Management  of  Manure. 
415 
“ The  addition  of  water,”  Sprengel  remarks,  “ has  this  advan- 
tage, that  the  diluted  liquid  contains  nearly  four  times  ” (more 
than  three  times)  “ as  much  ammonia  as  urine  left  to  putrefy  in  its 
natural  state,  though  it  retained  only  0 4 less  of  urea.”*  He 
supposes  that  a cow  produces  15,000  lbs.  of  urine  yearly,  and  that 
by  leaving  pure  urine  in  a tank  we  should  thus  lose  162  lbs.  of 
ammonia,  which,  at  Mr.  Way’s  estimate  of  6 cl.  per  lb.,  would 
be  a yearly  loss  of  four  pounds  sterling  per  cow  ; and  this,  too,  as 
compared  with  the  mixed  urine. 
Thclossof  ammonia  on  the  mixed  urine  is  severe,  amounting  in 
fact  to  one-fifth.  Well  may  Sprengel  say,  “ Whoever  is  obliged 
for  want  of  straw  to  collect  the  urine  separately,  whoever,  if 
compelled  to  do  this,  mixes  no  water  with  it,  or  fails  also  to 
employ  some  neutralizing  substance  to  combine  with  the  am- 
monia, suffers  a loss  of  manure  which  exceeds  all  belief.”  I can 
nowhere  find  how  much  water  is  necessary  to  save  all  the  ammonia. 
If  much,  the  labour  of  application  is  greatly  increased ; but 
however  much  water  be  used,  when  we  consider  how  slightly  even 
a heavy  shower  of  rain  penetrates  dry  ground,  I cannot  but  think 
that  much  of  the  ammonia  after  it  has  been  delivered  from  the 
cart  must  be  liable  to  escape.  Besides,  if  the  urine  be  collected 
separately  upon  system,  what  is  to  be  done  with  the  straw  ? It 
cannot  be  used  separately  as  dry  manure.  Are  we  to  cut  it  all 
up  into  chaff  as  food  for  stock  ? I do  this  largely  myself,  but  it 
may  be  done,  I think,  too  largely.  There  is  reason  to  think,  as 
we  have  seen,  that  the  good  effect  of  straw  in  supplying  carbon  as 
the  substance  of  crops  has  been  too  much  overlooked  lately.  Now 
it  is  clear  that  a large  part  of  the  straw  eaten  by  stock  is  literally 
consumed  by  them,  and  is  dissipated  like  smoke  through  their 
nostrils  in  their  breath.  According  to  Block,  a sheep  fed  on 
100  lbs.  of  rye-straw  with  water  voids  only  40  lbs.  of  excrements 
solid  and  fluid,  so  that  more  than  half  the  carbon  is  wasted. 
The  same  thing,  in  fact,  happens  as  in  the  obsolete  Lincolnshire 
practice  of  threshing  the  wheat  and  burning  the  straw  afterwards 
in  the  fields.  If  our  stock  eat  the  straw  from  100  acres,  we  have 
in  fact  burnt  the  produce  of  60  acres.  It  is  an  excellent  practice 
to  give  chaff  as  food ; yet  if  all  the  manure  be  applied  as  pro- 
posed in  a liquid  form,  we  might  burn  too  much  straw.  But 
there  is  another  of  the  three  great  manuring  substances, 
namely,  phosphorus,  about  which  we  have  to  inquire  in  judg- 
ing the  propriety  of  employing  liquid  manure ; and  when 
one  sees  it  stated  broadly  that  modern  science  has  decided  in 
favour  of  liquid  manure — when  one  reads,  too,  that  in  a Scotch 
county  iron  pipes  are  laid  down  over  a farm  of  nearly  400  acres, 
* Sprengel  on  Animal  Manures.  See  translation,  Journal,  i.  455. 
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