and  this 
water  is  collected  in  horizontal  channels  as  it  issues  from  the  hill 
side,  and  is  carried  along  the  hill-side  to  the  different  parts  of  the 
farm.  The  water-course  that  conveys  the  water  to  the  more  distant 
localities  is  covered  over,  so  that  the  water  may  not  be  affected 
by  the  temperature  of  the  air;  thus  when  applied  to  the  land  it 
is  warm  in  winter  and  cool  in  summer.  It  is  the  intention  of  M. 
de  Fellenberg  to  convert  the  whole  hill-side  into  water-meadows  : 
(part  is  now  arable  land.)  To  effect  this,  he  removes  the  subsoil  so 
as  to  make  the  surface  even,  taking  care,  however,  to  replace  the 
surface  soil : the  subsoil  so  removed  is  exposed  to  the  action  of 
the  air,  and  is  then  mixed  with  solid  manure  and  applied  as 
dressing. 
M.  de  Fellenberg  thinks  that  he  cannot  irrigate  too  much.  I 
never  saw  fields  look  brighter  or  greener  than  the  water-meadows 
on  his  farm;  and  the  grass  was  thick,  as  M.  de  Fellenberg  ex- 
pressed himself,  “ like  a brush.”  The  greater  the  fall  the  quicker 
the  grass  grows  (though  I should  observe  that  the  fall  was  in  no 
part  very  excessive).  M.  de  Fellenberg  irrigates  as  late  as 
possible  in  the  year,  and  only  stops  when  there  is  danger  of  the 
water  freezing  in  a mass  on  the  land  : as  long  as  the  water  trickles 
underneath  a surface  of  ice  he  continues  watering,  and  considers 
that  this  surface  of  ice  protects  the  roots  of  the  grass.  The  water 
is  made  to  flow  over  a certain  portion  of  land  for  twenty-four 
