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On  the  Power  of  Soils  to  absorb  Manure. 
absorption  of  the  products  of  decay,  betrays  to  the  senses  no  indi- 
cation of  the  changes  going  on  beneath  the  surface.* 
But,  it  may  be  asked,  why  in  such  case  does  decay  proceed  at 
all  if  the  soil  has  a tendency  to  arrest  it  ? The  answer  is  simply 
this — a large  mass  of  animal  matter,  such  as  the  body  of  a dog, 
buried  in  the  earth  is  only  very  imperfectly  brought  into  contact 
with  the  soil,  and,  consequently,  decomposition  takes  place  with 
an  absorption  of  the  products  by  the  surrounding  earth.  The 
true  influence  of  the  soil  in  arresting  putrefaction  must  be  looked 
for  in  the  case  of  liquid  animal  products,  where  perfect  contact  of 
the  two  is  attained,  and  I have  shown  reason  for  the  belief  that  in 
such  cases  this  effect  does  really  occur. 
The  advantage  of  efficient  drainage  of  land  receives  an  inte- 
resting confirmation  from  the  facts  now  brought  forward.  To 
the  soil  is  intrusted  the  preservation  of  manure,  but  in  order 
that  this  preservative  power  may  be  exercised,  the  manure  which 
is  dissolved  by  rain  in  the  superficial  strata,  where  it  is  in  excess 
or  imperfectly  distributed,  must  be  brought  by  drainage  into 
contact  with  active  soil  below  by  which  it  will  be  taken  up.  If, 
on  the  other  hand,  the  land  be  undrained,  this  manure  is  carried 
off  the  surface  into  the  watercourses. 
Without  venturing  an  opinion  as  to  the  depth  of  drainage, 
which  must  depend  upon  many  circumstances,  it  may  be  fair  to  say 
that  it  should  be  such  as  to  ensure  the  absorption  of  the  manures 
by  the  soil  ; and  in  poor  soils  containing  little  clay,  and,  therefore, 
deficient  in  the  power  of  arresting  manure,  it  would  seem  that  the 
draining  off  of  water  should  not  be  the  only  object,  but  that  we 
should  seek  to  make  up  in  depth  of  soil  what  is  wanting  in 
activity. 
The  fertilizing  effect  of  burnt  clay  may  seem  to  be  at  variance 
with  the  experiments  which  have  been  brought  forward,  showing 
that  the  more  perfectly  we  burn  clay  the  more  certainly  and 
effectually  do  we  destroy  its  power  of  arresting  manure.  Let  it 
be  remembered,  however,  that  the  practice  of  burning  soils  is 
confined  principally  to  heavy  land  which  requires  opening,  that 
only  a part,  and  a small  part,  of  the  whole  is  burned,  and  that, 
although  the  absorbent  power — say,  for  example,  of  one-sixth  of 
the  soil — is  destroyed,  that  of  the  other  five-sixths  is  brought  into 
more  vigorous  action,  and  the  result  is  a positive  good.  It  must 
not  then  be  supposed  that  these  experiments  are  against  the 
* I am  informed  by  Mr.  Cunnington,  of  Devizes,  who  is  known  for  his  love  of 
natural  history,  that  the  North  American  Indians,  having  taken  a “skunk,”  or  species 
of  polecat,  which  stinks  intolerably,  in  order  to  sweeten  and  render  it  fit  for  food  bury 
the  carcase,  previously  skinned,  in  the  soil,  where  it.  speedily  loses  its  offensiveness. 
