The  Woburn  Pot-Culture  Experiments , 1909.  347 
much  the  same.  The  crops  were  duly  cut  and  weighed  * and 
the  results  are  given  in  the  following  table,  in  which  are 
included  the  results  of  the  next  section  of  the  experiments 
also  : — 
Corn 
Straw 
Weight 
Percentage 
of 
untreated 
Weight 
Percentage 
of 
untreated 
Woburn  Soil. 
Grammes 
Per  cent. 
Grammes 
Per  cent. 
No  treatment  .... 
16-82 
100 
3104 
100 
Buxton  lime  ..... 
1618 
90 
26-58 
85 
„ limestone,  coarsely  ground 
17-74 
106 
31-48 
101 
„ „ finely  „ . 
18-18 
108 
31-26 
101 
Magnesian  lime  .... 
16-63 
98 
30-62 
98 
„ limestone,  coarsely  ground 
14-90 
89 
27-04 
87 
» »,  finely 
15-97 
95 
26  87 
86 
Herefordshire  Soil. 
No  treatment  . . • . 
32-63 
100 
40-78 
100 
With  lime  added,  to  1-25  per  cent. 
34-20 
105 
42-60 
104 
1*50 
32-77 
100 
45-67 
111 
,,  „ 1-75  „ 
29-03 
89 
4662 
114 
„ 2-00 
26-20 
77 
48-40 
119 
i)  ii  ii  2-25  ,, 
23  24 
71 
47  00 
116 
From  these  figures  it  would  appear,  in  the  first  place,  that 
the  influence  of  burnt  lime  had  been  inferior  to  that  of  ground 
limestone,  whether  coarse  or  fine  ; also  that  magnesia,  whether 
as  limestone  or  burnt  into  lime,  had  not  done  as  well  as  the 
pure  carbonate  of  lime.  The  former  result  is  quite  borne  out 
by  experience,  on  the  field  scale,  in  Stackyard  Field  (plot  2bb), 
where  applications  of  burnt  lime  have  not  shown  good  results 
at  the  outset  in  the  case  of  wheat,  but  have  required  time  to 
“ work.”  This  opens  up  the  question  as  to  whether  the 
“ alkalinity  ” of  the  burnt  lime  applied  has  had  an  influence 
in  lowering  the  crop  yield  ; also  a further  question  as  to 
whether  the  changes  due  to  the  use  of  lime  may  not  be  of 
a biological,  rather  than  of  a chemical,  nature.  And,  though 
the  results  from  the  use  of  magnesian  limestone  are  somewhat 
lower  than  in  the  case  of  the  untreated  plots,  the  difference  is 
not  sufficient  to  justify  the  drawing  of  definite  conclusions. 
Against  the  idea  of  “ alkalinity  ” being  harmful  is  the  fact  that 
there  is  no  evidence  of  this  where  burnt  magnesian  limestone 
had  been  used. 
The  results,  in  general,  point  to  the  desirability  of  continuing 
the  work  for  a second  year  or  longer,  and  this  will  be  done. 
. f 1 3.  The  influence  of  Lime  on  a soil  rich  in  Magnesia. 
< ■ An  extension  of  previous  work  on  the  use  of  lime  was 
carried  out  by  taking  a soil  naturally  richer  in  magnesia  than 
