The  Wohurn  Pot-Culture  Experiments,  1908.  393 
More  striking,  however,  were  the  results  produced  on  the 
grain.  Whereas,  on  examination  of  this,  after  harvest,  the 
wheat  from  the  untreated  and  from  the  ground  dolomite  sets 
was  found  to  be  almost,  or  entirely,  “starchy”  in  character,  in 
every  other  case  where  there  had  been  a marked  increase  in 
the  crop  the  grain  was  decidedly  glutinous.  Analyses  of  the 
grain  were  made  and  gave  the  following  percentages  of 
nitrogen  : — 
Nitrogen  in  grain 
per  cent. 
No  treatment  ......  1‘19 
Lime  and  magnesia  .....  1'58 
Carbonate  of  magnesia  . . . . 1'33 
Sulphate  of  magnesia 1'33 
Dolomite  (ground)  . . . . . 1'22 
Lime  from  dolomite  . . . . . 1 36 
It  will  be  noticed  that  the  grain  from  the  sets  (untreated 
and  dolomite  added),  which  gave  the  least  increase  of  crop, 
showed  also  the  lowest  percentage  of  nitrogen  in  the  grain. 
4.  Experiments  with  Fertilisers  on  Fen  soil. 
The  black  fen  soil  of  the  Isle  of  Ely  is  very  rich  in 
nitrogenous  organic  matter,  and,  in  consequence,  it  is  unusual 
to  use  on  it  any  nitrogenous  artificial  manure,  lest  the  crop 
“ go  down.”  The  present  experiment  was  devised  with  a view 
of  seeing  whether  small  dressings  of  nitrogenous  manures  in 
conjunction  with  minerals  would  be  advantageous,  and  also  if 
they  would  bring  about  the'  better  consolidation  of  the  soil, 
this  often  being  rendered  too  loose  by  the  continued  use  of 
farmyard  manure.  It  was  also  believed  that  the  large  stores 
of  nitrogenous  organic  matter  in  the  soil  were  but  imperfectly 
utilised,  through  their  being  but  slowly  broken  down,  and  it 
was  thought  possible  that  artificial  manuring  might  hasten  this. 
The  following  were  the  different  treatments  tried  per  acre  : — 
(a)  No  treatment. 
(h)  4 cwt.  superphosphate,  1 cwt.  sulphate  of  potash. 
(c)  1 cwt.  sulphate  of  ammonia. 
{d)  Nitrate  of  soda  = 1 cwt.  sulphate  of  ammonia. 
(e)  4 cwt.  superphosphate,  1 cwt.  sulphate  of  potash,  1 cwt. 
sulphate  of  ammonia. 
(/)  4 cwt.  superphosphate,  1 cwt.  sulphate  of  pbtash,  1 cwt. 
nitrate  of  soda. 
{g)  4 cwt.  superphosphate,  4 cwt.  kainit,  1 cwt.  nitrate  of 
soda. 
(K)  Soil  mixed  with  -10  per  cent,  magnesia  (MgO). 
In  this  experiment  the  mineral  manures  were  mixed  with  the 
top  layer  of  soil  (as  would  be  the  case  in  practice),  and  the  nitro- 
genous manures  were  applied  as  top- dressings  in  May,  1908. 
